fix(profile): move the now-playing channel description with the bot (#159)

When the bot was moved to another channel, the channel it left kept the
now-playing description forever: updateChannelDescription always targeted
getChannelId(), which by then already reported the new channel.

Remember which channel we last wrote to. On a self clientMoved event,
clear that channel and, if a song is playing, write the description to
the new one. Stop now clears the channel we actually wrote to, so a
missed move event can't leave a stale description behind either.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

.claude/settings.json

@@ -1,24 +0,0 @@
-{
-  "permissions": {
-    "allow": [
-      "Read",
-      "Edit",
-      "Write",
-      "Glob",
-      "Grep",
-      "Bash(*)",
-      "WebFetch(*)",
-      "WebSearch(*)",
-      "Agent(*)",
-      "mcp__Claude_Preview__*",
-      "mcp__Claude_in_Chrome__*",
-      "mcp__scheduled-tasks__*"
-    ],
-    "deny": [
-      "Bash(git push * main)",
-      "Bash(git push * master)",
-      "Bash(git push --force *)",
-      "Bash(rm -rf /)"
-    ]
-  }
-}

.claude/settings.local.json

@@ -1,26 +0,0 @@
-{
-  "permissions": {
-    "allow": [
-      "Read",
-      "Edit",
-      "Write",
-      "Glob",
-      "Grep",
-      "Bash(*)",
-      "WebFetch(*)",
-      "WebSearch(*)",
-      "Agent(*)",
-      "mcp__Claude_Preview__*",
-      "mcp__Claude_in_Chrome__*",
-      "mcp__scheduled-tasks__*",
-      "Bash(npx vitest:*)",
-      "Bash(cp \"C:\\\\Users\\\\saopig1\\\\.claude\\\\projects\\\\C--Users-saopig1-Music-teamspeak-music-bot\\\\b5a64d6f-051e-4b87-966c-ece97d2b879b\\\\tool-results\\\\webfetch-1776569008470-exv7qe.bin\" /tmp/design.gz)",
-      "Bash(gunzip -f /tmp/design.gz)",
-      "Read(//tmp/**)"
-    ],
-    "deny": [
-      "Bash(git push --force *)",
-      "Bash(rm -rf /)"
-    ]
-  }
-}

.gitignore

@@ -7,5 +7,7 @@ config.json
 cookies/
 .superpowers/
 .worktrees/
+.claude/
+setup.log
 /bin/
 scripts/navbar_bigger.png

README.md

@@ -5,41 +5,48 @@
 <h1 align="center">TSMusicBot</h1>
 
 <p align="center">
-  <strong>TeamSpeak 音乐机器人</strong> — 网易云音乐 + QQ 音乐 + 哔哩哔哩 + YouTube（可选），YesPlayMusic 风格 WebUI 控制面板
+  <strong>TeamSpeak 音乐机器人</strong> — 网易云音乐 + QQ 音乐 + 酷狗音乐 + 哔哩哔哩 + YouTube（可选），Jellyfin / Spotify 可选启用，YesPlayMusic 风格 WebUI 控制面板
 </p>
 
 <p align="center">
-  <img src="https://img.shields.io/badge/Node.js-20+-339933?logo=nodedotjs&logoColor=white" />
+  <img src="https://img.shields.io/badge/Node.js-20%20%7C%2022%20LTS-339933?logo=nodedotjs&logoColor=white" />
   <img src="https://img.shields.io/badge/TypeScript-5-3178C6?logo=typescript&logoColor=white" />
   <img src="https://img.shields.io/badge/Vue-3-4FC08D?logo=vuedotjs&logoColor=white" />
   <img src="https://img.shields.io/badge/许可证-MIT-green" />
   <img src="https://img.shields.io/badge/FFmpeg-已内置-orange?logo=ffmpeg" />
   <img src="https://img.shields.io/badge/Docker-支持-2496ED?logo=docker&logoColor=white" />
+  <img src="https://img.shields.io/badge/酷狗音乐-支持-2ca2f9" />
   <img src="https://img.shields.io/badge/BiliBili-支持-00a1d6?logo=bilibili&logoColor=white" />
+  <img src="https://img.shields.io/badge/Jellyfin-可选-aa5cc3?logo=jellyfin&logoColor=white" />
   <img src="https://img.shields.io/badge/YouTube-可选-FF0000?logo=youtube&logoColor=white" />
+  <img src="https://img.shields.io/badge/Spotify-可选-1DB954?logo=spotify&logoColor=white" />
   <img src="https://img.shields.io/badge/TS3-支持-2580C3?logo=teamspeak&logoColor=white" />
   <img src="https://img.shields.io/badge/TS6-支持-2580C3?logo=teamspeak&logoColor=white" />
 </p>
 
+> v1.10.0 新增**可选**的 [Jellyfin](https://jellyfin.org/) 音源（由 [@ItsEricRao](https://github.com/ItsEricRao) 在 [PR #123](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/123) 中贡献）：连接自建 Jellyfin 服务器直接播放你自己的音乐库。默认关闭，在 **设置 → Jellyfin 音乐库** 一键开启；原有在线音源保持默认启用，行为不变。
+
 ## 功能特性
 
 - **WebUI 鉴权与细粒度权限（必选）** — 用户名 + 密码登录，多用户、两种角色（管理员 / 成员）；成员可进一步配置**细粒度能力**（播放控制 / 队列管理 / 机器人管理 / 平台登录 / 音质）和**按机器人授权白名单**，所有变更操作由后端逐请求强制校验。bcrypt 加密、HttpOnly 会话 Cookie，CSRF 防护，WebSocket 同样鉴权。首次访问引导创建管理员。从无鉴权旧版本升级时请参阅 [更新升级](#更新升级) 章节
 - **游客模式（免登录点歌，默认关闭）** — 管理员可选择允许访客**无需账号密码**进入 WebUI 点歌，并逐项配置游客权限（8 个开关，默认仅「添加到队列末尾」开启）与可控机器人白名单；游客无法查看 / 修改任何设置、管理机器人或访问用户管理。开启后登录页出现 **「以游客身份进入」**。详见下文 **「游客模式 / Guest mode」** 小节
 - **本地收藏歌单** — 在首页 / 搜索 / 歌单页一键收藏，收藏内容按用户存储，登录后跨设备同步
-- **本地音频上传播放** — 在搜索页拖拽或选择本地音频上传，上传后可直接播放 / 下一首播放 / 加入队列；管理员可在 设置 → 行为设置 开关此功能，播放结束或停止/清空/替换队列时会清理服务端接收的本地文件
+- **保存/加载播放清单 + 重启后自动恢复队列（可选，默认关闭）** — 管理员在 设置 → 行为设置 开启后，可在网页「已存队列」页或聊天命令（`!save` / `!load` / `!queues`）把当前队列保存为清单，随时**替换**加载或**追加**到队列末尾；同时机器人重启后会自动恢复并继续播放上次的队列。网页保存可选「共享」，聊天保存进入共享清单。**说明**：重启只能从当前曲目的开头恢复（不记忆播放进度）；Spotify 自动恢复为尽力而为（依赖 sidecar 可用）。详见 [使用说明](#使用说明)
+- **本地音视频上传播放** — 在搜索页拖拽或选择本地文件上传，音频（mp3 / flac / wav / m4a / ogg / opus 等）和视频（mp4 / mov / avi / mkv / flv / wmv 等）都支持，视频上传后只保留其中的音轨；上传后可直接播放 / 下一首播放 / 加入队列；管理员可在 设置 → 行为设置 开关此功能，播放结束或停止/清空/替换队列时会清理服务端接收的本地文件
 - **专属链接（单机器人锁定）** — 通过 `/bot/<id>` 专属链接打开 WebUI 时锁定到单个机器人，刷新后保持，适合把某台机器人的控制页分享给特定用户
 - **频道无人时自动暂停** — 机器人所在频道没有其他人时自动暂停播放，有人加入后自动恢复（**默认关闭**，可在设置中开启）
-- **多平台音源** — 网易云音乐 + QQ 音乐 + 哔哩哔哩（默认内置），YouTube 可选启用（通过 yt-dlp），统一搜索，结果标注来源
+- **Jellyfin 音源（可选）** — 连接自建 [Jellyfin](https://jellyfin.org/) 服务器作为额外音源：搜索（歌曲 / 专辑 / 歌单）、懒解析直传播放、同步歌词、收藏 Instant Mix 电台（`!fm -j`）、首页「最近添加 / 播放最多 / 收藏 / 流派」，并把播放进度回报给 Jellyfin（PlayCount / 播放状态）。**默认关闭**，在 设置 → Jellyfin 音乐库 一键开启。详见 [可选：Jellyfin 音源](#可选jellyfin-音源)
+- **多平台音源（enabledProviders 门控）** — 网易云音乐 / QQ 音乐 / 酷狗音乐 / 哔哩哔哩 / YouTube（yt-dlp，需安装）**默认启用**，可在 `config.json` 的 `enabledProviders` 中逐个停用；Jellyfin 为可选音源（见上），**Spotify（实验性）** 由独立开关控制（需 Premium + 自建开发者应用，默认关闭，详见 [Spotify 音源（实验性）](#spotify-音源实验性)）。统一搜索（歌曲 / 歌单 / 专辑均支持翻页「加载更多」），结果标注来源，禁用音源不出现在搜索栏
 - **真实客户端协议 (TS3/TS6 双协议)** — 机器人在 TeamSpeak 中可见（非 ServerQuery 隐身模式），自动检测并适配 TS3 和 TS6 服务器，支持 TS6 HTTP Query API
 - **YesPlayMusic 风格 WebUI** — 精美界面，支持深色/浅色主题切换
 - **完整播放控制** — 播放/暂停/上一首/下一首/进度跳转/音量调节
 - **四种播放模式** — 顺序播放/循环播放/随机播放/随机循环
 - **实时歌词同步** — 歌词滚动显示，支持翻译歌词，服务端帧计数精确同步
-- **歌单管理** — 推荐歌单/我的歌单/每日推荐/私人FM，点击播放全部；私人 FM 支持网易云与 **QQ 音乐雷达推荐**（`!fm -q`）
+- **歌单管理** — 推荐歌单/我的歌单/每日推荐/私人FM，点击播放全部；私人 FM 支持网易云、**QQ 音乐雷达推荐**（`!fm -q`）与**酷狗私人电台**（`!fm -k`）。网易云、QQ、酷狗均提供登录后的推荐歌单 / 每日推荐 / 我的歌单
 - **音质选择** — 标准(128k) / 较高(192k) / 极高(320k) / 无损(FLAC) / Hi-Res / 超清母带
 - **B站视频音频提取** — 搜索B站视频，自动提取DASH最高码率音频流播放
 - **B站热门推荐** — 首页展示B站热门视频和个性化推荐（登录后更准确）
-- **QR码登录** — 扫码登录网易云/QQ音乐/哔哩哔哩账号，Cookie 自动持久化
+- **QR码登录** — 扫码登录网易云/QQ音乐/酷狗音乐/哔哩哔哩账号，Cookie 自动持久化
 - **机器人形象自动更新** — 播放时自动更新头像（专辑封面）、昵称（当前歌曲）、描述、Away 状态、频道描述，停止时恢复默认值。每项功能独立可配置，权限不足时自动降级
 - **多机器人独立播放** — 多个机器人同时在不同服务器或频道播放不同音乐，每个机器人独立的播放队列、进度和音量，WebUI 一键切换控制
 - **播放历史** — 自动记录所有播放过的歌曲
@@ -55,20 +62,25 @@
 
 ### 方式一：Windows 一键部署（最简单）
 
-只需电脑有网络连接，其他一切自动安装。
+先装好 Node.js，其余依赖（含内置 FFmpeg）全部自动安装。
 
 ```
-1. 下载或 clone 本项目
-2. 双击 scripts\setup.bat      （首次安装，自动安装 Node.js 和所有依赖）
-3. 双击 scripts\start.bat      （启动机器人）
-4. 浏览器打开 http://localhost:3000
+1. 安装 Node.js 22 LTS（https://nodejs.org/ 或 https://nodejs.cn/）
+2. 下载或 clone 本项目
+3. 双击 scripts\setup.bat      （安装依赖并构建，不含 Node.js 本身）
+4. 双击 scripts\start.bat      （启动机器人）
+5. 浏览器打开 http://localhost:3000
 ```
 
-> `setup.bat` 会自动通过 winget 安装 Node.js（如果未安装），运行 `npm install` 安装所有依赖（包括内置 FFmpeg），最后构建项目。之后每次只需双击 `start.bat` 启动。
+> **先装 Node.js 22 LTS**（[nodejs.org](https://nodejs.org/) / 国内镜像 [nodejs.cn](https://nodejs.cn/)）。`setup.bat` 检测到没装 Node 时会给出下载地址并退出，不会替你安装。
+>
+> 之后 `setup.bat` 会运行 `npm install` 安装所有依赖（包括内置 FFmpeg），按当前 Node 版本准备好原生模块，最后构建项目。之后每次只需双击 `start.bat` 启动。
+>
+> **Node 20 已不再支持**：better-sqlite3 从 12.10.0 起不再发布它那个 ABI（115）的预编译包，装起来必须先备好 Python + C++ 构建工具（[#152](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/152)）。Node 24 及更新的大版本能用，但 @discordjs/opus 0.10.0 同样没有 Node 24（ABI 137）的预编译包，安装脚本会改用源码编译，需要构建工具且耗时更久——所以推荐 22 LTS。**装好之后不要再换 Node 大版本**：原生模块只能在编译它的那个版本上加载，换版本后必须重新运行 `setup.bat`（脚本会自动检测并重装，见下方常见问题）。
 
 ### 方式二：手动安装（所有系统）
 
-**前置条件：** [Node.js 20+](https://nodejs.org/) 和一个 TeamSpeak 服务器（TS3/TS5/TS6 均可）。
+**前置条件：** [Node.js 22 LTS](https://nodejs.org/)（Node 24 及更新版本也能用，但需要源码编译原生模块；Node 20 已不再支持）和一个 TeamSpeak 服务器（TS3/TS5/TS6 均可）。
 FFmpeg **已自动内置**，无需手动安装。
 
 ```bash
@@ -161,6 +173,16 @@ sudo ./scripts/install.sh
 >
 > **如何判断是否需要迁移**：如果你是全新安装，或者你的机器人数据库中 `identity` 字段已经是空的，则**无需任何操作**。完成上述步骤后，按下面对应的系统升级步骤执行即可。
 
+### 关于 enabledProviders 音源开关（v1.10.0 起）
+
+v1.10.0（[PR #123](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/123)）引入 `enabledProviders` 音源开关与可选的 Jellyfin 音源。当前默认值为 `["netease", "qq", "bilibili", "youtube", "kugou"]`——**与旧版行为一致**，从更早版本升级**无需任何操作**，在线音源照常可用；Jellyfin 需要手动开启（详见 [可选：Jellyfin 音源](#可选jellyfin-音源)）。
+
+> ⚠️ **仅影响短暂运行过 v1.10.0 初版的用户**：该版本曾把默认音源设为 Jellyfin-only。如果你在那段时间保存过设置，`data/config.json` 中可能被写入了 `"enabledProviders": ["jellyfin"]`，升级后在线音源会保持停用。修复方法：把在线音源加回列表（或直接删除该字段以使用默认值），重启机器人（网易云 / QQ 的内嵌 API 服务需要重启才会启动）：
+>
+> ```json
+> "enabledProviders": ["netease", "qq", "bilibili", "youtube", "kugou", "jellyfin"]
+> ```
+
 ### 从 WebUI 无鉴权版本升级（重要）
 
 本次更新引入了**强制 WebUI 鉴权**。从无鉴权旧版本升级后，**WebUI 必须先创建管理员账号才能使用**。所有 `/api/*` 端点（除少量公共白名单）和 `/ws` 现在都需要登录。
@@ -300,19 +322,21 @@ sudo systemctl start tsmusicbot
    - 端口（默认 9987，自托管或非标准端口请填写实际值）
    - 机器人昵称
    - 可选：服务器密码、默认频道
-3. 在 **设置 → 音乐账号** 扫码登录网易云 / QQ 音乐 / B 站账号（可选，登录后可播放 VIP 歌曲）
-4. 在 **设置 → 用户管理**（仅管理员可见）按需添加成员。成员默认可控制播放但无法管理其他用户；管理员还可为每个成员单独配置**能力**（播放控制 / 队列 / 机器人管理 / 平台登录 / 音质）和**可操作的机器人白名单**，未授权的机器人对该成员不可见、不可控
+3. 在 **设置 → 音乐账号** 扫码登录网易云 / QQ 音乐 / 酷狗音乐 / B 站账号（可选，登录后可播放 VIP 歌曲、获取每日推荐 / 我的歌单等）
+4. （可选）在 **设置 → Jellyfin 音乐库** 连接自建 Jellyfin 服务器并打开「启用 Jellyfin 音源」（安装向导第 3 步保存连接时会自动启用；详见 [可选：Jellyfin 音源](#可选jellyfin-音源)）
+5. 在 **设置 → 用户管理**（仅管理员可见）按需添加成员。成员默认可控制播放但无法管理其他用户；管理员还可为每个成员单独配置**能力**（播放控制 / 队列 / 机器人管理 / 平台登录 / 音质）和**可操作的机器人白名单**，未授权的机器人对该成员不可见、不可控
 
 ### WebUI 页面说明
 
 | 页面 | 功能 |
 |------|------|
-| **首页** | 推荐歌单、每日推荐、私人FM（网易云 / QQ 雷达）、我的歌单、收藏的歌单 |
-| **搜索** | 三平台统一搜索，结果标注网易云/QQ/B站来源，可一键收藏歌单 |
+| **首页** | 推荐歌单、每日推荐、私人FM（网易云 / QQ 雷达 / 酷狗电台）、我的歌单、收藏的歌单（各源带标签切换）；启用 Jellyfin 后另有「Jellyfin 电台 / 最近添加 / 播放最多 / 收藏 / 流派」区块 |
+| **搜索** | 跨音源统一搜索（仅显示已启用的音源；启用 Jellyfin 后其结果排最前），结果标注来源，可一键收藏歌单 |
 | **歌单** | 查看歌单详情，播放全部（根据当前播放模式选择首歌），一键收藏 |
 | **歌词** | 全屏歌词页，实时同步滚动，模糊专辑封面背景 |
 | **历史** | 播放历史记录 |
-| **设置** | 账户（修改自己密码） / 主题切换 / 机器人管理 / 行为设置（空闲超时、频道无人自动暂停） / 三平台账号登录 / 音质选择 / 命令前缀 / 用户管理（仅管理员，含成员能力与机器人白名单）/ 操作审计（仅管理员） |
+| **已存队列** | 保存当前队列为清单、加载（替换）/ 追加 / 删除已保存清单（仅在管理员开启「保存/加载播放清单」后出现） |
+| **设置** | 账户（修改自己密码） / 主题切换 / 机器人管理 / 行为设置（空闲超时、频道无人自动暂停、保存/加载播放清单、单曲直接播放不清空队列） / 多平台账号登录（网易云 / QQ / 酷狗 / B站） / 音质选择 / 命令前缀 / 用户管理（仅管理员，含成员能力与机器人白名单）/ 操作审计（仅管理员） |
 
 ### TeamSpeak 文字命令
 
@@ -320,14 +344,17 @@ sudo systemctl start tsmusicbot
 
 | 命令 | 说明 |
 |------|------|
-| `!play <歌名>` | 搜索并播放（取最热门的匹配项） |
+| `!play <歌名>` | 搜索并播放（取最热门的匹配项；默认音源为网易云） |
+| `!play -n <歌名>` | 显式从网易云音乐搜索（默认音源即网易云，通常可省略） |
+| `!play -j <歌名>` | 从 Jellyfin 搜索（需先启用 Jellyfin 音源） |
 | `!play -q <歌名>` | 从 QQ 音乐搜索 |
+| `!play -k <歌名>` | 从酷狗音乐搜索 |
 | `!play -b <关键词>` | 从哔哩哔哩搜索视频并播放音频 |
 | `!play -y <关键词>` | 从 YouTube 搜索并播放（需要安装 [yt-dlp](#可选youtube-音源)）|
-| `!search <歌名>` | 列出前若干个匹配结果（含序号与 id），用于挑选同名歌曲 |
+| `!search <歌名> [-j\|-n\|-q\|-k\|-b\|-y]` | 列出前若干个匹配结果（含序号与 id），用于挑选同名歌曲；可加平台标志切换音源 |
 | `!play #<序号>` | 播放上一次 `!search` 结果中的第 N 项（区分同名歌曲） |
-| `!play id:<id>` | 按歌曲 id 播放精确的某首歌（也支持直接粘贴网易云 / QQ / B站 歌曲链接） |
-| `!add <歌名>` | 添加到播放队列（同样支持 `#序号` / `id:<id>` / 链接） |
+| `!play id <id>` | 按歌曲 id 播放精确的某首歌（也支持直接粘贴网易云 / QQ / B站 歌曲链接；Jellyfin 曲目用 GUID ItemId）。旧写法 `!play id:<id>` 仍然可用 |
+| `!add <歌名>` | 添加到播放队列（同样支持 `#序号` / `id <id>` / 链接） |
 | `!pause` / `!resume` | 暂停 / 恢复播放 |
 | `!next` / `!prev` | 下一首 / 上一首 |
 | `!stop` | 停止播放并清空队列 |
@@ -335,19 +362,26 @@ sudo systemctl start tsmusicbot
 | `!queue` | 查看播放队列 |
 | `!remove <位置>` | 从队列中删除指定位置的歌曲（位置从 1 开始，见 `!queue`） |
 | `!mode <seq\|loop\|random\|rloop>` | 切换播放模式 |
-| `!playlist <歌单名或ID>` | 加载歌单（支持名称模糊搜索和 ID） |
+| `!playlist <歌单名或ID>` | 加载歌单（支持名称模糊搜索和 ID；Jellyfin 歌单 GUID 也可直接粘贴） |
 | `!playlist -q <歌单名>` | 从 QQ 音乐搜索并加载歌单 |
-| `!album <ID>` | 加载专辑 |
-| `!artist <歌手名>` | 按歌手循环播放（支持 `-q`/`-b`/`-y`） |
-| `!fm` | 私人 FM（网易云，自动续播） |
+| `!album <专辑名或ID>` | 加载专辑（支持名称搜索 / 数字 ID / Jellyfin GUID） |
+| `!artist <歌手名>` | 按歌手循环播放（支持 `-j`/`-n`/`-q`/`-k`/`-b`/`-y`） |
+| `!fm` | 私人 FM（默认网易云，自动续播） |
+| `!fm -j` | Jellyfin 电台：从收藏出发的 Instant Mix（需启用 Jellyfin，自动续播） |
 | `!fm -q` | QQ 音乐雷达 / 猜你喜欢 FM（自动续播） |
-| `!lyrics` | 显示当前歌词 |
+| `!fm -k` | 酷狗私人电台 / 个性化推荐 FM（自动续播） |
+| `!lyrics` | 显示当前完整歌词（自动分多条消息发送，不再只显示开头几行） |
 | `!now` | 当前播放信息 |
 | `!vote` | 投票跳过当前歌曲 |
 | `!move <频道名>` | 移动到指定频道 |
+| `!save <名称>` | 保存当前队列为一份已保存清单（需启用「保存/加载播放清单」，聊天保存进入共享清单） |
+| `!load [-a] <名称>` | 加载已保存清单（默认替换当前队列并播放；加 `-a` 追加到队列末尾） |
+| `!queues` | 列出已保存（共享）清单 |
 | `!help` | 显示帮助信息 |
 
 > 命令前缀默认为 `!`，可在设置页面修改。支持别名：`!p` = `!play`，`!s` = `!skip`，`!n` = `!next`
+>
+> `!save` / `!load` / `!queues` 仅在管理员开启「保存/加载播放清单」后可用（默认关闭），未启用时回复「此功能未启用」。
 
 ### TeamSpeak 命令权限（管理类命令限制）
 
@@ -372,6 +406,8 @@ sudo systemctl start tsmusicbot
 
 ### 音质等级
 
+**在线音源（网易云等）**
+
 | 等级 | 码率 | 格式 | 说明 |
 |------|------|------|------|
 | 标准 | 128kbps | MP3 | 免费可用 |
@@ -381,8 +417,29 @@ sudo systemctl start tsmusicbot
 | Hi-Res | ~1500kbps | FLAC | 需要 VIP |
 | 超清母带 | ~4000kbps | FLAC | 需要黑胶 VIP |
 
+**Jellyfin（启用后）**
+
+| 等级 | 说明 |
+|------|------|
+| **原始直传（direct）** | **默认**：原始文件不转码直传（机器人本地统一转 Opus，此档即最高音质） |
+| 320kbps / 192kbps / 128kbps | 由 Jellyfin 服务器转码后传输，适合公网带宽有限的自建服务器 |
+
 在设置页面选择音质，立即生效（影响后续播放的歌曲）。
 
+> **重启后保留（#125）**：音质选择会持久化到 `data/config.json`（每个平台各自记录），重启机器人后自动恢复，无需每次手动重设。
+
+### 重启后保留的播放设置
+
+以下运行时设置在改动时自动落盘，重启机器人后自动恢复，不再回到默认值：
+
+| 设置 | 作用范围 | 存储位置 |
+|------|----------|----------|
+| **播放音量**（`!vol` / WebUI 音量条 / REST `/volume`） | 每个机器人独立 | 数据库 `bot_instances.volume` |
+| **播放模式**（`!mode` / WebUI / REST `/mode`：顺序 / 列表循环 / 随机 / 随机循环） | 每个机器人独立 | 数据库 `bot_instances.play_mode` |
+| **音质**（各平台，WebUI 设置页 / REST `/quality`） | 全局（各平台各自记录） | `data/config.json` 的 `audioQuality` |
+
+聊天命令、WebUI、REST API 三种入口的改动都会被持久化。播放队列、当前歌曲、进度、`!fm` / `!artist` 等临时播放状态仍为一次性状态，重启后不保留（`!fm` / `!artist` 内部临时切换的随机 / 循环也**不会**覆盖你用 `!mode` 显式保存的偏好）。
+
 ## 项目架构
 
 ```
@@ -404,9 +461,11 @@ teamspeak-music-bot/
 │   │   └── database.ts         # SQLite 数据库（播放历史、实例、收藏、权限持久化）
 │   ├── music/                  # 音源服务
 │   │   ├── provider.ts         # 统一 MusicProvider 接口
+│   │   ├── jellyfin.ts         # Jellyfin 适配器（可选音源，直连 REST API）
 │   │   ├── netease.ts          # 网易云音乐适配器
 │   │   ├── qq.ts               # QQ 音乐适配器
 │   │   ├── bilibili.ts         # 哔哩哔哩适配器（视频音频提取）
+│   │   ├── kugou.ts            # 酷狗音乐适配器（直连 API，无 npm 依赖 / 无内嵌服务）
 │   │   ├── youtube.ts          # YouTube 适配器（可选，依赖 yt-dlp）
 │   │   ├── auth.ts             # Cookie 持久化存储
 │   │   └── api-server.ts       # 嵌入式 API 服务（自动启动）
@@ -451,19 +510,79 @@ teamspeak-music-bot/
 
 | 层级 | 技术 |
 |------|------|
-| **运行时** | Node.js 20+, TypeScript 5 |
+| **运行时** | Node.js 22 LTS（推荐）, TypeScript 5 |
 | **后端框架** | Express 4, WebSocket (ws) |
 | **数据库** | better-sqlite3 (SQLite) |
 | **音频处理** | FFmpeg (ffmpeg-static 内置), @discordjs/opus |
 | **TS 协议** | @honeybbq/teamspeak-client（完整客户端协议）+ 自研 TS6 协议适配层 |
+| **Jellyfin** | Jellyfin REST API（可选音源，直连，无额外 npm 依赖） |
 | **网易云 API** | NeteaseCloudMusicApi |
-| **QQ 音乐 API** | @sansenjian/qq-music-api |
+| **QQ 音乐 API** | @sansenjian/qq-music-api（锁定 `~2.4.0`，需 Node ≥ 20.17） |
 | **哔哩哔哩** | BiliBili Web API（搜索、DASH 音频流、QR 登录） |
+| **酷狗音乐** | 酷狗公开 API（直连，无 npm 依赖 / 无内嵌服务；请求签名 / KRC 歌词解码 / 设备注册移植自 MIT 的 MakcRe/KuGouMusicApi，改用 Node 内置 crypto + zlib） |
 | **前端框架** | Vue 3, Vite 5, Pinia, Vue Router 4 |
 | **界面样式** | SCSS（YesPlayMusic 设计风格） |
 | **图标** | @iconify/vue |
 | **日志** | pino |
 
+## 可选：Jellyfin 音源
+
+本项目可将自建 [Jellyfin](https://jellyfin.org/) 媒体服务器作为**额外音源**：机器人直接播放你自己音乐库里的文件，不依赖任何在线平台的可用性 / 版权 / 登录状态。该音源**默认关闭**，需要手动启用。
+
+### 启用与连接配置
+
+三种方式任选：
+
+1. **首次安装向导** — 第 3 步即 Jellyfin 连接卡（可跳过，稍后配置）；填写并「保存并继续」会**自动启用**该音源。
+2. **WebUI** — 设置 → Jellyfin 音乐库（可选）：打开「**启用 Jellyfin 音源**」开关，填写服务器地址、选择认证方式、「测试连接」验证后保存，**保存即时生效，无需重启**。
+3. **config.json** — 手动编辑 `jellyfin` 配置块，并把 `"jellyfin"` 加入 `enabledProviders`，然后重启。
+
+两种认证方式：
+
+| 模式 | 填写内容 | 说明 |
+|------|---------|------|
+| **账号密码**（默认） | `username` + `password` | 以该用户身份登录（`AuthenticateByName`），token 自动持久化、失效自动重登 |
+| **API Key** | `apiKey` + `userId` | 使用管理后台生成的 API Key；`userId` 决定使用谁的音乐库 / 收藏 / 歌单 |
+
+```jsonc
+// config.json 片段
+{
+  "jellyfin": {
+    "serverUrl": "https://jellyfin.example.com",
+    "authMode": "userpass",     // 或 "apikey"
+    "username": "music",
+    "password": "······",
+    "apiKey": "",               // apikey 模式填写
+    "userId": ""                // apikey 模式填写
+  },
+  "enabledProviders": ["netease", "qq", "bilibili", "youtube", "kugou", "jellyfin"]
+}
+```
+
+> 密码 / API Key 在 WebUI 中**只写不回显**；表单留空表示保持已保存的值不变。
+
+### 功能
+
+- **搜索** — 歌曲 / 专辑 / 歌单，支持翻页「加载更多」；WebUI 统一搜索中 Jellyfin 结果排最前
+- **播放** — 懒解析播放地址；默认**原始直传**（不经 Jellyfin 转码），也可选 320/192/128kbps 服务器转码档（设置 → 音质设置）
+- **歌词** — 读取 Jellyfin 的歌词接口（内嵌或 .lrc），时间轴同步滚动，`!lyrics` 可用
+- **电台 / FM**（`!fm -j` 或首页「Jellyfin 电台」卡片）— 随机取一首**收藏**做种子生成 Instant Mix 歌曲流；没有收藏则回退到最近播放、再回退随机曲目
+- **首页区块** — 最近添加（专辑）/ 播放最多 / Jellyfin 收藏 / 我的歌单 / 流派（点流派芯片即播放该流派）
+- **播放上报** — 播放开始 / 进度（约 10s 一次）/ 停止会回报给 Jellyfin（`Sessions/Playing` 系列接口），你的 Jellyfin 播放统计（PlayCount、最近播放）保持准确；上报失败不影响播放
+- **聊天命令** — 启用后用 `-j` 标志：`!play -j <歌名>`、`!fm -j`、`!artist -j <歌手>`；`!playlist` / `!album` / `!play id <id>` 可直接粘贴 Jellyfin GUID。若把在线音源全部停用、只保留 Jellyfin，不带标志的命令会自动以 Jellyfin 为默认音源
+
+### enabledProviders：音源开关
+
+`config.json` 的 `enabledProviders` 数组决定哪些音源可用（默认 `["netease", "qq", "bilibili", "youtube", "kugou"]`，即在线音源全开、Jellyfin 关闭）：
+
+- 可选值：`jellyfin`、`netease`、`qq`、`bilibili`、`youtube`、`kugou`（`local` 由 `localAudioEnabled` 控制，`spotify` 由 `spotify.enabled` 控制）
+- 未列出的音源：聊天命令返回「音源未启用」、REST 返回 400、WebUI 搜索栏 / 登录卡 / FM 卡片自动隐藏
+- 不带平台标志的命令默认走**固定优先级中第一个已启用的音源**：网易云 → QQ → 酷狗 → Jellyfin → B站 → YouTube（默认配置下即网易云）
+- **自定义默认音源（`defaultPlatform`）** — 想让不带标志的 `!play 歌名` 直接用某个音源（例如常听哔哩哔哩，免去每次加 `-b`），可在 设置 → 默认音源 里选择，或在 `config.json` 中设置 `"defaultPlatform": "bilibili"`。取值须是 `enabledProviders` 里已启用的音源，否则被忽略（回退到上面的固定优先级）；留空 / `null` / 删除该字段即恢复固定优先级。WebUI 保存后即时生效，无需重启
+- 网易云 / QQ 停用时，其内嵌 API 服务（端口 3001 / 3200）**不会启动**
+- 示例（Jellyfin 为主、只留网易云备用）：`"enabledProviders": ["jellyfin", "netease"]`（默认音源仍为网易云，点歌用 `-j`、停用网易云，或直接把 `defaultPlatform` 设为 `"jellyfin"`）；示例（纯 Jellyfin）：`"enabledProviders": ["jellyfin"]`
+- 注意：重新启用网易云 / QQ 的内嵌 API 服务需要重启机器人；其余音源改动即时生效（WebUI 的 Jellyfin 开关即改此列表）
+
 ## 可选：YouTube 音源
 
 YouTube 是**可选**的音源，默认**未启用**，需要安装 [yt-dlp](https://github.com/yt-dlp/yt-dlp) 才能使用。启用后可通过聊天命令 `!play -y <关键词>` 或 WebUI 的 YouTube 平台选项搜索/播放 YouTube 视频的音频流。
@@ -513,6 +632,131 @@ pip install -U yt-dlp
 - 受 YouTube 风控/地域限制，部分视频可能无法播放
 - `yt-dlp` 更新较频繁，如果播放失败，先尝试升级 `yt-dlp` 到最新版本
 
+## Spotify 音源（实验性）
+
+> **⚠️ 实验性功能，启用前请务必读完本节**
+>
+> - **需要 Spotify Premium 账号。** 免费账号无法通过 Spotify Connect 输出音频，无法使用本功能。
+> - **使用你自己在 Spotify Developer Dashboard 注册的应用（Client ID）。** 本项目**不内置任何共享凭据**，也不会替你代管账号。
+> - Spotify 官方并未开放第三方播放的公开授权，本功能处于 **Spotify 服务条款的灰色地带**，是否使用请自行评估，**风险自负**。
+> - 该音源**默认关闭**（`spotify.enabled = false`），需要手动开启并完成授权。
+> - 这**不是** YouTube 那样的「免登录回退音源」，而是**真正的 Spotify 音频**，必须有 Premium 才能出声；音频链路依赖第三方开源解码器（librespot / go-librespot），本项目仅在本地作为独立子进程调用，**播放效果不做保证**，也未在本仓库端到端测试。
+
+### 工作原理（简述）
+
+1. `librespot`（Rust）或 `go-librespot`（Linux）作为**独立子进程**登录 Spotify Connect 并解码音频，输出原始 **PCM**。
+2. 本项目用内置 **ffmpeg** 把 PCM 重采样到 **48kHz**。
+3. 重采样后的音频接入**现有的 Opus 编码 / 发送管线**（与其它音源共用），推送到 TeamSpeak。
+4. 歌名、歌手、封面等**元数据来自 Spotify Web API**。
+
+### 平台矩阵
+
+后端由配置项 `spotify.backend` 决定，可选 `auto`（默认）/ `go-librespot` / `librespot`：
+
+| 平台 | 默认后端（`auto`） | 说明 |
+|------|------|------|
+| Windows | `librespot`（Rust） | 不支持 go-librespot（FIFO 仅限 POSIX，且官方无 Windows 资产） |
+| Linux / Docker | `go-librespot`（可回退 `librespot`） | `auto` 优先 go-librespot，未检测到时自动改用 librespot |
+| macOS | `librespot`（Rust） | 与 Windows 同，仅支持 Rust 版 |
+
+> `auto` 会按平台与二进制可用性自动选择：优先 `go-librespot`（若可用），否则 `librespot`。若显式指定 `go-librespot` 或 `librespot` 但对应二进制不存在，则该音源保持不可用。
+
+### 获取二进制
+
+程序会先在项目根目录的 `bin/` 中查找，找不到再回退到系统 `PATH`。`bin/` 已被 `.gitignore` 忽略，不影响代码更新。
+
+**Rust librespot（librespot-org，全平台）** — 官方**没有预编译发布包**，需自行获取（任选其一）：
+
+```bash
+# 方式 1：用 Cargo 编译安装（需要 Rust 工具链）
+cargo install librespot
+
+# 方式 2（Windows）：scoop / choco
+scoop install librespot        # 或：choco install librespot
+
+# 方式 3：把可执行文件放到项目 bin/ 目录
+#   Windows:      bin/librespot.exe
+#   Linux/macOS:  bin/librespot
+```
+
+或直接把 `librespot` 加入系统 `PATH`。
+
+**go-librespot（仅 Linux）** — 官方仅提供 **Linux** 预编译资产：
+
+```bash
+# 从 Release 页下载对应架构的二进制：
+#   https://github.com/devgianlu/go-librespot/releases
+# 放到项目 bin/ 目录（或加入系统 PATH）：
+#   bin/go-librespot
+```
+
+> **Windows 不支持 go-librespot**：它依赖 POSIX FIFO（`mkfifo`），官方也只发布 Linux 资产。Windows / macOS 请使用 Rust `librespot`。
+
+### 注册 Spotify 开发者应用 + 回调地址
+
+1. 打开 [Spotify Developer Dashboard](https://developer.spotify.com/dashboard)，新建一个应用，记下 **Client ID**。
+2. 在应用设置里添加 **Redirect URI（回调地址）**，精确填写：
+
+   ```
+   http://127.0.0.1:<webPort>/api/spotify/callback
+   ```
+
+   其中 `<webPort>` 与本项目设置里的 Web 端口一致（默认 `3000`，即 `http://127.0.0.1:3000/api/spotify/callback`）。回调路径必须精确为 `/api/spotify/callback`。
+3. 本项目使用 **Authorization Code + PKCE** 流程，**不需要 Client Secret**（配置里的 `clientSecret` 可留空）。
+4. 授权时请求的权限范围（scope）：
+
+   ```
+   streaming user-read-playback-state user-modify-playback-state user-read-currently-playing playlist-read-private
+   ```
+
+### 启用步骤
+
+1. 进入**设置页**的「连接 Spotify」卡片。
+2. 填入 **Client ID**、选择**后端**（`auto` / `go-librespot` / `librespot`）、打开**开关**。
+3. 点击**保存**。
+4. 点击「**连接 Spotify**」，在弹出的 Spotify 页面完成 **OAuth 授权**。
+
+> 仅当 **`enabled = true`** + **已完成 OAuth 授权** + **检测到可用的后端二进制** 三者同时满足时，Spotify 音源才可播放。任一条件不满足，该音源保持**不可用**（点播会被跳过，播放队列照常前进，不影响其它音源）。
+
+对应的配置块（`data/config.json`）：
+
+```json
+{
+  "spotify": {
+    "enabled": false,
+    "backend": "auto",
+    "clientId": "",
+    "clientSecret": "",
+    "deviceName": "TSMusicBot",
+    "bitrate": 320
+  }
+}
+```
+
+OAuth 相关端点：`/api/spotify/login`、`/api/spotify/callback`、`/api/spotify/status`。
+
+### 许可与来源
+
+- **go-librespot** 采用 **GPL-3.0** 许可。本项目**仅将其作为独立子进程调用**（mere aggregation / 独立聚合），**不链接、不打包**其代码，因此**不影响本项目自身的 MIT 许可**。
+  - 源码与许可：<https://github.com/devgianlu/go-librespot>（GPL-3.0；如需其对应源码请前往该仓库获取 —— source offer）。
+- **Rust librespot** 采用 **MIT** 许可：<https://github.com/librespot-org/librespot>。
+
+### 故障排查
+
+| 现象 | 处理 |
+|------|------|
+| 提示「未检测到 librespot / go-librespot」 | 检查项目 `bin/` 目录里是否放了可执行文件，或该命令是否在系统 `PATH` 中；Rust 版可用 `cargo install librespot` 安装 |
+| 提示「未授权 / 需要连接 Spotify」 | 在设置页「连接 Spotify」卡片点击「连接 Spotify」完成 OAuth 授权 |
+| Windows 上无法使用 go-librespot | 属预期行为（FIFO 仅限 POSIX，官方无 Windows 资产）；请把 `backend` 设为 `librespot` 或 `auto` |
+| 完全没有声音 | 确认账号为 **Spotify Premium**；免费账号无法通过 Spotify Connect 输出音频 |
+
+### 已知限制
+
+- 在多租户/共享主机上，librespot 通过命令行参数接收访问令牌，同机其他本地进程理论上可读取（令牌约 1 小时有效，需本地访问权限）。
+- Spotify 连续播放（gapless spotify→spotify）时，网页进度条的"已播放时间"可能不准确（以后端上报的播放进度为准）。
+- 运行多个启用 Spotify 的 bot 时，若两个 bot 的 id 端口哈希发生冲突（同一 % 1000 桶），第二个 go-librespot 边车会因端口占用而启动失败、该 bot 的 Spotify 不可用（后续将改为按需分配空闲端口）。
+- **一个 Spotify Premium 账号只支持「一路」正在播放的音频流**。因此若要同时运行**多个**启用 Spotify 的 bot 并让它们各自独立播放，必须为**每个 bot 配置独立的 Spotify 账号**。在 Rust（librespot）后端上，本机制已把播放控制（暂停/继续/跳转）限定到 bot 自己的设备，并在读取播放状态时忽略其它设备的状态，以避免多 bot 之间互相抢占、来回抖动（cross-control/thrash）；但受 Spotify 平台限制，**共用同一账号无法实现多路同时播放**（第二个 bot 开始播放会夺走该账号唯一的活跃会话）。go-librespot 后端为每个边车独立的本地 REST API，不受此账号级抢占影响。
+
 ## 配置文件
 
 配置文件位于 **`data/config.json`**（与数据库、Cookie、日志同在持久化的 `data/` 目录，Docker 部署对应挂载卷），首次运行时自动生成，可手动编辑：
@@ -558,11 +802,14 @@ A：支持。本项目内置 TS3/TS6 双协议支持，连接时会自动检测
 **Q：机器人连接了但 TeamSpeak 中听不到音乐？**
 A：确保机器人和你在同一个频道。检查音量（`!vol 75`）。部分 VIP 歌曲需要先登录账号。
 
+**Q：启动报 `NODE_MODULE_VERSION 137 ... requires 127`，或提示找不到 `opus.node`？**
+A：换过 Node 大版本了。原生模块（`@discordjs/opus`、`better-sqlite3`）编译时绑定了一个 Node ABI（Node 20 = 115、22 = 127、24 = 137），换版本后旧的 `.node` 就再也加载不了。**重新运行一次 `scripts\setup.bat`（Linux/macOS 是 `bash scripts/setup.sh`）即可**——安装脚本会实际加载一遍每个原生模块，发现和当前 Node 不匹配就自动重新下载/编译，替换过程中失败也会把原来的文件还原回去。`start.bat` 和 `npm start` 在启动前也会先做这个检查，直接告诉你哪个模块对不上、分别是哪个 ABI，而不是抛一串看不懂的堆栈。想彻底重来就删掉 `node_modules` 和 `web\node_modules` 再跑一次 `setup.bat`。
+
 **Q：提示"无法获取播放链接"？**
 A：在设置页面扫码登录音乐账号。许多歌曲需要登录后才能播放。
 
 **Q：同名歌曲 `!play` 只能播到最热门的那首，怎么播放指定的版本？**
-A：`!play <歌名>` 默认取最热门的匹配项。要播放同名的另一首，有三种方式：(1) 先 `!search <歌名>` 列出带序号的结果，再 `!play #序号` 选择；(2) `!play id:<歌曲id>` 按 id 精确播放；(3) 直接粘贴歌曲链接，如 `!play https://music.163.com/song?id=442867526`（也支持 QQ / B站 链接）。在 WebUI 中则可直接在搜索结果列表里点选任意同名歌曲。
+A：`!play <歌名>` 默认取最热门的匹配项。要播放同名的另一首，有三种方式：(1) 先 `!search <歌名>` 列出带序号的结果，再 `!play #序号` 选择；(2) `!play id <歌曲id>` 按 id 精确播放（`!search` 结果里每行末尾的 `[id:...]` 就是它）；(3) 直接粘贴歌曲链接，如 `!play https://music.163.com/song?id=442867526`（也支持 QQ / B站 链接）。在 WebUI 中则可直接在搜索结果列表里点选任意同名歌曲。
 
 **Q：如何更换机器人所在频道？**
 A：使用 `!move <频道名>` 命令，或在设置页面创建机器人时指定默认频道。
@@ -571,7 +818,16 @@ A：使用 `!move <频道名>` 命令，或在设置页面创建机器人时指
 A：可以。在设置页面创建多个实例，分别连接不同的 TS 服务器或频道。
 
 **Q：端口 3200 被占用？**
-A：QQ 音乐 API 启动时自动监听 3200 端口。如果之前的进程还在运行，程序会自动复用。如需重启可手动结束 `node` 进程。
+A：QQ 音乐 API 启动时会监听 `config.json` 里的 `qqMusicApiPort`（默认 **3200**），客户端也用同一个端口发请求，二者始终一致。如果之前的进程还在运行，程序会自动复用。如需改端口，改 `qqMusicApiPort` 后重启即可；如需重启可手动结束 `node` 进程。
+
+**Q：日志里 `baseURL` 是 3200，但 QQ API 实际监听在 3300？（二维码不弹）**
+A：这是**旧版本**（或过期的 `latest` Docker 镜像）才有的问题：早期实现用的上游包默认端口是 3300，而客户端 `baseURL` 已经是 3200，两边对不上，取二维码时就 `ECONNREFUSED 127.0.0.1:3200`。当前版本已把内嵌 QQ 音乐 API **强制绑定到 `qqMusicApiPort`（默认 3200）**，并在启动前把上游包读取的 `PORT` 环境变量对齐到该端口，二者不可能再错位。修复方法：**拉取最新镜像并重启**（`docker compose pull && docker compose up -d`），或用 `npm ci && npm run build` 更新到最新代码。启动后可在日志里确认那行 `QQ Music API started`，其 `port` 字段就是实际监听端口。
+
+**Q：QQ 音乐二维码不弹 / 扫码登录失败 / cookie 无法使用？**
+A：通常是内置的 QQ 音乐 API 服务没起来——它一旦没监听 `qqMusicApiPort`（默认 3200）端口，机器人去取二维码就会拿到 `ECONNREFUSED 127.0.0.1:3200`，于是二维码不显示，登录和 cookie 也全失效。先看日志里 QQ API 的启动报错：
+- 报 `ERR_REQUIRE_ESM`：装到了不兼容的 `@sansenjian/qq-music-api` 版本。本项目把它锁在 **`~2.4.0`**（需要 **Node ≥ 20.17 / 22.9**）；务必用 `npm ci` 或 `npm install` 让版本与锁文件一致，**不要**手动 `npm update` 把它升级或降级到不兼容的中间版本（2.3.0/2.3.1 是纯 ESM、会触发此错）。
+- 报 Node 版本不满足：升级 Node 到 ≥ 20.17，或将该依赖降到 `~2.2.10`（无此 Node 要求）后重装。
+修好版本后重新 `npm install && npm run build` 并重启即可。
 
 **Q：播放歌曲时报 FFmpeg EACCES 错误？**
 A：`ffmpeg-static` 内置的 FFmpeg 二进制文件缺少执行权限。程序已自动尝试修复，如果仍然失败，请手动执行：
@@ -628,9 +884,104 @@ A：本项目内置 `/login` 限流（每 IP 每分钟 5 次），但生产部
 
 > 完整历史请查看 [git log](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/commits/main) 或 [Releases](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/releases)。这里只列出重要变更和面向用户的破坏性改动。
 
-### 最新版本
+### 最新版本 — v1.13.0：本地视频上传播放 / 头像上传时机
 
-**功能增强：细粒度权限 / 本地收藏 / 本地音频上传 / 专属链接 / 自动暂停 / QQ 雷达 FM**
+处理了 2 个社区反馈的 issue。**没有配置变化，升级无需任何操作**；原有的本地音频上传行为完全不变。
+
+**本地视频上传播放（[#149](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/149)，[PR #151](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/151)，感谢 [@LadenceE](https://github.com/LadenceE)）**
+
+- 搜索页的本地上传现在也收**视频文件**：mp4 / mov / avi / mkv / flv / wmv / m4v / mpg / mpeg / 3gp / ts / m2ts / ogv。上传后当普通歌曲用——直接播放、下一首播放、加入队列都一样。
+- 视频**只保留音轨**：上传后立刻把音频流原样搬进一个音频容器（不重编码、无损），再删掉原视频。720p 素材实测落盘只剩原文件的 14%，不然十几个视频就把 5 GiB 的上传目录配额占满了。
+- 没有音轨的视频会在**上传时**就被拒绝并说明原因，而不是排进队列后静默跳过。
+- 单文件上限从 200 MB 提到 **500 MB**；超限时的报错从 Express 默认的 HTML 错误页（带堆栈和服务器绝对路径）换成正常的中文提示，浏览器端也会在开传前就拦下超大文件。
+- 上传进度按文件显示百分比，传完切到「服务端处理中」——视频比音频大得多，原先那句静止的「正在上传」看着像卡死。
+- 说明：这里做的是「把你本地磁盘上的文件传上来播放」。让机器人直接读取**服务器**磁盘上任意路径的文件没有做——那等于开一个全盘任意文件读取的口子，而「播放服务器上已有的媒体库」用 Jellyfin 音源即可。
+
+**初始化阶段不再发起注定失败的头像上传（[#148](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/148)，[PR #150](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/150)，感谢 [@shenmu-rua](https://github.com/shenmu-rua)）**
+
+- 机器人构造阶段读出已保存的自定义头像后会立刻发起文件传输，但那时 TeamSpeak 还没连上，这次传输必定失败。现在构造阶段只把头像数据装入内存，实际上传交给连接成功后的 `onConnect()`。
+- **影响范围说明**：头像本身一直是能正常显示的（连接成功后本来就会重新应用一次），所以这不是「头像丢了」。真正的代价是每次启动 / 重启都会多一次注定失败的请求和一条 `Profile update failed` 警告日志——现在没有了。
+- 顺带修掉一个边角：头像文件写到一半崩溃会留下 0 字节文件，原先这会再触发两个同样注定失败的请求。
+
+### v1.12.0：网站图标 / 移动端交互 / 安装脚本按 ABI 自愈
+
+一次性处理了 6 个社区反馈的 issue。**没有配置变化，升级无需任何操作**；`!play id:<id>` 等旧写法全部继续可用。
+
+**安装脚本按 Node ABI 校验并自动修复（[#140](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/140)，[PR #147](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/147)，感谢 [@zbn297427669](https://github.com/zbn297427669)）**
+
+- 换过 Node 大版本后启动报 `NODE_MODULE_VERSION 137 ... requires 127`、或提示找不到 `opus.node` 的问题已修复。原生模块只能在编译它的 Node ABI 上加载，而旧脚本只检查「文件存在且够大」，会把给另一个 Node 版本编译的二进制原样留下。
+- 现在安装脚本会在子进程里真的加载一遍每个原生模块，不匹配就按当前 ABI 重新安装；替换过程先备份再原子替换，任何一步失败都会把原文件逐字节还原，不会让环境变得更糟。被中断留下的备份，下次运行自动认领回来。
+- 必需模块失败会**中止安装并返回非零**，不再出现「setup 显示成功、start 才爆炸」；下载进度实时显示在控制台，不再让人以为卡死。
+- `start.bat` 和 `npm start` 启动前会预检，直接说清楚哪个模块对不上、分别是哪个 ABI、怎么修。
+- 顺带修掉一个会**静默丢掉 ffmpeg** 的问题：源码编译会阻塞事件循环，把同时进行的 80MB ffmpeg 下载误判为超时，而 ffmpeg 是可选模块，于是安装照样报告成功、用户却放不出任何声音。三个模块改为串行处理。
+- Node 版本要求按依赖真实下限判断（20.19+ / 22.12+），推荐 20 或 22 LTS；更新的大版本不阻止，只提示可能需要源码编译。
+
+**随机模式下 `!pn` 真正下一首播放（[#141](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/141)，[PR #144](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/144)，感谢 [@XuVIIJay](https://github.com/XuVIIJay)）**
+
+- 随机 / 随机循环下 `!pn`（以及 WebUI 的「下一首播放」）插入的歌只是和其他歌一样等着被随机抽中，机器人却回复「Up next」。现在会真的下一首播放，连续插入多首时的顺序与队列里显示的一致。
+- 同时修掉两个相关问题：插入或删除队列中的歌之后，待播位置可能指向另一首歌；删得多了甚至会让播放**静默停止**。
+
+**WebUI 站点图标与移动端交互（[#142](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/142) / [#143](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/143) / [#138](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/138)，[PR #146](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/146)，感谢 [@XuVIIJay](https://github.com/XuVIIJay) 与 [@hak5ya](https://github.com/hak5ya)）**
+
+- 新增站点图标：收藏网页、移动端添加到主屏幕都会显示图标（含 iOS 与 Android 适配）。
+- 移动端迷你播放器的进度条现在**可以点按和拖动调节进度**，触摸区域也放大到可用尺寸，拖动时不会被自动跳转到歌词页。
+- 移动端**单击歌曲行即可播放**（桌面端双击行为不变）；队列抽屉里的歌曲行同样支持，其移除按钮在触屏下不再是「看不见但点得到」。
+- QQ 扫码登录的提示改为「请使用手机QQ扫码」——那是 QQ 账号二维码，用 QQ音乐 APP 扫不出来。
+
+**`!play id <id>` 与其他命令语法统一（[#139](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/139)，[PR #145](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/145)，感谢 [@hak5ya](https://github.com/hak5ya)）**
+
+- 按 id 播放现在可以写成 `!play id <id>`，和其他命令的 `<命令> <子命令> <参数>` 形式一致；`!add` / `!playnext` 同样适用。
+- **旧写法 `!play id:<id>` 继续支持**。空格写法只在参数确实像 id 时生效，普通搜索和粘贴链接的行为不受影响。
+
+### v1.11.2 — 可配置语音闪避
+
+- 检测频道内其他人说话时平滑降低音乐音量，停止后平滑恢复；默认关闭，可在设置页启用并调节说话时保留的音量比例（[#136](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/136)，[PR #137](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/137)）。
+
+### v1.11.1：修复 `!help` 触发机器人自动点歌
+
+**丢弃自回显消息（[PR #135](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/135)，感谢 [@EvolvedGhost](https://github.com/EvolvedGhost)）**
+
+- 修复输入 `!help` 后机器人会自己点一首歌开始播放的问题：帮助文本超过 TeamSpeak 单条消息上限被分段发送，而 TeamSpeak 会把 bot 自己发到频道的消息回推给它自己，第二段恰好以 `!artist ...` 开头，被误当作新命令解析执行。
+- 现在在协议层丢弃发送者为机器人自身的消息，机器人不再响应任何自己发出的文本，所有超长分段输出均安全。无配置变化，升级无需任何操作。
+
+### v1.11.0 — 播放清单持久化 / 设置保留 / 自定义默认音源
+
+**保存/加载播放清单 + 队列持久化（[#119](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/119)）——三项开关均默认关闭，升级无行为变化**
+
+- **保存/加载播放清单（`savedQueuesEnabled`，默认关闭，管理员开关）**：开启后，可在网页「已存队列」页或聊天命令保存当前队列为清单、随时**替换**加载或**追加**到队列末尾。网页保存可选「共享」（否则私有到当前用户）；聊天命令始终进入共享清单。新增聊天命令 `!save <名称>` / `!load [-a] <名称>` / `!queues`（未启用时回复「此功能未启用」）。上限：每个所有者 ≤ 50 份清单，每份 ≤ 1000 首。
+- **重启后自动恢复并继续播放队列**（同由 `savedQueuesEnabled` 门控）：机器人连接后会恢复上次的队列并继续播放。**说明**：只能从当前曲目的**开头**恢复（不记忆播放进度，链接重新解析）；**Spotify 恢复为尽力而为**（依赖 sidecar 重新可用），其他音源可靠。
+- **单曲直接播放不清空队列（`playKeepsQueue`，默认关闭，独立开关）**：开启后，直接播放单曲会插入到当前歌曲之后并立即播放、播完继续原队列，而不是清空整个队列。仅影响单曲的「直接播放」；歌单 / 专辑 / 电台仍会替换队列。
+- 三项均在 设置 → 行为设置 中开关，保存即时生效，无需重启。
+
+**重启后保留播放设置（[#125](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/125)）**
+
+- **音量与播放模式**现按机器人持久化到数据库（`bot_instances` 表新增 `volume` / `play_mode` 列，自动迁移），**各平台音质**持久化到 `config.json` 的 `audioQuality` 字段；重启后自动恢复，不再需要每次手动重调。
+- 聊天命令、WebUI、REST 三种入口的改动都会落盘；`!fm` / `!artist` 的临时随机 / 循环切换**不会**覆盖你用 `!mode` 显式保存的偏好。播放队列、当前歌曲与播放进度仍不持久化（队列恢复见上方 `savedQueuesEnabled`）。
+
+**自定义默认音源（[#126](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/126)）**
+
+- `config.json` 新增可选字段 `defaultPlatform`，或在 **设置 → 默认音源** 下拉选择：设定后，不带平台标志的 `!play` / `!search` / `!fm` 走你指定的音源（例如设为 `bilibili` 后点播 B 站视频音乐无需每次加 `-b`）。
+- 留空 / `null` 恢复原有固定优先级（网易云 → QQ → 酷狗 → Jellyfin → B 站 → YouTube）；若指定音源未启用或值非法，自动回退到优先级，保存即时生效、无需重启。
+
+**修复与加固**
+
+- **QQ 音乐 API 端口对齐（[#122](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/122)）**：内嵌 QQ 音乐 API sidecar 现在保证绑定到 `qqMusicApiPort`（与客户端请求端口一致），启动日志改为打印**实际绑定端口**便于排查。若你在旧 `latest` 镜像上遇到「日志里 baseURL 是 3200、服务却在 3300」导致二维码不显示，请 `docker compose pull` 重新拉取镜像。
+- **WebUI 不再被搜索引擎收录（[#128](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/128)）**：所有响应加 `X-Robots-Tag: noindex, nofollow`、新增 `/robots.txt`（Disallow 全站）、页面加 `robots` meta 标签。⚠️ 这只是阻止**收录**，不是访问控制——公网部署请务必依赖登录鉴权与反向代理，并且不要把自己的 WebUI 链接发到公开网页。
+- **`.gitignore` 补充 `.claude/`（[#127](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/127)，感谢 [@ItsEricRao](https://github.com/ItsEricRao)）**：本地 Claude Code 配置不再被误提交（已从版本库取消跟踪，本地文件不受影响）。
+
+### v1.10.1 — Jellyfin 可选音源
+
+**Jellyfin 集成（[PR #123](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/123)，由 [@ItsEricRao](https://github.com/ItsEricRao) 贡献；随后调整为可选音源）**
+
+- **Jellyfin 音源（可选，默认关闭）**：连接自建 [Jellyfin](https://jellyfin.org/) 服务器作为额外音源——搜索（歌曲 / 专辑 / 歌单，支持翻页）、懒解析直传播放、同步歌词、收藏 Instant Mix 电台（`!fm -j`）、首页「最近添加 / 播放最多 / 收藏 / 流派」区块、播放进度回报（PlayCount / 播放状态）。账号密码或 API Key 两种认证，在 设置 → Jellyfin 音乐库 打开「启用 Jellyfin 音源」即可，保存即时生效。详见 [可选：Jellyfin 音源](#可选jellyfin-音源)。
+- **enabledProviders 音源开关**：`config.json` 新增 `enabledProviders` 字段，默认 `["netease", "qq", "bilibili", "youtube", "kugou"]`——在线音源保持默认启用，**从旧版本升级无行为变化**；列表外的音源在聊天命令 / REST / WebUI 中一律不可用，网易云 / QQ 停用时其内嵌 API 服务（端口 3001 / 3200）不再启动。
+- **新增 `-j`（Jellyfin）与 `-n`（网易云）平台标志**；不带标志的 `!play` / `!search` / `!fm` 等走固定优先级中第一个已启用的音源（默认配置下即网易云，行为与旧版一致）。
+- ⚠️ **v1.10.0 初版曾短暂把默认音源设为 Jellyfin-only，现已回退**。若你在该版本保存过设置导致 `config.json` 中为 `"enabledProviders": ["jellyfin"]`，请手动把在线音源加回（详见 [更新升级](#关于-enabledproviders-音源开关v1100-起)）。
+- **QQ 按 ID 播放空歌名修复**（[PR #124](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/124)，感谢 [@Slldyd2077](https://github.com/Slldyd2077)）：按 ID 播放 QQ 歌曲时回填歌曲元数据，TS 端不再显示空歌名。
+
+### v1.9.0 及更早
+
+**功能增强：Spotify 音源（实验性）/ 搜索结果翻页 / 细粒度权限 / 本地收藏 / 本地音频上传 / 专属链接 / 自动暂停 / QQ 雷达 FM**
 
 - **细粒度账号权限**（叠加在 admin / member 之上）：管理员可为每个成员勾选 5 项能力（`player.control` / `player.queue` / `bot.manage` / `platform.auth` / `quality`）和按机器人授权白名单；所有变更路由由后端 `requirePermission` / `requireBotAccess` 中间件逐请求强制校验，未授权返回 403，未授权的机器人对成员不可见（列表过滤，无 403-vs-404 枚举泄漏）。已有成员经一次性迁移获得全部能力，新成员默认基础能力。
 - **本地收藏歌单**：按用户存储的收藏（`favorite_playlists` 表 + `/api/favorites`），首页 / 搜索 / 歌单页一键收藏，跨设备同步。
@@ -638,9 +989,12 @@ A：本项目内置 `/login` 限流（每 IP 每分钟 5 次），但生产部
 - **专属链接（单机器人锁定）**：`/bot/<id>` 打开时锁定到单台机器人，`?bot=<id>` 随刷新保持；与权限白名单组合，机器人下拉只显示"作用域 ∩ 可控"的机器人。
 - **频道无人时自动暂停**：机器人所在频道清空时暂停、有人加入时恢复（区分用户手动暂停，不会误恢复）；可在 设置 → 行为设置 开关（默认关闭）。占用检测在 `clientlist` 查询失败时按"未知"处理而非"无人"，避免有人在听时被误暂停。
 - **QQ 音乐雷达 / 私人 FM**：`!fm -q` 或 WebUI 启动 QQ 雷达推荐流（失败回退"猜你喜欢"），FM 自动续播现支持任意平台。
+- **#112 Spotify 音源（实验性）**：新增 Spotify 作为可选音源，默认关闭、需 Premium + 自建开发者应用（PKCE，无需 Client Secret）。采用混合 librespot 后端（Linux/Docker 用 go-librespot，Windows 用 Rust librespot），元数据走 Spotify Web API，可与现有音源混排入队。为 ToS 灰色地带的实验特性，详见 [Spotify 音源（实验性）](#spotify-音源实验性)。
+- **#115 搜索结果翻页**：WebUI 搜索现按来源、按分类（歌曲 / 歌单 / 专辑）提供「加载更多」，服务端新增 `offset` 分页，不再固定只返回首页 20 首 / 10 个歌单 / 10 张专辑。
 
 **Bug 修复**
 
+- **#116 `!lyrics` 只显示开头几行**：聊天命令曾把歌词截断为前 10 行，且长消息未分片会触及 TeamSpeak 单条约 1 KB 上限。现发送完整歌词，并按 UTF-8 字节安全地分割成多条消息（长回复通用分片，不再截断）。
 - **#86 config.json 未在首次运行生成**：配置文件改放到持久化的 `data/config.json`（旧版写在项目根目录，不在 Docker 卷内，导致重启丢失、手动编辑不生效）；升级时自动把根目录旧配置迁移到 `data/` 并保留你的设置。
 - **#89 B站长音频约 16 分钟被暂停且无法继续**：ffmpeg 增加 `-reconnect_at_eof`（B站 CDN 会在 token/会话到期时提前关闭连接造成 EOF），并新增"远离结尾的卡死看门狗"——彻底卡死的流会自动推进到下一首而不是永久静音。
 - **#84 音量曲线不顺滑**：0–100 改为连续单调曲线 `0.2x + 0.8x^8`（消除 80–99 的"死区"与 100 处的突跳，满响度仍保留在 100）。
@@ -655,6 +1009,7 @@ A：本项目内置 `/login` 限流（每 IP 每分钟 5 次），但生产部
 - **会话存储**：服务端 SQLite 表 `sessions`，存储 sha256(token)；浏览器只持有原始 token cookie。7 天 TTL，每小时滚动续期。同账号最多 10 个并发会话（超出剔除最旧）。
 - **登录限流**：每 IP 每分钟 5 次 `/login` + 3 次 `/setup`，命中返回 429 + `Retry-After`。
 - **CSRF & 安全头**：所有 mutating 请求强制 `Origin`/`Referer` 同源；响应携带 `X-Frame-Options: DENY` 和 `Content-Security-Policy: frame-ancestors 'none'`（防点击劫持）。
+- **搜索引擎隐身（防止实例被收录，issue #128）**：为避免部署实例的 WebUI 被搜索引擎收录、被陌生人搜到控制页，采用纵深防御——所有响应携带 `X-Robots-Tag: noindex, nofollow`，`/robots.txt` 返回 `User-agent: * / Disallow: /`，`index.html` 内置 `<meta name="robots" content="noindex, nofollow">`（专属链接 `/bot/<id>` 等所有页面同样覆盖）。这些只阻止「被索引」，不是访问控制——**请不要把自己的 WebUI 链接发到公开网页 / 论坛 / 聊天群**，真正的防护来自登录鉴权与反向代理。
 - **配置变更**：反向代理部署务必 `"trustProxy": true`（详见 [反向代理部署注意事项](#反向代理部署注意事项)）。`config.adminGroups` 现已启用，用于限制管理类聊天命令只能由指定 TeamSpeak 服务器组运行（为空 = 不限制，详见 [TeamSpeak 命令权限](#teamspeak-命令权限管理类命令限制)）；`config.adminPassword` 仍为旧版预留字段，保留以兼容旧 `config.json`，当前未使用。
 
 ### v0.x — Bot Profile 自动更新与协议层升级
@@ -727,6 +1082,7 @@ A：本项目内置 `/login` 限流（每 IP 每分钟 5 次），但生产部
 - **初始 TS3/TS6 双协议支持**：自动协议检测（TS3 port 10011 vs TS6 port 10080）、TS6 HTTP Query 客户端、数据库持久化 `serverProtocol` / `ts6ApiKey`。
 - **多机器人架构**：支持同一进程中运行多个机器人实例，独立队列、进度、音量；WebUI 一键切换。
 - **网易云 / QQ 音乐 / 哔哩哔哩**：三平台原生音源，QR 码登录，Cookie 持久化。
+- **酷狗音乐音源**：第四个原生音源（直连 API，无 npm 依赖 / 无内嵌服务），覆盖搜索 / 播放 / KRC 歌词 / 专辑 / QR 登录，登录后支持每日推荐 / 推荐歌单 / 我的歌单 / 私人电台与歌曲封面。
 - **Docker & systemd 部署**：一键部署脚本，数据卷持久化，自动重启支持。
 
 ## 致谢
@@ -735,6 +1091,8 @@ A：本项目内置 `/login` 限流（每 IP 每分钟 5 次），但生产部
 
 | 项目 | 说明 |
 |------|------|
+| [Jellyfin](https://github.com/jellyfin/jellyfin) | 自由软件媒体服务器（本项目的可选自建音源） |
+| [ItsEricRao](https://github.com/ItsEricRao) | Jellyfin 音源集成贡献者（[PR #123](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/pull/123)） |
 | [yichen11818/NeteaseTSBot](https://github.com/yichen11818/NeteaseTSBot) | TS6 协议兼容参考（vendored tsproto 补丁） |
 | [Splamy/TS3AudioBot](https://github.com/Splamy/TS3AudioBot) | 优秀的 TeamSpeak 音频机器人框架 |
 | [TS3AudioBot-BiliBiliPlugin](https://github.com/xxmod/TS3AudioBot-BiliBiliPlugin) | 提供插件开发参考 |
@@ -747,6 +1105,7 @@ A：本项目内置 `/login` 限流（每 IP 每分钟 5 次），但生产部
 | [@sansenjian/qq-music-api](https://github.com/sansenjian/qq-music-api) | QQ 音乐 API 活跃维护版本 |
 | [@honeybbq/teamspeak-client](https://www.npmjs.com/package/@honeybbq/teamspeak-client) | TS3 完整客户端协议实现 |
 | [bilibili-API-collect](https://github.com/SocialSisterYi/bilibili-API-collect) | 哔哩哔哩 API 文档 |
+| [MakcRe/KuGouMusicApi](https://github.com/MakcRe/KuGouMusicApi) | 酷狗音乐 API 参考（请求签名 / KRC 歌词解码 / 设备注册移植来源，MIT 许可） |
 
 ## 开源许可
 

docs/superpowers/plans/2026-07-03-spotify-stage4-polish-docs.md

@@ -0,0 +1,520 @@
+# Spotify Source — Stage 4 (Polish, Config UI, Docs) Implementation Plan
+
+> **For agentic workers:** REQUIRED SUB-SKILL: Use superpowers:subagent-driven-development to implement this plan task-by-task. Steps use checkbox (`- [ ]`) syntax for tracking.
+
+**Goal:** Complete the Spotify source's last mile — make it user-configurable and user-authorizable from the web UI, document it (with the required safety warnings), and land the deferred OAuth-robustness hardening.
+
+**Architecture:** The Stage-3 OAuth endpoints (`/api/spotify/{login,callback,status}`) and the single shared `SpotifyOAuth` already exist but are unreachable from the UI. Stage 4 adds: (1) a `spotify` block to the `/api/bot/settings` config API (secret masked); (2) a resolved-backend indicator on `/status`; (3) OAuth refresh/verifier hardening; (4) the approved Settings "Connect Spotify" card (spec §8); (5) the README Spotify section (spec §11/§12). Deferred (documented, NOT built this stage): runtime binary auto-download, connect play-not-reflected diagnostics, extra watchdog.
+
+**Tech Stack:** TypeScript (ESM, `.js` specifiers), Express, Vitest (root config also runs `web/src/**/*.test.ts` — stores/composables only; there is NO `.vue` component-test harness), Vue 3 + `<script setup>` + Pinia, `vue-tsc` (web build gate).
+
+## Global Constraints
+
+- **Safe-by-default (spec §2/§7):** Spotify stays inert unless `enabled` AND authorized AND a resolvable binary. Nothing in this stage may change behavior when `spotify.enabled === false`.
+- **Never expose secrets (spec §2/§7):** `clientSecret` is the operator's own value. The config GET API MUST NOT return the raw `clientSecret` — return only a boolean `hasClientSecret`. POST overwrites `clientSecret` only when a non-empty string is supplied (blank/omitted = unchanged). No bundled credentials, no shared Developer app.
+- **Permissions:** config writes gated by `requirePermission("bot.manage")`; reads by `requireNotGuest`; the OAuth login card is additionally shown only to `can('platform.auth')` / admins — mirror the existing Settings gating.
+- **Validation mirrors `src/data/config.ts`:** `backend` ∈ `{"auto","go-librespot","librespot"}`; `bitrate` ∈ `{96,160,320}`; `deviceName` non-empty trimmed string (else keep prior); strings coerced/guarded. Reuse the exact value sets.
+- **Language:** README additions are in Chinese (repo is Chinese-only), matching existing heading style (`## 功能特性` etc.).
+- **Licensing (spec §9):** go-librespot is GPL-3.0 — the README must include its license note + a source offer; the bot ships NO binary (source-only Rust librespot; Linux-only go-librespot assets).
+- **Honesty:** live audio / Connect control / real OAuth round-trip remain NOT verifiable here (need Premium + real binaries + a real account). "Done" = unit-tested (mocked process/HTTP/FS), `tsc --noEmit` clean, `cd web && npm run build` clean, full suite green, reviewed. Never claim audio works.
+- **Branch:** all work on `feat/spotify-audio`. Do NOT create per-task branches.
+- **Full suite command:** `npx vitest run --no-file-parallelism` (avoids the users.test.ts bcrypt LOAD flake). Typecheck: `npx tsc --noEmit`. Web build: `cd web && npm run build`.
+
+---
+
+### Task 1: `/api/bot/settings` reads & writes the `spotify` block (secret masked)
+
+**Files:**
+- Modify: `src/web/api/bot.ts` (GET `/settings` response + POST `/settings` destructure/validate/echo)
+- Test: `src/web/api/bot.test.ts`
+
+**Interfaces:**
+- Consumes: `config.spotify: SpotifyConfig` (`{ enabled, backend, clientId, clientSecret, deviceName, bitrate }`), `saveConfig(configPath, config)`, `requirePermission("bot.manage")`, `requireNotGuest` — all already imported/used in this file.
+- Produces (new response shape on GET+POST, both add a `spotify` key):
+  ```ts
+  // masked view — NEVER includes clientSecret
+  spotify: {
+    enabled: boolean;
+    backend: "auto" | "go-librespot" | "librespot";
+    clientId: string;
+    deviceName: string;
+    bitrate: number;
+    hasClientSecret: boolean;   // whether a non-empty secret is stored
+  }
+  ```
+
+- [ ] **Step 1.1: Write failing tests.** Add to `src/web/api/bot.test.ts` (mirror the existing settings tests — reuse their app/harness + auth stubs). Cover:
+  1. GET `/api/bot/settings` includes a `spotify` object with `enabled/backend/clientId/deviceName/bitrate/hasClientSecret` and does NOT include a `clientSecret` key. With a stored secret, `hasClientSecret === true`; with `clientSecret: ""`, `false`.
+  2. POST `/api/bot/settings` with `{ spotify: { enabled: true, backend: "librespot", clientId: "cid", deviceName: "Dev", bitrate: 160 } }` updates all those fields and echoes the masked view; `saveConfig` called.
+  3. POST with `{ spotify: { backend: "bogus" } }` leaves `backend` unchanged (invalid rejected, not 400 for the whole request — partial-merge semantics like the other fields). Same for `bitrate: 999`.
+  4. POST with `{ spotify: { clientSecret: "newsecret" } }` sets the secret (assert via `hasClientSecret === true` in the echo AND that `config.spotify.clientSecret === "newsecret"`). POST with `{ spotify: { clientSecret: "" } }` does NOT overwrite an existing secret.
+  5. POST `/api/bot/settings` spotify write requires `bot.manage` (a member without it → 403; reuse the existing 403 test pattern).
+  6. An existing settings POST that omits `spotify` still works and does not touch `config.spotify` (no regression).
+
+- [ ] **Step 1.2: Run the tests — expect failure** (`npx vitest run src/web/api/bot.test.ts`): the `spotify` key is absent from responses.
+
+- [ ] **Step 1.3: Extend GET `/settings`.** Add the masked spotify view to the response object (both the GET at ~line 36 and the POST echo at ~line 103 — extract a local helper to avoid duplication):
+  ```ts
+  // near the top of createBotRouter, after other helpers:
+  const maskedSpotify = () => ({
+    enabled: config.spotify.enabled,
+    backend: config.spotify.backend,
+    clientId: config.spotify.clientId,
+    deviceName: config.spotify.deviceName,
+    bitrate: config.spotify.bitrate,
+    hasClientSecret: config.spotify.clientSecret.length > 0,
+  });
+  ```
+  Add `spotify: maskedSpotify(),` to BOTH the GET response and the POST echo object.
+
+- [ ] **Step 1.4: Handle `spotify` in POST `/settings`.** Add `spotify` to the destructure and a partial-merge block (mirror config.ts validation). Place before `saveConfig(...)`:
+  ```ts
+  const VALID_BACKENDS = ["auto", "go-librespot", "librespot"] as const;
+  const VALID_BITRATES = [96, 160, 320];
+  const sp = req.body?.spotify;
+  if (sp && typeof sp === "object") {
+    const t = config.spotify;
+    if (typeof sp.enabled === "boolean") t.enabled = sp.enabled;
+    if (typeof sp.backend === "string" && (VALID_BACKENDS as readonly string[]).includes(sp.backend)) {
+      t.backend = sp.backend as SpotifyConfig["backend"];
+    }
+    if (typeof sp.clientId === "string") t.clientId = sp.clientId;
+    // Secret is write-only + set-on-non-empty so a blank field never wipes it.
+    if (typeof sp.clientSecret === "string" && sp.clientSecret.length > 0) {
+      t.clientSecret = sp.clientSecret;
+    }
+    if (typeof sp.deviceName === "string" && sp.deviceName.trim().length > 0) {
+      t.deviceName = sp.deviceName.trim();
+    }
+    if (typeof sp.bitrate === "number" && VALID_BITRATES.includes(sp.bitrate)) {
+      t.bitrate = sp.bitrate;
+    }
+  }
+  ```
+  Add the type import if not present: `import type { SpotifyConfig } from "../../data/config.js";`.
+
+- [ ] **Step 1.5: Run tests — expect pass** (`npx vitest run src/web/api/bot.test.ts`). Then `npx tsc --noEmit` clean.
+
+- [ ] **Step 1.6: Commit.**
+  ```bash
+  git add src/web/api/bot.ts src/web/api/bot.test.ts
+  git commit -m "feat(spotify): expose spotify config on /api/bot/settings (secret masked) [S4.1]"
+  ```
+
+---
+
+### Task 2: `/api/spotify/status` reports the RESOLVED backend + binary availability (D11)
+
+**Files:**
+- Create: `src/music/spotify/backend-select.ts` (pure resolver) + `src/music/spotify/backend-select.test.ts`
+- Modify: `src/music/spotify/controller.ts` (delegate `chooseBackend` to the resolver)
+- Modify: `src/web/api/spotify.ts` (`/status` shape + `getBackendInfo` type)
+- Modify: `src/web/server.ts` (`getBackendInfo` computes the resolved kind)
+- Modify: `src/web/api/spotify.test.ts` (update the `/status` shape assertion)
+
+**Interfaces:**
+- Produces:
+  ```ts
+  // backend-select.ts
+  export type SpotifyBackendKind = "go-librespot" | "librespot";
+  export function resolveSpotifyBackendKind(
+    backend: "auto" | "go-librespot" | "librespot",
+    goPresent: boolean,
+    rustPresent: boolean,
+  ): SpotifyBackendKind | null;
+  // spotify.ts getBackendInfo now returns:
+  { backend: string; deviceName: string; binaryAvailable: boolean }
+  // /status response now:
+  { authorized: boolean; backend: string; deviceName: string; binaryAvailable: boolean }
+  ```
+- Note: `SpotifyBackendKind` currently lives in `controller.ts`. Move the canonical definition to `backend-select.ts` and re-export it from `controller.ts` (`export type { SpotifyBackendKind } from "./backend-select.js";`) so existing importers are unaffected.
+
+- [ ] **Step 2.1: Write failing resolver tests** `src/music/spotify/backend-select.test.ts` — the same 8-case matrix S3.5 used, but against the pure function:
+  ```ts
+  import { describe, it, expect } from "vitest";
+  import { resolveSpotifyBackendKind as pick } from "./backend-select.js";
+  describe("resolveSpotifyBackendKind", () => {
+    it("auto: go present -> go-librespot", () => expect(pick("auto", true, true)).toBe("go-librespot"));
+    it("auto: go absent, rust present -> librespot", () => expect(pick("auto", false, true)).toBe("librespot"));
+    it("auto: neither -> null", () => expect(pick("auto", false, false)).toBeNull());
+    it("go-librespot: present -> go-librespot", () => expect(pick("go-librespot", true, true)).toBe("go-librespot"));
+    it("go-librespot: absent -> null even if rust present", () => expect(pick("go-librespot", false, true)).toBeNull());
+    it("librespot: present -> librespot", () => expect(pick("librespot", true, true)).toBe("librespot"));
+    it("librespot: absent -> null even if go present", () => expect(pick("librespot", true, false)).toBeNull());
+    it("auto default fallthrough matches auto", () => expect(pick("auto", true, false)).toBe("go-librespot"));
+  });
+  ```
+
+- [ ] **Step 2.2: Run — expect failure** (module missing).
+
+- [ ] **Step 2.3: Create the resolver** `src/music/spotify/backend-select.ts`:
+  ```ts
+  /** Which concrete backend runs for a given config + host binary availability. */
+  export type SpotifyBackendKind = "go-librespot" | "librespot";
+
+  /**
+   * Pure backend selection shared by SpotifyController.chooseBackend() (per-bot)
+   * and the web /status endpoint (process-wide). Booleans in, no IO — the caller
+   * supplies platform+binary presence.
+   */
+  export function resolveSpotifyBackendKind(
+    backend: "auto" | "go-librespot" | "librespot",
+    goPresent: boolean,
+    rustPresent: boolean,
+  ): SpotifyBackendKind | null {
+    switch (backend) {
+      case "go-librespot":
+        return goPresent ? "go-librespot" : null;
+      case "librespot":
+        return rustPresent ? "librespot" : null;
+      case "auto":
+      default:
+        if (goPresent) return "go-librespot";
+        if (rustPresent) return "librespot";
+        return null;
+    }
+  }
+  ```
+
+- [ ] **Step 2.4: Run resolver tests — expect pass.**
+
+- [ ] **Step 2.5: Delegate from the controller.** In `controller.ts`, import the type+resolver **with a local binding** (a bare `export … from` re-export does NOT create a local name, and `SpotifyBackendKind` is still referenced locally at `chooseBackend()`'s return type and `buildBackend(kind: SpotifyBackendKind)` → would fail TS2304). Use:
+  ```ts
+  import { resolveSpotifyBackendKind, type SpotifyBackendKind } from "./backend-select.js";
+  export type { SpotifyBackendKind };   // keep the name exported for existing importers
+  // ...
+  chooseBackend(): SpotifyBackendKind | null {
+    return resolveSpotifyBackendKind(this.config.backend, this.goPresent(), this.rustPresent());
+  }
+  ```
+  Remove the old inline `switch` body and the standalone `export type SpotifyBackendKind = "go-librespot" | "librespot";` line. Keep `goPresent()/rustPresent()` as-is. Run `npx vitest run src/music/spotify/controller.test.ts` — the S3.5 matrix + auth-gate specs MUST still pass unchanged.
+
+- [ ] **Step 2.6: Update `/status`** in `src/web/api/spotify.ts` — extend the `getBackendInfo` type and the response:
+  ```ts
+  getBackendInfo: () => { backend: string; deviceName: string; binaryAvailable: boolean };
+  // ...
+  router.get("/status", requireNotGuest, (_req, res) => {
+    const info = opts.getBackendInfo();
+    res.json({
+      authorized: oauth.isAuthorized(),
+      backend: info.backend,
+      deviceName: info.deviceName,
+      binaryAvailable: info.binaryAvailable,
+    });
+  });
+  ```
+
+- [ ] **Step 2.7: Compute the resolved kind in `server.ts`.** Replace the `getBackendInfo` closure (currently returns raw `config.spotify.backend`) with a resolver call using live probes. Add imports `import { resolveSpotifyBackendKind } from "../music/spotify/backend-select.js";` and `import { isGoLibrespotSupported, findGoLibrespot, isRustLibrespotSupported, findLibrespot } from "../music/spotify/binary.js";` and `import { existsSync } from "node:fs";` (verify existsSync isn't already imported):
+  ```ts
+  getBackendInfo: () => {
+    const goPresent = isGoLibrespotSupported() && existsSync(findGoLibrespot());
+    const rustPresent = isRustLibrespotSupported() && existsSync(findLibrespot());
+    const resolved = resolveSpotifyBackendKind(options.config.spotify.backend, goPresent, rustPresent);
+    return {
+      backend: resolved ?? "none",
+      deviceName: options.config.spotify.deviceName,
+      binaryAvailable: resolved !== null,
+    };
+  },
+  ```
+
+- [ ] **Step 2.8: Update the `/status` test** in `src/web/api/spotify.test.ts` — the existing `toEqual({ authorized, backend, deviceName })` must become `toEqual({ authorized, backend, deviceName, binaryAvailable })`; extend the fake `getBackendInfo` in that test to return `binaryAvailable`. This is THIS task's contract change; update only the status test.
+
+- [ ] **Step 2.9: Verify.** `npx vitest run src/music/spotify/backend-select.test.ts src/music/spotify/controller.test.ts src/web/api/spotify.test.ts` all pass; `npx tsc --noEmit` clean.
+
+- [ ] **Step 2.10: Commit.**
+  ```bash
+  git add src/music/spotify/backend-select.ts src/music/spotify/backend-select.test.ts src/music/spotify/controller.ts src/web/api/spotify.ts src/web/server.ts src/web/api/spotify.test.ts
+  git commit -m "feat(spotify): report resolved backend + binaryAvailable on /status; share backend resolver [S4.2]"
+  ```
+
+---
+
+### Task 3: OAuth robustness — in-flight refresh cache + verifier TTL/cap (D9)
+
+**Files:**
+- Modify: `src/music/spotify/spotify-oauth.ts`
+- Test: `src/music/spotify/spotify-oauth.test.ts`
+
+**Interfaces:**
+- Consumes: existing `SpotifyOAuthOptions.deps?: { http?: AxiosInstance }`. Extend deps with an optional clock for testability: `deps?: { http?: AxiosInstance; now?: () => number }`.
+- Produces: no public API change. Internals: `refreshInFlight: Promise<string|null> | null`; `pendingVerifiers: Map<string, { verifier: string; expiresAt: number }>`.
+
+- [ ] **Step 3.1: Write failing tests.** Add to `src/music/spotify/spotify-oauth.test.ts`:
+  1. **Concurrent refresh collapses to one POST.** Build with a fake `http` whose `post("/api/token")` returns a promise you resolve manually (a `Deferred`) or counts calls, and a MUTABLE fake store (`save()` persists, `load()` returns the last saved value) seeded with an expired token. Fire two `getAccessToken()` calls before the POST resolves; assert `http.post` called exactly ONCE and both awaited results equal the new access token.
+  2. **In-flight clears after settle.** Using the same mutable store + a mutable `now` (`let t=…; now=()=>t`), after test 1 resolves, advance `t` past the newly-saved `expiresAt` and call `getAccessToken()` again → a NEW POST fires (count → 2). (Requires `toTokens` on `this.now()` per Step 3.3.)
+  3. **Verifier TTL.** With injected mutable `now`, `buildAuthorizeUrl()` at t=0 (capture its `state`), advance `now` to TTL+1, then `handleCallback(code, state)` → returns false (expired) and the entry is gone.
+  4. **Verifier cap.** Call `buildAuthorizeUrl()` `VERIFIER_MAX + 1` times (capturing the FIRST `state`); assert **behaviorally** that `handleCallback(code, <first state>)` now returns false (evicted as oldest). Prefer this behavioral assertion over inspecting the private `pendingVerifiers` map (no `as any` cast). Use the injected `now` for all timing.
+
+- [ ] **Step 3.2: Run — expect failure.**
+
+- [ ] **Step 3.3: Add the clock + in-flight refresh.** In the constructor: `this.now = o.deps?.now ?? (() => Date.now());` (add `private now: () => number;`). Rewrite `getAccessToken()` + add the in-flight field:
+  ```ts
+  private refreshInFlight: Promise<string | null> | null = null;
+
+  async getAccessToken(): Promise<string | null> {
+    if (!this.clientId) return null;
+    const tokens = this.store.load();
+    if (!tokens?.refreshToken) return null;
+    if (tokens.accessToken && this.now() < tokens.expiresAt) return tokens.accessToken;
+    // Collapse concurrent refreshes: rotation makes a second in-flight refresh
+    // use a refresh token the first one already invalidated.
+    if (this.refreshInFlight) return this.refreshInFlight;
+    this.refreshInFlight = this.refresh(tokens).finally(() => {
+      this.refreshInFlight = null;
+    });
+    return this.refreshInFlight;
+  }
+  ```
+  Replace the `Date.now()` in `getAccessToken` (spotify-oauth.ts:188) with `this.now()`. **Also change `toTokens` (spotify-oauth.ts:~221) to compute `expiresAt` from `this.now()` instead of `Date.now()`** — this is REQUIRED for testability: if `toTokens` kept real `Date.now()` while `getAccessToken` used an injected fixed clock, a freshly-refreshed token's `expiresAt` would sit far in the injected past/future and the "subsequent call → new POST" test would be non-deterministic. With both on `this.now()`, the test drives a mutable `now` (e.g. `let t = 0; const now = () => t;`) and advances it past the new `expiresAt` to force the second refresh.
+
+- [ ] **Step 3.4: Add verifier TTL + cap.** Change the map type and the two touch points:
+  ```ts
+  private pendingVerifiers = new Map<string, { verifier: string; expiresAt: number }>();
+  private static readonly VERIFIER_TTL_MS = 10 * 60 * 1000;
+  private static readonly VERIFIER_MAX = 32;
+
+  private evictStaleVerifiers(): void {
+    const t = this.now();
+    for (const [state, e] of this.pendingVerifiers) {
+      if (e.expiresAt < t) this.pendingVerifiers.delete(state);
+    }
+    // Bound memory even if all are unexpired: drop oldest (insertion order).
+    while (this.pendingVerifiers.size >= SpotifyOAuth.VERIFIER_MAX) {
+      const oldest = this.pendingVerifiers.keys().next().value;
+      if (oldest === undefined) break;
+      this.pendingVerifiers.delete(oldest);
+    }
+  }
+  ```
+  In `buildAuthorizeUrl()`: call `this.evictStaleVerifiers();` before the set, then `this.pendingVerifiers.set(state, { verifier, expiresAt: this.now() + SpotifyOAuth.VERIFIER_TTL_MS });`.
+  In `handleCallback()`: replace the `get`:
+  ```ts
+  const entry = this.pendingVerifiers.get(state);
+  if (!entry || entry.expiresAt < this.now()) {
+    this.pendingVerifiers.delete(state);
+    return false;
+  }
+  const verifier = entry.verifier;
+  ```
+  (Keep the existing `finally { this.pendingVerifiers.delete(state); }`.)
+
+- [ ] **Step 3.5: Run tests — expect pass.** Then `npx vitest run src/music/spotify/spotify-oauth.test.ts` (all, incl. prior S3.2 tests) + `npx tsc --noEmit` clean.
+
+- [ ] **Step 3.6: Commit.**
+  ```bash
+  git add src/music/spotify/spotify-oauth.ts src/music/spotify/spotify-oauth.test.ts
+  git commit -m "fix(spotify): collapse concurrent OAuth refresh + TTL/cap PKCE verifiers [S4.3]"
+  ```
+
+---
+
+### Task 4: Settings "Connect Spotify" card (spec §8)
+
+**Files:**
+- Create: `web/src/composables/useSpotifySettings.ts` (pure, testable logic) + `web/src/composables/useSpotifySettings.test.ts`
+- Modify: `web/src/views/Settings.vue` (add the card + wiring)
+
+**Interfaces (composable — the unit-tested surface):**
+```ts
+export interface SpotifyConfigForm {
+  enabled: boolean;
+  backend: "auto" | "go-librespot" | "librespot";
+  clientId: string;
+  clientSecret: string;   // blank means "unchanged"
+  deviceName: string;
+  bitrate: number;
+}
+export interface SpotifyStatus { authorized: boolean; backend: string; deviceName: string; binaryAvailable: boolean; }
+export const SPOTIFY_DISCLAIMER: string;                    // Chinese risk copy
+export function buildSpotifyPayload(f: SpotifyConfigForm): { spotify: Record<string, unknown> };  // omits clientSecret when blank
+export function parseSpotifyRedirect(search: string): "success" | "error" | null;  // from ?spotify=...
+export function statusSummary(s: SpotifyStatus | null, enabled: boolean): { label: string; tone: "ok" | "warn" | "off" };
+```
+
+- [ ] **Step 4.1: Write failing composable tests** `web/src/composables/useSpotifySettings.test.ts` (root vitest picks it up; import from `./useSpotifySettings.js` per the repo's ESM `.js` convention):
+  - `buildSpotifyPayload` includes `clientSecret` only when non-blank; always includes enabled/backend/clientId/deviceName/bitrate under a `spotify` key.
+  - `parseSpotifyRedirect("?spotify=success")==="success"`, `"?spotify=error"==="error"`, `"?x=1"===null`.
+  - `statusSummary(null, false)` → tone `"off"`; `statusSummary({authorized:false,binaryAvailable:false,...}, true)` → tone `"warn"`; `statusSummary({authorized:true,binaryAvailable:true,...}, true)` → tone `"ok"`.
+
+- [ ] **Step 4.2: Run — expect failure** (module missing).
+
+- [ ] **Step 4.3: Implement the composable** `web/src/composables/useSpotifySettings.ts`:
+  ```ts
+  export interface SpotifyConfigForm { enabled: boolean; backend: "auto" | "go-librespot" | "librespot"; clientId: string; clientSecret: string; deviceName: string; bitrate: number; }
+  export interface SpotifyStatus { authorized: boolean; backend: string; deviceName: string; binaryAvailable: boolean; }
+
+  // 实验性 · 灰色地带 · 需要 Premium · 使用你自己的开发者应用凭据
+  export const SPOTIFY_DISCLAIMER =
+    "实验性功能：通过 librespot 播放 Spotify 需要 Spotify Premium 账号，并使用你自己注册的 Spotify 开发者应用凭据。" +
+    "该方式处于 Spotify 服务条款的灰色地带，风险自负；默认关闭，不会内置任何共享凭据。";
+
+  export function buildSpotifyPayload(f: SpotifyConfigForm): { spotify: Record<string, unknown> } {
+    const spotify: Record<string, unknown> = {
+      enabled: f.enabled,
+      backend: f.backend,
+      clientId: f.clientId,
+      deviceName: f.deviceName,
+      bitrate: f.bitrate,
+    };
+    if (f.clientSecret && f.clientSecret.length > 0) spotify.clientSecret = f.clientSecret;
+    return { spotify };
+  }
+
+  export function parseSpotifyRedirect(search: string): "success" | "error" | null {
+    const v = new URLSearchParams(search).get("spotify");
+    return v === "success" || v === "error" ? v : null;
+  }
+
+  export function statusSummary(s: SpotifyStatus | null, enabled: boolean): { label: string; tone: "ok" | "warn" | "off" } {
+    if (!enabled) return { label: "已关闭", tone: "off" };
+    if (!s) return { label: "未知", tone: "warn" };
+    if (!s.binaryAvailable) return { label: "未检测到 librespot 可执行文件", tone: "warn" };
+    if (!s.authorized) return { label: "未授权（点击“连接 Spotify”登录）", tone: "warn" };
+    return { label: `已就绪 · 后端 ${s.backend}`, tone: "ok" };
+  }
+  ```
+
+- [ ] **Step 4.4: Run composable tests — expect pass.**
+
+- [ ] **Step 4.5: Add the card to `Settings.vue`.** Insert a new `.account-card`-style section in the settings surface, gated `v-if="can('platform.auth')"` (mirror the platform-login section). Follow the EXISTING patterns in this file:
+  - typed input + Save → mirror the idle-timeout input/saver (`Settings.vue` idle-timeout block + `saveIdleTimeout()` → `POST /api/bot/settings`);
+  - select group → mirror the quality button-group for `backend` and `bitrate`;
+  - toggle → mirror `localAudioEnabled` for `enabled`.
+  **Fields to render (all six):** the `enabled` toggle, `backend` group, `bitrate` group, a `clientId` text input, a `deviceName` text input, and a **Client Secret** field — a write-only password input (`type="password"`, `autocomplete="off"`), left BLANK on load with a "已设置 / 未设置" hint from `hasClientSecret`; a blank secret on Save means "unchanged" (never wipes). The Secret is §8-mandated — do not omit it.
+  Wiring (use `axios`, matching the file's other calls):
+  - **Load** on mount: `GET /api/bot/settings` → populate the form from `res.data.spotify` (leave `clientSecret` blank; show “已设置/未设置” from `hasClientSecret`); `GET /api/spotify/status` → status indicator via `statusSummary`.
+  - **Save**: `POST /api/bot/settings` with `buildSpotifyPayload(form)`; on success re-load status.
+  - **Connect**: `const { data } = await axios.get('/api/spotify/login'); window.location.href = data.url;` (guard errors → show message; a 403 means missing `platform.auth`).
+  - **Redirect handling**: on mount, `parseSpotifyRedirect(window.location.search)`; if `success`/`error`, show a toast/message and strip the param (e.g. `history.replaceState`). Reuse the file's existing notification/toast mechanism if present; otherwise a simple reactive message line.
+  - **Disclaimer**: render `SPOTIFY_DISCLAIMER` prominently in the card.
+  Keep the `<script setup>` logic thin — delegate payload/summary/redirect parsing to the composable (already tested). Do not add a `.vue` test (no harness).
+  - **Keep the two "spotify auth" concepts distinct:** the card's status comes ONLY from `/api/spotify/status` (playback OAuth `authorized`). Do NOT wire it to the player store's `authStatus.spotify`, which reflects `/api/auth/status?platform=spotify` (metadata Web-API `loggedIn`) — a different thing. Leave the player store untouched.
+  - **`vue-tsc` typing:** annotate the form as `reactive<SpotifyConfigForm>({...})` and the status as `ref<SpotifyStatus | null>(null)`; otherwise a button-group assignment (`form.backend = 'librespot'`) widens `backend` to `string` and the `null` init breaks the union passed into `buildSpotifyPayload`/`statusSummary` under `vue-tsc --noEmit`.
+  - **Hard order dependency:** `binaryAvailable` on `/api/spotify/status` exists only after Task 2 — execute this task AFTER Task 2.
+
+- [ ] **Step 4.6: Build gate.** `cd web && npm run build` → `vue-tsc --noEmit` clean + vite build succeeds. Then from root `npx vitest run web/src/composables/useSpotifySettings.test.ts` green.
+
+- [ ] **Step 4.7: Commit.**
+  ```bash
+  git add web/src/composables/useSpotifySettings.ts web/src/composables/useSpotifySettings.test.ts web/src/views/Settings.vue
+  git commit -m "feat(spotify): Connect-Spotify settings card (config + OAuth login + status) [S4.4]"
+  ```
+
+**Notes:** NOT e2e-verifiable (needs a real account/binary). Verified = composable unit tests + `vue-tsc` typecheck + build. The card only exposes config + a login trigger; it never displays the stored `clientSecret` (GET returns `hasClientSecret`, not the value).
+
+---
+
+### Task 5: README Spotify section (Chinese) — spec §9/§11/§12
+
+**Files:**
+- Modify: `README.md` (add a `## Spotify 音源（实验性）` section; add "Spotify" to the feature bullet if appropriate)
+
+**Content (required — write real prose, not placeholders):**
+- [ ] **Step 5.1:** Add a top-level section `## Spotify 音源（实验性）` covering, in Chinese:
+  1. **醒目警告框:** 实验性；需要 **Spotify Premium**；使用**你自己注册的 Spotify 开发者应用**（不内置任何共享凭据）；处于 Spotify 服务条款灰色地带，风险自负；**默认关闭**。
+  2. **工作原理（简述）:** 通过 librespot（Rust）/ go-librespot（Linux）作为独立进程解码 → PCM → ffmpeg 重采样到 48k → 走现有 Opus 发送管线。元数据来自 Spotify Web API。
+  3. **平台矩阵:** Windows → `librespot`(Rust)；Linux/Docker → `go-librespot`（可回退 `librespot`）；`auto` 自动选择（表格）。
+  4. **获取二进制:** Rust librespot 无预编译包 → `cargo install librespot` 或 scoop/choco，或将可执行文件放入项目 `bin/`（`bin/librespot.exe` / `bin/librespot`）。go-librespot 仅提供 Linux 资产（`github.com/devgianlu/go-librespot/releases`），放入 `bin/go-librespot` 或加入 PATH。
+  5. **注册开发者应用 + 回调:** 在 Spotify Developer Dashboard 建应用，取 Client ID，回调地址填 `http://127.0.0.1:<webPort>/api/spotify/callback`（与设置里的 Web 端口一致）；PKCE 不需要 Client Secret。
+  6. **启用步骤:** 设置页「连接 Spotify」卡片 → 填 Client ID、选后端、开启开关 → 保存 → 点「连接 Spotify」完成 OAuth 授权。
+  7. **许可与来源:** go-librespot 为 **GPL-3.0**，作为独立子进程调用（mere aggregation，不影响本项目许可）；附上其源码地址与许可说明（source offer）。
+  8. **故障排查:** 「未检测到 librespot」→ 检查 `bin/` 或 PATH；「未授权」→ 完成 OAuth；Windows 不支持 go-librespot（FIFO 仅限 POSIX）。
+- [ ] **Step 5.2:** Sanity-check the doc renders (headings consistent with existing `##` style; links valid). No code test.
+- [ ] **Step 5.3: Commit.**
+  ```bash
+  git add README.md
+  git commit -m "docs(spotify): README Spotify source section — setup, binaries, warnings, license [S4.5]"
+  ```
+
+---
+
+### Task 6: Rust Connect command retry/backoff (recovery/watchdog — spec §4.3/§13)
+
+**Rationale:** Spec §4.3 mandates "a watchdog + retry/backoff for device-visibility latency and command 202/404 flakiness"; §13 lists Rust Connect as the **top risk** (mitigation: retry/backoff + degrade-to-skipped). Stage 3 already landed the device-visibility watchdog (`waitForDevice()` bounded poll in `rust-librespot.ts`) and per-track device-absence → skip (`findDeviceByName`→null → `playTrack` false → BotInstance skips). The remaining, un-built piece is transient-failure retry/backoff on the Connect **mutating commands** — this task adds it while preserving C3.6 (never reject up the queue path; swallow on exhaustion).
+
+**Files:**
+- Modify: `src/music/spotify/connect-api.ts` (retry/backoff around the mutating PUTs; optional injected `sleep`/`logger`)
+- Modify: `src/music/spotify/controller.ts` (pass `this.logger` into the default `SpotifyConnectApi`)
+- Test: `src/music/spotify/connect-api.test.ts`
+
+**Interfaces:**
+- Consumes: existing `constructor(getToken: () => Promise<string|null>, deps?: { http?: AxiosInstance })`. **Extend deps** to `{ http?: AxiosInstance; sleep?: (ms: number) => Promise<void>; logger?: import("pino").Logger }` (all optional → source-compatible).
+- No public method signature change: `transfer/play/pause/resume/seek` stay `Promise<void>` and still swallow on final failure.
+
+- [ ] **Step 6.1: Write failing tests** in `src/music/spotify/connect-api.test.ts` (reuse the existing `getToken`/`http` injection pattern; inject a no-op `sleep: async () => {}` so no real timers run):
+  1. `play()` retries a transient 404 then succeeds: `http.put` rejects once with `{ response: { status: 404 } }` then resolves → assert `http.put` called TWICE, no throw.
+  2. `play()` exhausts on persistent 500: `http.put` always rejects `{ response: { status: 500 } }` → assert exactly `MAX_ATTEMPTS` calls, no throw (swallowed), and `logger.warn` called once (logger provided).
+  3. Non-transient (403) is NOT retried: reject `{ response: { status: 403 } }` → exactly ONE call, no throw.
+  4. `429` honors a **capped** `Retry-After`: reject once `{ response: { status: 429, headers: { "retry-after": "1" } } }` then resolve → `sleep` called with a bounded delay (≤ the cap) and 2 calls total.
+  5. `transfer()` uses the same retry path (one representative non-`play` mutator) — 404-then-success → 2 calls.
+
+- [ ] **Step 6.2: Confirm Red** (`npx vitest run src/music/spotify/connect-api.test.ts`).
+
+- [ ] **Step 6.3: Implement retry/backoff.** Add module constants + a private helper and route each mutating PUT through it:
+  ```ts
+  const TRANSIENT = new Set([404, 429, 500, 502, 503]);
+  const MAX_ATTEMPTS = 3;
+  const BASE_DELAY_MS = 150;
+  const MAX_DELAY_MS = 2_000;
+  // ...
+  private async mutateWithRetry(put: () => Promise<unknown>): Promise<void> {
+    for (let attempt = 1; attempt <= MAX_ATTEMPTS; attempt++) {
+      try {
+        await put();
+        return;
+      } catch (err: any) {
+        const status = err?.response?.status;
+        if (!TRANSIENT.has(status) || attempt === MAX_ATTEMPTS) {
+          // C3.6: never reject up the queue path — swallow, but surface once.
+          this.logger?.warn({ status }, "Spotify Connect command failed (exhausted/non-retryable)");
+          return;
+        }
+        let delay = Math.min(BASE_DELAY_MS * 2 ** (attempt - 1), MAX_DELAY_MS);
+        if (status === 429) {
+          const ra = Number(err?.response?.headers?.["retry-after"]);
+          if (Number.isFinite(ra) && ra > 0) delay = Math.min(ra * 1000, MAX_DELAY_MS);
+        }
+        await this.sleep(delay);
+      }
+    }
+  }
+  ```
+  In the constructor: `this.sleep = deps?.sleep ?? ((ms) => new Promise((r) => setTimeout(r, ms)));` and `this.logger = deps?.logger;`. Rewrite `transfer/play/pause/resume/seek` so their body becomes: guard `authHeaders()` as today (unauth → `return;`, no retry), then `await this.mutateWithRetry(() => this.http.put(<url>, <body>, { headers, ... }));`. Keep the exact URLs/bodies/params from the current methods.
+
+- [ ] **Step 6.4: Thread the logger from the controller.** In `controller.ts` where the default connect is built:
+  ```ts
+  this.connect = o.connect ?? new SpotifyConnectApi(() => this.oauth.getAccessToken(), { logger: this.logger });
+  ```
+  (`Logger` is already imported in controller.ts.) Injected-connect tests are unaffected.
+
+- [ ] **Step 6.5: Update any conflicting existing connect test.** The S3.3 (C3.6) tests assert mutating calls swallow errors. If any asserts a single `http.put` call on a *transient*-status rejection, it now expects `MAX_ATTEMPTS` — update ONLY that count (this task's contract change). Do NOT weaken the swallow/no-throw guarantees or the non-transient single-call behavior.
+
+- [ ] **Step 6.6: Verify.** `npx vitest run src/music/spotify/connect-api.test.ts src/music/spotify/controller.test.ts` all pass; `npx tsc --noEmit` clean.
+
+- [ ] **Step 6.7: Commit.**
+  ```bash
+  git add src/music/spotify/connect-api.ts src/music/spotify/connect-api.test.ts src/music/spotify/controller.ts
+  git commit -m "feat(spotify): retry/backoff on Connect commands (device-latency/flakiness watchdog) [S4.6]"
+  ```
+
+**Notes:** Bounded retry adds latency only on the (off-audio-path) control commands and only on transient failure; the injected `sleep` makes tests instant. Not e2e-verifiable (no real account). The `202`-accepted-but-not-effective case from §4.3 is NOT handled here (it needs post-command state verification, which the existing poll-based track-end already tolerates) — noted as a follow-up.
+
+---
+
+### Task 7: Stage 4 verification + whole-branch final review + finish
+
+**Files:** none (verification + review + branch finish).
+
+- [ ] **Step 7.1: Full verification.** `npx vitest run --no-file-parallelism` (all green), `npx tsc --noEmit` (clean), `cd web && npm run build` (clean). Record counts.
+- [ ] **Step 7.2: Whole-branch adversarial review.** Review the ENTIRE `feat/spotify-audio` branch (`git merge-base main HEAD`..HEAD) — Stages 2+3+4 — with a fan-out of finders across dimensions (lifecycle/teardown correctness, OAuth/token security + no-secret-leak, backend selection + gating, async races, error handling, test hygiene) and adversarial verification of each finding. Dispatch ONE fix subagent with the consolidated Critical/Important findings; roll up Minors.
+- [ ] **Step 7.3: Address findings**, re-verify, then use superpowers:finishing-a-development-branch to complete the branch (tests green → present options → execute choice).
+
+---
+
+## Self-Review (author)
+
+- **Spec coverage:** §8 Settings card → Task 4; §9 binaries/GPL note + §11 README → Task 5; §12 "docs, README" → Task 5; §12/§4.3/§13 "recovery/watchdog" (Connect retry/backoff) → Task 6 (device-visibility watchdog + per-track skip already landed in Stage 3); D9 → Task 3; D11 → Task 2; config editability (prereq for the card) → Task 1.
+- **Deferred (documented, NOT built this stage), with rationale:** runtime binary auto-download (spec §9 calls it "optional"; README documents manual install + Docker instead — avoids a tar.gz/checksum/platform-detection downloader on the critical path); the §4.3 `202`-accepted-but-not-effective verification (needs post-command playback-state confirmation the poll-based track-end already tolerates); D10's separate play-not-reflected diagnostic beyond the retry-exhaustion `logger.warn` Task 6 adds. These are listed in the ledger as follow-ups.
+- **Placeholder scan:** backend tasks (1–3) carry complete code; frontend/docs (4–5) carry the tested composable in full + explicit wiring contracts + named existing patterns to mirror (Settings.vue has no component-test harness, so exact `.vue` template text is intentionally pattern-referenced, not dictated line-by-line).
+- **Type consistency:** `SpotifyBackendKind` canonicalized in `backend-select.ts`, re-exported from `controller.ts`; `getBackendInfo` return type updated in both `spotify.ts` and its `server.ts` supplier and the `/status` test; `buildSpotifyPayload`/`SpotifyStatus` shapes match Task 1's masked view (`hasClientSecret`) and Task 2's `/status` (`binaryAvailable`).

docs/superpowers/plans/2026-07-06-jellyfin-source.md

@@ -0,0 +1,53 @@
+# Jellyfin 音源（主音源化）实施计划
+
+目标：自建 Jellyfin 服务器成为默认且主要的音源；现有 NetEase / QQ / Bilibili / YouTube / Kugou
+继续编译但默认停用（`enabledProviders` 配置门控，本次不删除）。约束：`src/audio/*`、
+`src/ts-protocol/*` 不改（唯一例外：`queue.ts` 中 `QueuedSong.platform` 联合类型加一个成员，
+纯类型加宽，无任何逻辑改动，否则无法编译）。
+
+## 触点地图
+
+后端：
+- `src/music/provider.ts` — platform 联合类型加 `"jellyfin"`（Song/Playlist/Album/MusicProvider）
+- `src/audio/queue.ts` — 同上（仅类型，一个词）
+- `src/data/database.ts` — PlayHistoryRecord.platform 加 `"jellyfin"`
+- `src/music/auth.ts` — CookieStore 平台加 `"jellyfin"`（token JSON 与 cookie 同路径持久化）
+- `src/data/config.ts` — 新增 `JellyfinConfig`（serverUrl / authMode / username / password /
+  apiKey / userId）+ `enabledProviders`（默认 `["jellyfin"]`）+ 载入清洗 + `isProviderEnabled` /
+  `defaultPlatform` 助手。spotify 仍由 `spotify.enabled` 门控、local 仍由 `localAudioEnabled` 门控
+- `src/music/jellyfin.ts` — 新 Provider：认证（userpass=AuthenticateByName + MediaBrowser 头，
+  401 重登一次；apikey=X-Emby-Token）、搜索（Audio/MusicAlbum/Playlist, StartIndex 翻页）、
+  懒解析播放 URL（direct=`/Audio/{id}/stream?static=true`；320/192/128=`/Audio/{id}/universal`
+  转码）、歌单/专辑/歌词（ticks→秒，404=无歌词）、收藏→InstantMix 电台链（收藏→最近播放→随机曲目）、
+  最近添加/最多播放/流派、播放上报（Sessions/Playing[/Progress|/Stopped]，全部吞错）、
+  音质档（direct 原始直传 / 320k / 192k / 128k）
+- `src/music/api-server.ts` — 按 provider 开关决定是否绑定 3001/3200
+- `src/index.ts` — 构造 JellyfinProvider、加载持久化 token、穿线
+- `src/bot/manager.ts` — 穿线 jellyfinProvider（与 spotifyProvider 同模式）
+- `src/bot/instance.ts` — jellyfin 分支（getProviderFor / getProvider，新 flag `-j`/`-n`）、
+  默认平台=jellyfin、停用音源友好报错、歌单/专辑命令识别 GUID、播放上报挂钩、帮助文本
+- `src/web/api/music.ts` — provider 选择 + 门控、`/providers`、jellyfin 首页数据端点、音质路由
+- `src/web/api/auth.ts` — jellyfin 状态 + 测试连接（/System/Info）；无 QR
+- `src/web/api/player.ts` — 平台白名单 + platformFlag（netease 显式 `-n`）
+- `src/web/api/bot.ts` — settings 读写 jellyfin 配置块（密码/APIKey 写入不回显）+ 热更新 provider
+
+前端（Vue 3，保持 YesPlayMusic 风格；新增文案 zh+en）：
+- `stores/player.ts` — Source 加 jellyfin、enabledProviders 状态、jellyfin 首页数据
+- `views/Search.vue` — 音源条只显示启用的 provider、Jellyfin 徽标
+- `views/Home.vue` — 最近添加 / 播放最多 / 我的歌单 / 收藏 / 流派 区块 + jellyfin FM 卡片
+- `views/Settings.vue` — Jellyfin 连接卡（地址/认证模式/凭据/测试连接）、隐藏停用 provider 的
+  登录卡、jellyfin 音质档
+- `views/Setup.vue` — 向导第 3 步换成 Jellyfin 连接卡
+- `views/Playlist.vue` 等 — ID 均按 string 处理，审计通过（GUID 无数字假设）
+
+文档：README 增加「Jellyfin 音源」章节 + fork 出处与 MIT 归属（上游
+ZHANGTIANYAO1/teamspeak-music-bot）。
+
+## 阶段与验证
+
+1. 类型 + 配置 → `npx tsc --noEmit`
+2. JellyfinProvider + 单测 → tsc + vitest
+3. 门控 + bot 穿线 → tsc + vitest
+4. REST → tsc + vitest
+5. WebUI → `cd web && npm run build`
+6. README + 全量构建/测试

docs/superpowers/specs/2026-07-01-spotify-source-design.md

@@ -0,0 +1,202 @@
+# Spotify audio source (optional, hybrid librespot) — design spec
+
+- **Issue:** [#112 — Support for Spotify audio source](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/112)
+- **Date:** 2026-07-01
+- **Status:** Approved (design) — pending implementation plan
+- **Chosen approach:** Hybrid — real Spotify streaming via a librespot-family sidecar, with **go-librespot on Linux/Docker** and **Rust librespot on Windows**, behind one backend interface.
+
+---
+
+## 1. Summary
+
+Add `spotify` as a new **optional** `MusicProvider`. Metadata (search / track / album / playlist) is read from the official **Spotify Web API**. Audio is the *real* Spotify stream, produced by a librespot-family sidecar and piped through ffmpeg into the bot's existing voice path.
+
+The feature is **disabled by default**, opt-in, and **requires the user's own Spotify Premium account**. librespot is an unofficial, reverse-engineered client and using it **violates Spotify's Terms of Service** (account-ban risk). This is surfaced to the user as an explicit experimental warning, and no credentials are ever bundled.
+
+If the feature is disabled, unauthenticated, or the sidecar binary is missing, the provider disables itself gracefully — exactly like `YouTubeProvider` when `yt-dlp` is absent (empty results, greyed-out in the UI, no crash).
+
+## 2. Goals / Non-goals
+
+**Goals**
+- First-class `spotify` source: search, play, playlist/album import, lyrics best-effort, login status.
+- Real Spotify audio (Premium), not a YouTube match.
+- Cross-platform: works on the project's three deployments — native Windows one-click, Linux systemd, Docker.
+- Strictly optional and safe-by-default; zero impact when off.
+- Mixed queues keep working (Spotify tracks interleaved with netease/qq/etc.).
+
+**Non-goals**
+- No free-tier audio (Premium is mandatory for librespot streaming).
+- No bundled Spotify credentials or shared Developer app.
+- No replacement of, or change to, existing sources' behavior.
+- No CI e2e against live Spotify (requires Premium; manual only).
+
+## 3. Backend selection
+
+`spotify.backend: "auto" | "go-librespot" | "librespot"` (default `auto`).
+
+| Platform | `auto` resolves to | Why |
+|---|---|---|
+| Windows | `librespot` (Rust) | go-librespot has **no** Windows binary and its FIFO capture is POSIX-only |
+| Linux / Docker | `go-librespot` (fallback `librespot`) | clean REST play-by-URI + prebuilt Linux binary |
+| macOS | `librespot` (or `go-librespot` if built) | no go-librespot macOS binary published |
+
+The split is **platform-determined**, not a per-run user toggle (a user may still force one via config if they have the binary).
+
+## 4. Architecture
+
+### 4.1 The seam — `SpotifyAudioBackend`
+
+New file `src/music/spotify/backend.ts`:
+
+```ts
+export interface SpotifyTrackEndedEvent { uri: string; reason: "ended" | "stopped" | "error"; }
+
+export interface SpotifyAudioBackend {
+  start(): Promise<void>;                    // launch sidecar + resampling ffmpeg
+  stop(): void;                              // tear everything down
+  isReady(): boolean;                        // device online & streamable
+  playTrack(uri: string): Promise<void>;     // begin ONE track (spotify:track:...)
+  pause(): Promise<void>;
+  resume(): Promise<void>;
+  seek(ms: number): Promise<void>;
+  getPcmStream(): Readable;                   // 48kHz s16le stereo (post-ffmpeg)
+  getPosition(): number;                      // ms into current track
+  on(event: "trackEnded", cb: (e: SpotifyTrackEndedEvent) => void): void;
+  on(event: "metadata", cb: (m: SpotifyNowPlaying) => void): void;
+  on(event: "ready" | "error", cb: (arg?: unknown) => void): void;
+}
+```
+
+Both implementations emit the **same** 48 kHz s16le stereo PCM and the **same** events, so everything above the seam (provider, controller, player, UI) is backend-agnostic.
+
+### 4.2 `GoLibrespotBackend` (Linux/Docker) — `src/music/spotify/go-librespot.ts`
+
+- Writes a `config.yml` with `server: { enabled: true, address: 'localhost', port: <p> }`, `audio_backend: 'pipe'`, `audio_output_pipe: '<fifo>'`, `audio_output_pipe_format: 's16le'`, `bitrate: 320`, credentials block.
+- `start()`: `mkfifo <fifo>` → **spawn the FIFO-reading ffmpeg first** → then spawn go-librespot. (FIFO open ordering is mandatory: go-librespot opens the write end with `O_WRONLY|O_NONBLOCK` and errors `ENXIO` if no reader exists yet.) ffmpeg: `-f s16le -ar 44100 -ac 2 -i <fifo> -f s16le -ar 48000 -ac 2 -`. ffmpeg stdout = `getPcmStream()`.
+- Control (REST): `POST /player/play {uri}`, `POST /player/pause`, `POST /player/resume`, `POST /player/seek {position}`. `GET /status` for position.
+- Events (WebSocket `/events`): `metadata` → `metadata`; `not_playing` → `trackEnded` (track boundaries can NOT be read from the FIFO — it is gapless/continuous and never EOFs between tracks).
+- Metadata token: go-librespot exposes `POST /token` (first-party session token) and a `/web-api/<path>` proxy to `api.spotify.com` — so on this backend a separate Spotify Developer app is **optional**.
+- Recovery: on reader death go-librespot's write returns `EPIPE` and closes the pipe output; backend restarts the ffmpeg reader + reactivates the device.
+
+### 4.3 `RustLibrespotBackend` (Windows / cross-platform) — `src/music/spotify/rust-librespot.ts`
+
+Rust librespot is a **passive Spotify Connect receiver**; the bot acts as the **Connect controller** via the Spotify Web API.
+
+- `start()`: spawn `librespot --backend pipe --name "<deviceName>" --bitrate 320 --cache <dir> [--access-token <tok> | --enable-oauth]`. With **no `--device`**, librespot writes raw PCM (**s16le, 44100 Hz, stereo**) to **stdout** (cross-platform; verified against `pipe.rs` — `None => Box::new(io::stdout())`). Pipe stdout → ffmpeg `-f s16le -ar 44100 -ac 2 -i pipe:0 -f s16le -ar 48000 -ac 2 -` → `getPcmStream()`. Do **not** pass `--passthrough` (that emits raw Ogg, not PCM).
+- `playTrack(uri)`: `GET /v1/me/player/devices` → find our `device_id` by `deviceName` → `PUT /v1/me/player/play?device_id={id}` body `{uris:[uri]}`. `pause/resume/seek` → `PUT /v1/me/player/{pause,play,seek}`.
+- `trackEnded`: poll `GET /v1/me/player` (is_playing → false / `item` changed / `progress_ms ≈ duration_ms`) plus optional `--onevent` hook (read-only notifications). Add a watchdog + retry/backoff for device-visibility latency and command `202/404` flakiness.
+- Requires a **user OAuth token** with scopes `streaming user-read-playback-state user-modify-playback-state user-read-currently-playing` (+ `playlist-read-private playlist-read-collaborative` for user playlists).
+
+## 5. Shared subsystems
+
+### 5.1 Metadata — `src/music/spotify/webapi.ts`
+
+Thin `axios` client mapping Spotify catalog objects → the bot's `Song` / `Playlist` / `Album`:
+- `GET /v1/search?type=track,album,playlist&q=…`
+- `GET /v1/tracks/{id}`, `GET /v1/albums/{id}/tracks`, `GET /v1/playlists/{id}/tracks`
+
+All confirmed still available with a normal token **after** Spotify's 2024-11-27 cut (that cut removed related-artists, recommendations, audio-features/analysis, featured/category playlists, and `preview_url` — none of which we use). Token source is pluggable: user Developer-app token (primary) or go-librespot `/web-api` proxy (go-librespot path). Handle `429 Retry-After` (rolling 30 s window; dev-mode quota).
+
+### 5.2 Auth — `src/music/spotify/auth.ts`
+
+One web-UI **Authorization-Code + PKCE** login.
+- **Primary:** the user registers their own Spotify Developer app (Client ID [+ Secret] + redirect URI) — reliable, ToS-cleaner. The resulting access token drives metadata + Web-API control; the refresh token is persisted (credential store); access tokens (~1 h) auto-refresh. The same token bootstraps librespot via `--access-token`, after which librespot caches reusable credentials — **one user-facing login**.
+- **Fallbacks:** librespot `--enable-oauth` (built-in client `65b708073fc0480ea92a077233ca87bd`, redirect `http://127.0.0.1:8898/login`) or go-librespot interactive login (`http://127.0.0.1:36842/login?code=…`) as a separate one-time step; go-librespot `/web-api` proxy when no Developer app is provided.
+- Username/password is **dead** (removed by Spotify in 2024); do not implement it.
+
+### 5.3 Provider — `src/music/spotify/provider.ts`
+
+`SpotifyProvider implements MusicProvider` with `platform: "spotify"`:
+- `search`, `getSongDetail`, `getPlaylistSongs`, `getAlbumSongs`, `getLyrics` (best-effort/empty), `getRecommendPlaylists` → Web API.
+- `getAuthStatus()` reports login state **and** backend/binary availability (drives greying-out in UI, like YouTube).
+- `getSongUrl(id)` returns a **sentinel** (`{ url: "spotify:track:<id>" }`) — actual playback is via the backend/controller, not a URL. `instance.ts` recognizes the sentinel and routes to the `SpotifyController`.
+- QR-code login methods are no-ops; Spotify uses the OAuth card instead.
+
+## 6. Queue / player / instance integration
+
+- **`SpotifyController`** (`src/music/spotify/controller.ts`, one per bot): owns the chosen backend and the Web-API/auth clients; exposes `playTrack/pause/resume/seek/stop` and forwards `trackEnded`/`metadata`.
+- **`AudioPlayer` — new external-PCM mode:** add `playPcmStream(readable, { onExternalEnd })` that feeds the existing `pcmBuffer` → 20 ms frame loop → encoder → `frame` path **without spawning a url-ffmpeg**. For Spotify, `trackEnd` is driven by the backend's `trackEnded` event (the librespot→ffmpeg pipeline is long-lived and does not exit per song). `pause/resume/seek` on a Spotify song are routed to the backend by `instance.ts` (and gate frame emission locally for crisp UI state).
+- **`instance.ts`:** `getProviderFor("spotify")`, a `-s` command flag in `getProvider(flags)`. When a dequeued `song.platform === "spotify"`: ensure the controller/backend is started + device active, `playTrack(uri)`, attach the player to the backend PCM. On `trackEnded` → advance the queue. When a **non-Spotify** song is next, **pause the sidecar** (so it doesn't buffer ahead) and use the normal `player.play(url)` path. This preserves one-track-at-a-time on-demand playback and mixed-source queues.
+- Real-time pacing is guaranteed by the voice consumer: TS voice pulls 20 ms frames at real time → the player reads PCM at real time → ffmpeg's read of the sidecar stalls → sidecar backpressure pauses decode. (This is why go-librespot's pull model avoids the classic librespot "plays too fast / skips" bug; Rust librespot to stdout is likewise paced by our reads.)
+
+## 7. Config, opt-in & safety
+
+`BotConfig.spotify` (all default-off), added to `getDefaultConfig()` and sanitized in `loadConfig()`:
+
+```ts
+spotify: {
+  enabled: false,
+  backend: "auto",              // "auto" | "go-librespot" | "librespot"
+  clientId: "",                 // user's Developer app (optional on go-librespot path)
+  clientSecret: "",             // optional — PKCE needs none; only for confidential/client-credentials flows
+  deviceName: "TSMusicBot",
+  bitrate: 320,                 // 96 | 160 | 320
+}
+```
+
+Inert unless `enabled` **and** logged-in **and** a resolvable binary. First-run/settings shows the experimental + ToS + Premium + own-credentials warning. Never store or transmit shared secrets.
+
+## 8. Web UI
+
+- Add `spotify` to `platform` and `Source` unions (`web/src/stores/player.ts`, `web/src/stores/sourceTabs.ts`).
+- `SourceTabs.vue`: add "Spotify" tab; `SongCard.vue`: green **#1DB954** badge; `variables.scss`: `--brand-spotify` tokens.
+- `stores/player.ts`: extend `authStatus` / `recommendPlaylists` / `dailySongs` / `userPlaylists` maps + the auth/recommend fetch fan-out.
+- Settings: a **Spotify login card distinct from the QR cards** — "Connect Spotify" OAuth button, optional Client ID/Secret fields, backend/binary status indicator, and the risk disclaimer.
+
+## 9. Binary / dependency resolution — `src/music/spotify/binary.ts`
+
+Mirror `findYtDlp()`: resolve `go-librespot` / `librespot(.exe)` from `bin/` then PATH; positive availability cached, negative retried (install-while-running).
+- **No prebuilt Rust librespot exists** (source-only: `cargo install librespot`, distro/`scoop`/`choco`, or a binary dropped in `bin/`).
+- **go-librespot** ships **Linux-only** assets (`go-librespot_linux_{x86_64,arm64,armv6,armv6_rpi}.tar.gz`, ~6 MB, at `github.com/devgianlu/go-librespot/releases`). Docker build downloads the correct Linux asset; optional runtime auto-download (like yt-dlp). go-librespot is **GPL-3.0** → sidecar = mere aggregation (does not infect the Node code); ship its license text + a source offer.
+- Unresolved binary → source disabled with an actionable "install X / see docs" message.
+
+## 10. Testing
+
+Vitest, mocking child processes and HTTP:
+- Web-API response → `Song/Playlist/Album` mapping.
+- `chooseBackend()` per platform/config.
+- Auth: PKCE challenge, token refresh, credential persistence.
+- Config load/sanitize (defaults, hand-edited/corrupt input).
+- `SpotifyProvider` methods (mock webapi).
+- Player external-PCM path: feed a fake `Readable` → assert `frame` emission + `trackEnd` on external end.
+- go-librespot `/events` → `trackEnded` translation; Rust-backend Web-API poll → `trackEnded`.
+- e2e against live Spotify is **manual & documented** (Premium required), not CI.
+
+## 11. Files touched
+
+**New:** `src/music/spotify/{provider,backend,go-librespot,rust-librespot,webapi,auth,controller,binary}.ts` (+ `.test.ts`).
+**Edited (backend):** `src/music/provider.ts` (union: `Song`/`Playlist`/`Album`/`MusicProvider`), `src/index.ts`, `src/bot/manager.ts`, `src/bot/instance.ts` (router + `-s` flag + spotify routing), `src/audio/player.ts` (external-PCM mode), `src/data/config.ts`, `src/music/auth.ts` (credential store union), `src/web/api/auth.ts`, `src/web/api/music.ts` (routers + search aggregation), `src/web/server.ts`, `src/data/database.ts` (platform).
+**Edited (frontend):** `web/src/stores/player.ts`, `web/src/stores/sourceTabs.ts`, `web/src/components/SourceTabs.vue`, `web/src/components/SongCard.vue`, `web/src/styles/variables.scss`.
+**Docs:** `README.md` (Spotify section + warnings + install notes).
+
+## 12. Staged rollout
+
+1. **Metadata + provider + config + UI plumbing** (no audio): `spotify` source searchable/browsable; playback returns "not yet playable". Fully testable without a sidecar.
+2. **go-librespot backend (Linux/Docker):** real playback on Linux; REST + FIFO + WebSocket.
+3. **Rust librespot backend (Windows):** stdout PCM + Web-API Connect control.
+4. **Polish:** recovery/watchdog, docs, binary auto-download, README.
+
+## 13. Risks & open questions
+
+- **Rust librespot control is the top risk** — Connect device visibility/latency, poll-based track-end. Mitigation: retry/backoff + watchdog; degrade to "skipped" on repeated failure.
+- **One-OAuth-token bootstraps librespot** (`--access-token` from the user's own app client) is *plausible but unverified* — may fall back to two one-time logins. Verify with a spike in stage 3.
+- **Windows go-librespot is impossible** (FIFO) → Windows always uses Rust librespot.
+- **Token scope from librespot's built-in client** may not include `user-modify-playback-state`; if so, a user Developer app is required for the Rust/Windows control path.
+- Large surface area → staged rollout above; each stage independently shippable.
+
+## Appendix A — Verified technical facts (with sources)
+
+go-librespot API (`devgianlu/go-librespot`, v0.7.x):
+- REST: `POST /player/{play,pause,resume,playpause,stop,next,prev,seek,volume,add_to_queue}`, `GET /status`, `GET /` (`{playback_ready}`), `POST /token`, `GET|POST /web-api/<path>`. `POST /player/play` body `{uri, skip_to_uri?, paused?}`. Server enabled only when `server.enabled: true`.
+- WebSocket `/events` envelopes `{type, data}`; types include `metadata, will_play, playing, paused, not_playing, stopped, seek, volume, active, inactive`. Track-end = `not_playing`.
+- Pipe backend: continuous raw PCM, no header, 44100 Hz stereo, format `s16le|s32le|f32le`; FIFO opened once; POSIX-only. Backpressure real (blocks when reader stalls).
+- Sources: `github.com/devgianlu/go-librespot` (README, `api-spec.yml`, `daemon/api_server.go`, `output/driver-pipe.go`).
+
+Rust librespot (`librespot-org/librespot`, v0.8.0, MIT):
+- `--backend pipe` with no `--device` → raw PCM to **stdout**; default S16 / 44100 / stereo; `--format` for higher bit depth; `--passthrough` = raw Ogg (do not use). Passive Connect receiver — no play-by-URI; control via Web API Connect. `--onevent` = read-only hook. No prebuilt binaries.
+- Sources: `github.com/librespot-org/librespot` wiki (Audio-Backends, Options), `librespot_playback/audio_backend/pipe.rs`, `docs/authentication.md`.
+
+Spotify auth & Web API:
+- Username/password removed (2024); use OAuth (Auth-Code+PKCE) or Zeroconf. Premium required for librespot audio.
+- Client-Credentials token authorizes `/v1/search` + public track/album/playlist GETs; 2024-11-27 cut did **not** touch these. Token endpoint `POST https://accounts.spotify.com/api/token` (`grant_type=client_credentials`, Basic base64(id:secret), `expires_in=3600`, no refresh). 429 on a rolling 30 s window.
+- Sources: `developer.spotify.com` (Web API docs; 2024-11-27 blog), `librespot` `docs/authentication.md`.

docs/superpowers/specs/2026-07-06-save-load-playlist-design.md

@@ -0,0 +1,227 @@
+# Save/Load Playlists + Queue Persistence — Design
+
+**Issue:** [#119](https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/119) — 加入保存和加载播放清单功能
+**Date:** 2026-07-06
+**Status:** Approved (design), pending implementation plan
+
+## Problem
+
+The play queue lives only in memory (`PlayQueue` inside each `BotInstance`). It is lost in two situations the user calls out:
+
+1. **On restart** — the process stops, the in-memory queue is gone.
+2. **On "直接播放"** — `!play <song>` (and the WebUI "play now" path) call `queue.clear()`, wiping the queue to play one song.
+
+The user wants to stop losing the queue. Two related-but-separate capabilities were agreed:
+
+- **Named save/load** of queues (manual), plus **auto-restore** of the live queue across restarts.
+- An **independent** option to make single-song immediate-play *not* clear the queue.
+
+Everything ships **behind admin/independent toggles that default OFF**, so existing behavior is unchanged until an operator opts in.
+
+## Scope & agreed decisions
+
+| Decision | Choice |
+| --- | --- |
+| Core behavior | **Both** — named save/load **and** auto-restore live queue across restart |
+| Saved-queue ownership | **Per-user** (like `favorite_playlists`), plus a reserved `__shared__` owner for chat + opt-in sharing |
+| Trigger surface | **Web + chat** commands |
+| Auto-restore on restart | **Restore and resume playing** (gated by `savedQueuesEnabled`) |
+| Load semantics | **Replace (default) + append option** (`-a` flag / WebUI Append button) |
+| Feature gate | `savedQueuesEnabled` — **default false, admin-controlled** |
+| Single-play clear | Independent `playKeepsQueue` toggle — **default false** |
+
+### Out of scope (YAGNI)
+
+- Renaming a saved queue (delete + re-save instead).
+- Mid-track resume on restart (resume from the current track's **start**; URLs are re-resolved).
+- Normalized per-song storage (songs stored as a JSON blob).
+- Sharing granularity beyond "private to me" vs "shared" (one boolean).
+
+## Storage approach
+
+A saved queue is an ordered list of songs that is only ever saved and loaded **whole** — never queried song-by-song. So songs are stored as a **JSON `TEXT` blob**, not a normalized child table. Each stored song is a `QueuedSong` **without `url`** (URLs are resolved lazily at play time, exactly as today). This mirrors how `QueuedSong` already flows and keeps the schema to a single row per saved queue.
+
+---
+
+## Feature 1 — Named save/load (`savedQueuesEnabled`)
+
+### Data model
+
+New table:
+
+```sql
+CREATE TABLE IF NOT EXISTS saved_queues (
+  id        INTEGER PRIMARY KEY AUTOINCREMENT,
+  ownerId   TEXT NOT NULL,          -- WebUI user id, or the reserved SHARED owner
+  name      TEXT NOT NULL,
+  songs     TEXT NOT NULL,          -- JSON array of stored songs (QueuedSong minus url)
+  songCount INTEGER NOT NULL DEFAULT 0,
+  createdAt TEXT NOT NULL DEFAULT (datetime('now')),
+  updatedAt TEXT NOT NULL DEFAULT (datetime('now')),
+  UNIQUE(ownerId, name)
+);
+CREATE INDEX IF NOT EXISTS idx_saved_queues_ownerId ON saved_queues(ownerId);
+```
+
+- **`ownerId`** is either a real user id **or** a reserved constant `SHARED_QUEUE_OWNER = "__shared__"` (a value that can never collide with a real user id).
+- **Ownership rule (reconciles per-user with chat):**
+  - **WebUI save** has a **"共享 (shared)" checkbox.** Off → `ownerId = req.user.id` (private to you). On → `ownerId = SHARED_QUEUE_OWNER`.
+  - **Chat `!save`** always writes `ownerId = SHARED_QUEUE_OWNER` (TeamSpeak users have no WebUI account).
+  - **WebUI list** shows **your own + shared** (labeled). **Chat `!queues`/`!load`** see **shared only**.
+- **Overwrite:** `UNIQUE(ownerId, name)` → save is an **upsert** (same owner+name replaces `songs`, `songCount`, `updatedAt`).
+- **Caps** (reject with a clear message): ≤ **50** saved queues per owner; ≤ **1000** songs per saved queue.
+
+### DB methods (added to `BotDatabase`)
+
+```ts
+saveQueue(ownerId: string, name: string, songs: StoredSong[]): SavedQueue;   // upsert
+listSavedQueues(ownerId: string, includeShared: boolean): SavedQueueMeta[];  // meta only (no songs blob)
+getSavedQueue(id: number): SavedQueue | null;                                // full, with songs
+deleteSavedQueue(id: number): boolean;
+```
+
+- `StoredSong` = `Omit<QueuedSong, "url">`.
+- `SavedQueueMeta` = row without the `songs` blob (id, ownerId, name, songCount, timestamps) — keeps list responses light.
+- JSON (de)serialize at the DB boundary; parse failures on a corrupt blob degrade to an empty song list (never throw into a route).
+
+### Web API — `src/web/api/saved-queues.ts`
+
+All routes require auth + `player.queue` capability, and **404/403 when `savedQueuesEnabled` is false** (feature inert).
+
+| Method / path | Behavior |
+| --- | --- |
+| `GET /api/saved-queues` | list current user's own + shared (meta only) |
+| `POST /api/saved-queues` | body `{ botId, name, shared? }` → snapshot that bot's **current queue** songs, upsert |
+| `POST /api/saved-queues/:id/load` | body `{ botId, mode: "replace"\|"append" }` → load into that bot |
+| `DELETE /api/saved-queues/:id` | delete (only own or shared; not another user's private) |
+
+Ownership check on load/delete: allow if `ownerId === req.user.id` or `ownerId === SHARED_QUEUE_OWNER`; else 404 (no existence leak, matching the favorites pattern).
+
+### Chat commands (new, in `BotInstance.executeCommand`)
+
+- `!save <名称>` — save current queue → shared bucket.
+- `!load <名称>` — replace queue with a saved (shared) queue and play.
+- `!load -a <名称>` — append a saved (shared) queue to the end.
+- `!queues` — list shared saved queues (names + counts).
+
+All four reply **"此功能未启用"** when `savedQueuesEnabled` is false. Added to help text and the command table.
+
+### Load semantics (shared by web + chat)
+
+- **replace** — `queue.clear()`, add all stored songs, `queue.play()` + `resolveAndPlay(first)` (same shape as `cmdPlaylist`). Exits FM mode.
+- **append** — add all stored songs to the end; if idle, start the first newly-added one; never interrupts a playing track.
+- Loaded songs are re-tagged with a `requestedBy` of the loader (WebUI username / `游客` / chat `invokerName`) so play-history attribution stays correct (integrates with #121).
+
+### WebUI
+
+A new **"已保存队列 / Saved Queues"** page (nav entry visible only when `savedQueuesEnabled`):
+
+- **Save current queue**: name input + **共享** checkbox → `POST`.
+- Per entry (reusing `SongCard`/list styles): **Load** (replace), **Append**, **Delete**, showing name / song count / shared badge / owner.
+- Store/composable follows the existing `favorites` pattern.
+
+---
+
+## Feature 2 — Auto-restore live queue across restart (`savedQueuesEnabled`)
+
+Gated by the **same** `savedQueuesEnabled` flag (part of the "saved queues" feature).
+
+### Data model
+
+One row per bot (the live snapshot, continuously overwritten):
+
+```sql
+CREATE TABLE IF NOT EXISTS queue_state (
+  botId        TEXT PRIMARY KEY,
+  songs        TEXT NOT NULL,       -- JSON array of StoredSong
+  currentIndex INTEGER NOT NULL,
+  mode         TEXT NOT NULL,       -- PlayMode value
+  isFmMode     INTEGER NOT NULL DEFAULT 0,
+  fmPlatform   TEXT NOT NULL DEFAULT '',
+  updatedAt    TEXT NOT NULL DEFAULT (datetime('now'))
+);
+```
+
+DB methods: `saveQueueState(state)` (upsert), `getQueueState(botId)`, `clearQueueState(botId)`.
+
+### Snapshot (write path)
+
+- Add `PlayQueue.snapshot(): QueueSnapshot` and `PlayQueue.restore(snapshot)`.
+  - `snapshot` captures `songs` (minus url), `currentIndex`, `mode`.
+  - `restore` rebuilds `songs`, `currentIndex`, `mode`, and resets the derived `playedIndices`/`history`/`forwardStack` to a clean, consistent state for the restored index.
+- `BotInstance` writes the snapshot **debounced (~1 s)** on `stateChange` (queue mutations, track changes, and mode changes already emit `stateChange`). FM mode + fm platform captured alongside.
+- When the queue becomes empty (`clear()` with nothing re-added), the row is cleared via `clearQueueState`.
+
+### Restore (read path — "resume and play")
+
+When a bot reaches **connected/ready** (the same lifecycle point `autoStart` uses):
+
+1. If `savedQueuesEnabled` and a `queue_state` row exists → `PlayQueue.restore(...)`, restore FM mode/provider.
+2. If there was a current track → `resolveAndPlay(current)` (re-resolves URL, plays **from the track's start**).
+
+**Honest caveats (documented in README + spec):**
+
+- Resumes the **current track from its start**, not the exact millisecond (URLs are re-resolved; no persisted elapsed/seek).
+- **Spotify** auto-resume is **best-effort** — it depends on the sidecar/controller being back up; non-Spotify sources are reliable.
+- Resume only happens for bots that reach the connected state (auto-started, or on next manual start).
+
+---
+
+## Feature 3 — `playKeepsQueue` (independent single-play toggle)
+
+**Independent** config flag, **not** gated by `savedQueuesEnabled`. Default false → today's behavior.
+
+Affects **single-song immediate play only**: chat `!play <song | #N | id:<id> | URL>` and the WebUI play-now / play-by-id path.
+
+| `playKeepsQueue` | `!play <song>` behavior |
+| --- | --- |
+| `false` (default) | `queue.clear()` → play only that song (today) |
+| `true` | `addNext(song)` (insert after current) → `playAt(insertedAt)` (jump & play now) → `resolveAndPlay`; queue **kept**; on track-end, `next()` continues the queue |
+
+- Reuses existing `PlayQueue.addNext` + `playAt` — **no new queue logic.**
+- **Not** applied to collection loads — `!playlist` / `!album` / `!artist` / `!fm` still replace the queue (loading a collection is meant to replace; the request is about 单曲/single songs).
+- **Empty queue** → equivalent to a normal play (nothing to preserve).
+- **FM mode** → `!play` still exits FM (manual takeover), but existing queued songs are preserved and continue after the single song (auto-refill stops because FM is off). Documented.
+
+---
+
+## Config
+
+Add to `BotConfig` (in `src/data/config.ts`), both **default false**, both sanitized on load exactly like `localAudioEnabled` / `autoPauseOnEmpty` (so a hand-edited / legacy / corrupt `config.json` can never silently enable them):
+
+```ts
+savedQueuesEnabled: boolean;  // default false — gates Features 1 & 2 (admin-controlled)
+playKeepsQueue: boolean;      // default false — independent (Feature 3)
+```
+
+- Set via **Settings → 行为设置** (the existing admin behavior-settings surface, written through `POST /api/bot/settings`).
+- When `savedQueuesEnabled` is false: chat save/load/queues reply "此功能未启用"; `/api/saved-queues/*` return 403/404; the WebUI page/nav is hidden; no snapshotting; no auto-restore.
+
+## Error handling & edge cases
+
+- Corrupt `songs` JSON blob → treated as empty list; never throws into a route or the restore path.
+- Save with a duplicate name → upsert (overwrite), not an error.
+- Load/delete of a non-owned private queue → 404.
+- Caps exceeded → 4xx with a clear message (web) / friendly reply (chat).
+- Snapshot writes are best-effort and debounced; a DB write failure logs and never interrupts playback.
+- Restore of a Spotify-containing queue → best-effort per source; failures skip to next (existing `resolveAndPlay` skip behavior).
+
+## Testing (TDD)
+
+- **DB:** `saveQueue` upsert + caps; `listSavedQueues` own vs shared; `getSavedQueue`/`deleteSavedQueue`; ownership; `queue_state` upsert/get/clear; JSON round-trip + corrupt-blob degradation.
+- **PlayQueue:** `snapshot`/`restore` round-trip (songs, index, mode; derived state consistent).
+- **BotInstance:** `!save`/`!load`/`!load -a`/`!queues`; feature-disabled replies; snapshot-on-stateChange (debounced); resume-on-ready; `playKeepsQueue` insert-and-jump vs clear; collections still replace; FM interaction.
+- **Web API:** auth + capability + feature-gate (403/404); save (own/shared); load replace/append; delete ownership; caps.
+- **Config:** defaults false; load sanitization (legacy/corrupt/non-boolean → false).
+- **Frontend:** Saved Queues page (save w/ shared toggle, load, append, delete, hidden when disabled); store/composable.
+- Then: full suite (`npx vitest run --no-file-parallelism`) + `npx tsc --noEmit` + `cd web && npm run build`.
+
+## Rollout / staging
+
+Implement in stages (each independently valuable, all default-off):
+
+1. **Config + gates** — `savedQueuesEnabled`, `playKeepsQueue`, sanitization, Settings UI.
+2. **Feature 3** — `playKeepsQueue` single-play behavior (small, self-contained).
+3. **Feature 1** — named save/load (DB → API → chat → WebUI page).
+4. **Feature 2** — live-queue snapshot + resume-on-restart.
+5. **Docs** — README (commands, toggles, caveats).

package.json

@@ -3,10 +3,15 @@
   "version": "0.1.0",
   "description": "TeamSpeak music bot with NetEase Cloud Music and QQ Music support",
   "type": "module",
+  "engines": {
+    "node": "^22.12.0 || >=24.0.0"
+  },
   "scripts": {
     "dev": "tsx watch src/index.ts",
     "build": "tsc && npm run build:web",
     "build:web": "cd web && npm run build",
+    "check:native": "node scripts/check-native.mjs",
+    "prestart": "node scripts/check-native.mjs",
     "start": "node dist/index.js",
     "play": "node dist/index.js",
     "test": "vitest run",
@@ -17,7 +22,7 @@
     "@discordjs/opus": "^0.10.0",
     "@honeybbq/teamspeak-client": "^0.2.1",
     "@koa/router": "^15.4.0",
-    "@sansenjian/qq-music-api": "^2.2.10",
+    "@sansenjian/qq-music-api": "~2.4.0",
     "axios": "^1.14.0",
     "bcryptjs": "^2.4.3",
     "better-sqlite3": "^12.8.0",
@@ -28,7 +33,7 @@
     "koa": "^3.2.0",
     "koa-bodyparser": "^4.4.1",
     "koa-static": "^5.0.0",
-    "NeteaseCloudMusicApi": "^4.30.0",
+    "NeteaseCloudMusicApi": "~4.32.0",
     "pino": "^10.3.1",
     "ts3-nodejs-library": "^3.5.1",
     "tweetnacl": "^1.0.3",
@@ -47,5 +52,13 @@
     "tsx": "^4.21.0",
     "typescript": "^6.0.2",
     "vitest": "^4.1.2"
+  },
+  "allowScripts": {
+    "@discordjs/opus@0.10.0": true,
+    "better-sqlite3@12.11.1": true,
+    "cpu-features@0.0.10": true,
+    "esbuild@0.28.1": true,
+    "ffmpeg-static@5.3.0": true,
+    "ssh2@1.17.0": true
   }
 }

pr57.diff

@@ -0,0 +1,591 @@
+diff --git a/src/music/netease.test.ts b/src/music/netease.test.ts
+index b2adb3d..ecc2202 100644
+--- a/src/music/netease.test.ts
++++ b/src/music/netease.test.ts
+@@ -1,5 +1,5 @@
+ import { describe, it, expect } from "vitest";
+-import { parseLyrics } from "./netease.js";
++import { parseLyrics, mapNeteaseAlbums } from "./netease.js";
+ 
+ describe("NetEase adapter", () => {
+   it("parses LRC format lyrics", () => {
+@@ -28,4 +28,32 @@ describe("NetEase adapter", () => {
+     expect(lines[0].text).toBe("Hello world");
+     expect(lines[0].translation).toBe("你好世界");
+   });
++
++  it("mapNeteaseAlbums maps raw cloudsearch albums to Album shape", () => {
++    const raw = [
++      {
++        id: 42,
++        name: "Album A",
++        picUrl: "https://x/p.jpg",
++        artists: [{ name: "Artist X" }, { name: "Featured Y" }],
++        size: 12,
++      },
++      {
++        id: 99,
++        name: "Album B",
++        picUrl: "",
++        artists: [],
++      },
++    ];
++    expect(mapNeteaseAlbums(raw)).toEqual([
++      { id: "42", name: "Album A", artist: "Artist X / Featured Y", coverUrl: "https://x/p.jpg", songCount: 12, platform: "netease" },
++      { id: "99", name: "Album B", artist: "", coverUrl: "", songCount: 0, platform: "netease" },
++    ]);
++  });
++
++  it("mapNeteaseAlbums returns [] for empty/null input", () => {
++    expect(mapNeteaseAlbums([])).toEqual([]);
++    expect(mapNeteaseAlbums(null as any)).toEqual([]);
++    expect(mapNeteaseAlbums(undefined as any)).toEqual([]);
++  });
+ });
+diff --git a/src/music/netease.ts b/src/music/netease.ts
+index 8aaeab6..4a863db 100644
+--- a/src/music/netease.ts
++++ b/src/music/netease.ts
+@@ -8,6 +8,7 @@ import type {
+   SearchResult,
+   QrCodeResult,
+   AuthStatus,
++  Album,
+ } from "./provider.js";
+ 
+ export function parseLyrics(lrc: string, tlyric?: string): LyricLine[] {
+@@ -55,6 +56,18 @@ export function parseLyrics(lrc: string, tlyric?: string): LyricLine[] {
+   return lines.sort((a, b) => a.time - b.time);
+ }
+ 
++export function mapNeteaseAlbums(raw: any[] | null | undefined): Album[] {
++  if (!Array.isArray(raw)) return [];
++  return raw.map((a) => ({
++    id: String(a.id),
++    name: a.name ?? "",
++    artist: (a.artists ?? []).map((x: any) => x.name).join(" / "),
++    coverUrl: a.picUrl ?? "",
++    songCount: a.size ?? 0,
++    platform: "netease",
++  }));
++}
++
+ // NetEase quality levels: standard(128k) higher(192k) exhigh(320k) lossless(flac) hires(hi-res) jyeffect jymaster
+ export const NETEASE_QUALITY_LEVELS = [
+   { value: "standard", label: "标准 (128kbps)", bitrate: 128 },
+@@ -91,7 +104,7 @@ export class NeteaseProvider implements MusicProvider {
+   }
+ 
+   async search(query: string, limit = 20): Promise<SearchResult> {
+-    const [songRes, playlistRes] = await Promise.all([
++    const [songRes, playlistRes, albumRes] = await Promise.all([
+       this.api.get("/cloudsearch", {
+         params: { keywords: query, type: 1, limit, ...this.cookieParams },
+       }),
+@@ -103,6 +116,9 @@ export class NeteaseProvider implements MusicProvider {
+           ...this.cookieParams,
+         },
+       }),
++      this.api.get("/cloudsearch", {
++        params: { keywords: query, type: 10, limit: 5, ...this.cookieParams },
++      }),
+     ]);
+ 
+     const songs: Song[] = (songRes.data?.result?.songs ?? []).map(
+@@ -127,7 +143,9 @@ export class NeteaseProvider implements MusicProvider {
+       platform: "netease",
+     }));
+ 
+-    return { songs, playlists, albums: [] };
++    const albums = mapNeteaseAlbums(albumRes.data?.result?.albums);
++
++    return { songs, playlists, albums };
+   }
+ 
+   async getSongUrl(songId: string, quality?: string): Promise<string | null> {
+diff --git a/src/music/qq.test.ts b/src/music/qq.test.ts
+new file mode 100644
+index 0000000..4f606cf
+--- /dev/null
++++ b/src/music/qq.test.ts
+@@ -0,0 +1,43 @@
++import { describe, it, expect } from "vitest";
++import { mapQqAlbums } from "./qq.js";
++
++describe("QQ adapter", () => {
++  it("mapQqAlbums maps albumMID-style raw entries", () => {
++    const raw = [
++      {
++        albumMID: "abc",
++        albumName: "Aero",
++        singerName: "Singer A",
++      },
++      {
++        albumMID: "xyz",
++        albumName: "Beta",
++        singer: [{ name: "Singer B" }, { name: "Singer C" }],
++      },
++    ];
++    const out = mapQqAlbums(raw);
++    expect(out).toHaveLength(2);
++    expect(out[0]).toMatchObject({
++      id: "abc",
++      name: "Aero",
++      artist: "Singer A",
++      platform: "qq",
++    });
++    expect(out[0].coverUrl).toContain("T002R300x300M000abc.jpg");
++    expect(out[1].artist).toBe("Singer B / Singer C");
++    expect(out[1].coverUrl).toContain("xyz");
++  });
++
++  it("mapQqAlbums returns [] for empty/null input", () => {
++    expect(mapQqAlbums([])).toEqual([]);
++    expect(mapQqAlbums(null as any)).toEqual([]);
++    expect(mapQqAlbums(undefined as any)).toEqual([]);
++  });
++
++  it("mapQqAlbums falls back to albumPic when no albumMID", () => {
++    const raw = [{ albumName: "C", albumPic: "https://x/p.jpg", singerName: "S" }];
++    const out = mapQqAlbums(raw);
++    expect(out[0].coverUrl).toBe("https://x/p.jpg");
++    expect(out[0].id).toBe("");
++  });
++});
+diff --git a/src/music/qq.ts b/src/music/qq.ts
+index 9c0360d..1e7a8ae 100644
+--- a/src/music/qq.ts
++++ b/src/music/qq.ts
+@@ -8,6 +8,7 @@ import type {
+   SearchResult,
+   QrCodeResult,
+   AuthStatus,
++  Album,
+ } from "./provider.js";
+ import { parseLyrics } from "./netease.js";
+ 
+@@ -27,6 +28,26 @@ const qqFavApi = axios.create({
+   headers: { referer: "https://y.qq.com/" },
+ });
+ 
++export function mapQqAlbums(raw: any[] | null | undefined): Album[] {
++  if (!Array.isArray(raw)) return [];
++  return raw.map((a) => {
++    const id = String(a.albumMID ?? a.mid ?? a.albumID ?? "");
++    const artist = a.singerName
++      ?? (Array.isArray(a.singer) ? a.singer.map((s: any) => s.name).join(" / ") : "");
++    const coverUrl = id
++      ? `https://y.gtimg.cn/music/photo_new/T002R300x300M000${id}.jpg`
++      : (a.albumPic ?? "");
++    return {
++      id,
++      name: a.albumName ?? a.title ?? "",
++      artist,
++      coverUrl,
++      songCount: a.song_count ?? a.songCount ?? 0,
++      platform: "qq" as const,
++    };
++  });
++}
++
+ function computeGtk(pSkey: string): number {
+   let hash = 5381;
+   for (let i = 0; i < pSkey.length; i++) {
+@@ -65,11 +86,12 @@ export class QQMusicProvider implements MusicProvider {
+       req_0: {
+         module: "music.search.SearchCgiService",
+         method: "DoSearchForQQMusicDesktop",
+-        param: {
+-          searchid: "1",
+-          query,
+-          num_per_page: Math.min(limit, 50),
+-        },
++        param: { searchid: "1", query, num_per_page: Math.min(limit, 50), search_type: 0 },
++      },
++      req_album: {
++        module: "music.search.SearchCgiService",
++        method: "DoSearchForQQMusicDesktop",
++        param: { searchid: "1", query, num_per_page: 5, search_type: 8 },
+       },
+     });
+     const res = await qqDirectApi.get("/cgi-bin/musicu.fcg", {
+@@ -90,7 +112,10 @@ export class QQMusicProvider implements MusicProvider {
+       platform: "qq",
+     }));
+ 
+-    return { songs, playlists: [], albums: [] };
++    const albumList: any[] = res.data?.req_album?.data?.body?.album?.list ?? [];
++    const albums = mapQqAlbums(albumList);
++
++    return { songs, playlists: [], albums };
+   }
+ 
+   async getSongUrl(songId: string, quality?: string): Promise<string | null> {
+diff --git a/src/web/api/music.ts b/src/web/api/music.ts
+index b08f9a2..edf9c04 100644
+--- a/src/web/api/music.ts
++++ b/src/web/api/music.ts
+@@ -52,14 +52,20 @@ export function createMusicRouter(
+       ]);
+ 
+       const songs = [
+-        ...(neteaseResult.status === "fulfilled"
+-          ? neteaseResult.value.songs
+-          : []),
++        ...(neteaseResult.status === "fulfilled" ? neteaseResult.value.songs : []),
+         ...(qqResult.status === "fulfilled" ? qqResult.value.songs : []),
+         ...(bilibiliResult.status === "fulfilled" ? bilibiliResult.value.songs : []),
+       ];
++      const albums = [
++        ...(neteaseResult.status === "fulfilled" ? neteaseResult.value.albums : []),
++        ...(qqResult.status === "fulfilled" ? qqResult.value.albums : []),
++      ];
++      const playlists = [
++        ...(neteaseResult.status === "fulfilled" ? neteaseResult.value.playlists : []),
++        ...(qqResult.status === "fulfilled" ? qqResult.value.playlists : []),
++      ];
+ 
+-      res.json({ songs });
++      res.json({ songs, albums, playlists });
+     } catch (err) {
+       logger.error({ err }, "Unified search failed");
+       res.status(500).json({ error: (err as Error).message });
+diff --git a/src/web/api/player.ts b/src/web/api/player.ts
+index a9af600..4f0930b 100644
+--- a/src/web/api/player.ts
++++ b/src/web/api/player.ts
+@@ -313,6 +313,78 @@ export function createPlayerRouter(
+     }
+   });
+ 
++  // Play an album by ID — mirrors play-playlist but calls getAlbumSongs
++  router.post("/:botId/play-album", async (req, res) => {
++    try {
++      const bot = (req as any).bot;
++      const { albumId, platform } = req.body;
++      const provider = bot.getProviderFor(
++        platform === "bilibili" || platform === "qq" || platform === "youtube"
++          ? platform
++          : "netease"
++      );
++
++      // Stop current playback
++      bot.getPlayer().stop();
++      bot.getPlayer().resetFailures();
++
++      const songs = await provider.getAlbumSongs(albumId);
++      if (songs.length === 0) {
++        res.json({ message: "Album is empty" });
++        return;
++      }
++
++      // QQ-specific optimization: batch-resolve playable IDs to avoid
++      // wasting retries on region/copyright-restricted tracks.
++      let queueable: { id: string }[] = songs;
++      const totalCount = songs.length;
++      const qqLike = provider as { getPlayableSongIds?: (ids: string[]) => Promise<Set<string> | null> };
++      if (typeof qqLike.getPlayableSongIds === "function") {
++        const playable = await qqLike.getPlayableSongIds(songs.map((s: { id: string }) => s.id));
++        if (playable !== null) {
++          queueable = songs.filter((s: { id: string }) => playable.has(s.id));
++        }
++      }
++      if (queueable.length === 0) {
++        res.json({ ok: false, message: `专辑 ${totalCount} 首歌曲均无版权可播放（区域/版权限制）` });
++        return;
++      }
++
++      const queue = bot.getQueueManager();
++      queue.clear();
++      for (const song of queueable) {
++        queue.add({ ...song, platform: provider.platform });
++      }
++
++      const mode = queue.getMode();
++      let first;
++      if (mode === "random" || mode === "rloop") {
++        const idx = Math.floor(Math.random() * queue.size());
++        first = queue.playAt(idx);
++      } else {
++        first = queue.play();
++      }
++
++      let started = first ? await bot.resolveAndPlay(first) : false;
++      if (first && !started) {
++        started = await bot.playNext(20);
++      }
++
++      const playing = queue.current();
++      const loadedMsg = queueable.length < totalCount
++        ? `已加载 ${queueable.length}/${totalCount} 首（其余区域/版权限制）`
++        : `已加载 ${queueable.length} 首`;
++      if (started && playing) {
++        res.json({ ok: true, message: `${loadedMsg}，正在播放：${playing.name}` });
++      } else {
++        res.json({ ok: false, message: `${loadedMsg}，但无法开始播放。` });
++      }
++    } catch (err) {
++      logger.error({ err }, "play-album failed");
++      res.status(500).json({ error: (err as Error).message });
++    }
++  });
++
+   // Play a single song by ID — resolves URL on demand
+   router.post("/:botId/play-song", async (req, res) => {
+     try {
+diff --git a/web/src/router/index.ts b/web/src/router/index.ts
+index cc060f5..d62afcd 100644
+--- a/web/src/router/index.ts
++++ b/web/src/router/index.ts
+@@ -22,6 +22,13 @@ const router = createRouter({
+       path: '/playlist/:id',
+       name: 'playlist',
+       component: () => import('../views/Playlist.vue'),
++      meta: { kind: 'playlist' },
++    },
++    {
++      path: '/album/:id',
++      name: 'album',
++      component: () => import('../views/Playlist.vue'),
++      meta: { kind: 'album' },
+     },
+     {
+       path: '/lyrics',
+diff --git a/web/src/stores/player.ts b/web/src/stores/player.ts
+index 9bc817d..083262c 100644
+--- a/web/src/stores/player.ts
++++ b/web/src/stores/player.ts
+@@ -322,6 +322,16 @@ export const usePlayerStore = defineStore('player', {
+       this._syncAfterAction();
+     },
+ 
++    async playAlbum(albumId: string, platform = 'netease') {
++      if (!this.activeBotId) return;
++      const res = await axios.post(`/api/player/${this.activeBotId}/play-album`, { albumId, platform });
++      if (res.data?.message) {
++        this.notify(res.data.message, res.data.ok === false ? 'error' : 'info');
++      }
++      this._setTiming(this.activeBotId, { serverElapsed: 0 });
++      this._syncAfterAction();
++    },
++
+     async pause() {
+       if (!this.activeBotId) return;
+       // Freeze elapsed at current interpolated value
+diff --git a/web/src/views/Playlist.vue b/web/src/views/Playlist.vue
+index d5c9f8d..d00101d 100644
+--- a/web/src/views/Playlist.vue
++++ b/web/src/views/Playlist.vue
+@@ -38,7 +38,7 @@
+       </div>
+     </template>
+ 
+-    <div v-else class="loading">歌单不存在或加载失败</div>
++    <div v-else class="loading">{{ kind === 'album' ? '专辑' : '歌单' }}不存在或加载失败</div>
+   </div>
+ </template>
+ 
+@@ -64,6 +64,8 @@ interface PlaylistDetail {
+   songCount: number;
+ }
+ 
++const kind = (route.meta.kind as string) ?? 'playlist'; // 'playlist' | 'album'
++
+ const playlist = ref<PlaylistDetail | null>(null);
+ const songs = ref<Song[]>([]);
+ const loading = ref(true);
+@@ -71,20 +73,32 @@ const loading = ref(true);
+ async function playAll() {
+   const id = route.params.id as string;
+   const platform = (route.query.platform as string) || 'netease';
+-  await store.playPlaylist(id, platform);
++  if (kind === 'album') {
++    await store.playAlbum(id, platform);
++  } else {
++    await store.playPlaylist(id, platform);
++  }
+ }
+ 
+ onMounted(async () => {
+   const id = route.params.id as string;
+   const platform = (route.query.platform as string) || 'netease';
+ 
++  const detailUrl = kind === 'album'
++    ? `/api/music/album/${id}/detail`
++    : `/api/music/playlist/${id}/detail`;
++  const songsUrl = kind === 'album'
++    ? `/api/music/album/${id}`
++    : `/api/music/playlist/${id}`;
++
+   // allSettled, not Promise.all — if detail 404s but songs is fine
+   // (e.g., a QQ playlist whose detail endpoint flaked but the song
+   // list resolved), we still want to show the songs rather than
+-  // the "歌单不存在" empty state.
++  // the "不存在" empty state. For albums, detail always 404s — that
++  // is intentional; the fallback stub below handles it.
+   const [detailRes, songsRes] = await Promise.allSettled([
+-    axios.get(`/api/music/playlist/${id}/detail`, { params: { platform } }),
+-    axios.get(`/api/music/playlist/${id}`, { params: { platform } }),
++    axios.get(detailUrl, { params: { platform } }),
++    axios.get(songsUrl, { params: { platform } }),
+   ]);
+ 
+   const detail = detailRes.status === 'fulfilled' ? detailRes.value.data?.playlist : null;
+@@ -96,7 +110,7 @@ onMounted(async () => {
+     // Fall back to a stub built from the route + first song's cover.
+     playlist.value = {
+       id,
+-      name: '歌单',
++      name: kind === 'album' ? '专辑' : '歌单',
+       description: '',
+       coverUrl: songList[0]?.coverUrl ?? '',
+       songCount: songList.length,
+@@ -104,7 +118,7 @@ onMounted(async () => {
+   } else {
+     playlist.value = null;
+     if (detailRes.status === 'rejected') {
+-      console.error('Failed to load playlist detail:', (detailRes.reason as any)?.response?.status, (detailRes.reason as any)?.message);
++      console.error('Failed to load detail:', (detailRes.reason as any)?.response?.status, (detailRes.reason as any)?.message);
+     }
+   }
+   songs.value = songList;
+diff --git a/web/src/views/Search.vue b/web/src/views/Search.vue
+index 0536e36..8822277 100644
+--- a/web/src/views/Search.vue
++++ b/web/src/views/Search.vue
+@@ -20,22 +20,54 @@
+ 
+     <div v-if="loading" class="loading">搜索中...</div>
+ 
+-    <div v-else-if="results.length > 0" class="results">
+-      <SongCard
+-        v-for="(song, i) in results"
+-        :key="`${song.platform}-${song.id}`"
+-        :song="song"
+-        :index="i + 1"
+-        :active="store.currentSong?.id === song.id"
+-        @play="store.playSong(song)"
+-        @playNext="store.playNextSong(song)"
+-        @add="store.addSong(song)"
+-      />
+-    </div>
++    <template v-else-if="songs.length || albums.length || playlists.length">
++      <section v-if="albums.length" class="result-section">
++        <h2 class="section-title">专辑</h2>
++        <div class="card-grid">
++          <router-link
++            v-for="al in albums"
++            :key="`${al.platform}-${al.id}`"
++            :to="`/album/${al.id}?platform=${al.platform}`"
++            class="card hover-scale"
++          >
++            <CoverArt :url="al.coverUrl" :size="160" :radius="10" :show-shadow="true" />
++            <div class="card-name">{{ al.name }}</div>
++            <div class="card-sub">{{ al.artist }}</div>
++          </router-link>
++        </div>
++      </section>
++
++      <section v-if="playlists.length" class="result-section">
++        <h2 class="section-title">歌单</h2>
++        <div class="card-grid">
++          <router-link
++            v-for="pl in playlists"
++            :key="`${pl.platform}-${pl.id}`"
++            :to="`/playlist/${pl.id}?platform=${pl.platform}`"
++            class="card hover-scale"
++          >
++            <CoverArt :url="pl.coverUrl" :size="160" :radius="10" :show-shadow="true" />
++            <div class="card-name">{{ pl.name }}</div>
++          </router-link>
++        </div>
++      </section>
++
++      <section v-if="songs.length" class="result-section">
++        <h2 class="section-title">单曲</h2>
++        <SongCard
++          v-for="(song, i) in songs"
++          :key="`${song.platform}-${song.id}`"
++          :song="song"
++          :index="i + 1"
++          :active="store.currentSong?.id === song.id"
++          @play="store.playSong(song)"
++          @playNext="store.playNextSong(song)"
++          @add="store.addSong(song)"
++        />
++      </section>
++    </template>
+ 
+-    <div v-else-if="searched" class="empty">
+-      未找到相关结果
+-    </div>
++    <div v-else-if="searched" class="empty">未找到相关结果</div>
+   </div>
+ </template>
+ 
+@@ -45,15 +77,21 @@ import { useRoute } from 'vue-router';
+ import { Icon } from '@iconify/vue';
+ import axios from 'axios';
+ import { usePlayerStore } from '../stores/player.js';
++import type { Song } from '../stores/player.js';
+ import SongCard from '../components/SongCard.vue';
++import CoverArt from '../components/CoverArt.vue';
+ 
+ const store = usePlayerStore();
+ const route = useRoute();
+ 
+ const query = ref((route.query.q as string) || '');
+-import { Song } from '../stores/player.js';
+ 
+-const results = ref<Song[]>([]);
++interface Album { id: string; name: string; artist: string; coverUrl: string; songCount?: number; platform: string; }
++interface Playlist { id: string; name: string; coverUrl: string; songCount?: number; platform: string; }
++
++const songs = ref<Song[]>([]);
++const albums = ref<Album[]>([]);
++const playlists = ref<Playlist[]>([]);
+ const loading = ref(false);
+ const searched = ref(false);
+ 
+@@ -62,12 +100,12 @@ async function doSearch() {
+   loading.value = true;
+   searched.value = true;
+   try {
+-    const res = await axios.get('/api/music/search/all', {
+-      params: { q: query.value },
+-    });
+-    results.value = res.data.songs;
++    const res = await axios.get('/api/music/search/all', { params: { q: query.value } });
++    songs.value = res.data.songs ?? [];
++    albums.value = res.data.albums ?? [];
++    playlists.value = res.data.playlists ?? [];
+   } catch {
+-    results.value = [];
++    songs.value = []; albums.value = []; playlists.value = [];
+   } finally {
+     loading.value = false;
+   }
+@@ -141,4 +179,23 @@ onMounted(() => {
+   flex-direction: column;
+   gap: 2px;
+ }
++
++.result-section {
++  margin-bottom: 32px;
++  .section-title { font-size: 18px; margin: 0 0 12px; opacity: 0.85; }
++}
++.card-grid {
++  display: grid;
++  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
++  gap: 16px;
++}
++.card {
++  display: flex;
++  flex-direction: column;
++  gap: 6px;
++  text-decoration: none;
++  color: inherit;
++  .card-name { font-size: 14px; line-height: 1.3; max-height: 2.6em; overflow: hidden; }
++  .card-sub  { font-size: 12px; opacity: 0.6; }
++}
+ </style>

scripts/check-native.mjs

@@ -0,0 +1,155 @@
+#!/usr/bin/env node
+
+/**
+ * Preflight: can THIS Node build actually load the native modules that are
+ * sitting in node_modules?
+ *
+ * A compiled addon is tied to one Node ABI (process.versions.modules:
+ * Node 20 = 115, Node 22 = 127, Node 24 = 137). Install under one Node major,
+ * launch under another, and the bot dies deep inside startup with a
+ * `NODE_MODULE_VERSION ...` stack that says nothing about how to fix it.
+ * This script turns that into one actionable sentence, before anything starts.
+ *
+ * Exit code:
+ *   0  every required native module loads (or is simply not installed yet —
+ *      that is npm install's problem, not an ABI problem)
+ *   1  a required native module definitively fails to load; the bot could not
+ *      have started anyway, so there is no false-positive risk here.
+ *
+ * Usage: node scripts/check-native.mjs
+ */
+
+import { execFileSync } from "node:child_process";
+import { existsSync, readFileSync } from "node:fs";
+import { dirname, join } from "node:path";
+import { fileURLToPath } from "node:url";
+import { createLineWriter } from "./lib/console-log.mjs";
+
+const ROOT = join(dirname(fileURLToPath(import.meta.url)), "..");
+const NODE_MODULES = join(ROOT, "node_modules");
+const STAMP_FILE = join(NODE_MODULES, ".tsmusicbot-abi");
+const NODE_ABI = process.versions.modules;
+
+/** Only the modules the bot cannot start without. ffmpeg-static is optional
+ *  (a system ffmpeg on PATH works too), so it is not checked here. */
+const REQUIRED = ["@discordjs/opus", "better-sqlite3"];
+
+function pkgDirOf(spec) {
+  return join(NODE_MODULES, ...spec.split("/"));
+}
+
+function summarizeError(text) {
+  const lines = String(text || "")
+    .split(/\r?\n/)
+    .map((l) => l.trim())
+    .filter(Boolean);
+  const interesting = lines.find((l) => /NODE_MODULE_VERSION|Error:|error:/.test(l));
+  return (interesting || lines[0] || "unknown error").slice(0, 300);
+}
+
+/**
+ * The snippet that actually forces each package's addon to be dlopen()ed.
+ * NOTE: better-sqlite3 loads its .node lazily, inside the Database constructor,
+ * so a bare `require('better-sqlite3')` succeeds even against a wrong-ABI
+ * binary. Opening an in-memory database is the cheapest way to really load it.
+ */
+const PROBE_EXPR = {
+  "@discordjs/opus": "require('@discordjs/opus')",
+  "better-sqlite3": "new (require('better-sqlite3'))(':memory:').close()",
+};
+
+/**
+ * Load-probe in a throwaway child process. Child process on purpose: requiring
+ * an addon in this process would keep the DLL mapped, and Windows then refuses
+ * to let setup.bat replace the file we just told the user to replace.
+ */
+function probeRequire(spec) {
+  const expr = PROBE_EXPR[spec] || `require(${JSON.stringify(spec)})`;
+  try {
+    execFileSync(process.execPath, ["-e", expr], {
+      cwd: ROOT,
+      stdio: "pipe",
+      timeout: 120000,
+      windowsHide: true,
+    });
+    return { ok: true };
+  } catch (err) {
+    const text = [err.stderr && err.stderr.toString(), err.message].filter(Boolean).join("\n");
+    // "...compiled against ... NODE_MODULE_VERSION 137. This version of Node.js
+    //  requires NODE_MODULE_VERSION 127..." -> first number is the build target.
+    const abis = [...text.matchAll(/NODE_MODULE_VERSION (\d+)/g)].map((m) => m[1]);
+    return {
+      ok: false,
+      abiMismatch: abis.length >= 2,
+      compiledAbi: abis.length >= 2 ? abis[0] : null,
+      error: summarizeError(text),
+    };
+  }
+}
+
+function readStamp() {
+  try {
+    return JSON.parse(readFileSync(STAMP_FILE, "utf8"));
+  } catch {
+    return null;
+  }
+}
+
+const setupCmd = process.platform === "win32" ? "scripts\\setup.bat" : "bash scripts/setup.sh";
+
+const broken = [];
+for (const spec of REQUIRED) {
+  if (!existsSync(pkgDirOf(spec))) continue; // not installed yet -> npm install's job
+  const probe = probeRequire(spec);
+  if (!probe.ok) broken.push({ spec, ...probe });
+}
+
+function report() {
+  const stamp = readStamp();
+  const mismatch = broken.find((b) => b.abiMismatch);
+  // Never let a failed console write become an uncaught error and replace this
+  // report with a stack trace - the console that cannot print the Chinese half
+  // of these lines is exactly the one a user needs the English half from.
+  // See scripts/lib/console-log.mjs and issue #152.
+  const out = createLineWriter(process.stderr);
+
+  out("");
+  out("============================================================");
+  if (mismatch) {
+    out("  [ERROR] 原生模块与当前 Node 版本不匹配");
+    out("          Native modules do not match this Node version");
+  } else {
+    out("  [ERROR] 原生模块无法加载 / native module failed to load");
+  }
+  out("============================================================");
+  out(`  本机 Node / running Node : ${process.version}  (ABI ${NODE_ABI})`);
+  if (stamp && stamp.abi) {
+    out(`  安装时 Node / built with : ${stamp.nodeVersion || "?"}  (ABI ${stamp.abi})`);
+    out(`                             ← node_modules/.tsmusicbot-abi, ${stamp.updatedAt || "?"}`);
+  }
+  out("");
+  for (const b of broken) {
+    if (b.abiMismatch) {
+      out(`  x ${b.spec}: 本机 Node ${process.version} (ABI ${NODE_ABI}),`);
+      out(`      但 node_modules 里的原生模块是给 ABI ${b.compiledAbi} 编译的。`);
+      out(`      built for ABI ${b.compiledAbi}, this Node needs ABI ${NODE_ABI}.`);
+    } else {
+      out(`  x ${b.spec}: ${b.error}`);
+    }
+  }
+  out("");
+  out("  怎么修 / How to fix:");
+  out(`    1) 重新运行安装脚本 / re-run setup:  ${setupCmd}`);
+  out("       (它会自动为当前 Node 版本重新安装原生模块)");
+  out("       (setup now repairs the native modules for whatever Node you run)");
+  out("    2) 或者换回安装时用的 Node 版本 / or switch back to the Node version");
+  out("       you installed with, then start again.");
+  out("============================================================");
+  out("");
+}
+
+if (broken.length > 0) {
+  report();
+  // exitCode rather than exit(): lets the message flush when stderr is piped.
+  process.exitCode = 1;
+}

scripts/docker/Dockerfile

@@ -4,7 +4,7 @@
 # ==========================================
 
 # --- Stage 1: Build backend + frontend ---
-FROM node:20-slim AS builder
+FROM node:22-slim AS builder
 
 # Install build tools for native modules (opus, better-sqlite3)
 RUN apt-get update && apt-get install -y --no-install-recommends \
@@ -30,7 +30,7 @@ RUN npm run build
 RUN rm -rf node_modules && npm ci --production && npm cache clean --force
 
 # --- Stage 2: Production image ---
-FROM node:20-slim
+FROM node:22-slim
 
 # Install system FFmpeg — the ffmpeg-static npm package bundles a pre-compiled
 # binary that can SIGSEGV inside Docker (incompatible glibc / missing libs).
@@ -46,6 +46,13 @@ COPY --from=builder /app/dist ./dist
 COPY --from=builder /app/web/dist ./web/dist
 COPY --from=builder /app/package*.json ./
 COPY --from=builder /app/node_modules ./node_modules
+# package.json declares a `prestart` preflight, so `npm start` inside the
+# container needs this file. The image's own CMD calls node directly and never
+# goes through npm, but an interactive `docker exec ... npm start` would
+# otherwise die on a missing script rather than starting the bot.
+COPY --from=builder /app/scripts/check-native.mjs ./scripts/check-native.mjs
+# ...and the module it imports for crash-proof logging.
+COPY --from=builder /app/scripts/lib/console-log.mjs ./scripts/lib/console-log.mjs
 
 # Data directory for database, cookies, logs
 RUN mkdir -p /app/data

scripts/download-binaries.mjs

@@ -1,161 +1,751 @@
 #!/usr/bin/env node
 
 /**
- * Download native binaries (ffmpeg + @discordjs/opus) from npmmirror CDN.
- * Called by setup.bat after npm install --ignore-scripts.
+ * Verify / download / repair the native binaries used by TSMusicBot
+ * (ffmpeg-static + @discordjs/opus + better-sqlite3), preferring the
+ * npmmirror CDN so China users never have to reach GitHub.
+ *
+ * Called by setup.bat / setup.sh after `npm install --ignore-scripts`.
+ *
+ * WHY THIS IS NOT JUST A DOWNLOADER
+ * ---------------------------------
+ * A compiled addon only loads into the exact Node ABI it was built for
+ * (process.versions.modules: Node 20 = 115, Node 22 = 127, Node 24 = 137).
+ * better-sqlite3 stores its addon at an ABI-agnostic path
+ * (build/Release/better_sqlite3.node), so a "file exists and is big enough"
+ * check happily keeps a binary built for a *different* Node major around and
+ * the bot then dies with `NODE_MODULE_VERSION 137 ... requires 127`.
+ * So we validate by actually LOADING each package — in a short-lived child
+ * process, because on Windows a loaded .node stays mapped and the OS then
+ * refuses to delete or overwrite it.
+ *
+ * Every repair is staged and swapped in atomically: if a download fails we put
+ * the previous file back, so a failed run can never leave the install in a
+ * worse state than it started.
  *
  * Usage: node scripts/download-binaries.mjs [cdn_base_url]
+ * Env:   TSMB_BINARY_LOG_STDOUT=1  also echo progress to stdout
+ *        (setup.bat uses this to show progress live on stderr while stdout
+ *         is redirected into setup.log)
  */
 
-import { existsSync, mkdirSync, writeFileSync, statSync } from "node:fs";
+import {
+  chmodSync,
+  createWriteStream,
+  existsSync,
+  mkdirSync,
+  mkdtempSync,
+  readdirSync,
+  readFileSync,
+  renameSync,
+  rmSync,
+  statSync,
+  writeFileSync,
+} from "node:fs";
 import { tmpdir } from "node:os";
-import { join, dirname } from "node:path";
+import { basename, dirname, join } from "node:path";
 import { createGunzip } from "node:zlib";
 import { pipeline } from "node:stream/promises";
-import { createWriteStream } from "node:fs";
 import { get } from "node:https";
 import { Readable } from "node:stream";
-import { execSync } from "node:child_process";
+import { execFileSync, execSync } from "node:child_process";
 import { createRequire } from "node:module";
 import { fileURLToPath } from "node:url";
+import { createLineWriter } from "./lib/console-log.mjs";
 
 const ROOT = join(dirname(fileURLToPath(import.meta.url)), "..");
+const NODE_MODULES = join(ROOT, "node_modules");
+const BACKUP_DIR = join(NODE_MODULES, ".tsmusicbot-backup");
+const STAMP_FILE = join(NODE_MODULES, ".tsmusicbot-abi");
+
 const CDN = process.argv[2] || "https://cdn.npmmirror.com/binaries";
 const PLATFORM = process.platform;
 const ARCH = process.arch;
 const NODE_ABI = process.versions.modules;
+const NODE_MAJOR = Number(process.versions.node.split(".")[0]);
+/** The newest Node major this project is regularly tested against, and the one
+ *  every required addon currently ships a prebuild for. Keep in sync with
+ *  TESTED_NODE_MAJOR in scripts/setup.bat. */
+const TESTED_NODE_MAJOR = 22;
 
-function download(url) {
+/** Modules the bot cannot start without. ffmpeg-static is optional: a system
+ *  ffmpeg on PATH is a documented fallback, so it only ever produces a WARN. */
+const REQUIRED = new Set(["@discordjs/opus", "better-sqlite3"]);
+
+/** ffmpeg-static ships ~40-90 MB depending on platform; anything under this is
+ *  certainly a truncated download, not a real build. */
+const FFMPEG_MIN_BYTES = 20 * 1024 * 1024;
+
+// ---------------------------------------------------------------------------
+// logging
+// ---------------------------------------------------------------------------
+
+// Progress goes to stderr so setup.bat can show it live while stdout is being
+// appended to setup.log. TSMB_BINARY_LOG_STDOUT=1 mirrors it into stdout so the
+// log keeps the full transcript too.
+const ECHO_STDOUT = process.env.TSMB_BINARY_LOG_STDOUT === "1";
+
+// Both writers swallow a failed write instead of letting it become an uncaught
+// 'error' event: a console that cannot print the Chinese half of a line (issue
+// #152) must not be able to abort a whole setup run. The two streams degrade
+// independently, so setup.log keeps the full bilingual transcript either way.
+const writeErr = createLineWriter(process.stderr);
+const writeOut = createLineWriter(process.stdout);
+
+function log(msg) {
+  const line = msg === "" ? "" : `  [binary] ${msg}`;
+  writeErr(line);
+  if (ECHO_STDOUT) writeOut(line);
+}
+
+// ---------------------------------------------------------------------------
+// small helpers
+// ---------------------------------------------------------------------------
+
+function sizeOf(filePath) {
+  try {
+    return statSync(filePath).size;
+  } catch {
+    return 0;
+  }
+}
+
+function humanSize(filePath) {
+  const bytes = sizeOf(filePath);
+  if (!bytes) return "unknown size";
+  return bytes >= 1024 * 1024
+    ? `${(bytes / 1024 / 1024).toFixed(1)} MB`
+    : `${(bytes / 1024).toFixed(0)} KB`;
+}
+
+function ensureExecutable(filePath) {
+  if (PLATFORM === "win32") return;
+  try {
+    chmodSync(filePath, 0o755);
+  } catch {
+    /* best effort */
+  }
+}
+
+/** Read the version actually present in node_modules (never hardcode it: the
+ *  lockfile can be far ahead of whatever version this script was written for,
+ *  and a wrong version means a 404 on the CDN). */
+function readInstalledVersion(spec) {
+  try {
+    const pkgJson = join(NODE_MODULES, ...spec.split("/"), "package.json");
+    const version = JSON.parse(readFileSync(pkgJson, "utf8")).version;
+    return typeof version === "string" && version ? version : null;
+  } catch {
+    return null;
+  }
+}
+
+function summarizeError(text) {
+  const lines = String(text || "")
+    .split(/\r?\n/)
+    .map((l) => l.trim())
+    .filter(Boolean);
+  const interesting = lines.find((l) => /NODE_MODULE_VERSION|Error:|error:/.test(l));
+  return (interesting || lines[0] || "unknown error").slice(0, 300);
+}
+
+// ---------------------------------------------------------------------------
+// download
+// ---------------------------------------------------------------------------
+
+function download(url, redirects = 0) {
   return new Promise((resolve, reject) => {
     const req = get(url, { timeout: 120000 }, (res) => {
-      if (res.statusCode < 200 || res.statusCode >= 400) {
-        reject(new Error(`HTTP ${res.statusCode}: ${url}`));
+      const { statusCode, headers } = res;
+      if (statusCode >= 300 && statusCode < 400 && headers.location) {
+        res.resume();
+        if (redirects >= 5) {
+          reject(new Error(`too many redirects: ${url}`));
+          return;
+        }
+        resolve(download(new URL(headers.location, url).toString(), redirects + 1));
+        return;
+      }
+      if (statusCode < 200 || statusCode >= 300) {
+        res.resume();
+        reject(new Error(`HTTP ${statusCode}: ${url}`));
         return;
       }
       const chunks = [];
       res.on("data", (c) => chunks.push(c));
+      res.on("error", reject);
       res.on("end", () => resolve(Buffer.concat(chunks)));
     });
     req.on("error", reject);
-    req.on("timeout", () => { req.destroy(); reject(new Error("timeout")); });
+    req.on("timeout", () => {
+      req.destroy();
+      reject(new Error(`timeout: ${url}`));
+    });
   });
 }
 
-function log(msg) {
-  console.log(`  [binary] ${msg}`);
+let tarModule = null;
+
+/** `tar` is not a declared dependency — it only resolves transitively through
+ *  prebuild-install / @discordjs/node-pre-gyp. Fail with a sentence a user can
+ *  act on instead of a raw MODULE_NOT_FOUND stack. */
+function loadTar() {
+  if (tarModule) return tarModule;
+  try {
+    tarModule = createRequire(import.meta.url)("tar");
+  } catch {
+    throw new Error(
+      "'tar' module not available / 找不到 tar 模块 — run `npm install tar` in the project root and retry",
+    );
+  }
+  return tarModule;
 }
 
-function isValidSize(filePath, minBytes) {
-  try { return statSync(filePath).size >= minBytes; } catch { return false; }
+async function extractTarGz(buf, cwd) {
+  const tar = loadTar();
+  const tmpFile = join(tmpdir(), `tsmb-${process.pid}-${Date.now()}.tar.gz`);
+  writeFileSync(tmpFile, buf);
+  try {
+    await tar.extract({ cwd, file: tmpFile });
+  } finally {
+    try {
+      rmSync(tmpFile, { force: true });
+    } catch {
+      /* ignore */
+    }
+  }
 }
 
-async function downloadFfmpeg() {
-  const ffDir = join(ROOT, "node_modules", "ffmpeg-static");
+// ---------------------------------------------------------------------------
+// load probe (the whole point of this rewrite)
+// ---------------------------------------------------------------------------
+
+/**
+ * The snippet that actually forces each package's addon to be dlopen()ed.
+ * NOTE: better-sqlite3 loads its .node lazily, inside the Database constructor
+ * (lib/database.js: `DEFAULT_ADDON || (DEFAULT_ADDON = require('bindings')(...))`),
+ * so a bare `require('better-sqlite3')` succeeds even against a wrong-ABI binary.
+ * Opening an in-memory database is the cheapest way to really load it.
+ */
+const PROBE_EXPR = {
+  "@discordjs/opus": "require('@discordjs/opus')",
+  "better-sqlite3": "new (require('better-sqlite3'))(':memory:').close()",
+};
+
+/**
+ * Try to load a package in a throwaway child process.
+ * Child process on purpose: loading an addon here would keep the DLL mapped and
+ * Windows would then refuse to rename/delete the file we are about to replace.
+ */
+function probeRequire(spec) {
+  const expr = PROBE_EXPR[spec] || `require(${JSON.stringify(spec)})`;
+  try {
+    execFileSync(process.execPath, ["-e", expr], {
+      cwd: ROOT,
+      stdio: "pipe",
+      timeout: 120000,
+      windowsHide: true,
+    });
+    return { ok: true };
+  } catch (err) {
+    const text = [err.stderr && err.stderr.toString(), err.message].filter(Boolean).join("\n");
+    // "...compiled against ... NODE_MODULE_VERSION 137. This version of Node.js
+    //  requires NODE_MODULE_VERSION 127..."  -> first number is what it was built for.
+    const abis = [...text.matchAll(/NODE_MODULE_VERSION (\d+)/g)].map((m) => m[1]);
+    return {
+      ok: false,
+      abiMismatch: abis.length >= 2,
+      compiledAbi: abis.length >= 2 ? abis[0] : null,
+      error: summarizeError(text),
+    };
+  }
+}
+
+function describeProbe(probe) {
+  if (probe.abiMismatch) {
+    return `built for Node ABI ${probe.compiledAbi}, but this Node needs ABI ${NODE_ABI}`;
+  }
+  return probe.error;
+}
+
+function probeFfmpegBinary(bin) {
+  try {
+    const out = execFileSync(bin, ["-version"], {
+      stdio: "pipe",
+      timeout: 30000,
+      windowsHide: true,
+    }).toString();
+    return { ok: true, version: (out.split(/\r?\n/)[0] || "").slice(0, 60) };
+  } catch (err) {
+    const text = [err.stderr && err.stderr.toString(), err.message].filter(Boolean).join("\n");
+    return { ok: false, error: summarizeError(text) };
+  }
+}
+
+// ---------------------------------------------------------------------------
+// atomic swap helpers
+// ---------------------------------------------------------------------------
+
+let stashCounter = 0;
+
+/**
+ * Move `target` (file or directory) out of the way into node_modules/.tsmusicbot-backup.
+ * Same volume as node_modules, so the rename is atomic, and outside the package's
+ * build/ tree so that `npm rebuild` / `node-gyp clean` cannot wipe the backup.
+ * Returns { commit, restore } — call exactly one of them.
+ */
+/** Windows likes to hold a brief lock on a freshly written .node (antivirus,
+ *  indexer), and rmSync does not retry by default. */
+const RM_OPTS = { recursive: true, force: true, maxRetries: 5, retryDelay: 150 };
+
+function stash(target) {
+  if (!existsSync(target)) {
+    return { commit() {}, restore() {} };
+  }
+  mkdirSync(BACKUP_DIR, { recursive: true });
+  const backup = join(BACKUP_DIR, `${basename(target)}.${process.pid}.${stashCounter++}.bak`);
+  rmSync(backup, RM_OPTS);
+  renameSync(target, backup);
+  // The backup filename alone cannot say where the artifact came from, and a
+  // run that is killed (Ctrl+C during a slow download) never reaches commit or
+  // restore. Record the target so the next run can put it back — see
+  // recoverOrphanedBackups().
+  const manifest = `${backup}.json`;
+  try {
+    writeFileSync(manifest, `${JSON.stringify({ target })}\n`);
+  } catch {
+    /* recovery is best-effort; the swap itself still works */
+  }
+
+  let settled = false;
+  const dropManifest = () => {
+    try {
+      rmSync(manifest, RM_OPTS);
+    } catch {
+      /* ignore */
+    }
+  };
+  return {
+    commit() {
+      if (settled) return;
+      settled = true;
+      try {
+        rmSync(backup, RM_OPTS);
+      } catch {
+        /* leftover backup is harmless */
+      }
+      dropManifest();
+    },
+    restore() {
+      if (settled) return;
+      settled = true;
+      try {
+        rmSync(target, RM_OPTS);
+        mkdirSync(dirname(target), { recursive: true });
+        renameSync(backup, target);
+        dropManifest();
+        log(`restored the previous ${basename(target)} — nothing was made worse`);
+      } catch (err) {
+        // Leave the backup AND its manifest in place: recoverOrphanedBackups()
+        // on the next run is the second chance.
+        log(`WARN: could not restore ${target} from ${backup}: ${err.message}`);
+        log(`WARN: the previous file is still at ${backup} — the next run will try again`);
+      }
+    },
+  };
+}
+
+/**
+ * Put back anything a previous run stashed but never restored — a run killed
+ * mid-download, or one whose restore() itself failed. Only acts when the target
+ * is currently absent, so it can never clobber a good binary.
+ */
+function recoverOrphanedBackups() {
+  if (!existsSync(BACKUP_DIR)) return;
+  let entries;
+  try {
+    entries = readdirSync(BACKUP_DIR);
+  } catch {
+    return;
+  }
+  for (const entry of entries) {
+    if (!entry.endsWith(".json")) continue;
+    const manifest = join(BACKUP_DIR, entry);
+    const backup = manifest.slice(0, -".json".length);
+    try {
+      const { target } = JSON.parse(readFileSync(manifest, "utf8"));
+      if (!target || !existsSync(backup)) {
+        rmSync(manifest, RM_OPTS);
+        continue;
+      }
+      if (existsSync(target)) continue; // a good file is already there — leave it alone
+      mkdirSync(dirname(target), { recursive: true });
+      renameSync(backup, target);
+      rmSync(manifest, RM_OPTS);
+      log(`recovered ${basename(target)} left behind by an interrupted run`);
+    } catch (err) {
+      log(`WARN: could not process leftover backup ${entry}: ${err.message}`);
+    }
+  }
+}
+
+function cleanupBackupDir() {
+  try {
+    if (existsSync(BACKUP_DIR) && readdirSync(BACKUP_DIR).length === 0) {
+      rmSync(BACKUP_DIR, { recursive: true, force: true });
+    }
+  } catch {
+    /* ignore */
+  }
+}
+
+// ---------------------------------------------------------------------------
+// per-module results
+// ---------------------------------------------------------------------------
+
+/** status: "ok" | "repaired" | "failed" | "missing" */
+function makeResult(name, status, detail) {
+  return { name, required: REQUIRED.has(name), status, detail };
+}
+
+function buildFromSource(command) {
+  // stdout -> inherited (setup.bat sends it to the log), stderr -> inherited so
+  // compiler progress stays visible; npm's own output is far too noisy to buffer.
+  execSync(command, { cwd: ROOT, stdio: ["ignore", "inherit", "inherit"] });
+}
+
+/**
+ * A 404 from the CDN is not a mirror outage: it means this exact package
+ * version publishes no prebuilt binary for the running Node ABI at all.
+ * @discordjs/opus 0.10.0 has no build for Node 24 (ABI 137), so a user on that
+ * major lands in the source-build fallback below and is told to install Python
+ * and a C++ toolchain. Switching Node major is the far cheaper fix, and nothing
+ * else in this output points at it. (better-sqlite3 dropping its Node 20 / ABI
+ * 115 builds in 12.10.0 is why Node 20 is no longer accepted at all.)
+ * See issue #152.
+ */
+function explainMissingPrebuild(name, version, err) {
+  if (!/HTTP 404/.test(err.message)) return;
+  log(`${name}: ${name}@${version} ships no prebuilt binary for Node ${NODE_MAJOR} (ABI ${NODE_ABI})`);
+  log(
+    `${name}: Node ${TESTED_NODE_MAJOR} LTS has one — switching Node is usually much quicker than ` +
+      `setting up a compiler (换用 Node ${TESTED_NODE_MAJOR} LTS 通常比装编译环境快得多)`,
+  );
+}
+
+function buildToolsHint() {
+  log("Install build tools first:");
+  log("  Windows: npm install --global windows-build-tools  (或安装 Visual Studio Build Tools + Python)");
+  log("  Ubuntu/Debian: sudo apt install build-essential python3");
+  log("  CentOS/RHEL:   sudo yum groupinstall 'Development Tools'");
+}
+
+// ---------------------------------------------------------------------------
+// ffmpeg-static (OPTIONAL — a system ffmpeg is a documented fallback)
+// ---------------------------------------------------------------------------
+
+async function ensureFfmpeg() {
+  const name = "ffmpeg-static";
+  const ffDir = join(NODE_MODULES, name);
   const ffName = PLATFORM === "win32" ? "ffmpeg.exe" : "ffmpeg";
   const ffDest = join(ffDir, ffName);
 
-  if (!existsSync(ffDir)) { log("ffmpeg-static not installed, skipping"); return false; }
-  if (existsSync(ffDest)) {
-    if (isValidSize(ffDest, 50 * 1024 * 1024)) {
-      log("ffmpeg already exists, skipping");
-      return true;
+  if (!existsSync(ffDir)) {
+    log(`${name}: package not installed, skipping (a system ffmpeg on PATH also works)`);
+    return makeResult(name, "missing", "package not installed");
+  }
+
+  if (existsSync(ffDest) && sizeOf(ffDest) >= FFMPEG_MIN_BYTES) {
+    ensureExecutable(ffDest);
+    const probe = probeFfmpegBinary(ffDest);
+    if (probe.ok) {
+      log(`${name}: OK (${humanSize(ffDest)}, ${probe.version})`);
+      return makeResult(name, "ok", humanSize(ffDest));
     }
-    log("ffmpeg exists but seems corrupted (too small), re-downloading...");
+    // Deliberately NOT re-downloading here: ffmpeg is a plain executable with no
+    // ABI to mismatch, and forcing an ~80 MB re-download because `-version`
+    // could not be spawned would hurt exactly the slow-network users this
+    // script exists for.
+    log(`${name}: present (${humanSize(ffDest)}) but could not be executed: ${probe.error}`);
+    return makeResult(name, "ok", "present, not verified");
+  }
+
+  if (existsSync(ffDest)) {
+    log(`${name}: existing ffmpeg looks truncated (${humanSize(ffDest)}), re-downloading...`);
+  } else {
+    log(`${name}: ffmpeg binary missing, downloading...`);
   }
 
   const url = `${CDN}/ffmpeg-static/b6.1.1/ffmpeg-${PLATFORM}-${ARCH}.gz`;
-  log("Downloading ffmpeg...");
-  const buf = await download(url);
-  await pipeline(Readable.from(buf), createGunzip(), createWriteStream(ffDest));
-  try { execSync(`chmod +x "${ffDest}"`); } catch {}
-  const size = ((await statSync(ffDest)).size / 1024 / 1024).toFixed(1);
-  log(`ffmpeg OK (${size} MB)`);
-  return true;
-}
-
-async function downloadOpus() {
-  const opusDir = join(ROOT, "node_modules", "@discordjs", "opus");
-  const prebuildName = `node-v${NODE_ABI}-napi-v3-${PLATFORM}-${ARCH}-unknown-unknown`;
-  const opusDest = join(opusDir, "prebuild", prebuildName, "opus.node");
-
-  if (!existsSync(opusDir)) { log("@discordjs/opus not installed, skipping"); return false; }
-  if (existsSync(opusDest)) {
-    if (isValidSize(opusDest, 100 * 1024)) {
-      log("@discordjs/opus already exists, skipping");
-      return true;
-    }
-    log("@discordjs/opus exists but seems corrupted (too small), re-downloading...");
-  }
-
-  const url = `${CDN}/@discordjs/opus/v0.10.0/opus-v0.10.0-node-v${NODE_ABI}-napi-v3-${PLATFORM}-${ARCH}-unknown-unknown.tar.gz`;
-  log("Downloading @discordjs/opus...");
+  const backup = stash(ffDest);
+  const tmpDest = `${ffDest}.tsmb-tmp-${process.pid}`;
   try {
+    log(`${name}: GET ${url}  (~80 MB, 这一步比较慢,请耐心等待)`);
     const buf = await download(url);
-    mkdirSync(dirname(opusDest), { recursive: true });
-    const require = createRequire(import.meta.url);
-    const tar = require("tar");
-    const tmpFile = join(tmpdir(), `discordjs-opus-${Date.now()}.tar.gz`);
-    writeFileSync(tmpFile, buf);
-    await tar.extract({ cwd: join(opusDir, "prebuild"), file: tmpFile });
-    log("@discordjs/opus OK");
-    return true;
+    await pipeline(Readable.from(buf), createGunzip(), createWriteStream(tmpDest));
+    ensureExecutable(tmpDest);
+    if (sizeOf(tmpDest) < FFMPEG_MIN_BYTES) {
+      throw new Error(`downloaded ffmpeg is only ${humanSize(tmpDest)} — truncated`);
+    }
+    renameSync(tmpDest, ffDest); // atomic swap, same directory
+    backup.commit();
+    log(`${name}: OK (${humanSize(ffDest)})`);
+    return makeResult(name, "repaired", humanSize(ffDest));
   } catch (err) {
-    log(`CDN download failed (${err.message}), trying to build from source...`);
     try {
-      execSync("npm rebuild @discordjs/opus", { cwd: ROOT, stdio: "inherit" });
-      if (existsSync(opusDest) && isValidSize(opusDest, 100 * 1024)) {
-        log("@discordjs/opus built from source OK");
-        return true;
+      rmSync(tmpDest, { force: true });
+    } catch {
+      /* ignore */
+    }
+    backup.restore();
+    log(`${name}: download failed — ${err.message}`);
+    log(`${name}: not fatal — install ffmpeg system-wide and put it on PATH instead`);
+    return makeResult(name, "failed", err.message);
+  }
+}
+
+// ---------------------------------------------------------------------------
+// @discordjs/opus (REQUIRED)
+// ---------------------------------------------------------------------------
+
+async function ensureOpus() {
+  const name = "@discordjs/opus";
+  const pkgDir = join(NODE_MODULES, "@discordjs", "opus");
+  const prebuildRoot = join(pkgDir, "prebuild");
+  // node-pre-gyp resolves this directory from the *running* Node's ABI, so a
+  // stale build for another ABI simply sits at another path and is ignored.
+  const prebuildDirName = `node-v${NODE_ABI}-napi-v3-${PLATFORM}-${ARCH}-unknown-unknown`;
+  const destDir = join(prebuildRoot, prebuildDirName);
+
+  if (!existsSync(pkgDir)) {
+    log(`${name}: package not installed — run 'npm install' first`);
+    return makeResult(name, "missing", "package not installed");
+  }
+
+  const before = probeRequire(name);
+  if (before.ok) {
+    log(`${name}: OK (loads under ${process.version}, ABI ${NODE_ABI})`);
+    return makeResult(name, "ok", `ABI ${NODE_ABI}`);
+  }
+  log(`${name}: unusable — ${describeProbe(before)}`);
+  log(`${name}: installing a build for ABI ${NODE_ABI}...`);
+
+  const version = readInstalledVersion(name) || "0.10.0";
+  const url =
+    `${CDN}/@discordjs/opus/v${version}/opus-v${version}` +
+    `-node-v${NODE_ABI}-napi-v3-${PLATFORM}-${ARCH}-unknown-unknown.tar.gz`;
+
+  const backup = stash(destDir);
+  let staging = null;
+  try {
+    try {
+      log(`${name}: GET ${url}`);
+      const buf = await download(url);
+      staging = mkdtempSync(join(pkgDir, ".tsmb-staging-"));
+      await extractTarGz(buf, staging);
+      const staged = join(staging, prebuildDirName);
+      if (!existsSync(join(staged, "opus.node"))) {
+        throw new Error(`tarball did not contain ${prebuildDirName}/opus.node`);
+      }
+      mkdirSync(prebuildRoot, { recursive: true });
+      rmSync(destDir, { recursive: true, force: true });
+      renameSync(staged, destDir); // atomic swap, same volume
+      log(`${name}: prebuilt binary installed`);
+    } catch (cdnErr) {
+      log(`${name}: CDN install failed (${cdnErr.message})`);
+      explainMissingPrebuild(name, version, cdnErr);
+      log(`${name}: falling back to a source build — 'npm rebuild ${name}' (可能需要几分钟)`);
+      buildFromSource(`npm rebuild ${name}`);
+    }
+
+    const after = probeRequire(name);
+    if (!after.ok) throw new Error(describeProbe(after));
+    backup.commit();
+    log(`${name}: repaired, now loads under ${process.version} (ABI ${NODE_ABI})`);
+    return makeResult(name, "repaired", `ABI ${NODE_ABI}`);
+  } catch (err) {
+    backup.restore();
+    log(`${name}: FAILED — ${err.message}`);
+    buildToolsHint();
+    return makeResult(name, "failed", err.message);
+  } finally {
+    if (staging) {
+      try {
+        rmSync(staging, { recursive: true, force: true });
+      } catch {
+        /* ignore */
       }
-      log("Source build completed but .node file not found");
-      return false;
-    } catch (buildErr) {
-      log(`Source build failed: ${buildErr.message}`);
-      log("Install build tools: sudo apt install build-essential (Ubuntu/Debian)");
-      log("                    sudo yum groupinstall 'Development Tools' (CentOS/RHEL)");
-      return false;
     }
   }
 }
 
-async function downloadBetterSqlite3() {
-  const pkgDir = join(ROOT, "node_modules", "better-sqlite3");
+// ---------------------------------------------------------------------------
+// better-sqlite3 (REQUIRED) — the module the ABI bug actually bites
+// ---------------------------------------------------------------------------
+
+async function ensureBetterSqlite3() {
+  const name = "better-sqlite3";
+  const pkgDir = join(NODE_MODULES, name);
   const dest = join(pkgDir, "build", "Release", "better_sqlite3.node");
 
-  if (!existsSync(pkgDir)) { log("better-sqlite3 not installed, skipping"); return false; }
-  if (existsSync(dest)) {
-    if (isValidSize(dest, 500 * 1024)) {
-      log("better-sqlite3 already exists, skipping");
-      return true;
-    }
-    log("better-sqlite3 exists but seems corrupted (too small), re-downloading...");
+  if (!existsSync(pkgDir)) {
+    log(`${name}: package not installed — run 'npm install' first`);
+    return makeResult(name, "missing", "package not installed");
   }
 
-  const version = "12.8.0";
-  const url = `${CDN}/better-sqlite3/v${version}/better-sqlite3-v${version}-node-v${NODE_ABI}-${PLATFORM}-${ARCH}.tar.gz`;
-  log("Downloading better-sqlite3...");
-  const buf = await download(url);
-  const require = createRequire(import.meta.url);
-  const tar = require("tar");
-  const tmpFile = join(tmpdir(), `better-sqlite3-${Date.now()}.tar.gz`);
-  writeFileSync(tmpFile, buf);
-  mkdirSync(dirname(dest), { recursive: true });
-  await tar.extract({ cwd: pkgDir, file: tmpFile });
-  if (existsSync(dest)) {
-    log(`better-sqlite3 OK (${((await statSync(dest)).size / 1024).toFixed(0)} KB)`);
-    return true;
+  const before = probeRequire(name);
+  if (before.ok) {
+    log(`${name}: OK (loads under ${process.version}, ABI ${NODE_ABI})`);
+    return makeResult(name, "ok", `ABI ${NODE_ABI}`);
+  }
+  // This is the case the old size check could not see: the file is there, it is
+  // ~1.9 MB, and it is completely useless because it targets another ABI.
+  log(`${name}: unusable — ${describeProbe(before)}`);
+  log(`${name}: replacing the native binary with a build for ABI ${NODE_ABI}...`);
+
+  const version = readInstalledVersion(name) || "12.11.1";
+  const url = `${CDN}/${name}/v${version}/${name}-v${version}-node-v${NODE_ABI}-${PLATFORM}-${ARCH}.tar.gz`;
+
+  const backup = stash(dest);
+  let staging = null;
+  try {
+    try {
+      log(`${name}: GET ${url}`);
+      const buf = await download(url);
+      staging = mkdtempSync(join(pkgDir, ".tsmb-staging-"));
+      await extractTarGz(buf, staging);
+      const staged = join(staging, "build", "Release", "better_sqlite3.node");
+      if (!existsSync(staged)) {
+        throw new Error("tarball did not contain build/Release/better_sqlite3.node");
+      }
+      mkdirSync(dirname(dest), { recursive: true });
+      rmSync(dest, { force: true });
+      renameSync(staged, dest); // atomic swap, same volume
+      log(`${name}: prebuilt binary installed (${humanSize(dest)})`);
+    } catch (cdnErr) {
+      log(`${name}: CDN install failed (${cdnErr.message})`);
+      explainMissingPrebuild(name, version, cdnErr);
+      log(`${name}: falling back to a source build — 'npm rebuild ${name} --build-from-source' (可能需要几分钟)`);
+      buildFromSource(`npm rebuild ${name} --build-from-source`);
+    }
+
+    const after = probeRequire(name);
+    if (!after.ok) throw new Error(describeProbe(after));
+    backup.commit();
+    log(`${name}: repaired, now loads under ${process.version} (ABI ${NODE_ABI}, ${humanSize(dest)})`);
+    return makeResult(name, "repaired", `ABI ${NODE_ABI}`);
+  } catch (err) {
+    backup.restore();
+    log(`${name}: FAILED — ${err.message}`);
+    buildToolsHint();
+    return makeResult(name, "failed", err.message);
+  } finally {
+    if (staging) {
+      try {
+        rmSync(staging, { recursive: true, force: true });
+      } catch {
+        /* ignore */
+      }
+    }
   }
-  log("better-sqlite3 extracted but .node file not found at expected path");
-  return false;
 }
 
+// ---------------------------------------------------------------------------
+// stamp
+// ---------------------------------------------------------------------------
+
+/** Record which ABI this install was built for. Lives inside node_modules so it
+ *  dies together with the thing it describes. check-native.mjs reads it. */
+function writeStamp(results) {
+  if (!existsSync(NODE_MODULES)) return;
+  const stamp = {
+    abi: NODE_ABI,
+    nodeVersion: process.version,
+    platform: PLATFORM,
+    arch: ARCH,
+    updatedAt: new Date().toISOString(),
+    modules: Object.fromEntries(results.map((r) => [r.name, r.status])),
+  };
+  try {
+    writeFileSync(STAMP_FILE, `${JSON.stringify(stamp, null, 2)}\n`);
+    log(`ABI stamp written: node_modules/.tsmusicbot-abi (Node ${process.version}, ABI ${NODE_ABI})`);
+  } catch (err) {
+    log(`WARN: could not write ABI stamp: ${err.message}`);
+  }
+}
+
+// ---------------------------------------------------------------------------
+// main
+// ---------------------------------------------------------------------------
+
+const STEPS = [
+  ["ffmpeg-static", ensureFfmpeg],
+  ["@discordjs/opus", ensureOpus],
+  ["better-sqlite3", ensureBetterSqlite3],
+];
+
 try {
-  const results = await Promise.all([downloadFfmpeg(), downloadOpus(), downloadBetterSqlite3()]);
-  if (results.some(Boolean)) {
-    console.log("  [binary] All downloads complete");
+  log(`Node ${process.version} (ABI ${NODE_ABI}), ${PLATFORM}-${ARCH}, CDN ${CDN}`);
+
+  recoverOrphanedBackups();
+
+  // STRICTLY SEQUENTIAL, and it has to stay that way. The source-build fallback
+  // shells out through execSync, which parks the event loop for minutes; the
+  // 120s timeout that download() arms is a socket-INACTIVITY timer sitting on
+  // that same loop. Run these concurrently and the first module to fall back to
+  // a source build kills every download still in flight — the connection is
+  // healthy, the timer just never got a chance to be reset. That is not a rare
+  // race: @discordjs/opus 0.10.0 has no prebuild for ABI 137, so on Node 24 that
+  // module 404s within ~100ms and starts building while ffmpeg's ~80MB download
+  // is still going. ffmpeg is optional,
+  // so the spurious failure used to be swallowed as a WARN and setup still
+  // reported success — leaving the user with no ffmpeg and no working playback.
+  // Nothing here benefits from overlap anyway: every probe is execFileSync.
+  const results = [];
+  for (const [name, run] of STEPS) {
+    try {
+      results.push(await run());
+    } catch (err) {
+      results.push(makeResult(name, "failed", err?.message ?? String(err)));
+    }
+  }
+
+  cleanupBackupDir();
+
+  log("");
+  log(`Summary — Node ${process.version} / ABI ${NODE_ABI} / ${PLATFORM}-${ARCH}:`);
+  for (const r of results) {
+    const tag =
+      r.status === "ok"
+        ? "OK"
+        : r.status === "repaired"
+          ? "REPAIRED"
+          : r.required
+            ? "FAILED"
+            : "WARN (optional)";
+    log(`  - ${r.name.padEnd(17)} ${tag}${r.detail ? `  ${r.detail}` : ""}`);
+  }
+
+  const broken = results.filter(
+    (r) => r.required && r.status !== "ok" && r.status !== "repaired",
+  );
+  // Only stamp a build that actually succeeded. The stamp says "node_modules is
+  // built for ABI X"; writing it after a failed repair would have check-native
+  // print a reassuring "built with ABI 137" right above its own "this module is
+  // built for ABI 127" complaint.
+  if (broken.length === 0) writeStamp(results);
+  // process.exitCode rather than process.exit(): setup.bat redirects stdout to
+  // setup.log, and process.exit() can drop output that has not flushed yet.
+  if (broken.length > 0) {
+    log("");
+    log(`ERROR: required native module(s) unusable: ${broken.map((r) => r.name).join(", ")}`);
+    log("必需的原生模块不可用,机器人无法启动 —— 请查看上面的错误信息。");
+    process.exitCode = 1;
+  } else {
+    log("All required native modules are ready.");
+    process.exitCode = 0;
   }
 } catch (e) {
-  console.error(`  [binary] ERROR: ${e.message}`);
-  process.exit(1);
+  log(`ERROR: ${e.stack || e.message}`);
+  process.exitCode = 1;
 }
-

scripts/lib/console-log.mjs

@@ -0,0 +1,142 @@
+/**
+ * Crash-proof line logging for the setup scripts.
+ *
+ * WHY THIS EXISTS (issue #152)
+ * ----------------------------
+ * setup.bat runs `chcp 65001` and shows progress on stderr. Some Windows
+ * consoles - Windows Server 2012 R2 above all - cannot render non-ASCII text in
+ * that code page and the OS fails the write with EIO. `process.stderr` is an
+ * ordinary stream, so that EIO arrives as an 'error' event, and a stream with
+ * no 'error' listener rethrows it as an uncaught exception:
+ *
+ *     Error: write EIO
+ *         at afterWriteDispatched (node:internal/stream_base_commons:159:15)
+ *         ...
+ *         at log (scripts/download-binaries.mjs:84:18)
+ *         at ensureFfmpeg (scripts/download-binaries.mjs:451:5)
+ *
+ * That is setup killing itself inside its own progress logging, on the first
+ * line of the run that happened to contain Chinese - nothing was wrong with the
+ * download it was about to start.
+ *
+ * So: listen for the error and degrade instead of dying.
+ *   full  -> ascii : drop the CJK the console choked on, keep the English half
+ *   ascii -> off   : the stream is simply gone (closed pipe) - stay quiet
+ * Each stream degrades on its own, so a console that gives up does not cost
+ * setup.log its full bilingual transcript: that stdout is a redirected file.
+ */
+
+const HAS_NON_ASCII = /[^\x00-\x7F]/;
+
+/** Placeholders for a removed run: one that separated words, one that did not. */
+const SPACED = "\u0000";
+const TIGHT = "\u0001";
+
+/** Punctuation the bilingual strings use that has an obvious ASCII twin. */
+const PUNCTUATION = new Map(
+  Object.entries({
+    "—": "-",
+    "–": "-",
+    "…": "...",
+    "“": '"',
+    "”": '"',
+    "‘": "'",
+    "’": "'",
+    "，": ",",
+    "。": ".",
+    "、": ",",
+    "：": ":",
+    "；": ";",
+    "（": "(",
+    "）": ")",
+    "！": "!",
+    "？": "?",
+    "←": "<-",
+    "→": "->",
+    "×": "x",
+  }),
+);
+
+/**
+ * Best-effort ASCII rendering of a log line, for a console that cannot print
+ * anything else. Returns null when nothing worth printing survives - every
+ * Chinese-only line in these scripts sits directly beside an English line
+ * saying the same thing, so dropping it loses no information.
+ */
+export function toAsciiFallback(text) {
+  if (!HAS_NON_ASCII.test(text)) return text;
+
+  let out = "";
+  for (const ch of text) out += PUNCTUATION.get(ch) ?? ch;
+
+  out = out
+    .replace(/[\u0000\u0001]/g, "")
+    // Mark each removed run rather than just deleting it, so the tidy-up below
+    // can tell "a separator that introduced text we dropped" from "a separator
+    // that belongs to the English half". SPACED was holding two ASCII words
+    // apart; TIGHT was hugging a bracket or a comma.
+    .replace(/[ \t]*[^\x00-\x7F]+[ \t]*/g, (run) =>
+      /^[ \t]/.test(run) && /[ \t]$/.test(run) ? SPACED : TIGHT,
+    )
+    // "(可能需要几分钟)" — the parentheses held nothing else.
+    .replace(/[ \t]*\([ \t]*(?:[\u0000\u0001][ \t]*)+\)/g, "")
+    // "FAILED — 编译失败", "(~80 MB, 请耐心等待)" — drop the trailing marks along
+    // with the separators that were only ever there to introduce them.
+    .replace(/[ \t]*[-,;:]*[ \t]*(?:[\u0000\u0001][ \t,;:-]*)+(?=[)\]]|$)/gm, "")
+    .replace(/\u0000/g, " ")
+    .replace(/\u0001/g, "")
+    .replace(/[ \t]+$/gm, "");
+
+  return /[A-Za-z0-9]/.test(out) ? out : null;
+}
+
+/** One degradation state per stream, shared by every writer built on it. */
+const guards = new WeakMap();
+
+function guardFor(stream) {
+  const existing = guards.get(stream);
+  if (existing) return existing;
+
+  const guard = { mode: "full" };
+  guards.set(stream, guard);
+  try {
+    // The whole point: without this listener the next EIO/EPIPE is fatal.
+    stream.on("error", () => degrade(guard));
+  } catch {
+    /* not an EventEmitter - the try/catch around write() still guards us */
+  }
+  return guard;
+}
+
+function degrade(guard) {
+  guard.mode = guard.mode === "full" ? "ascii" : "off";
+}
+
+/**
+ * Build a `writeLine(text)` that appends a newline, never throws, and never
+ * lets a failed console write take the process down with it.
+ * Returns true when the line reached the stream.
+ */
+export function createLineWriter(stream) {
+  const guard = guardFor(stream);
+
+  return function writeLine(text) {
+    if (guard.mode === "off") return false;
+
+    let line = text;
+    if (guard.mode === "ascii") {
+      line = toAsciiFallback(text);
+      if (line === null) return false;
+    }
+
+    try {
+      stream.write(`${line}\n`);
+      return true;
+    } catch {
+      // A synchronous throw (EBADF on a closed handle) never reaches the
+      // 'error' listener, so degrade here too.
+      degrade(guard);
+      return false;
+    }
+  };
+}

scripts/lib/console-log.test.mjs

@@ -0,0 +1,133 @@
+import { EventEmitter } from "node:events";
+import { describe, expect, it, vi } from "vitest";
+
+import { createLineWriter, toAsciiFallback } from "./console-log.mjs";
+
+/** Stand-in for process.stderr: an EventEmitter with a write() we can steer. */
+function fakeStream() {
+  const stream = new EventEmitter();
+  stream.written = [];
+  stream.throwOnWrite = false;
+  stream.write = (chunk) => {
+    if (stream.throwOnWrite) throw new Error("EBADF");
+    stream.written.push(chunk);
+    return true;
+  };
+  return stream;
+}
+
+describe("toAsciiFallback", () => {
+  it("leaves ASCII lines exactly as they are", () => {
+    const line = "  [binary] better-sqlite3: OK (loads under v22.23.2, ABI 127)";
+    expect(toAsciiFallback(line)).toBe(line);
+    expect(toAsciiFallback("")).toBe("");
+  });
+
+  it("keeps the English half of the line that crashed setup in #152", () => {
+    expect(
+      toAsciiFallback(
+        "  [binary] ffmpeg-static: GET https://cdn/ffmpeg.gz  (~80 MB, 这一步比较慢,请耐心等待)",
+      ),
+    ).toBe("  [binary] ffmpeg-static: GET https://cdn/ffmpeg.gz  (~80 MB)");
+  });
+
+  it("drops parentheses and separators left stranded by the removed text", () => {
+    expect(
+      toAsciiFallback("  [binary] better-sqlite3: falling back — 'npm rebuild' (可能需要几分钟)"),
+    ).toBe("  [binary] better-sqlite3: falling back - 'npm rebuild'");
+    expect(
+      toAsciiFallback("  Windows: npm install --global windows-build-tools  (或安装 VS Build Tools)"),
+    ).toBe("  Windows: npm install --global windows-build-tools  (VS Build Tools)");
+  });
+
+  it("drops a Chinese-only line, which always has an English twin beside it", () => {
+    expect(toAsciiFallback("必需的原生模块不可用,机器人无法启动 —— 请查看上面的错误信息。")).toBeNull();
+  });
+
+  it("preserves the indentation the summary is aligned on, and drops the dangling dash", () => {
+    expect(toAsciiFallback("  - better-sqlite3     FAILED — 编译失败")).toBe(
+      "  - better-sqlite3     FAILED",
+    );
+  });
+
+  it("keeps a separator that belongs to the English half", () => {
+    expect(toAsciiFallback("Summary — Node v22.0.0 / ABI 127 / win32-x64:")).toBe(
+      "Summary - Node v22.0.0 / ABI 127 / win32-x64:",
+    );
+  });
+});
+
+describe("createLineWriter", () => {
+  it("appends a newline and reports the write", () => {
+    const stream = fakeStream();
+    expect(createLineWriter(stream)("hello")).toBe(true);
+    expect(stream.written).toEqual(["hello\n"]);
+  });
+
+  it("survives the EIO that killed setup: an 'error' event must not throw", () => {
+    const stream = fakeStream();
+    createLineWriter(stream);
+    expect(stream.listenerCount("error")).toBe(1);
+    expect(() => stream.emit("error", Object.assign(new Error("write EIO"), { code: "EIO" }))).not.toThrow();
+  });
+
+  it("falls back to ASCII once the console has refused a line", () => {
+    const stream = fakeStream();
+    const write = createLineWriter(stream);
+    write("  [binary] GET https://cdn/ffmpeg.gz  (~80 MB, 这一步比较慢,请耐心等待)");
+    stream.emit("error", new Error("write EIO"));
+    write("  [binary] GET https://cdn/opus.tar.gz  (~1 MB, 这一步比较慢,请耐心等待)");
+    expect(stream.written).toEqual([
+      "  [binary] GET https://cdn/ffmpeg.gz  (~80 MB, 这一步比较慢,请耐心等待)\n",
+      "  [binary] GET https://cdn/opus.tar.gz  (~1 MB)\n",
+    ]);
+  });
+
+  it("goes quiet after a second failure rather than retrying a dead stream", () => {
+    const stream = fakeStream();
+    const write = createLineWriter(stream);
+    stream.emit("error", new Error("write EIO"));
+    stream.emit("error", new Error("write EPIPE"));
+    expect(write("anything at all")).toBe(false);
+    expect(stream.written).toEqual([]);
+  });
+
+  it("degrades on a synchronous throw too, which never reaches the listener", () => {
+    const stream = fakeStream();
+    const write = createLineWriter(stream);
+    stream.throwOnWrite = true;
+    expect(write("  [binary] 下载中 downloading")).toBe(false);
+    stream.throwOnWrite = false;
+    write("  [binary] 下载中 downloading");
+    expect(stream.written).toEqual(["  [binary] downloading\n"]);
+  });
+
+  it("degrades each stream on its own, so setup.log keeps the full transcript", () => {
+    const console_ = fakeStream();
+    const logFile = fakeStream();
+    const writeConsole = createLineWriter(console_);
+    const writeLog = createLineWriter(logFile);
+    console_.emit("error", new Error("write EIO"));
+
+    const line = "  [binary] ffmpeg-static: 下载完成 done";
+    writeConsole(line);
+    writeLog(line);
+
+    expect(console_.written).toEqual(["  [binary] ffmpeg-static: done\n"]);
+    expect(logFile.written).toEqual([`${line}\n`]);
+  });
+
+  it("never installs a second listener for a stream that already has a writer", () => {
+    const stream = fakeStream();
+    createLineWriter(stream);
+    createLineWriter(stream);
+    expect(stream.listenerCount("error")).toBe(1);
+  });
+
+  it("still guards a stream that is not an EventEmitter", () => {
+    const stream = { write: vi.fn(() => { throw new Error("EBADF"); }) };
+    const write = createLineWriter(stream);
+    expect(() => write("line")).not.toThrow();
+    expect(write("line")).toBe(false);
+  });
+});

scripts/setup.bat

@@ -10,8 +10,11 @@ title TSMusicBot Setup
 ::  - 自动修复 PowerShell 环境变量
 :: ============================================================
 
-set "SCRIPT_VERSION=2.1"
-set "MIN_NODE_MAJOR=20"
+set "SCRIPT_VERSION=2.2"
+set "MIN_NODE_MAJOR=22"
+:: Newest Node major this project is regularly tested against. Anything above
+:: still works, it just may have no prebuilt addons and fall back to a source build.
+set "TESTED_NODE_MAJOR=22"
 set "LOG_FILE=%~dp0..\setup.log"
 set "FAILED=0"
 
@@ -64,13 +67,40 @@ for /f "tokens=1 delims=v." %%a in ("%NODE_VER%") do set "NODE_MAJOR=%%a"
 call :log "Node.js version: %NODE_VER%"
 echo [OK] Node.js found: %NODE_VER%
 
-if %NODE_MAJOR% LSS %MIN_NODE_MAJOR% (
-    call :error "Node.js version too old. Need %MIN_NODE_MAJOR%+, found %NODE_VER%."
+:: The supported floor is not just a major version, so let node decide.
+:: Node 20 was dropped: better-sqlite3 ships no prebuilt binary for its ABI
+:: (115) since 12.10.0, so every Node 20 install needed Python and a C++
+:: toolchain just to get off the ground (issue #152). The odd majors (21 /
+:: 23) are excluded by better-sqlite3 and vitest.
+:: Keep this in sync with "engines" in package.json.
+node -e "const v=process.versions.node.split('.').map(Number); process.exit((v[0]===22&&v[1]>=12)||v[0]>=24?0:1)"
+if errorlevel 1 (
+    call :error "Node.js %NODE_VER% is not supported. Use Node 22.12+ LTS or newer."
+    echo         Download: https://nodejs.org/  or  https://nodejs.cn/
     pause
     exit /b 1
 )
+
+:: Not fatal: setup now rebuilds the native modules for whatever ABI you run,
+:: so newer Node majors work - they are just slower to install.
+:: NOTE: keep every line inside these parenthesised blocks pure ASCII.
+:: cmd.exe mis-tracks its file offset when a block contains multi-byte UTF-8
+:: characters and starts eating the "echo " prefix of following lines.
+:: Bilingual guidance lives in the Node scripts, which print UTF-8 reliably.
+if %NODE_MAJOR% GTR %TESTED_NODE_MAJOR% (
+    echo [WARN] Node %NODE_VER% is newer than the tested LTS line, Node 22.
+    echo        Newer Node majors may have no prebuilt opus / better-sqlite3,
+    echo        so setup falls back to a source build - slower, needs C++ build tools.
+    echo        Recommended: Node 22 LTS - https://nodejs.org/ or https://nodejs.cn/
+    echo        This is only a warning; setup still builds the binaries for %NODE_VER%.
+    call :log "[WARN] Node major %NODE_MAJOR% is newer than tested LTS %TESTED_NODE_MAJOR%"
+)
 echo.
 
+:: Native addons are tied to one Node ABI. If node_modules was built by a
+:: different Node major, step 4b below detects it and repairs it.
+call :log "Node ABI for this install: see node_modules\.tsmusicbot-abi after step 4b"
+
 :: ============================================================
 :: Step 2: Check npm
 :: ============================================================
@@ -143,16 +173,40 @@ echo [OK] Backend dependencies installed.
 echo.
 
 :: ============================================================
-:: Step 4b: Download native binaries from CDN
+:: Step 4b: Verify / download / repair native binaries (ABI aware)
 :: ============================================================
-call :step "4b/7" "Downloading native binaries"
+call :step "4b/7" "Checking native binaries"
 
-node scripts/download-binaries.mjs %CDN_MIRROR% >>"%LOG_FILE%" 2>&1
-if errorlevel 1 (
-    echo [WARN] Binary download had issues. Check %LOG_FILE% for details.
-) else (
-    echo [OK] Native binaries installed.
+echo Verifying native modules for %NODE_VER% and downloading whatever is missing.
+echo Progress is shown below; the full transcript goes to the log file.
+echo.
+
+:: The .mjs writes progress to stderr and - with TSMB_BINARY_LOG_STDOUT=1 - the
+:: same lines to stdout. Redirecting only stdout therefore keeps the log complete
+:: while the user still sees live progress instead of a frozen window.
+set "TSMB_BINARY_LOG_STDOUT=1"
+node scripts\download-binaries.mjs %CDN_MIRROR% >>"%LOG_FILE%"
+set "BIN_RESULT=!errorlevel!"
+set "TSMB_BINARY_LOG_STDOUT="
+
+:: ASCII only inside these blocks - see the note near the Node version check.
+if not "!BIN_RESULT!"=="0" (
+    set "FAILED=1"
+    call :error "A required native module is unusable - see the [binary] lines above."
+    echo         Required: @discordjs/opus and better-sqlite3.
+    echo         Full log: %LOG_FILE%
 )
+
+if "!FAILED!"=="1" (
+    echo.
+    echo Setup aborted. Fix the problem above and run this script again.
+    call :log "Setup aborted at step 4b"
+    pause
+    exit /b 1
+)
+
+echo [OK] Native binaries ready for %NODE_VER%.
+echo      ABI recorded in node_modules\.tsmusicbot-abi
 echo.
 
 :: ============================================================

scripts/setup.sh

@@ -27,6 +27,28 @@ if ! command -v node &>/dev/null; then
 fi
 echo "[OK] Node.js $(node -v)"
 
+# Newest Node major this project is regularly tested against. Anything above
+# still works, it just may have no prebuilt addons and fall back to a source build.
+TESTED_NODE_MAJOR=22
+NODE_MAJOR="$(node -p 'process.versions.node.split(".")[0]')"
+
+# The floor is not just a major version, so let node decide. Node 20 was dropped:
+# better-sqlite3 ships no prebuilt binary for its ABI (115) since 12.10.0, so every
+# Node 20 install needed Python and a C++ toolchain just to get off the ground
+# (issue #152). The odd majors (21 / 23) are excluded by better-sqlite3 and vitest.
+# Keep in sync with package.json "engines".
+if ! node -e 'const v=process.versions.node.split(".").map(Number); process.exit((v[0]===22&&v[1]>=12)||v[0]>=24?0:1)'; then
+    echo "[ERROR] Node.js $(node -v) is not supported. Use Node 22.12+ LTS or newer."
+    echo "        https://nodejs.org/  |  https://nodejs.cn/"
+    exit 1
+fi
+if [ "$NODE_MAJOR" -gt "$TESTED_NODE_MAJOR" ]; then
+    echo "[WARN] Node $(node -v) is newer than the tested LTS line (Node 22)."
+    echo "       新版 Node 可能没有现成的 opus / better-sqlite3 预编译包,"
+    echo "       安装时会自动改用源码编译,需要 C/C++ 构建工具,速度较慢。"
+    echo "       This is only a warning - setup builds the binaries for $(node -v) either way."
+fi
+
 if ! command -v npm &>/dev/null; then
     echo "[ERROR] npm not found."
     exit 1
@@ -73,15 +95,30 @@ npm install --registry="$MIRROR_REGISTRY" --ignore-scripts 2>&1 | tee -a "$LOG_F
 echo "[OK] Dependencies installed."
 echo ""
 
-# ---- Step 2: Download native binaries from CDN ----
-echo "---- 2/5: Downloading native binaries ----"
+# ---- Step 2: Verify / download / repair native binaries (ABI aware) ----
+echo "---- 2/5: Checking native binaries ----"
 echo ""
 
-if node scripts/download-binaries.mjs $CDN_MIRROR 2>&1 | tee -a "$LOG_FILE"; then
-    echo "[OK] Native binaries installed."
-else
-    echo "[WARN] Some native binaries had issues (will try source build as fallback)."
+# The old `if node ... | tee ...` only printed a [WARN] and carried on, so a
+# broken native module still produced a "Setup Complete!" banner. It also read
+# the *pipeline's* status: `set -o pipefail` above happens to surface node's
+# failure, but a failing `tee` (unwritable log) was indistinguishable from a
+# failing node. PIPESTATUS[0] is exactly node's own exit code, nothing else.
+set +e
+node scripts/download-binaries.mjs $CDN_MIRROR 2>&1 | tee -a "$LOG_FILE"
+BIN_STATUS=${PIPESTATUS[0]}
+set -e
+
+if [ "$BIN_STATUS" -ne 0 ]; then
+    echo ""
+    echo "[ERROR] A required native module (@discordjs/opus / better-sqlite3) is unusable."
+    echo "        必需的原生模块不可用,安装中止。原因见上面的 [binary] 输出。"
+    echo "        Log: $LOG_FILE"
+    exit 1
 fi
+# ffmpeg-static failures are only a WARN inside the script above (a system
+# ffmpeg on PATH is a supported fallback), so reaching here means we are good.
+echo "[OK] Native binaries ready for $(node -v)."
 echo ""
 
 # ---- Step 3: Install web panel dependencies ----

scripts/smoke_issue51.sh

@@ -0,0 +1,96 @@
+#!/usr/bin/env bash
+# Smoke test for issue #51 — run AFTER you start the bot from temp/preview-merge
+# (or from main once both PRs are merged).
+#
+# Usage: ./scripts/smoke_issue51.sh [HOST]
+# Default HOST is http://127.0.0.1:3000
+
+set -e
+HOST="${1:-http://127.0.0.1:3000}"
+PASS=0
+FAIL=0
+note() { echo -e "\n=== $* ==="; }
+ok()   { echo "  [PASS] $*"; PASS=$((PASS+1)); }
+bad()  { echo "  [FAIL] $*"; FAIL=$((FAIL+1)); }
+
+# ---- Album search ----------------------------------------------------------
+note "1. /api/music/search/all returns {songs,albums,playlists}"
+
+RES=$(curl.exe -s "$HOST/api/music/search/all?q=%E5%91%A8%E6%9D%B0%E4%BC%A6") # 周杰伦
+KEYS=$(echo "$RES" | python3 -c "import json,sys;d=json.load(sys.stdin);print(','.join(sorted(d.keys())))")
+if [ "$KEYS" = "albums,playlists,songs" ]; then ok "keys = $KEYS"; else bad "keys = $KEYS (expected albums,playlists,songs)"; fi
+
+NA=$(echo "$RES" | python3 -c "import json,sys;d=json.load(sys.stdin);print(len(d.get('albums',[])))")
+NS=$(echo "$RES" | python3 -c "import json,sys;d=json.load(sys.stdin);print(len(d.get('songs',[])))")
+NP=$(echo "$RES" | python3 -c "import json,sys;d=json.load(sys.stdin);print(len(d.get('playlists',[])))")
+echo "  songs=$NS, albums=$NA, playlists=$NP"
+if [ "$NA" -gt 0 ]; then ok "albums populated"; else bad "albums empty (expected >0 for 周杰伦)"; fi
+if [ "$NS" -gt 0 ]; then ok "songs populated"; fi
+
+# ---- Album detail playback path -------------------------------------------
+note "2. /api/music/album/:id returns songs"
+
+if [ "$NA" -gt 0 ]; then
+  ALBUM_ID=$(echo "$RES" | python3 -c "import json,sys;d=json.load(sys.stdin);a=d['albums'][0];print(a['id'])")
+  PLATFORM=$(echo "$RES" | python3 -c "import json,sys;d=json.load(sys.stdin);a=d['albums'][0];print(a['platform'])")
+  echo "  testing album id=$ALBUM_ID platform=$PLATFORM"
+  ASONGS=$(curl.exe -s "$HOST/api/music/album/$ALBUM_ID?platform=$PLATFORM" | python3 -c "import json,sys;d=json.load(sys.stdin);print(len(d.get('songs',[])))" 2>/dev/null || echo 0)
+  if [ "$ASONGS" -gt 0 ]; then ok "album returned $ASONGS songs"; else bad "album endpoint returned 0 songs"; fi
+else
+  echo "  (skipped — no albums to test)"
+fi
+
+# ---- Avatar API ------------------------------------------------------------
+note "3. avatar GET 404 on bot with no avatar"
+
+BOT_ID=$(curl.exe -s "$HOST/api/bot" | python3 -c "import json,sys;d=json.load(sys.stdin);bots=d.get('bots',[]);print(bots[0]['id'] if bots else '')")
+if [ -z "$BOT_ID" ]; then bad "no bot found — create a bot first"; exit 1; fi
+echo "  using bot $BOT_ID"
+
+curl.exe -s -o /dev/null -w "%{http_code}" "$HOST/api/bot/$BOT_ID/avatar" > /tmp/code
+CODE=$(cat /tmp/code)
+if [ "$CODE" = "404" ] || [ "$CODE" = "200" ]; then ok "GET initial state = $CODE"; else bad "unexpected GET status $CODE"; fi
+
+note "4. avatar PUT 200 + GET 200 round-trip"
+# 1×1 transparent PNG (67 bytes)
+TINY_PNG_B64="iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNkYAAAAAYAAjCB0C8AAAAASUVORK5CYII="
+PUT_RES=$(curl.exe -s -X PUT "$HOST/api/bot/$BOT_ID/avatar" -H "Content-Type: application/json" \
+  -d "{\"dataUrl\":\"data:image/png;base64,$TINY_PNG_B64\"}")
+echo "  PUT response: $PUT_RES"
+GOT_PATH=$(echo "$PUT_RES" | python3 -c "import json,sys;d=json.load(sys.stdin);print(d.get('path',''))" 2>/dev/null || echo "")
+if [ "$GOT_PATH" = "$BOT_ID.png" ]; then ok "PUT returned path=$GOT_PATH"; else bad "PUT path = $GOT_PATH (expected $BOT_ID.png)"; fi
+
+curl.exe -s -o /tmp/avatar_check.png -w "%{http_code}" "$HOST/api/bot/$BOT_ID/avatar" > /tmp/code
+CODE=$(cat /tmp/code)
+SIZE=$(wc -c < /tmp/avatar_check.png)
+if [ "$CODE" = "200" ] && [ "$SIZE" -gt 60 ]; then ok "GET returned 200, $SIZE bytes"; else bad "GET status=$CODE size=$SIZE"; fi
+
+note "5. avatar DELETE 204 + GET 404"
+curl.exe -s -X DELETE "$HOST/api/bot/$BOT_ID/avatar" -o /dev/null -w "%{http_code}" > /tmp/code
+CODE=$(cat /tmp/code)
+if [ "$CODE" = "204" ]; then ok "DELETE returned 204"; else bad "DELETE status = $CODE"; fi
+
+curl.exe -s -o /dev/null -w "%{http_code}" "$HOST/api/bot/$BOT_ID/avatar" > /tmp/code
+CODE=$(cat /tmp/code)
+if [ "$CODE" = "404" ]; then ok "GET after DELETE returned 404"; else bad "GET after DELETE = $CODE"; fi
+
+note "6. avatar PUT rejects oversize (>200KB)"
+BIG_B64=$(node -e "console.log(Buffer.alloc(210*1024,7).toString('base64'))")
+curl.exe -s -o /dev/null -w "%{http_code}" -X PUT "$HOST/api/bot/$BOT_ID/avatar" \
+  -H "Content-Type: application/json" -d "{\"dataUrl\":\"data:image/png;base64,$BIG_B64\"}" > /tmp/code
+CODE=$(cat /tmp/code)
+if [ "$CODE" = "413" ]; then ok "oversize rejected with 413"; else bad "oversize status = $CODE (expected 413)"; fi
+
+note "7. avatar PUT rejects bad MIME (image/gif)"
+GIF_B64="R0lGODlhAQABAAAAACw="  # tiny gif
+curl.exe -s -o /dev/null -w "%{http_code}" -X PUT "$HOST/api/bot/$BOT_ID/avatar" \
+  -H "Content-Type: application/json" -d "{\"dataUrl\":\"data:image/gif;base64,$GIF_B64\"}" > /tmp/code
+CODE=$(cat /tmp/code)
+if [ "$CODE" = "400" ]; then ok "bad MIME rejected with 400"; else bad "bad MIME status = $CODE (expected 400)"; fi
+
+# ---------------------------------------------------------------------------
+echo ""
+echo "============================================="
+echo "SMOKE RESULT: $PASS passed, $FAIL failed"
+echo "============================================="
+[ "$FAIL" -eq 0 ]

scripts/start.bat

@@ -29,6 +29,19 @@ if not exist "dist" (
     exit /b 1
 )
 
+:: Preflight: do the compiled native modules match THIS Node version?
+:: Switching Node majors after setup leaves node_modules built for the old ABI;
+:: without this check the bot dies mid-startup with a NODE_MODULE_VERSION stack.
+:: check-native.mjs prints the bilingual explanation itself; keep the lines in
+:: this block pure ASCII (cmd.exe garbles multi-byte text inside blocks).
+node scripts\check-native.mjs
+if errorlevel 1 (
+    echo.
+    echo Please run scripts\setup.bat to rebuild the native modules.
+    pause
+    exit /b 1
+)
+
 :: Ensure PowerShell is in PATH (fix for jdymusic CDN playback on some systems)
 where powershell >nul 2>&1
 if errorlevel 1 (
@@ -38,7 +51,10 @@ if errorlevel 1 (
 )
 
 :: Start the application
+echo WebUI: http://localhost:3000
+echo Press Ctrl+C to stop.
+echo.
 node dist/index.js
 
 pause
-
+

src/audio/player.test.ts

@@ -1,8 +1,10 @@
-import { describe, it, expect } from "vitest";
+import { describe, it, expect, vi } from "vitest";
 import { mkdtempSync, writeFileSync, existsSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
-import { buildFfmpegArgs, shouldUsePowerShellDownload, cleanupTempDir, shouldEndOnStall, volumeToFactor } from "./player.js";
+import { Readable } from "node:stream";
+import { buildFfmpegArgs, shouldUsePowerShellDownload, cleanupTempDir, shouldEndOnStall, volumeToFactor, AudioPlayer } from "./player.js";
+import type { Logger } from "../logger.js";
 
 function getHeadersArg(args: string[]): string {
   const idx = args.indexOf("-headers");
@@ -53,13 +55,13 @@ describe("buildFfmpegArgs", () => {
     expect(idx).toBeLessThan(args.indexOf("-i")); // input options must precede -i
   });
 
-  it("inserts -ss before -i when seekSeconds > 0", () => {
+  it("inserts -ss after -i when seekSeconds > 0", () => {
     const args = buildFfmpegArgs("https://example.com/song.mp3", 42);
     const ssIdx = args.indexOf("-ss");
     const iIdx = args.indexOf("-i");
     expect(ssIdx).toBeGreaterThan(-1);
     expect(args[ssIdx + 1]).toBe("42");
-    expect(ssIdx).toBeLessThan(iIdx);
+    expect(ssIdx).toBeGreaterThan(iIdx);
   });
 
   it("does not insert -ss when seekSeconds is 0", () => {
@@ -200,3 +202,459 @@ describe("shouldEndOnStall (#89 mid-track stall watchdog)", () => {
     expect(shouldEndOnStall(10, false, MAX_EMPTY, MAX_STALL)).toBe(false);
   });
 });
+
+// Minimal stub: AudioPlayer only calls debug/info/warn/error; child() returns self.
+const silentLogger = {
+  debug() {},
+  info() {},
+  warn() {},
+  error() {},
+  fatal() {},
+  trace() {},
+  child() {
+    return silentLogger;
+  },
+} as unknown as Logger;
+
+function applyPlayerVolume(player: AudioPlayer, pcm: Buffer): Buffer {
+  return (
+    player as unknown as { applyVolume(input: Buffer): Buffer }
+  ).applyVolume(pcm);
+}
+
+function stereoPcm(sample: number, frames = 2): Buffer {
+  const pcm = Buffer.alloc(frames * 4);
+  for (let offset = 0; offset < pcm.length; offset += 2) {
+    pcm.writeInt16LE(sample, offset);
+  }
+  return pcm;
+}
+
+describe("AudioPlayer transient ducking gain", () => {
+  it("layers ducking on the PCM path without changing the user's base volume", () => {
+    const player = new AudioPlayer(silentLogger);
+    player.setVolume(100);
+    player.setDuckingGain(0.3);
+
+    const adjusted = applyPlayerVolume(player, stereoPcm(10_000));
+
+    expect(adjusted.readInt16LE(0)).toBe(3_000);
+    expect(adjusted.readInt16LE(2)).toBe(3_000);
+    expect(player.getVolume()).toBe(100);
+    expect(player.getDuckingGain()).toBe(0.3);
+  });
+
+  it("multiplies the transient gain by the existing base-volume curve", () => {
+    const player = new AudioPlayer(silentLogger);
+    player.setVolume(50);
+    player.setDuckingGain(0.5);
+
+    const adjusted = applyPlayerVolume(player, stereoPcm(10_000));
+    expect(adjusted.readInt16LE(0)).toBe(
+      Math.round(10_000 * volumeToFactor(50) * 0.5),
+    );
+  });
+
+  it("interpolates ramps smoothly across each stereo PCM frame", () => {
+    let now = 100;
+    const nowSpy = vi.spyOn(performance, "now").mockImplementation(() => now);
+    try {
+      const player = new AudioPlayer(silentLogger);
+      player.setVolume(100);
+      player.setDuckingGain(0.2, 100);
+
+      now = 150;
+      expect(player.getDuckingGain()).toBeCloseTo(0.6, 8);
+      const adjusted = applyPlayerVolume(player, stereoPcm(10_000));
+
+      // At t=150 the ramp is 0.6; at the end of this 20 ms frame it is 0.44.
+      expect(adjusted.readInt16LE(0)).toBe(6_000);
+      expect(adjusted.readInt16LE(2)).toBe(6_000);
+      expect(adjusted.readInt16LE(4)).toBe(4_400);
+      expect(adjusted.readInt16LE(6)).toBe(4_400);
+    } finally {
+      nowSpy.mockRestore();
+    }
+  });
+
+  it("clamps transient gain and ignores a non-finite update", () => {
+    const player = new AudioPlayer(silentLogger);
+    player.setDuckingGain(-1);
+    expect(player.getDuckingGain()).toBe(0);
+    player.setDuckingGain(2);
+    expect(player.getDuckingGain()).toBe(1);
+    player.setDuckingGain(Number.NaN);
+    expect(player.getDuckingGain()).toBe(1);
+  });
+});
+
+// A readable we fully control: no underlying source; we push PCM manually and
+// keep it open (never push(null)) to model the long-lived go-librespot sidecar.
+function openPcmReadable(): Readable {
+  return new Readable({ read() {} });
+}
+
+const wait = (ms: number): Promise<void> => new Promise<void>((r) => setTimeout(r, ms));
+const FRAME_BYTES = 3840; // PCM_FRAME_BYTES: 960 samples * 2ch * 2 bytes @48k s16le
+
+describe("AudioPlayer external-PCM mode (playPcmStream)", () => {
+  it("emits Opus 'frame' events from the external PCM stream without spawning ffmpeg", async () => {
+    const player = new AudioPlayer(silentLogger);
+    const frames: Buffer[] = [];
+    player.on("frame", (f) => frames.push(f));
+
+    const stream = openPcmReadable();
+    player.playPcmStream(stream, {});
+    stream.push(Buffer.alloc(FRAME_BYTES * 10)); // ~10 frames of PCM
+
+    await wait(150); // ~7 frame ticks at 20ms
+
+    expect(player.getState()).toBe("playing");
+    expect(frames.length).toBeGreaterThan(0);
+    expect(Buffer.isBuffer(frames[0])).toBe(true);
+    player.stop();
+  });
+
+  it("does NOT emit 'trackEnd' on underrun while external (stream stays open)", async () => {
+    const player = new AudioPlayer(silentLogger);
+    let ended = 0;
+    const frames: Buffer[] = [];
+    player.on("trackEnd", () => ended++);
+    player.on("frame", (f) => frames.push(f));
+
+    const stream = openPcmReadable();
+    player.playPcmStream(stream, {});
+    stream.push(Buffer.alloc(FRAME_BYTES * 2)); // only 2 frames, then underrun
+
+    await wait(200); // long after those 2 frames have drained
+
+    // In the url path, ffmpeg===null + empty buffer would fire trackEnd; here it must not.
+    expect(ended).toBe(0);
+    // Silence frames keep the 20ms timeline alive -> more than the 2 fed frames emitted.
+    expect(frames.length).toBeGreaterThan(2);
+    expect(player.getState()).toBe("playing");
+    player.stop();
+  });
+
+  // CORRECTION C2 (c): stop() DETACHES the shared readable — it must NOT be destroyed
+  // (destroying the sidecar's long-lived ffmpeg stdout would kill it for every future
+  // track). The sessionId bump + listener removal fence stale PCM out of pcmBuffer.
+  it("stop() detaches external mode without destroying the readable, and fences via sessionId", async () => {
+    const player = new AudioPlayer(silentLogger);
+    const frames: Buffer[] = [];
+    player.on("frame", (f) => frames.push(f));
+
+    const stream = openPcmReadable();
+    player.playPcmStream(stream, {});
+    expect(stream.listenerCount("data")).toBe(1);
+    stream.push(Buffer.alloc(FRAME_BYTES * 5));
+    await wait(80);
+
+    player.stop();
+    expect(player.getState()).toBe("idle");
+    // C2: the shared sidecar stream must NOT be destroyed by teardown.
+    expect(stream.destroyed).toBe(false);
+    // Player's listeners are removed on detach (data/end/error).
+    expect(stream.listenerCount("data")).toBe(0);
+    expect(stream.listenerCount("end")).toBe(0);
+    expect(stream.listenerCount("error")).toBe(0);
+
+    const countAtStop = frames.length;
+    // sessionId fence + detached listeners: PCM pushed after stop must not
+    // resurrect the timeline or re-feed pcmBuffer.
+    stream.push(Buffer.alloc(FRAME_BYTES * 5));
+    await wait(80);
+    expect(frames.length).toBe(countAtStop);
+  });
+
+  // CORRECTION C2 (a): a gapless track change is driven by the sidecar pushing LATER
+  // PCM over the SAME already-attached stream. The player must NOT detach/re-attach
+  // (no second playPcmStream) — one persistent data listener serves every track.
+  it("(C2-a) feeds a later chunk over the SAME single attachment — gapless track change, no re-attach", async () => {
+    const player = new AudioPlayer(silentLogger);
+    const frames: Buffer[] = [];
+    player.on("frame", (f) => frames.push(f));
+
+    const stream = openPcmReadable();
+    player.playPcmStream(stream, {});
+    expect(stream.listenerCount("data")).toBe(1); // attached exactly once
+
+    stream.push(Buffer.alloc(FRAME_BYTES * 4)); // "track 1" PCM
+    await wait(120);
+    const afterFirst = frames.length;
+    expect(afterFirst).toBeGreaterThan(0);
+
+    stream.push(Buffer.alloc(FRAME_BYTES * 4)); // sidecar seamlessly rolls into "track 2"
+    await wait(120);
+    expect(frames.length).toBeGreaterThan(afterFirst);
+
+    // Still exactly ONE listener — no detach/re-attach across the handoff.
+    expect(stream.listenerCount("data")).toBe(1);
+    expect(player.getState()).toBe("playing");
+    player.stop();
+  });
+
+  // CORRECTION C2 (b): a second playPcmStream detaches the first (NOT destroyed, and it
+  // stops feeding pcmBuffer) and attaches the second.
+  it("(C2-b) a second playPcmStream detaches the first (not destroyed, stops feeding) and attaches the second", async () => {
+    const player = new AudioPlayer(silentLogger);
+    const frames: Buffer[] = [];
+    player.on("frame", (f) => frames.push(f));
+
+    const first = openPcmReadable();
+    player.playPcmStream(first, {});
+    first.push(Buffer.alloc(FRAME_BYTES * 4));
+    await wait(120);
+    expect(frames.length).toBeGreaterThan(0);
+    expect(first.listenerCount("data")).toBe(1);
+
+    const second = openPcmReadable();
+    player.playPcmStream(second, {}); // fences + detaches `first`, attaches `second`
+
+    // C2: `first` is DETACHED, not destroyed.
+    expect(first.destroyed).toBe(false);
+    // `first` no longer feeds pcmBuffer — its data listener was removed.
+    expect(first.listenerCount("data")).toBe(0);
+    // `second` is now the attached source.
+    expect(second.listenerCount("data")).toBe(1);
+    expect(player.getState()).toBe("playing");
+    player.stop();
+  });
+
+  it("fires onExternalEnd when the readable ends (drives controller-based advance)", async () => {
+    const player = new AudioPlayer(silentLogger);
+    let endedCb = 0;
+
+    const stream = openPcmReadable();
+    player.playPcmStream(stream, { onExternalEnd: () => endedCb++ });
+    stream.push(Buffer.alloc(FRAME_BYTES));
+    await wait(40);
+    stream.push(null); // end-of-stream
+    await wait(40);
+
+    expect(endedCb).toBe(1);
+    player.stop();
+  });
+
+  it("seek() is a local no-op in external mode (never respawns ffmpeg on a spotify sentinel)", async () => {
+    const player = new AudioPlayer(silentLogger);
+    const stream = openPcmReadable();
+    player.playPcmStream(stream, {});
+    stream.push(Buffer.alloc(FRAME_BYTES * 3));
+    await wait(40);
+
+    expect(() => player.seek(30)).not.toThrow();
+    // Still external, still playing — no url-ffmpeg respawn, state unchanged.
+    expect(player.getState()).toBe("playing");
+    player.stop();
+  });
+
+  it("isExternalActive() is false initially, true after playPcmStream, false after stop()", () => {
+    const player = new AudioPlayer(silentLogger);
+    // Idle: never attached.
+    expect(player.isExternalActive()).toBe(false);
+
+    const stream = openPcmReadable();
+    player.playPcmStream(stream, {});
+    // Attached to the external sidecar stream.
+    expect(player.isExternalActive()).toBe(true);
+
+    player.stop();
+    // Detached again — the orchestrator uses this to know it must re-attach.
+    expect(player.isExternalActive()).toBe(false);
+  });
+
+  it("pause()/resume() still gate local emission in external mode (unchanged semantics)", async () => {
+    const player = new AudioPlayer(silentLogger);
+    const stream = openPcmReadable();
+    player.playPcmStream(stream, {});
+    stream.push(Buffer.alloc(FRAME_BYTES * 3));
+    await wait(40);
+
+    player.pause();
+    expect(player.getState()).toBe("paused");
+    player.resume();
+    expect(player.getState()).toBe("playing");
+    player.stop();
+  });
+
+  // CORRECTION C1 (whole-branch): mixed queue [spotifyA, neteaseB, spotifyC].
+  // Advancing A -> B (a NON-spotify track) calls stop(), whose detachExternalStream()
+  // PAUSES the backend's long-lived SHARED readable (state.flowing = false). When the
+  // LATER spotify track C reuses the SAME backend, the orchestrator re-attaches that
+  // SAME readable via playPcmStream(). Node's Readable.on('data') only auto-resumes
+  // when flowing !== false, so without an explicit resume() the shared stream stays
+  // paused, onData never fires, pcmBuffer stays empty, and C plays only silence frames.
+  // Regression: after re-attach the shared stream MUST be flowing again and real PCM
+  // MUST reach the player.
+  it("(C1) resumes a re-attached, previously-paused SHARED stream so a later Spotify track isn't silent", async () => {
+    const player = new AudioPlayer(silentLogger);
+    const frames: Buffer[] = [];
+    player.on("frame", (f) => frames.push(f));
+
+    // The backend's long-lived, SHARED readable, reused across every track.
+    const shared = openPcmReadable();
+
+    // --- Spotify track A: first attach (auto-resumes, flowing was null !== false).
+    player.playPcmStream(shared, {});
+    shared.push(Buffer.alloc(FRAME_BYTES * 4));
+    await wait(120);
+    expect(frames.length).toBeGreaterThan(0);
+
+    // --- Advance to a NON-spotify track (neteaseB): play(url) begins with stop(),
+    // which detaches AND pauses the shared stream (state.flowing = false).
+    player.stop();
+    expect(shared.isPaused()).toBe(true); // shared stream is now paused
+    expect(player.getState()).toBe("idle");
+
+    // --- Spotify track C reuses the SAME backend: isExternalActive() is false so the
+    // orchestrator re-attaches the SAME (paused) shared readable.
+    expect(player.isExternalActive()).toBe(false);
+
+    // Spy on the shared stream to observe whether real PCM actually flows to the
+    // player. Adding a 'data' listener while flowing===false does NOT resume it
+    // (Node semantics), so this spy cannot mask the bug — pre-fix it stays at 0.
+    let spyBytes = 0;
+    shared.on("data", (c: Buffer) => {
+      spyBytes += c.length;
+    });
+
+    player.playPcmStream(shared, {}); // re-attach the SAME shared readable
+
+    // The re-attached stream must be flowing again, or track C is silent.
+    expect(shared.isPaused()).toBe(false);
+
+    shared.push(Buffer.alloc(FRAME_BYTES * 4)); // "track C" PCM
+    await wait(120);
+
+    // onData must have run (real PCM reached the player), not just silence frames.
+    expect(spyBytes).toBeGreaterThan(0);
+    expect(player.getState()).toBe("playing");
+    player.stop();
+  });
+});
+
+// R3-4: the 20ms frame loop keeps running while paused (so a live-but-silent
+// stream can refill on resume). But the stall/EOF end-detection branches MUST
+// only run while state==="playing" — otherwise pausing a stalled or
+// unknown-duration stream still accumulates emptyFrameAttempts and auto-emits
+// trackEnd (~5s later), making the controller skip the paused track.
+//
+// These tests drive the real url-path frame loop (this.ffmpeg !== null, NOT
+// external mode), which cannot be exercised via playPcmStream (that sets
+// externalMode and suppresses both branches). We inject a fake live ffmpeg +
+// an empty pcmBuffer (a stream that stays alive but never yields a full PCM
+// frame) and run the actual startFrameLoop() under fake timers. `performance`
+// is faked in lockstep with the timer clock so each tick advances a real 20ms,
+// letting us cheaply cross MAX_EMPTY_ATTEMPTS (250 ticks ≈ 5s) deterministically.
+describe("AudioPlayer stall/EOF end-detection is gated on playing state (R3-4)", () => {
+  // Fake `performance` in lockstep with the timer clock so each advanced 20ms is
+  // a real frame tick (the loop computes its delay from performance.now()).
+  const FAKE_TIMER_OPTS: Parameters<typeof vi.useFakeTimers>[0] = {
+    toFake: ["setTimeout", "clearTimeout", "setInterval", "clearInterval", "Date", "performance"],
+  };
+
+  // A player primed as "playing" with a LIVE ffmpeg that never produces a full
+  // PCM frame (unknown duration -> isNearEnd forced true). startFrameLoop() runs
+  // the genuine loop; no real process is spawned (fake ffmpeg has no pid, so the
+  // end path never touches forceCleanup/process.kill).
+  function makeStalledPlaying(): AudioPlayer {
+    const player = new AudioPlayer(silentLogger);
+    const p = player as unknown as {
+      ffmpeg: unknown;
+      currentSongDuration: number;
+      pcmBuffer: Buffer;
+      emptyFrameAttempts: number;
+      framesPlayed: number;
+      state: string;
+      startFrameLoop(): void;
+    };
+    p.ffmpeg = { pid: undefined }; // live ffmpeg, but delivers no PCM
+    p.currentSongDuration = 0; // unknown duration -> isNearEnd === true
+    p.pcmBuffer = Buffer.alloc(0); // always < one PCM frame
+    p.emptyFrameAttempts = 0;
+    p.framesPlayed = 0;
+    p.state = "playing";
+    p.startFrameLoop();
+    return player;
+  }
+
+  it("does NOT emit trackEnd (and stays paused) when a stalled unknown-duration stream is paused past the stall threshold", () => {
+    vi.useFakeTimers(FAKE_TIMER_OPTS);
+    try {
+      const player = makeStalledPlaying();
+      let ended = 0;
+      player.on("trackEnd", () => ended++);
+
+      player.pause();
+      expect(player.getState()).toBe("paused");
+
+      // Advance well past MAX_EMPTY_ATTEMPTS (250 ticks ≈ 5s): ~300 ticks.
+      vi.advanceTimersByTime(20 * 300);
+
+      expect(ended).toBe(0);
+      expect(player.getState()).toBe("paused");
+      player.stop();
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+
+  it("STILL emits trackEnd when the SAME stalled unknown-duration stream is left playing (dead-stream recovery #89 preserved)", () => {
+    vi.useFakeTimers(FAKE_TIMER_OPTS);
+    try {
+      const player = makeStalledPlaying(); // stays "playing"
+      let ended = 0;
+      player.on("trackEnd", () => ended++);
+
+      vi.advanceTimersByTime(20 * 300); // cross the 250-tick stall threshold
+
+      expect(ended).toBe(1);
+      expect(player.getState()).toBe("idle");
+      player.stop();
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+
+  it("does not spuriously end after a brief pause+resume on a healthy stream", () => {
+    vi.useFakeTimers(FAKE_TIMER_OPTS);
+    try {
+      const player = new AudioPlayer(silentLogger);
+      const p = player as unknown as {
+        ffmpeg: unknown;
+        currentSongDuration: number;
+        pcmBuffer: Buffer;
+        emptyFrameAttempts: number;
+        framesPlayed: number;
+        state: string;
+        startFrameLoop(): void;
+      };
+      // Healthy: a live ffmpeg with a large buffered runway that never drains
+      // empty across the ticks below, so no underrun is ever seen.
+      p.ffmpeg = { pid: undefined };
+      p.currentSongDuration = 0;
+      p.pcmBuffer = Buffer.alloc(FRAME_BYTES * 400);
+      p.emptyFrameAttempts = 0;
+      p.framesPlayed = 0;
+      p.state = "playing";
+      p.startFrameLoop();
+
+      let ended = 0;
+      player.on("trackEnd", () => ended++);
+
+      vi.advanceTimersByTime(20 * 5); // play a few frames
+      player.pause();
+      vi.advanceTimersByTime(20 * 100); // brief pause (buffer NOT drained while paused)
+      player.resume();
+      expect(player.getState()).toBe("playing");
+      vi.advanceTimersByTime(20 * 100); // resume; still plenty of runway
+
+      expect(ended).toBe(0);
+      expect(player.getState()).toBe("playing");
+      player.stop();
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+});

src/audio/player.ts

@@ -5,6 +5,7 @@ import { accessSync, chmodSync, constants, mkdtempSync, rmSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { createOpusEncoder, PCM_FRAME_BYTES, type Encoder } from "./encoder.js";
+import type { Readable } from "node:stream";
 import type { Logger } from "../logger.js";
 
 const require = createRequire(import.meta.url);
@@ -47,7 +48,7 @@ const resolvedFfmpeg: string = (() => {
   return "ffmpeg";
 })();
 
-function getFfmpegCommand(): string {
+export function getFfmpegCommand(): string {
   return resolvedFfmpeg;
 }
 
@@ -102,8 +103,10 @@ export function buildFfmpegArgs(url: string, seekSeconds: number): string[] {
       "-reconnect_on_http_error", "4xx,5xx",
     );
   }
+  args.push("-i", url);
+  // Output-side seek (after -i): works on CDNs that reject Range/keyframe seeks (NetEase music.126.net).
   if (seekSeconds > 0) args.push("-ss", String(seekSeconds));
-  args.push("-i", url, "-f", "s16le", "-ar", "48000", "-ac", "2", "-acodec", "pcm_s16le", "-");
+  args.push("-f", "s16le", "-ar", "48000", "-ac", "2", "-acodec", "pcm_s16le", "-");
 
   return args;
 }
@@ -160,6 +163,15 @@ export class AudioPlayer extends EventEmitter {
   private encoder: Encoder;
   private state: PlayerState = "idle";
   private volume = 75;
+  /**
+   * A transient gain envelope layered on top of the persisted user volume.
+   * Voice ducking drives this value; keeping it separate means a temporary
+   * attenuation can never leak into the saved volume setting.
+   */
+  private duckingRampStartGain = 1;
+  private duckingTargetGain = 1;
+  private duckingRampStartedAt = 0;
+  private duckingRampDurationMs = 0;
   private pcmBuffer: Buffer = Buffer.alloc(0);
   private logger: Logger;
   private frameLoopRunning = false;
@@ -187,6 +199,22 @@ export class AudioPlayer extends EventEmitter {
   private static readonly MAX_STALL_ATTEMPTS = 3000;
   private currentSongDuration = 0; // 当前歌曲总时长（秒）
 
+  // --- External PCM mode (Stage 2: go-librespot Spotify sidecar) ---
+  // When true, PCM arrives from a long-lived external Readable instead of a
+  // per-URL ffmpeg: this.ffmpeg stays null, and the underrun-driven trackEnd
+  // branches are suppressed (advance is driven by the controller, not EOF).
+  //
+  // CORRECTION C2: externalStream is the backend's LONG-LIVED, SHARED ffmpeg
+  // stdout (one stream reused across every track). Teardown must DETACH (remove
+  // the listeners we added + pause), never destroy it. We keep references to the
+  // exact handler functions so detach can removeListener precisely.
+  private externalMode = false;
+  private externalStream: Readable | null = null;
+  private onExternalEnd: (() => void) | null = null;
+  private externalDataHandler: ((chunk: Buffer) => void) | null = null;
+  private externalEndHandler: (() => void) | null = null;
+  private externalErrorHandler: ((err: Error) => void) | null = null;
+
   constructor(logger: Logger) {
     super();
     this.encoder = createOpusEncoder();
@@ -390,6 +418,117 @@ export class AudioPlayer extends EventEmitter {
     this.startFrameLoop();
   }
 
+  /**
+   * External-PCM mode (Stage 2 go-librespot Spotify sidecar).
+   *
+   * Feeds an already-normalized 48kHz/s16le/stereo PCM Readable (the
+   * go-librespot FIFO -> ffmpeg output) straight into the existing pcmBuffer +
+   * 20ms frame loop + Opus encoder + "frame" emission, WITHOUT spawning a
+   * per-URL ffmpeg. The url play() path is left completely untouched.
+   *
+   * Track advance is NOT driven by buffer underrun here (the sidecar stream is
+   * continuous and never EOFs per song); the caller drives advance via the
+   * SpotifyController "trackEnded" WebSocket event. onExternalEnd fires only if
+   * the underlying readable itself ends or errors.
+   *
+   * CORRECTION C2: the readable is the backend's long-lived, SHARED ffmpeg
+   * stdout reused across every track — a gapless track change is just LATER PCM
+   * on this SAME already-attached stream (no re-attach). Teardown DETACHES
+   * (removes our listeners + pauses); it never destroys the shared stream.
+   */
+  playPcmStream(readable: Readable, opts: { onExternalEnd?: () => void } = {}): void {
+    // 1. Fence current playback: stop() bumps sessionId, clears pcmBuffer, kills
+    //    any ffmpeg, and DETACHES (never destroys) any prior external stream.
+    this.stop();
+
+    const currentSessionId = this.sessionId;
+    this.externalMode = true;
+    this.externalStream = readable;
+    this.onExternalEnd = opts.onExternalEnd ?? null;
+    // Leave this.ffmpeg = null; clear currentUrl so seek() cannot respawn ffmpeg.
+    this.currentUrl = "";
+    this.seekOffset = 0;
+    this.framesPlayed = 0;
+    this.healthyFrames = 0;
+    this.ffmpegPaused = false;
+    this.spawnFailed = false;
+    this.emptyFrameAttempts = 0;
+    this.currentSongDuration = 0;
+
+    // Same ingestion + high-water backpressure as the ffmpeg.stdout handler,
+    // but pausing the Readable instead of ffmpeg.stdout. sessionId-guarded so
+    // stale sidecar PCM can't leak into a new track after stop()/skip. Handler
+    // refs are stored so detach can remove exactly these listeners (C2).
+    const onData = (chunk: Buffer): void => {
+      if (this.sessionId !== currentSessionId) return;
+      this.pcmBuffer = Buffer.concat([this.pcmBuffer, chunk]);
+      if (
+        this.pcmBuffer.length > AudioPlayer.BUFFER_HIGH_WATER &&
+        !this.ffmpegPaused &&
+        this.externalStream === readable
+      ) {
+        readable.pause();
+        this.ffmpegPaused = true;
+      }
+    };
+    const onEnd = (): void => {
+      if (this.sessionId !== currentSessionId) return;
+      this.onExternalEnd?.();
+    };
+    const onError = (err: Error): void => {
+      if (this.sessionId !== currentSessionId) return;
+      this.logger.warn({ err }, "External PCM stream error");
+      this.onExternalEnd?.();
+    };
+
+    this.externalDataHandler = onData;
+    this.externalEndHandler = onEnd;
+    this.externalErrorHandler = onError;
+
+    readable.on("data", onData);
+    readable.on("end", onEnd);
+    readable.on("error", onError);
+
+    // CORRECTION C1: explicitly resume a re-attached, previously-paused Readable.
+    // The backend's SHARED stdout is reused across every track; a prior non-spotify
+    // advance ran stop() -> detachExternalStream() which pause()d it (state.flowing =
+    // false). Node's Readable.on('data') only auto-resumes when flowing !== false, so
+    // re-attaching a paused stream would leave it stuck: onData never fires, pcmBuffer
+    // stays empty, and a later Spotify track plays only silence. resume() is safe/
+    // idempotent on a first attach (never-paused/already-flowing) stream.
+    readable.resume();
+
+    this.state = "playing";
+    this.startFrameLoop();
+  }
+
+  /**
+   * CORRECTION C2: DETACH, never destroy. The external readable is the backend's
+   * long-lived, SHARED ffmpeg stdout reused across every track; destroying it
+   * would kill the sidecar pipe for all future tracks. Remove only the listeners
+   * WE added and pause the flow so stale PCM stops landing in pcmBuffer, then
+   * clear the external-mode state.
+   */
+  private detachExternalStream(): void {
+    const stream = this.externalStream;
+    if (stream) {
+      if (this.externalDataHandler) stream.off("data", this.externalDataHandler);
+      if (this.externalEndHandler) stream.off("end", this.externalEndHandler);
+      if (this.externalErrorHandler) stream.off("error", this.externalErrorHandler);
+      try {
+        stream.pause();
+      } catch {
+        /* best-effort: never destroy the shared sidecar stream */
+      }
+    }
+    this.externalDataHandler = null;
+    this.externalEndHandler = null;
+    this.externalErrorHandler = null;
+    this.externalStream = null;
+    this.externalMode = false;
+    this.onExternalEnd = null;
+  }
+
   stop(): void {
     // 3. 递增 ID 是最有效的逻辑“隔离墙”
     this.sessionId++; 
@@ -419,6 +558,11 @@ export class AudioPlayer extends EventEmitter {
       this.currentTempDir = null;
     }
 
+    // CORRECTION C2: tear down external mode by DETACHING (remove our listeners +
+    // pause) — never destroy the shared, long-lived sidecar stream. The
+    // sessionId++ above already fences the external data/end/error handlers.
+    this.detachExternalStream();
+
     this.ffmpegPaused = false;
     this.spawnFailed = false;
     this.state = "idle";
@@ -480,7 +624,17 @@ export class AudioPlayer extends EventEmitter {
         ? (this.currentSongDuration - elapsed) <= 5 // 距离结尾不足5秒
         : true; // 未知时长时保守处理
       
-      if (this.ffmpeg !== null && this.pcmBuffer.length < PCM_FRAME_BYTES) {
+      // External mode: the sidecar PCM stream is continuous and never EOFs per
+      // song; a transient underrun must NOT end the track (advance is driven by
+      // the controller). Skip BOTH drain/stall branches while externalMode.
+      //
+      // R3-4: gate BOTH end-detection branches on state==="playing". While paused
+      // the loop still ticks (so a resumed stream can refill), but it must NOT
+      // accumulate stall attempts or emit trackEnd — otherwise pausing a stalled/
+      // unknown-duration stream would auto-advance ~5s later. Because the if is
+      // now false while paused, the else resets emptyFrameAttempts to 0, so a
+      // resumed healthy stream starts fresh and never ends instantly.
+      if (this.state === "playing" && !this.externalMode && this.ffmpeg !== null && this.pcmBuffer.length < PCM_FRAME_BYTES) {
         this.emptyFrameAttempts++;
         
         // End the track when FFmpeg has gone silent: quickly if we're near the
@@ -505,20 +659,20 @@ export class AudioPlayer extends EventEmitter {
             nearEnd: isNearEnd,
           }, "FFmpeg stopped outputting data, ending track");
           this.frameLoopRunning = false;
-          if (this.state !== "idle") {
-            this.state = "idle";
-            // 清理FFmpeg进程
-            if (this.ffmpeg) {
-              const procToKill = this.ffmpeg;
-              const pidToKill = procToKill.pid;
-              this.ffmpeg = null;
-              if (pidToKill) {
-                this.forceCleanup(procToKill, pidToKill);
-              }
+          // The outer gate guarantees state==="playing" here, so no !=="idle"
+          // guard is needed: end the track directly.
+          this.state = "idle";
+          // 清理FFmpeg进程
+          if (this.ffmpeg) {
+            const procToKill = this.ffmpeg;
+            const pidToKill = procToKill.pid;
+            this.ffmpeg = null;
+            if (pidToKill) {
+              this.forceCleanup(procToKill, pidToKill);
             }
-            this.consecutiveFailures = 0;
-            this.emit("trackEnd");
           }
+          this.consecutiveFailures = 0;
+          this.emit("trackEnd");
           return;
         }
       } else {
@@ -526,14 +680,15 @@ export class AudioPlayer extends EventEmitter {
         this.emptyFrameAttempts = 0;
       }
 
-      if (!this.ffmpeg && this.pcmBuffer.length < PCM_FRAME_BYTES) {
+      // R3-4: likewise gated on state==="playing" — a drained/EOF'd stream must
+      // not emit trackEnd while paused; end-detection resumes on resume().
+      if (this.state === "playing" && !this.externalMode && !this.ffmpeg && this.pcmBuffer.length < PCM_FRAME_BYTES) {
         this.frameLoopRunning = false;
-        if (this.state !== "idle") {
-          this.state = "idle";
-          if (!this.spawnFailed) {
-            this.consecutiveFailures = 0;
-            this.emit("trackEnd");
-          }
+        // Outer gate guarantees state==="playing"; end directly (no !=="idle" guard).
+        this.state = "idle";
+        if (!this.spawnFailed) {
+          this.consecutiveFailures = 0;
+          this.emit("trackEnd");
         }
         return;
       }
@@ -542,13 +697,24 @@ export class AudioPlayer extends EventEmitter {
   }
 
   private sendNextFrame(): void {
-    if (this.pcmBuffer.length < PCM_FRAME_BYTES) return;
+    if (this.pcmBuffer.length < PCM_FRAME_BYTES) {
+      // External mode: the sidecar PCM stream is long-lived and must NOT end on
+      // a transient underrun. Emit an encoded silence frame so the 20ms voice
+      // timeline stays continuous instead of returning (which would desync TS).
+      if (this.externalMode) this.emitSilenceFrame();
+      return;
+    }
     const pcmFrame = this.pcmBuffer.subarray(0, PCM_FRAME_BYTES);
     this.pcmBuffer = this.pcmBuffer.subarray(PCM_FRAME_BYTES);
 
-    if (this.ffmpegPaused && this.pcmBuffer.length < AudioPlayer.BUFFER_LOW_WATER && this.ffmpeg?.stdout) {
-      this.ffmpeg.stdout.resume();
-      this.ffmpegPaused = false;
+    if (this.ffmpegPaused && this.pcmBuffer.length < AudioPlayer.BUFFER_LOW_WATER) {
+      if (this.externalMode && this.externalStream) {
+        this.externalStream.resume();
+        this.ffmpegPaused = false;
+      } else if (this.ffmpeg?.stdout) {
+        this.ffmpeg.stdout.resume();
+        this.ffmpegPaused = false;
+      }
     }
 
     try {
@@ -566,20 +732,75 @@ export class AudioPlayer extends EventEmitter {
     }
   }
 
+  private emitSilenceFrame(): void {
+    try {
+      const opusFrame = this.encoder.encode(Buffer.alloc(PCM_FRAME_BYTES));
+      this.emit("frame", opusFrame);
+      this.framesPlayed++;
+    } catch (err) {
+      this.emit("error", err as Error);
+    }
+  }
+
   private applyVolume(pcm: Buffer): Buffer {
-    const factor = volumeToFactor(this.volume);
-    // factor === 1 only at volume 100; skip the per-sample loop at full loudness.
-    if (factor >= 1) return Buffer.from(pcm);
+    const baseFactor = volumeToFactor(this.volume);
+    const now = performance.now();
+    const startDuckingGain = this.duckingGainAt(now);
+    const endDuckingGain = this.duckingGainAt(now + FRAME_DURATION_MS);
+    const startFactor = baseFactor * startDuckingGain;
+    const endFactor = baseFactor * endDuckingGain;
+
+    if (startFactor >= 1 && endFactor >= 1) {
+      return Buffer.from(pcm);
+    }
+
     const out = Buffer.alloc(pcm.length);
+    // Most frames are outside the short attack/release windows. Preserve the
+    // old constant-factor hot path instead of doing interpolation per sample.
+    if (startFactor === endFactor) {
+      for (let i = 0; i < pcm.length; i += 2) {
+        const sample = Math.round(pcm.readInt16LE(i) * startFactor);
+        out.writeInt16LE(Math.max(-32768, Math.min(32767, sample)), i);
+      }
+      return out;
+    }
+
+    // PCM is fixed at stereo s16le. Use one gain for each L/R pair so a ramp
+    // never creates a tiny channel imbalance, and span the whole 20 ms frame.
+    const stereoFrames = Math.max(1, Math.ceil(pcm.length / 4));
     for (let i = 0; i < pcm.length; i += 2) {
-      let sample = Math.round(pcm.readInt16LE(i) * factor);
+      const frameIndex = Math.floor(i / 4);
+      const progress = stereoFrames === 1 ? 0 : frameIndex / (stereoFrames - 1);
+      const factor = startFactor + (endFactor - startFactor) * progress;
+      const sample = Math.round(pcm.readInt16LE(i) * factor);
       out.writeInt16LE(Math.max(-32768, Math.min(32767, sample)), i);
     }
     return out;
   }
 
+  private duckingGainAt(at: number): number {
+    if (this.duckingRampDurationMs <= 0) return this.duckingTargetGain;
+
+    const progress = Math.max(
+      0,
+      Math.min(1, (at - this.duckingRampStartedAt) / this.duckingRampDurationMs),
+    );
+    return (
+      this.duckingRampStartGain +
+      (this.duckingTargetGain - this.duckingRampStartGain) * progress
+    );
+  }
+
+  // NOTE: in external (Spotify sidecar) mode getElapsed() is frame-count based
+  // (framesPlayed includes silence frames emitted on underrun) and therefore
+  // only APPROXIMATE — the authoritative position is the controller's live
+  // status.track.position. This approximation is acceptable for Spotify.
   getElapsed(): number { return this.seekOffset + (this.framesPlayed * FRAME_DURATION_MS) / 1000; }
-  seek(seconds: number): void { 
+  seek(seconds: number): void {
+    // External (Spotify sidecar) mode: local seek is a no-op. Respawning ffmpeg
+    // on the spotify: sentinel would collide with the continuous PCM source;
+    // transport is delegated to the SpotifyController by the caller (Task 7).
+    if (this.externalMode) return;
     if (this.currentUrl && Number.isFinite(seconds) && seconds >= 0) {
       this.play(this.currentUrl, seconds, this.currentSongDuration);
     }
@@ -589,5 +810,25 @@ export class AudioPlayer extends EventEmitter {
   resetFailures(): void { this.consecutiveFailures = 0; }
   setVolume(vol: number): void { this.volume = Math.max(0, Math.min(100, vol)); }
   getVolume(): number { return this.volume; }
+  /** Set the temporary voice-ducking gain (0=silent, 1=unchanged). */
+  setDuckingGain(gain: number, rampMs = 0): void {
+    if (!Number.isFinite(gain)) return;
+
+    const now = performance.now();
+    const currentGain = this.duckingGainAt(now);
+    const targetGain = Math.max(0, Math.min(1, gain));
+    const duration = Number.isFinite(rampMs) ? Math.max(0, rampMs) : 0;
+
+    this.duckingRampStartGain = currentGain;
+    this.duckingTargetGain = targetGain;
+    this.duckingRampStartedAt = now;
+    this.duckingRampDurationMs =
+      duration > 0 && currentGain !== targetGain ? duration : 0;
+  }
+  getDuckingGain(): number { return this.duckingGainAt(performance.now()); }
   getState(): PlayerState { return this.state; }
-}
+  // True only while attached to an external (Spotify sidecar) PCM stream. Used
+  // by the orchestrator to decide whether to re-attach: stop() detaches (sets
+  // externalMode=false) so this is false after any player.stop().
+  isExternalActive(): boolean { return this.externalMode; }
+}

src/audio/queue.test.ts

@@ -564,4 +564,182 @@ describe("PlayQueue", () => {
       }
     });
   });
+
+  describe("snapshot / restore (#119)", () => {
+    it("round-trips songs, index, and mode; strips url", () => {
+      const q = new PlayQueue();
+      q.add(makeSong("A"));
+      q.add(makeSong("B"));
+      q.setMode(PlayMode.Loop);
+      q.play();
+      q.next(); // current = index 1
+      const snap = q.snapshot();
+      expect(snap.currentIndex).toBe(1);
+      expect(snap.mode).toBe(PlayMode.Loop);
+      expect((snap.songs[0] as QueuedSong).url).toBeUndefined();
+      expect(snap.songs.map((s) => s.id)).toEqual(["A", "B"]);
+
+      const q2 = new PlayQueue();
+      q2.restore(snap);
+      expect(q2.list().map((s) => s.id)).toEqual(["A", "B"]);
+      expect(q2.getCurrentIndex()).toBe(1);
+      expect(q2.getMode()).toBe(PlayMode.Loop);
+      expect(q2.current()?.id).toBe("B");
+    });
+
+    it("preserves requestedBy through a snapshot", () => {
+      const q = new PlayQueue();
+      q.add({ ...makeSong("A"), requestedBy: "alice" });
+      q.play();
+      const q2 = new PlayQueue();
+      q2.restore(q.snapshot());
+      expect(q2.current()?.requestedBy).toBe("alice");
+    });
+
+    it("degrades an out-of-range index to -1 (nothing current)", () => {
+      const q = new PlayQueue();
+      const { url: _url, ...noUrl } = makeSong("A");
+      q.restore({ songs: [noUrl], currentIndex: 5, mode: PlayMode.Sequential });
+      expect(q.getCurrentIndex()).toBe(-1);
+      expect(q.current()).toBeNull();
+      expect(q.list().map((s) => s.id)).toEqual(["A"]);
+    });
+  });
+
+  // Issue #141: in Random/RandomLoop, next() picks from the shuffle bag and
+  // ignores array order, so a song spliced in by addNext (!pn) was NOT played
+  // next — it just waited for its random turn like any other song. addNext now
+  // records the insert slot on the forward stack, which next() honours first.
+  describe("addNext in random modes (issue #141)", () => {
+    for (const mode of [PlayMode.Random, PlayMode.RandomLoop]) {
+      it(`plays the inserted song next in ${mode} mode`, () => {
+        queue.setMode(mode);
+        for (const id of ["a", "b", "c", "d"]) queue.add(makeSong(id));
+        queue.play(); // current = 0 (a)
+        queue.addNext(makeSong("x"));
+        expect(queue.next()?.id).toBe("x");
+      });
+    }
+
+    it("plays consecutive inserts in the order the queue displays them", () => {
+      queue.setMode(PlayMode.RandomLoop);
+      for (const id of ["a", "b", "c", "d"]) queue.add(makeSong(id));
+      queue.play(); // current = 0 (a)
+      queue.addNext(makeSong("x"));
+      queue.addNext(makeSong("y")); // splices in front of x, as in sequential
+      expect(queue.list().map((s) => s.id)).toEqual(["a", "y", "x", "b", "c", "d"]);
+      expect(queue.next()?.id).toBe("y");
+      expect(queue.next()?.id).toBe("x");
+    });
+
+    it("honours the insert even after the shuffle bag is exhausted", () => {
+      // Random (non-loop) returns null once every song has played. Songs added
+      // afterwards must still be reachable via !pn — and with TWO of them the
+      // order can only come from the forward stack, not from the bag having a
+      // single remaining candidate.
+      queue.setMode(PlayMode.Random);
+      for (const id of ["a", "b", "c", "d"]) queue.add(makeSong(id));
+      queue.play();
+      for (let i = 0; i < 3; i++) queue.next();
+      expect(queue.next()).toBeNull(); // bag exhausted
+      queue.addNext(makeSong("x"));
+      queue.addNext(makeSong("y"));
+      queue.addNext(makeSong("z"));
+      expect(queue.next()?.id).toBe("z");
+      expect(queue.next()?.id).toBe("y");
+      expect(queue.next()?.id).toBe("x");
+    });
+
+    it("pops past a prev() marker to reach the pending insert", () => {
+      // prev() shares the forward stack, and in random mode with no history it
+      // pushes the current index and then returns null. next() must walk past
+      // those self-referencing markers instead of consuming one and giving up
+      // to the shuffle bag.
+      queue.setMode(PlayMode.Random);
+      for (const id of ["a", "b", "c", "d"]) queue.add(makeSong(id));
+      queue.play(); // a
+      queue.addNext(makeSong("x"));
+      expect(queue.prev()).toBeNull();
+      expect(queue.prev()).toBeNull();
+      expect(queue.next()?.id).toBe("x");
+    });
+
+    it("plays each song exactly once — the insert is not replayed later", () => {
+      queue.setMode(PlayMode.Random);
+      for (const id of ["a", "b", "c", "d"]) queue.add(makeSong(id));
+      queue.play(); // a
+      queue.addNext(makeSong("x"));
+      queue.addNext(makeSong("y"));
+
+      const played = [queue.current()!.id];
+      for (let i = 0; i < 5; i++) played.push(queue.next()!.id);
+      expect(queue.next()).toBeNull(); // bag exhausted
+      expect(played.slice(0, 3)).toEqual(["a", "y", "x"]);
+      expect(new Set(played).size).toBe(6);
+    });
+
+    it("keeps the insert reachable after an earlier song is removed", () => {
+      queue.setMode(PlayMode.RandomLoop);
+      for (const id of ["a", "b", "c", "d"]) queue.add(makeSong(id));
+      queue.playAt(2); // current = 2 (c)
+      queue.addNext(makeSong("x")); // [a, b, c, x, d]
+      queue.remove(0); // [b, c, x, d] — x slides from 3 to 2
+      expect(queue.next()?.id).toBe("x");
+    });
+
+    it("drops the entry when the inserted song is itself removed", () => {
+      // Leaving the stale entry behind would not throw — index 2 still exists
+      // after the removal, it just points at a different song. So the queue is
+      // arranged with exactly one song the shuffle bag can legally return:
+      // anything else means the dead forward entry was honoured.
+      queue.setMode(PlayMode.RandomLoop);
+      for (const id of ["a", "b", "c"]) queue.add(makeSong(id));
+      queue.playAt(0); // current = 0 (a), played = {0}
+      queue.next(); // b or c — two of the three are now played
+      const remaining = queue.list().find((s) => s.id !== "a" && s.id !== queue.current()!.id)!;
+      queue.addNext(makeSong("x")); // spliced at currentIndex+1
+      queue.remove(queue.getCurrentIndex() + 1); // …and removed again
+      expect(queue.list().map((s) => s.id)).not.toContain("x");
+      expect(queue.next()?.id).toBe(remaining.id);
+    });
+
+    it("never yields a stale index under interleaved inserts and removals", () => {
+      // The forward stack holds array indices, so every splice has to shift
+      // them. next() returning `undefined` here (an out-of-range index) reads
+      // as end-of-queue to BotInstance.playNext and silently stops playback.
+      queue.setMode(PlayMode.RandomLoop);
+      for (let i = 0; i < 6; i++) queue.add(makeSong(`s${i}`));
+      queue.play();
+      for (let step = 0; step < 200; step++) {
+        const roll = step % 4;
+        if (roll === 0) queue.addNext(makeSong(`x${step}`));
+        else if (roll === 1 && queue.size() > 1) queue.remove(step % queue.size());
+        else {
+          const song = queue.next();
+          expect(song === null || song === queue.current()).toBe(true);
+          if (song !== null) expect(song).toBeDefined();
+        }
+      }
+    });
+
+    it("leaves sequential/loop behaviour untouched", () => {
+      queue.setMode(PlayMode.Sequential);
+      for (const id of ["a", "b", "c"]) queue.add(makeSong(id));
+      queue.play(); // a
+      queue.addNext(makeSong("x"));
+      expect(queue.next()?.id).toBe("x");
+      expect(queue.next()?.id).toBe("b");
+      expect(queue.next()?.id).toBe("c");
+      expect(queue.next()).toBeNull();
+    });
+
+    it("still appends (no forward entry) when nothing is playing", () => {
+      queue.setMode(PlayMode.Random);
+      queue.add(makeSong("a"));
+      queue.addNext(makeSong("x")); // currentIndex is still -1 → plain push
+      expect(queue.list().map((s) => s.id)).toEqual(["a", "x"]);
+      queue.play(); // a — a stray forward entry would have hijacked this
+      expect(queue.current()?.id).toBe("a");
+    });
+  });
 });

src/audio/queue.ts

@@ -10,10 +10,23 @@ export interface QueuedSong {
   name: string;
   artist: string;
   album: string;
-  platform: "netease" | "qq" | "bilibili" | "youtube" | "local";
+  platform: "netease" | "qq" | "bilibili" | "youtube" | "local" | "kugou" | "spotify" | "jellyfin";
   url?: string; // resolved lazily at play time
   coverUrl: string;
   duration: number; // seconds
+  requestedBy?: string;
+}
+
+/**
+ * A persistable view of a queue: its songs (minus the lazily-resolved `url`),
+ * the current index, and the play mode. Used to snapshot/restore the live queue
+ * across restarts (issue #119). Derived state (playedIndices/history/forward
+ * stack) is intentionally NOT captured — restore() rebuilds it consistently.
+ */
+export interface QueueSnapshot {
+  songs: Omit<QueuedSong, "url">[];
+  currentIndex: number;
+  mode: PlayMode;
 }
 
 export class PlayQueue {
@@ -47,8 +60,12 @@ export class PlayQueue {
    * or queue empty), so the existing "add → idle bot starts playing"
    * flow continues to work.
    *
-   * Shifts playedIndices and history entries > currentIndex by +1 so
-   * their references stay valid after the splice.
+   * Shifts playedIndices, history and forwardStack entries > currentIndex
+   * by +1 so their references stay valid after the splice.
+   *
+   * In the random modes the array position alone means nothing — next()
+   * picks from the shuffle bag — so the insert slot is also recorded on
+   * the forward stack, which next() consults first (issue #141).
    */
   addNext(song: QueuedSong): void {
     if (this.currentIndex < 0 || this.songs.length === 0) {
@@ -67,6 +84,23 @@ export class PlayQueue {
     this.history = this.history.map((i) =>
       i > this.currentIndex ? i + 1 : i,
     );
+
+    this.forwardStack = this.forwardStack.map((i) =>
+      i > this.currentIndex ? i + 1 : i,
+    );
+
+    // Push AFTER the shift, or the slot we just claimed would be shifted
+    // too. Stacking makes repeated !pn play in the order the queue shows
+    // them (each insert lands in front of the previous one), matching what
+    // sequential mode does with the same array. Bounded like history: drop the
+    // OLDEST pending entry rather than refusing the newest, so the song the
+    // user just asked for is always the one that gets honoured.
+    if (this.mode === PlayMode.Random || this.mode === PlayMode.RandomLoop) {
+      this.forwardStack.push(insertAt);
+      if (this.forwardStack.length > PlayQueue.HISTORY_LIMIT) {
+        this.forwardStack.shift();
+      }
+    }
   }
 
   remove(index: number): QueuedSong | null {
@@ -93,6 +127,13 @@ export class PlayQueue {
       .filter((idx) => idx !== index)
       .map((idx) => (idx > index ? idx - 1 : idx));
 
+    // …and for the forward stack, which now also carries !pn insert slots
+    // (issue #141). Left unshifted, a removal elsewhere in the queue would
+    // silently repoint the entry at whatever song slid into that slot.
+    this.forwardStack = this.forwardStack
+      .filter((idx) => idx !== index)
+      .map((idx) => (idx > index ? idx - 1 : idx));
+
     return removed;
   }
 
@@ -145,15 +186,22 @@ export class PlayQueue {
       }
       case PlayMode.Random:
       case PlayMode.RandomLoop: {
-        // 优先回到前进栈记录的位置（prev 退回的歌）
-        if (this.forwardStack.length > 0) {
+        // 优先回到前进栈记录的位置（prev 退回的歌，或 !pn 插入的歌）。
+        // Keep popping past entries that no longer point anywhere useful,
+        // the way prev() walks past stale history entries. Without the loop a
+        // prev() that pushed the current index would swallow the pending !pn
+        // entry behind it. The range check is belt-and-braces — addNext and
+        // remove keep the stack in sync — but an out-of-range index here would
+        // set currentIndex out of bounds and hand back `undefined`, which
+        // BotInstance.playNext reads as end-of-queue and stops playback.
+        while (this.forwardStack.length > 0) {
           const target = this.forwardStack.pop()!;
-          if (target !== this.currentIndex) {
-            this.pushHistory(this.currentIndex);
-            this.currentIndex = target;
-            this.playedIndices.add(target);
-            return this.songs[target];
-          }
+          if (target < 0 || target >= this.songs.length) continue;
+          if (target === this.currentIndex) continue;
+          this.pushHistory(this.currentIndex);
+          this.currentIndex = target;
+          this.playedIndices.add(target);
+          return this.songs[target];
         }
 
         // Shuffle bag: pick uniformly from the songs not yet played this
@@ -272,4 +320,32 @@ export class PlayQueue {
   unplayedCount(): number {
     return this.songs.length - this.playedIndices.size;
   }
+
+  /**
+   * Capture the queue as a persistable snapshot (songs minus `url`, current
+   * index, mode). Songs keep their `requestedBy` so restored play-history
+   * attribution stays correct. See restore().
+   */
+  snapshot(): QueueSnapshot {
+    return {
+      songs: this.songs.map(({ url: _url, ...s }) => s),
+      currentIndex: this.currentIndex,
+      mode: this.mode,
+    };
+  }
+
+  /**
+   * Replace the queue contents from a snapshot. Rebuilds the derived
+   * playedIndices/history/forwardStack to a clean, consistent state for the
+   * restored index (an out-of-range index degrades to -1 = "nothing current").
+   */
+  restore(s: QueueSnapshot): void {
+    this.songs = s.songs.map((song) => ({ ...song }));
+    this.mode = s.mode;
+    this.currentIndex =
+      s.currentIndex >= 0 && s.currentIndex < this.songs.length ? s.currentIndex : -1;
+    this.playedIndices = new Set(this.currentIndex >= 0 ? [this.currentIndex] : []);
+    this.history = [];
+    this.forwardStack = [];
+  }
 }

src/bot/managed-voice-clients.test.ts

@@ -0,0 +1,181 @@
+import { describe, expect, it } from "vitest";
+import {
+  ManagedVoiceClientRegistry,
+  normalizeManagedVoiceClientScope,
+  normalizeManagedVoiceHost,
+} from "./managed-voice-clients.js";
+
+describe("managed voice client scope normalization", () => {
+  it("normalizes DNS host casing, whitespace, and trailing root dots", () => {
+    expect(normalizeManagedVoiceHost("  Voice.Example.COM...  ")).toBe(
+      "voice.example.com",
+    );
+    expect(
+      normalizeManagedVoiceClientScope({
+        host: "VOICE.EXAMPLE.COM.",
+        voicePort: 9987,
+      }),
+    ).toEqual({ host: "voice.example.com", voicePort: 9987 });
+  });
+
+  it("treats bracketed and equivalent expanded IPv6 literals as one host", () => {
+    expect(normalizeManagedVoiceHost("[2001:0DB8:0:0:0:0:0:1]")).toBe(
+      "2001:db8::1",
+    );
+    expect(normalizeManagedVoiceHost("2001:db8::1")).toBe("2001:db8::1");
+  });
+
+  it("rejects empty hosts and invalid voice ports", () => {
+    expect(
+      normalizeManagedVoiceClientScope({ host: " . ", voicePort: 9987 }),
+    ).toBeNull();
+    expect(
+      normalizeManagedVoiceClientScope({ host: "example.com", voicePort: 0 }),
+    ).toBeNull();
+    expect(
+      normalizeManagedVoiceClientScope({
+        host: "example.com",
+        voicePort: 65_536,
+      }),
+    ).toBeNull();
+  });
+
+});
+
+describe("ManagedVoiceClientRegistry", () => {
+  it("finds clients through normalized forms of the same scope", () => {
+    const registry = new ManagedVoiceClientRegistry();
+    const owner = Symbol("connection");
+
+    expect(
+      registry.register(
+        { host: " Voice.Example.COM. ", voicePort: 9987 },
+        42,
+        owner,
+      ),
+    ).toBe(true);
+    expect(
+      registry.has({ host: "voice.example.com", voicePort: 9987 }, 42),
+    ).toBe(true);
+  });
+
+  it("keeps different voice ports and hosts in separate scopes", () => {
+    const registry = new ManagedVoiceClientRegistry();
+    registry.register(
+      { host: "voice.example.com", voicePort: 9987 },
+      7,
+      Symbol("connection"),
+    );
+
+    expect(
+      registry.has({ host: "voice.example.com", voicePort: 9988 }, 7),
+    ).toBe(false);
+    expect(
+      registry.has({ host: "other.example.com", voicePort: 9987 }, 7),
+    ).toBe(false);
+  });
+
+  it("finds a managed bot by stable client UID across network endpoints", () => {
+    const registry = new ManagedVoiceClientRegistry();
+    const owner = Symbol("connection");
+
+    registry.register(
+      { host: "127.0.0.1", voicePort: 9987 },
+      17,
+      owner,
+      "  managed-client-uid=  ",
+    );
+
+    expect(registry.hasClientUid("managed-client-uid=")).toBe(true);
+    expect(
+      registry.has({ host: "192.168.1.10", voicePort: 20_000 }, 17),
+    ).toBe(false);
+  });
+
+  it("keeps a shared managed UID until its last owner unregisters", () => {
+    const registry = new ManagedVoiceClientRegistry();
+    const scope = { host: "203.0.113.4", voicePort: 9987 };
+    const first = Symbol("first connection");
+    const second = Symbol("second connection");
+    registry.register(scope, 18, first, "shared-client-uid=");
+    registry.register(scope, 19, second, "shared-client-uid=");
+
+    expect(registry.unregister(scope, 18, first, "shared-client-uid=")).toBe(true);
+    expect(registry.hasClientUid("shared-client-uid=")).toBe(true);
+    expect(registry.unregister(scope, 19, second, "shared-client-uid=")).toBe(true);
+    expect(registry.hasClientUid("shared-client-uid=")).toBe(false);
+  });
+
+  it("ignores missing or empty client UIDs", () => {
+    const registry = new ManagedVoiceClientRegistry();
+    registry.register(
+      { host: "203.0.113.4", voicePort: 9987 },
+      19,
+      Symbol("connection"),
+      "   ",
+    );
+
+    expect(registry.hasClientUid(undefined)).toBe(false);
+    expect(registry.hasClientUid("   ")).toBe(false);
+  });
+
+  it("uses an IPv6-safe scope key", () => {
+    const registry = new ManagedVoiceClientRegistry();
+    registry.register(
+      { host: "[2001:0db8:0:0:0:0:0:1]", voicePort: 9987 },
+      9,
+      Symbol("connection"),
+    );
+
+    expect(
+      registry.has({ host: "2001:db8::1", voicePort: 9987 }, 9),
+    ).toBe(true);
+  });
+
+  it("does not let a delayed old disconnect remove a replacement", () => {
+    const registry = new ManagedVoiceClientRegistry();
+    const scope = { host: "voice.example.com", voicePort: 9987 };
+    const oldConnection = Symbol("old connection");
+    const newConnection = Symbol("new connection");
+
+    registry.register(scope, 12, oldConnection, "managed-client-uid=");
+    registry.register(scope, 12, newConnection, "managed-client-uid=");
+
+    // The old UID owner is removed, but the replacement still owns both the
+    // scoped id and the shared stable UID.
+    expect(
+      registry.unregister(scope, 12, oldConnection, "managed-client-uid="),
+    ).toBe(true);
+    expect(registry.has(scope, 12)).toBe(true);
+    expect(registry.hasClientUid("managed-client-uid=")).toBe(true);
+    expect(
+      registry.unregister(scope, 12, newConnection, "managed-client-uid="),
+    ).toBe(true);
+    expect(registry.has(scope, 12)).toBe(false);
+    expect(registry.hasClientUid("managed-client-uid=")).toBe(false);
+  });
+
+  it.each([0, -1, 1.5, Number.NaN, Number.POSITIVE_INFINITY])(
+    "ignores invalid client id %s",
+    (clientId) => {
+      const registry = new ManagedVoiceClientRegistry();
+      const scope = { host: "voice.example.com", voicePort: 9987 };
+      const owner = Symbol("connection");
+
+      expect(registry.register(scope, clientId, owner)).toBe(false);
+      expect(registry.has(scope, clientId)).toBe(false);
+      expect(registry.unregister(scope, clientId, owner)).toBe(false);
+    },
+  );
+
+  it("has no shared module-level state between registry instances", () => {
+    const first = new ManagedVoiceClientRegistry();
+    const second = new ManagedVoiceClientRegistry();
+    const scope = { host: "voice.example.com", voicePort: 9987 };
+
+    first.register(scope, 3, Symbol("connection"));
+
+    expect(first.has(scope, 3)).toBe(true);
+    expect(second.has(scope, 3)).toBe(false);
+  });
+});

src/bot/managed-voice-clients.ts

@@ -0,0 +1,187 @@
+import { isIP } from "node:net";
+
+/** Identifies one TeamSpeak voice server. */
+export interface ManagedVoiceClientScope {
+  host: string;
+  voicePort: number;
+}
+
+export interface NormalizedManagedVoiceClientScope {
+  readonly host: string;
+  readonly voicePort: number;
+}
+
+/**
+ * An opaque value identifying the connection that owns a client id.
+ *
+ * A fresh object or Symbol per connection is recommended. Value tokens are
+ * also supported for callers that already have a unique connection id.
+ */
+export type ManagedVoiceClientOwnerToken = object | string | number | symbol;
+
+/**
+ * Normalize a TeamSpeak host for comparisons.
+ *
+ * DNS names are case-insensitive and may include a trailing root dot. IPv6
+ * literals may be supplied either bare or in URL-style brackets; valid IPv6
+ * addresses are also put into the canonical form produced by the URL parser.
+ */
+export function normalizeManagedVoiceHost(host: string): string {
+  let normalized = host.trim().toLowerCase().replace(/\.+$/, "");
+
+  if (normalized.startsWith("[") && normalized.endsWith("]")) {
+    normalized = normalized.slice(1, -1);
+  }
+
+  if (isIP(normalized) === 6) {
+    // URL's host serializer compresses equivalent IPv6 spellings. `isIP`
+    // ensures interpolation cannot be interpreted as another URL component.
+    const serialized = new URL(`http://[${normalized}]/`).hostname;
+    return serialized.slice(1, -1);
+  }
+
+  return normalized;
+}
+
+/** Return a comparable scope, or null when the runtime input is unusable. */
+export function normalizeManagedVoiceClientScope(
+  scope: ManagedVoiceClientScope,
+): NormalizedManagedVoiceClientScope | null {
+  if (
+    !scope ||
+    typeof scope.host !== "string" ||
+    typeof scope.voicePort !== "number"
+  ) {
+    return null;
+  }
+
+  const host = normalizeManagedVoiceHost(scope.host);
+  if (
+    host.length === 0 ||
+    !Number.isInteger(scope.voicePort) ||
+    scope.voicePort < 1 ||
+    scope.voicePort > 65_535
+  ) {
+    return null;
+  }
+
+  return { host, voicePort: scope.voicePort };
+}
+
+function scopeKey(scope: ManagedVoiceClientScope): string | null {
+  const normalized = normalizeManagedVoiceClientScope(scope);
+  if (!normalized) return null;
+
+  // A serialized tuple stays unambiguous when host itself contains colons.
+  return JSON.stringify([normalized.host, normalized.voicePort]);
+}
+
+function validClientId(clientId: number): boolean {
+  return Number.isSafeInteger(clientId) && clientId > 0;
+}
+
+function normalizeClientUid(clientUid: string | undefined): string | null {
+  if (typeof clientUid !== "string") return null;
+  const normalized = clientUid.trim();
+  return normalized.length > 0 ? normalized : null;
+}
+
+/**
+ * Tracks voice client ids and stable TeamSpeak identities owned by bot
+ * connections in this process. The UID path survives DNS aliases, NAT,
+ * multiple NICs, and dual-stack endpoints; scoped ids remain a fallback when
+ * a sender has not yet appeared in the receiving client's view cache.
+ *
+ * This class intentionally has no module-level singleton. BotManager owns one
+ * instance and injects it into its BotInstances so separate managers remain
+ * isolated in tests and in the same process.
+ */
+export class ManagedVoiceClientRegistry {
+  private readonly clientsByScope = new Map<
+    string,
+    Map<number, ManagedVoiceClientOwnerToken>
+  >();
+  private readonly ownersByClientUid = new Map<
+    string,
+    Set<ManagedVoiceClientOwnerToken>
+  >();
+
+  /**
+   * Register (or replace) the connection that owns a client id and, when
+   * available, add its stable UID to the managed set.
+   * Returns false when the scope or client id is invalid.
+   */
+  register(
+    scope: ManagedVoiceClientScope,
+    clientId: number,
+    ownerToken: ManagedVoiceClientOwnerToken,
+    clientUid?: string,
+  ): boolean {
+    const key = scopeKey(scope);
+    if (!key || !validClientId(clientId)) return false;
+
+    let clients = this.clientsByScope.get(key);
+    if (!clients) {
+      clients = new Map();
+      this.clientsByScope.set(key, clients);
+    }
+    clients.set(clientId, ownerToken);
+
+    const normalizedUid = normalizeClientUid(clientUid);
+    if (normalizedUid) {
+      let owners = this.ownersByClientUid.get(normalizedUid);
+      if (!owners) {
+        owners = new Set();
+        this.ownersByClientUid.set(normalizedUid, owners);
+      }
+      owners.add(ownerToken);
+    }
+    return true;
+  }
+
+  /**
+   * Remove a client only if it is still owned by this connection.
+   *
+   * The ownership check prevents a delayed disconnect from an old connection
+   * deleting a newer connection that reused the same TeamSpeak client id.
+   */
+  unregister(
+    scope: ManagedVoiceClientScope,
+    clientId: number,
+    ownerToken: ManagedVoiceClientOwnerToken,
+    clientUid?: string,
+  ): boolean {
+    const key = scopeKey(scope);
+    if (!key || !validClientId(clientId)) return false;
+
+    let removed = false;
+    const clients = this.clientsByScope.get(key);
+    if (clients?.get(clientId) === ownerToken) {
+      clients.delete(clientId);
+      if (clients.size === 0) this.clientsByScope.delete(key);
+      removed = true;
+    }
+
+    const normalizedUid = normalizeClientUid(clientUid);
+    if (normalizedUid) {
+      const owners = this.ownersByClientUid.get(normalizedUid);
+      if (owners?.delete(ownerToken)) removed = true;
+      if (owners?.size === 0) this.ownersByClientUid.delete(normalizedUid);
+    }
+    return removed;
+  }
+
+  has(scope: ManagedVoiceClientScope, clientId: number): boolean {
+    const key = scopeKey(scope);
+    if (!key || !validClientId(clientId)) return false;
+    return this.clientsByScope.get(key)?.has(clientId) ?? false;
+  }
+
+  /** TeamSpeak client UIDs are stable across endpoint aliases and NAT paths. */
+  hasClientUid(clientUid: string | undefined): boolean {
+    const normalizedUid = normalizeClientUid(clientUid);
+    return normalizedUid
+      ? (this.ownersByClientUid.get(normalizedUid)?.size ?? 0) > 0
+      : false;
+  }
+}

src/bot/manager.test.ts

@@ -9,6 +9,7 @@ import { getDefaultConfig, loadConfig, saveConfig, type BotConfig } from "../dat
 import type { Logger } from "../logger.js";
 import type { MusicProvider } from "../music/provider.js";
 import type { AvatarStore } from "../data/avatars.js";
+import type { SpotifyOAuth } from "../music/spotify/spotify-oauth.js";
 
 // removeBot only calls logger.info; provide the full shape it could touch.
 const stubLogger = {
@@ -85,3 +86,68 @@ describe("BotManager.removeBot — guest scope pruning", () => {
     expect(loadConfig(configPath).guestMode.bots).toBe("all");
   });
 });
+
+// --- Spotify OAuth threading (Task 6, C3.1) --------------------------------
+// The single process-wide SpotifyOAuth built in index.ts must reach every bot's
+// SpotifyController: index -> BotManager (trailing positional arg) -> BotInstance
+// -> controller. createBot() builds a REAL (side-effect-free) SpotifyController,
+// so we assert the shared instance surfaces via the controller's getOAuth().
+describe("BotManager — spotifyOAuth threading to bot controllers (C3.1)", () => {
+  const dirs: string[] = [];
+  let db: BotDatabase | undefined;
+
+  afterEach(() => {
+    try {
+      db?.close();
+    } catch {
+      /* ignore */
+    }
+    db = undefined;
+    for (const d of dirs) {
+      rmSync(d, { recursive: true, force: true });
+    }
+    dirs.length = 0;
+  });
+
+  it("forwards its shared SpotifyOAuth into a created bot's controller", async () => {
+    const dir = mkdtempSync(join(tmpdir(), "tsmusicbot-oauth-thread-"));
+    dirs.push(dir);
+    const configPath = join(dir, "config.json");
+    const config = getDefaultConfig();
+    saveConfig(configPath, config);
+    db = createDatabase(":memory:");
+    const permissions = createPermissionStore(db.db);
+    const provider = {} as unknown as MusicProvider;
+    const sentinel = {} as unknown as SpotifyOAuth;
+
+    const manager = new BotManager(
+      provider,
+      provider,
+      provider,
+      db,
+      config,
+      stubLogger,
+      {} as unknown as AvatarStore,
+      permissions,
+      configPath,
+      undefined, // localProvider
+      undefined, // kugouProvider
+      undefined, // spotifyProvider
+      join(dir, "spotify"), // spotifyDataDir
+      sentinel, // spotifyOAuth (the single shared instance)
+    );
+
+    const bot = await manager.createBot({
+      name: "b1",
+      serverAddress: "localhost",
+      serverPort: 9987,
+      nickname: "b1",
+    });
+
+    // Full chain observed: the manager's single shared instance is the exact
+    // one the per-bot controller now owns (getOAuth() returns it unchanged).
+    expect(bot.getSpotifyController().getOAuth()).toBe(sentinel);
+
+    bot.disconnect();
+  });
+});

src/bot/manager.ts

@@ -1,5 +1,6 @@
 import crypto from "node:crypto";
 import { EventEmitter } from "node:events";
+import path from "node:path";
 import {
   BotInstance,
   type BotInstanceOptions,
@@ -13,6 +14,8 @@ import type { Logger } from "../logger.js";
 import type { ServerProtocol } from "../ts-protocol/client.js";
 import type { AvatarStore } from "../data/avatars.js";
 import type { PermissionStore } from "../data/permissions.js";
+import type { SpotifyOAuth } from "../music/spotify/spotify-oauth.js";
+import { ManagedVoiceClientRegistry } from "./managed-voice-clients.js";
 
 /**
  * Run bot.connect() with a hard deadline. If the handshake hangs (e.g. the
@@ -70,11 +73,17 @@ export interface CreateBotParams {
 
 export class BotManager extends EventEmitter {
   private bots = new Map<string, BotInstance>();
+  private readonly managedVoiceClients = new ManagedVoiceClientRegistry();
   private neteaseProvider: MusicProvider;
   private qqProvider: MusicProvider;
   private bilibiliProvider: MusicProvider;
   private youtubeProvider: MusicProvider;
   private localProvider: MusicProvider;
+  private kugouProvider: MusicProvider;
+  private spotifyProvider: MusicProvider;
+  private jellyfinProvider: MusicProvider;
+  private spotifyDataDir: string;
+  private readonly spotifyOAuth?: SpotifyOAuth;
   private database: BotDatabase;
   private config: BotConfig;
   private logger: Logger;
@@ -92,7 +101,12 @@ export class BotManager extends EventEmitter {
     avatarStore: AvatarStore,
     permissions: PermissionStore,
     configPath: string,
-    localProvider?: MusicProvider
+    localProvider?: MusicProvider,
+    kugouProvider?: MusicProvider,
+    spotifyProvider?: MusicProvider,
+    spotifyDataDir?: string,
+    spotifyOAuth?: SpotifyOAuth,
+    jellyfinProvider?: MusicProvider
   ) {
     super();
     this.neteaseProvider = neteaseProvider;
@@ -100,6 +114,11 @@ export class BotManager extends EventEmitter {
     this.bilibiliProvider = bilibiliProvider;
     this.youtubeProvider = new YouTubeProvider();
     this.localProvider = localProvider ?? neteaseProvider;
+    this.kugouProvider = kugouProvider ?? neteaseProvider;
+    this.spotifyProvider = spotifyProvider ?? neteaseProvider;
+    this.jellyfinProvider = jellyfinProvider ?? neteaseProvider;
+    this.spotifyDataDir = spotifyDataDir ?? path.join(process.cwd(), "data", "spotify");
+    this.spotifyOAuth = spotifyOAuth;
     // Let the local provider see which uploads are still referenced by any
     // bot's queue, so it never deletes a file another queue/bot still needs.
     const referenceable = this.localProvider as Partial<{
@@ -137,10 +156,16 @@ export class BotManager extends EventEmitter {
       bilibiliProvider: this.bilibiliProvider,
       youtubeProvider: this.youtubeProvider,
       localProvider: this.localProvider,
+      kugouProvider: this.kugouProvider,
+      spotifyProvider: this.spotifyProvider,
+      jellyfinProvider: this.jellyfinProvider,
       database: this.database,
       config: this.config,
       logger: this.logger,
       avatarStore: this.avatarStore,
+      managedVoiceClients: this.managedVoiceClients,
+      spotifyDataDir: this.spotifyDataDir,
+      spotifyOAuth: this.spotifyOAuth,
     });
 
     this.bots.set(id, bot);
@@ -276,10 +301,16 @@ export class BotManager extends EventEmitter {
         bilibiliProvider: this.bilibiliProvider,
         youtubeProvider: this.youtubeProvider,
         localProvider: this.localProvider,
+        kugouProvider: this.kugouProvider,
+        spotifyProvider: this.spotifyProvider,
+        jellyfinProvider: this.jellyfinProvider,
         database: this.database,
         config: this.config,
         logger: this.logger,
         avatarStore: this.avatarStore,
+        managedVoiceClients: this.managedVoiceClients,
+        spotifyDataDir: this.spotifyDataDir,
+        spotifyOAuth: this.spotifyOAuth,
       });
       this.bots.set(id, bot);
       this.emit("botInstance", bot);
@@ -329,10 +360,16 @@ export class BotManager extends EventEmitter {
         bilibiliProvider: this.bilibiliProvider,
         youtubeProvider: this.youtubeProvider,
         localProvider: this.localProvider,
+        kugouProvider: this.kugouProvider,
+        spotifyProvider: this.spotifyProvider,
+        jellyfinProvider: this.jellyfinProvider,
         database: this.database,
         config: this.config,
         logger: this.logger,
         avatarStore: this.avatarStore,
+        managedVoiceClients: this.managedVoiceClients,
+        spotifyDataDir: this.spotifyDataDir,
+        spotifyOAuth: this.spotifyOAuth,
       });
 
       this.bots.set(saved.id, bot);

src/bot/profile.test.ts

@@ -145,3 +145,122 @@ describe("BotProfileManager custom avatar precedence", () => {
     expect(ts.clearCalls).toBe(0);
   });
 });
+
+// #148: the persisted avatar is loaded in the BotInstance constructor, before
+// tsClient.connect() has run. Loading it must not touch the wire at all.
+describe("BotProfileManager loadCustomAvatar (pre-connect load, #148)", () => {
+  let ts: ReturnType<typeof makeMockTs>;
+  beforeEach(() => { ts = makeMockTs(); });
+
+  it("does not upload or clear anything when called before connect", async () => {
+    const pm = new BotProfileManager(ts as any, noopLogger, cfgOn, "Bot");
+    pm.loadCustomAvatar(Buffer.from([7, 7, 7]));
+    await flush();
+    expect(ts.uploadCalls.length).toBe(0);
+    expect(ts.clearCalls).toBe(0);
+    expect(ts.fileTransferInitUpload).not.toHaveBeenCalled();
+  });
+
+  it("the loaded avatar is uploaded once onConnect fires", async () => {
+    const pm = new BotProfileManager(ts as any, noopLogger, cfgOn, "Bot");
+    pm.loadCustomAvatar(Buffer.from([7, 7, 7]));
+    await flush();
+    pm.onConnect();
+    await flush();
+    expect(ts.uploadCalls.length).toBe(1);
+    expect(ts.uploadCalls[0].equals(Buffer.from([7, 7, 7]))).toBe(true);
+  });
+
+  it("survives a reconnect: onConnect re-applies the loaded avatar every time", async () => {
+    const pm = new BotProfileManager(ts as any, noopLogger, cfgOn, "Bot");
+    pm.loadCustomAvatar(Buffer.from([8]));
+    pm.onConnect();
+    await flush();
+    pm.onConnect();
+    await flush();
+    expect(ts.uploadCalls.length).toBe(2);
+  });
+
+  it("loading null leaves the wire untouched and onConnect stays quiet", async () => {
+    const pm = new BotProfileManager(ts as any, noopLogger, cfgOn, "Bot");
+    pm.loadCustomAvatar(null);
+    pm.onConnect();
+    await flush();
+    expect(ts.uploadCalls.length).toBe(0);
+    expect(ts.clearCalls).toBe(0);
+  });
+
+  it("setCustomAvatar still uploads immediately after connect (post-connect edit unchanged)", async () => {
+    const pm = new BotProfileManager(ts as any, noopLogger, cfgOn, "Bot");
+    pm.loadCustomAvatar(Buffer.from([1]));
+    pm.onConnect();
+    await flush();
+    ts.uploadCalls.length = 0;
+    pm.setCustomAvatar(Buffer.from([2, 2]));
+    await flush();
+    expect(ts.uploadCalls.length).toBe(1);
+    expect(ts.uploadCalls[0].equals(Buffer.from([2, 2]))).toBe(true);
+  });
+});
+
+describe("BotProfileManager channel description follows the bot (#159)", () => {
+  const cfgChannelDesc = { ...cfgOff, channelDescEnabled: true };
+  let ts: ReturnType<typeof makeMockTs> & { cid: bigint };
+  let channelEdits: () => string[];
+
+  beforeEach(() => {
+    ts = makeMockTs() as any;
+    ts.cid = 5n;
+    (ts as any).getChannelId = () => ts.cid;
+    channelEdits = () =>
+      (ts.sendCommandNoWait as any).mock.calls
+        .map((c: any[]) => c[0] as string)
+        .filter((cmd: string) => cmd.startsWith("channeledit"));
+  });
+
+  it("clears the old channel and fills the new one when moved while playing", async () => {
+    const pm = new BotProfileManager(ts as any, noopLogger, cfgChannelDesc, "Bot");
+    await pm.onSongChange(fakeSong);
+    expect(channelEdits()).toEqual([
+      expect.stringMatching(/^channeledit cid=5 channel_description=\S+/),
+    ]);
+
+    ts.cid = 9n;
+    await pm.onChannelMoved(9n);
+
+    const edits = channelEdits();
+    expect(edits[1]).toBe("channeledit cid=5 channel_description=");
+    expect(edits[2]).toMatch(/^channeledit cid=9 channel_description=\S+/);
+  });
+
+  it("stopping after a move clears the channel the bot is in now, not the old one", async () => {
+    const pm = new BotProfileManager(ts as any, noopLogger, cfgChannelDesc, "Bot");
+    await pm.onSongChange(fakeSong);
+    ts.cid = 9n;
+    await pm.onChannelMoved(9n);
+    await pm.onSongChange(null);
+    expect(channelEdits().at(-1)).toBe("channeledit cid=9 channel_description=");
+  });
+
+  it("a move while idle touches no channel description", async () => {
+    const pm = new BotProfileManager(ts as any, noopLogger, cfgChannelDesc, "Bot");
+    ts.cid = 9n;
+    await pm.onChannelMoved(9n);
+    expect(channelEdits()).toEqual([]);
+  });
+
+  it("a move is ignored when the channel description feature is off", async () => {
+    const pm = new BotProfileManager(ts as any, noopLogger, cfgOff, "Bot");
+    await pm.onSongChange(fakeSong);
+    ts.cid = 9n;
+    await pm.onChannelMoved(9n);
+    expect(channelEdits()).toEqual([]);
+  });
+
+  it("an event for the channel the description is already in is a no-op", async () => {
+    const pm = new BotProfileManager(ts as any, noopLogger, cfgChannelDesc, "Bot");
+    await pm.onSongChange(fakeSong);
+    await pm.onChannelMoved(5n);
+    expect(channelEdits()).toHaveLength(1);
+  });
+});

src/bot/profile.ts

@@ -32,6 +32,13 @@ export class BotProfileManager {
    * pushed immediately (idle) or wait for the next stop event (playing).
    */
   private currentSong: QueuedSong | null = null;
+  /**
+   * Channel whose description currently holds our now-playing text, or null
+   * if we have not written one. Remembered so that when the bot is moved we
+   * can still clean up the channel it was taken out of (#159) — by then
+   * getChannelId() already reports the new channel.
+   */
+  private channelDescCid: bigint | null = null;
 
   /** Per-feature permission-denied flags. Reset on reconnect. */
   private permDenied = {
@@ -65,6 +72,20 @@ export class BotProfileManager {
 
   // --- Public API ---
 
+  /**
+   * Store a persisted custom avatar WITHOUT touching TeamSpeak (#148).
+   *
+   * Used during BotInstance construction, when the TS connection does not
+   * exist yet: setCustomAvatar would immediately fire the three-step file
+   * transfer (fileTransferInitUpload → uploadFileData → clientupdate) against
+   * a client that has not connected, so the upload always failed and the
+   * saved avatar never appeared. onConnect() re-applies this.customAvatar
+   * once the handshake completes, so loading it silently here loses nothing.
+   */
+  loadCustomAvatar(buffer: Buffer | null): void {
+    this.customAvatar = buffer;
+  }
+
   /**
    * Set/clear the persistent idle avatar. Pass null to remove.
    *
@@ -120,6 +141,8 @@ export class BotProfileManager {
   onConnect(): void {
     this.generation++;
     this.currentSong = null;
+    // Channel ids are per-server; never carry one across a (re)connect.
+    this.channelDescCid = null;
     this.permDenied = {
       avatar: false,
       description: false,
@@ -136,6 +159,31 @@ export class BotProfileManager {
     }
   }
 
+  /**
+   * Called when the bot itself has been moved to another channel (#159).
+   * Clears the now-playing text from the channel it left and, if a song is
+   * playing, writes it to the channel it is in now.
+   */
+  async onChannelMoved(newChannelId: bigint): Promise<void> {
+    if (!this.config.channelDescEnabled || this.permDenied.channelDesc) return;
+    const oldChannelId = this.channelDescCid;
+    if (oldChannelId === newChannelId) return;
+    try {
+      if (oldChannelId !== null) {
+        await this.tsClient.sendCommandNoWait(
+          `channeledit cid=${oldChannelId} channel_description=`,
+        );
+        this.channelDescCid = null;
+      }
+    } catch (err) {
+      this.handleFeatureError("channelDesc", err);
+      return;
+    }
+    if (this.currentSong) {
+      await this.updateChannelDescription(this.currentSong, newChannelId);
+    }
+  }
+
   getConfig(): ProfileConfig {
     return { ...this.config };
   }
@@ -386,18 +434,25 @@ export class BotProfileManager {
     return str.slice(0, end) + ellipsis;
   }
 
-  private async updateChannelDescription(song: QueuedSong | null): Promise<void> {
+  private async updateChannelDescription(
+    song: QueuedSong | null,
+    targetChannelId?: bigint,
+  ): Promise<void> {
     if (!this.config.channelDescEnabled || this.permDenied.channelDesc) return;
     try {
-      const channelId = this.tsClient.getChannelId();
-      if (channelId === 0n) return; // unknown channel
-
+      const channelId = targetChannelId ?? this.tsClient.getChannelId();
       if (!song) {
+        // Prefer the channel we actually wrote to, in case a move event
+        // was missed and the bot is somewhere else now.
+        const target = this.channelDescCid ?? channelId;
+        if (target === 0n) return; // unknown channel
         await this.tsClient.sendCommandNoWait(
-          `channeledit cid=${channelId} channel_description=`,
+          `channeledit cid=${target} channel_description=`,
         );
+        this.channelDescCid = null;
         return;
       }
+      if (channelId === 0n) return; // unknown channel
 
       const lines = [
         `\u266A \u6B63\u5728\u64AD\u653E: ${song.name} - ${song.artist}`, // ♪ 正在播放:
@@ -408,6 +463,7 @@ export class BotProfileManager {
       await this.tsClient.sendCommandNoWait(
         `channeledit cid=${channelId} channel_description=${escapeTS3(desc)}`,
       );
+      this.channelDescCid = channelId;
     } catch (err) {
       this.handleFeatureError("channelDesc", err);
     }

src/bot/song-ref.test.ts

@@ -21,6 +21,59 @@ describe("parseSongRef (#90 exact-song selection)", () => {
     expect(parseSongRef("id:185868,")).toEqual({ id: "185868", platform: null });
   });
 
+  // Issue #139: `!play id <id>` matches the "<command> <subcommand> <arg>"
+  // shape of every other command. The colon form stays supported — users have
+  // it in their chat scrollback and in older docs.
+  it("parses the space-separated id form", () => {
+    expect(parseSongRef("id 185868")).toEqual({ id: "185868", platform: null });
+    expect(parseSongRef("ID 004Z8Ihr0JIu5s")).toEqual({ id: "004Z8Ihr0JIu5s", platform: null });
+    expect(parseSongRef("id   185868")).toEqual({ id: "185868", platform: null });
+    expect(parseSongRef("id 185868.")).toEqual({ id: "185868", platform: null });
+  });
+
+  it("does not mistake a word merely starting with 'id' for an id reference", () => {
+    expect(parseSongRef("idol")).toBeNull();
+    expect(parseSongRef("identity 185868")).toBeNull();
+    expect(parseSongRef("id")).toBeNull();
+    expect(parseSongRef("id:")).toBeNull();
+    // Two remaining tokens are a search phrase, not an id.
+    expect(parseSongRef("id die for you")).toBeNull();
+  });
+
+  // Without a colon, "id" is just a word — "ID 4" and "ID Bruno" are real track
+  // titles. The space form therefore only claims tokens that could actually be
+  // an id; everything else stays a search term.
+  it("only treats the space form as an id when the token looks like one", () => {
+    expect(parseSongRef("id Bruno")).toBeNull();
+    expect(parseSongRef("id Marshmello")).toBeNull();
+    expect(parseSongRef("id 4ever")).toBeNull();
+    // …while every real id shape is still accepted.
+    expect(parseSongRef("id 4")).toEqual({ id: "4", platform: null });          // numeric
+    expect(parseSongRef("id BV1yxHQeYEuE")).toEqual({ id: "BV1yxHQeYEuE", platform: null });
+    expect(parseSongRef("id 004Z8Ihr0JIu5s")).toEqual({ id: "004Z8Ihr0JIu5s", platform: null }); // QQ mid
+    expect(parseSongRef("id a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6")).toEqual({
+      id: "a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6",
+      platform: null,
+    }); // Jellyfin GUID / Kugou hash
+  });
+
+  it("keeps the colon form unrestricted, so a short or odd id still works", () => {
+    expect(parseSongRef("id:Bruno")).toEqual({ id: "Bruno", platform: null });
+    expect(parseSongRef("id: 4ever")).toEqual({ id: "4ever", platform: null });
+  });
+
+  it("does not let the space form swallow a pasted URL", () => {
+    // `id <url>` used to fall through to the URL branches; it still must.
+    expect(parseSongRef("id https://music.163.com/song?id=185868")).toEqual({
+      id: "185868",
+      platform: "netease",
+    });
+    expect(parseSongRef("id https://y.qq.com/n/ryqq/songDetail/004Z8Ihr0JIu5s")).toEqual({
+      id: "004Z8Ihr0JIu5s",
+      platform: "qq",
+    });
+  });
+
   it("does NOT treat NetEase collection (playlist/album/artist) URLs as a song id", () => {
     // These reuse ?id= but are not songs — they should fall through to search,
     // not misresolve to getSongDetail(collectionId) and error "no song".

src/bot/song-ref.ts

@@ -18,9 +18,22 @@ export interface SongRef {
   platform: "netease" | "qq" | "bilibili" | null;
 }
 
+/**
+ * Could this token plausibly BE an id on a supported platform?
+ *   - NetEase / Kugou numeric ids      → all digits
+ *   - BiliBili                         → BV + 8-12 alphanumerics
+ *   - QQ mid (14), YouTube (11), Spotify (22), Jellyfin GUID / Kugou hash (32)
+ *                                      → 11+ chars from the id alphabet
+ * Deliberately conservative: anything rejected here just stays an ordinary
+ * search term, which is what it almost certainly was.
+ */
+function looksLikeSongId(token: string): boolean {
+  return /^(?:\d+|BV[0-9A-Za-z]{8,12}|[0-9A-Za-z_-]{11,})$/i.test(token);
+}
+
 /**
  * Detect an explicit song reference in a query. Recognizes:
- *   - `id:<id>`                         → platform from flags/default
+ *   - `id <id>` / `id:<id>`             → platform from flags/default
  *   - NetEase song URL                  → music.163.com/song?id=N (also /#/song?id=N, /song/N)
  *   - QQ song URL                       → y.qq.com/.../songDetail/MID (or ?songmid=MID)
  *   - BiliBili BVID (bare or in a URL)  → bilibili.com/video/BVxxxx, b23.tv, or BVxxxx
@@ -30,11 +43,25 @@ export function parseSongRef(raw: string): SongRef | null {
   const q = (raw ?? "").trim();
   if (!q) return null;
 
-  // Explicit "id:<id>" — platform decided by the command's flags/default.
-  // Strip trailing punctuation that tags along from a chat paste ("id:12345."
-  // / "id:12345)") — no supported id (numeric / BVID / mid) ends in those.
-  const idPrefix = /^id:\s*(\S+)$/i.exec(q);
-  if (idPrefix) return { id: idPrefix[1].replace(/[.,;)\]]+$/, ""), platform: null };
+  // Explicit id — platform decided by the command's flags/default. The
+  // separator is a colon or plain whitespace, so `id <id>` matches the
+  // `!<cmd> <sub> <arg>` shape of every other command (issue #139) while the
+  // older `id:<id>` keeps working. Strip trailing punctuation that tags along
+  // from a chat paste ("id:12345." / "id:12345)") — no supported id
+  // (numeric / BVID / mid) ends in those.
+  //
+  // The colon is an unambiguous sigil, so `id:<anything>` is always an id. A
+  // space is not: "ID 4" and "ID Bruno" are real track titles, and `id <url>`
+  // has to keep resolving as a URL. So the space form only claims tokens that
+  // could actually be an id; anything else falls through to the URL branches
+  // below and ultimately to a plain search.
+  const idPrefix = /^id(:\s*|\s+)(\S+)$/i.exec(q);
+  if (idPrefix) {
+    const id = idPrefix[2].replace(/[.,;)\]]+$/, "");
+    if (idPrefix[1].startsWith(":") || looksLikeSongId(id)) {
+      return { id, platform: null };
+    }
+  }
 
   // BiliBili BV id, bare or inside a bilibili URL (NetEase ids are numeric, so
   // a "BV..." token never collides with them).

src/bot/text-chunk.test.ts

@@ -0,0 +1,67 @@
+import { describe, it, expect } from "vitest";
+import { splitTextIntoChunks } from "./text-chunk.js";
+
+const bytes = (s: string) => Buffer.byteLength(s, "utf8");
+
+describe("splitTextIntoChunks", () => {
+  it("returns a single chunk for a short string", () => {
+    const chunks = splitTextIntoChunks("hello world", 900);
+    expect(chunks).toEqual(["hello world"]);
+  });
+
+  it("splits a multi-line string longer than maxBytes into multiple chunks on line boundaries", () => {
+    const lines = Array.from({ length: 50 }, (_, i) => `line number ${i}`);
+    const text = lines.join("\n");
+    const chunks = splitTextIntoChunks(text, 60);
+
+    expect(chunks.length).toBeGreaterThan(1);
+    for (const c of chunks) {
+      expect(bytes(c)).toBeLessThanOrEqual(60);
+    }
+    // No hard-split of any line occurred, so rejoining with "\n" is lossless.
+    expect(chunks.join("\n")).toBe(text);
+  });
+
+  it("bounds by BYTES not chars: multibyte (Chinese) content stays under the cap", () => {
+    // Each Chinese char is 3 bytes in UTF-8. 40 chars/line = 120 bytes/line.
+    const lines = Array.from({ length: 10 }, () => "歌词".repeat(20));
+    const text = lines.join("\n");
+    const chunks = splitTextIntoChunks(text, 150);
+
+    expect(chunks.length).toBeGreaterThan(1);
+    for (const c of chunks) {
+      expect(bytes(c)).toBeLessThanOrEqual(150);
+    }
+    expect(chunks.join("\n")).toBe(text);
+  });
+
+  it("hard-splits a single over-long line so no chunk exceeds the cap", () => {
+    const longLine = "a".repeat(500);
+    const chunks = splitTextIntoChunks(longLine, 100);
+
+    expect(chunks.length).toBeGreaterThan(1);
+    for (const c of chunks) {
+      expect(bytes(c)).toBeLessThanOrEqual(100);
+    }
+    // Content is preserved (hard-split introduces split points, not \n).
+    expect(chunks.join("")).toBe(longLine);
+  });
+
+  it("never splits a multibyte character across a hard-split boundary", () => {
+    // 200 Chinese chars = 600 bytes on ONE line, cap 40 bytes.
+    const longLine = "歌".repeat(200);
+    const chunks = splitTextIntoChunks(longLine, 40);
+
+    for (const c of chunks) {
+      expect(bytes(c)).toBeLessThanOrEqual(40);
+      // A clean re-decode: every chunk is valid UTF-8 with no replacement char.
+      expect(c.includes("�")).toBe(false);
+    }
+    expect(chunks.join("")).toBe(longLine);
+  });
+
+  it("preserves blank lines within a single chunk", () => {
+    const text = "a\n\nb";
+    expect(splitTextIntoChunks(text, 900)).toEqual([text]);
+  });
+});

src/bot/text-chunk.ts

@@ -0,0 +1,74 @@
+/**
+ * Split `text` into chunks whose UTF-8 byte length never exceeds `maxBytes`.
+ *
+ * TeamSpeak enforces a per-message byte cap (~1024 bytes), and the send path
+ * does no chunking, so a long single reply (e.g. full song lyrics) would be
+ * truncated or rejected. This packs whole lines greedily, breaking BETWEEN
+ * lines. When a single line is itself longer than `maxBytes`, it is hard-split
+ * on UTF-8 character boundaries so no chunk ever exceeds the cap and no
+ * multibyte character is ever cut in half.
+ *
+ * Content is preserved on rejoin, modulo the split points: chunks split only on
+ * newline boundaries rejoin losslessly with `chunks.join("\n")`; a hard-split
+ * long line rejoins with `chunks.join("")`.
+ *
+ * @param text     The full message text.
+ * @param maxBytes Max UTF-8 bytes per chunk (default 900 — under TS's ~1024 cap
+ *                 with headroom for protocol framing/escaping).
+ */
+export function splitTextIntoChunks(text: string, maxBytes = 900): string[] {
+  const chunks: string[] = [];
+  let current = "";
+
+  const flush = (): void => {
+    if (current !== "") {
+      chunks.push(current);
+      current = "";
+    }
+  };
+
+  for (const rawLine of text.split("\n")) {
+    const pieces =
+      Buffer.byteLength(rawLine, "utf8") > maxBytes
+        ? hardSplitByBytes(rawLine, maxBytes)
+        : [rawLine];
+
+    for (const piece of pieces) {
+      const candidate = current === "" ? piece : `${current}\n${piece}`;
+      if (Buffer.byteLength(candidate, "utf8") <= maxBytes) {
+        current = candidate;
+      } else {
+        // current is guaranteed non-empty here: pieces never exceed maxBytes,
+        // so an empty `current` always accepts the next piece above.
+        flush();
+        current = piece;
+      }
+    }
+  }
+
+  flush();
+  return chunks;
+}
+
+/**
+ * Break a single line into pieces each ≤ `maxBytes` UTF-8 bytes, never cutting
+ * a character (iterates code points, so surrogate pairs stay intact).
+ */
+function hardSplitByBytes(line: string, maxBytes: number): string[] {
+  const pieces: string[] = [];
+  let current = "";
+  let currentBytes = 0;
+
+  for (const ch of line) {
+    const chBytes = Buffer.byteLength(ch, "utf8");
+    if (currentBytes + chBytes > maxBytes && current !== "") {
+      pieces.push(current);
+      current = "";
+      currentBytes = 0;
+    }
+    current += ch;
+    currentBytes += chBytes;
+  }
+  if (current !== "") pieces.push(current);
+  return pieces;
+}

src/bot/voice-ducking.test.ts

@@ -0,0 +1,152 @@
+import { afterEach, describe, expect, it, vi } from "vitest";
+import { VoiceDuckingController } from "./voice-ducking.js";
+
+function makeHarness(
+  enabled = true,
+  volumePercent = 30,
+  timing = { attackMs: 50, holdMs: 100, releaseMs: 200 },
+) {
+  let now = 0;
+  const setDuckingGain = vi.fn<(gain: number, rampMs?: number) => void>();
+  const controller = new VoiceDuckingController(
+    { setDuckingGain },
+    { enabled, volumePercent },
+    { timing, now: () => now },
+  );
+
+  const advance = (milliseconds: number) => {
+    now += milliseconds;
+    vi.advanceTimersByTime(milliseconds);
+  };
+
+  return { controller, setDuckingGain, advance };
+}
+
+describe("VoiceDuckingController", () => {
+  afterEach(() => {
+    vi.useRealTimers();
+  });
+
+  it("is inert while disabled", () => {
+    vi.useFakeTimers();
+    const { controller, setDuckingGain, advance } = makeHarness(false);
+
+    controller.handleVoiceActivity(12);
+    advance(1_000);
+
+    expect(setDuckingGain).not.toHaveBeenCalled();
+    expect(controller.isDucking()).toBe(false);
+    expect(controller.activeSpeakerCount()).toBe(0);
+  });
+
+  it("attacks once, refreshes the packet deadline, then releases", () => {
+    vi.useFakeTimers();
+    const { controller, setDuckingGain, advance } = makeHarness();
+
+    controller.handleVoiceActivity(12);
+    expect(setDuckingGain).toHaveBeenCalledWith(0.3, 50);
+
+    advance(60);
+    controller.handleVoiceActivity(12);
+    expect(setDuckingGain).toHaveBeenCalledTimes(1);
+
+    // The original t=100 sweep observes the refreshed t=160 deadline.
+    advance(40);
+    expect(controller.isDucking()).toBe(true);
+    expect(setDuckingGain).toHaveBeenCalledTimes(1);
+
+    advance(60);
+    expect(controller.isDucking()).toBe(false);
+    expect(setDuckingGain).toHaveBeenLastCalledWith(1, 200);
+  });
+
+  it("stays ducked until the last overlapping speaker expires", () => {
+    vi.useFakeTimers();
+    const { controller, setDuckingGain, advance } = makeHarness();
+
+    controller.handleVoiceActivity(1);
+    advance(50);
+    controller.handleVoiceActivity(2);
+    advance(50);
+
+    expect(controller.activeSpeakerCount()).toBe(1);
+    expect(controller.isDucking()).toBe(true);
+    expect(setDuckingGain).toHaveBeenCalledTimes(1);
+
+    advance(50);
+    expect(controller.activeSpeakerCount()).toBe(0);
+    expect(setDuckingGain).toHaveBeenLastCalledWith(1, 200);
+  });
+
+  it("removes a client immediately on leave without disturbing other speakers", () => {
+    vi.useFakeTimers();
+    const { controller, setDuckingGain } = makeHarness();
+
+    controller.handleVoiceActivity(1);
+    controller.handleVoiceActivity(2);
+    controller.removeSpeaker(1);
+    expect(controller.isDucking()).toBe(true);
+    expect(controller.activeSpeakerCount()).toBe(1);
+
+    controller.removeSpeaker(2);
+    expect(controller.isDucking()).toBe(false);
+    expect(setDuckingGain).toHaveBeenLastCalledWith(1, 200);
+  });
+
+  it("retargets a live duck and smoothly restores when disabled", () => {
+    vi.useFakeTimers();
+    const { controller, setDuckingGain } = makeHarness();
+
+    controller.handleVoiceActivity(7);
+    controller.updateSettings({ enabled: true, volumePercent: 45 });
+    expect(setDuckingGain).toHaveBeenLastCalledWith(0.45, 50);
+
+    controller.updateSettings({ enabled: false, volumePercent: 45 });
+    expect(controller.isDucking()).toBe(false);
+    expect(controller.activeSpeakerCount()).toBe(0);
+    expect(setDuckingGain).toHaveBeenLastCalledWith(1, 200);
+  });
+
+  it("attacks again when speech resumes during the release window", () => {
+    vi.useFakeTimers();
+    const { controller, setDuckingGain, advance } = makeHarness();
+
+    controller.handleVoiceActivity(7);
+    advance(100);
+    expect(setDuckingGain).toHaveBeenLastCalledWith(1, 200);
+
+    advance(50);
+    controller.handleVoiceActivity(7);
+    expect(controller.isDucking()).toBe(true);
+    expect(setDuckingGain).toHaveBeenLastCalledWith(0.3, 50);
+  });
+
+  it("invalidates an old expiry callback after reset", () => {
+    vi.useFakeTimers();
+    const { controller, setDuckingGain, advance } = makeHarness();
+
+    controller.handleVoiceActivity(8);
+    controller.reset(true);
+    const callsAfterReset = setDuckingGain.mock.calls.length;
+    advance(1_000);
+
+    expect(setDuckingGain).toHaveBeenCalledTimes(callsAfterReset);
+    expect(setDuckingGain).toHaveBeenLastCalledWith(1, 0);
+  });
+
+  it("rejects invalid client ids and supports an immediate lifecycle reset", () => {
+    vi.useFakeTimers();
+    const { controller, setDuckingGain } = makeHarness();
+
+    for (const id of [0, -1, 1.5, Number.NaN]) {
+      controller.handleVoiceActivity(id);
+    }
+    expect(setDuckingGain).not.toHaveBeenCalled();
+
+    controller.handleVoiceActivity(8);
+    controller.reset(true);
+    expect(controller.isDucking()).toBe(false);
+    expect(controller.activeSpeakerCount()).toBe(0);
+    expect(setDuckingGain).toHaveBeenLastCalledWith(1, 0);
+  });
+});

src/bot/voice-ducking.ts

@@ -0,0 +1,183 @@
+export interface VoiceDuckingSettings {
+  enabled: boolean;
+  volumePercent: number;
+}
+
+export interface VoiceDuckingGainTarget {
+  setDuckingGain(gain: number, rampMs?: number): void;
+}
+
+export interface VoiceDuckingTiming {
+  attackMs: number;
+  holdMs: number;
+  releaseMs: number;
+}
+
+export const DEFAULT_VOICE_DUCKING_TIMING: Readonly<VoiceDuckingTiming> = {
+  attackMs: 50,
+  holdMs: 700,
+  releaseMs: 500,
+};
+
+interface VoiceDuckingControllerOptions {
+  timing?: Partial<VoiceDuckingTiming>;
+  now?: () => number;
+}
+
+function nonNegativeFinite(value: number | undefined, fallback: number): number {
+  return typeof value === "number" && Number.isFinite(value)
+    ? Math.max(0, value)
+    : fallback;
+}
+
+function normalizeSettings(settings: VoiceDuckingSettings): VoiceDuckingSettings {
+  return {
+    enabled: settings.enabled === true,
+    volumePercent:
+      typeof settings.volumePercent === "number" && Number.isFinite(settings.volumePercent)
+        ? Math.max(0, Math.min(100, settings.volumePercent))
+        : 30,
+  };
+}
+
+/**
+ * Converts the stream of incoming TeamSpeak voice packets into a stable
+ * ducking envelope. TeamSpeak's full-client protocol exposes voice packets,
+ * but not an explicit "stopped talking" event, so a speaker remains active
+ * for a short hold period after their most recent packet.
+ *
+ * Only one timeout is live at a time. Repeated ~20 ms voice packets update a
+ * deadline in the map instead of constantly destroying/recreating timers.
+ */
+export class VoiceDuckingController {
+  private settings: VoiceDuckingSettings;
+  private readonly timing: VoiceDuckingTiming;
+  private readonly now: () => number;
+  private readonly activeUntil = new Map<number, number>();
+  private expiryTimer: ReturnType<typeof setTimeout> | null = null;
+  private timerDueAt = Number.POSITIVE_INFINITY;
+  private timerGeneration = 0;
+  private ducking = false;
+
+  constructor(
+    private readonly target: VoiceDuckingGainTarget,
+    initialSettings: VoiceDuckingSettings,
+    options: VoiceDuckingControllerOptions = {},
+  ) {
+    this.settings = normalizeSettings(initialSettings);
+    this.timing = {
+      attackMs: nonNegativeFinite(options.timing?.attackMs, DEFAULT_VOICE_DUCKING_TIMING.attackMs),
+      holdMs: nonNegativeFinite(options.timing?.holdMs, DEFAULT_VOICE_DUCKING_TIMING.holdMs),
+      releaseMs: nonNegativeFinite(options.timing?.releaseMs, DEFAULT_VOICE_DUCKING_TIMING.releaseMs),
+    };
+    this.now = options.now ?? (() => performance.now());
+  }
+
+  handleVoiceActivity(clientId: number): void {
+    if (!this.settings.enabled || !Number.isInteger(clientId) || clientId <= 0) return;
+
+    const now = this.now();
+    this.activeUntil.set(clientId, now + this.timing.holdMs);
+
+    if (!this.ducking) {
+      this.ducking = true;
+      this.target.setDuckingGain(this.settings.volumePercent / 100, this.timing.attackMs);
+    }
+
+    this.scheduleNextSweep(now);
+  }
+
+  removeSpeaker(clientId: number): void {
+    if (!this.activeUntil.delete(clientId)) return;
+    if (this.activeUntil.size === 0) {
+      this.cancelTimer();
+      this.release();
+    }
+  }
+
+  updateSettings(settings: VoiceDuckingSettings): void {
+    const previous = this.settings;
+    this.settings = normalizeSettings(settings);
+
+    if (!this.settings.enabled) {
+      this.activeUntil.clear();
+      this.cancelTimer();
+      this.release();
+      return;
+    }
+
+    if (
+      previous.volumePercent !== this.settings.volumePercent &&
+      this.ducking
+    ) {
+      this.target.setDuckingGain(this.settings.volumePercent / 100, this.timing.attackMs);
+    }
+  }
+
+  /** Clear all activity. Disconnects use an immediate reset; disabling the
+   * feature uses updateSettings(), which returns smoothly over releaseMs. */
+  reset(immediate = true): void {
+    this.activeUntil.clear();
+    this.cancelTimer();
+    this.ducking = false;
+    this.target.setDuckingGain(1, immediate ? 0 : this.timing.releaseMs);
+  }
+
+  isDucking(): boolean {
+    return this.ducking;
+  }
+
+  activeSpeakerCount(): number {
+    return this.activeUntil.size;
+  }
+
+  private scheduleNextSweep(now = this.now()): void {
+    if (this.activeUntil.size === 0) return;
+
+    let nextDueAt = Number.POSITIVE_INFINITY;
+    for (const deadline of this.activeUntil.values()) {
+      if (deadline < nextDueAt) nextDueAt = deadline;
+    }
+
+    // Keeping an earlier timer is intentional. When it fires it will observe
+    // the refreshed deadline and schedule the remaining delay, avoiding timer
+    // churn on every incoming packet.
+    if (this.expiryTimer && this.timerDueAt <= nextDueAt) return;
+
+    this.cancelTimer();
+    const generation = ++this.timerGeneration;
+    this.timerDueAt = nextDueAt;
+    this.expiryTimer = setTimeout(() => {
+      if (generation !== this.timerGeneration) return;
+      this.expiryTimer = null;
+      this.timerDueAt = Number.POSITIVE_INFINITY;
+      this.sweepExpiredSpeakers();
+    }, Math.max(0, nextDueAt - now));
+  }
+
+  private sweepExpiredSpeakers(): void {
+    const now = this.now();
+    for (const [clientId, deadline] of this.activeUntil) {
+      if (deadline <= now) this.activeUntil.delete(clientId);
+    }
+
+    if (this.activeUntil.size > 0) {
+      this.scheduleNextSweep(now);
+    } else {
+      this.release();
+    }
+  }
+
+  private release(): void {
+    if (!this.ducking) return;
+    this.ducking = false;
+    this.target.setDuckingGain(1, this.timing.releaseMs);
+  }
+
+  private cancelTimer(): void {
+    this.timerGeneration++;
+    if (this.expiryTimer) clearTimeout(this.expiryTimer);
+    this.expiryTimer = null;
+    this.timerDueAt = Number.POSITIVE_INFINITY;
+  }
+}

src/data/config.test.ts

@@ -1,8 +1,31 @@
-import { describe, it, expect, afterEach } from "vitest";
+import { describe, it, expect, afterEach, beforeEach, vi } from "vitest";
 import { join } from "node:path";
-import { mkdtempSync, rmSync, writeFileSync, existsSync, readFileSync } from "node:fs";
+import {
+  mkdtempSync,
+  rmSync,
+  writeFileSync,
+  existsSync,
+  readFileSync,
+  readdirSync,
+  renameSync,
+} from "node:fs";
 import { tmpdir } from "node:os";
-import { getDefaultConfig, loadConfig, saveConfig, migrateLegacyConfig } from "./config.js";
+import { getDefaultConfig, loadConfig, saveConfig, migrateLegacyConfig, defaultPlatform } from "./config.js";
+
+// Wrap the fs functions config.ts uses in call-through spies so the atomic-write
+// and transient-read-error paths can be observed/forced. Everything else (mkdtemp,
+// rmSync, existsSync, …) is the real implementation via `...actual`, so all other
+// tests keep their real filesystem behavior. `vi.spyOn` can't be used here because
+// the node:fs ESM namespace is non-configurable in this setup.
+vi.mock("node:fs", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("node:fs")>();
+  return {
+    ...actual,
+    readFileSync: vi.fn(actual.readFileSync),
+    writeFileSync: vi.fn(actual.writeFileSync),
+    renameSync: vi.fn(actual.renameSync),
+  };
+});
 
 describe("config", () => {
   const dirs: string[] = [];
@@ -25,6 +48,232 @@ describe("config", () => {
     expect(config).toEqual(getDefaultConfig());
   });
 
+  it("defaults voice ducking to disabled at 30 percent", () => {
+    expect(getDefaultConfig().voiceDucking).toEqual({
+      enabled: false,
+      volumePercent: 30,
+    });
+  });
+
+  it("fills voiceDucking defaults for legacy and partial configs", () => {
+    const dir = makeTmpDir();
+    const legacyPath = join(dir, "legacy.json");
+    writeFileSync(legacyPath, JSON.stringify({ webPort: 4000 }));
+    expect(loadConfig(legacyPath).voiceDucking).toEqual({
+      enabled: false,
+      volumePercent: 30,
+    });
+
+    const partialPath = join(dir, "partial.json");
+    writeFileSync(partialPath, JSON.stringify({ voiceDucking: { enabled: true } }));
+    expect(loadConfig(partialPath).voiceDucking).toEqual({
+      enabled: true,
+      volumePercent: 30,
+    });
+  });
+
+  it("loadConfig preserves valid voiceDucking values including range endpoints", () => {
+    const dir = makeTmpDir();
+    for (const volumePercent of [0, 37.5, 100]) {
+      const path = join(dir, `voice-ducking-${volumePercent}.json`);
+      writeFileSync(
+        path,
+        JSON.stringify({ voiceDucking: { enabled: true, volumePercent } }),
+      );
+      expect(loadConfig(path).voiceDucking).toEqual({ enabled: true, volumePercent });
+    }
+  });
+
+  it("loadConfig strictly sanitizes malformed voiceDucking values", () => {
+    const dir = makeTmpDir();
+    const malformed: Array<{ name: string; json: string }> = [
+      { name: "null-block", json: JSON.stringify({ voiceDucking: null }) },
+      { name: "array-block", json: JSON.stringify({ voiceDucking: [true, 10] }) },
+      { name: "string-block", json: JSON.stringify({ voiceDucking: "on" }) },
+      {
+        name: "wrong-types",
+        json: JSON.stringify({ voiceDucking: { enabled: "yes", volumePercent: "25" } }),
+      },
+      {
+        name: "below-range",
+        json: JSON.stringify({ voiceDucking: { enabled: true, volumePercent: -1 } }),
+      },
+      {
+        name: "above-range",
+        json: JSON.stringify({ voiceDucking: { enabled: true, volumePercent: 101 } }),
+      },
+      // JSON.parse("1e309") produces Infinity, exercising the finite-number guard.
+      {
+        name: "non-finite",
+        json: '{"voiceDucking":{"enabled":true,"volumePercent":1e309}}',
+      },
+    ];
+
+    for (const testCase of malformed) {
+      const path = join(dir, `${testCase.name}.json`);
+      writeFileSync(path, testCase.json);
+      const loaded = loadConfig(path).voiceDucking;
+      if (testCase.name === "below-range" || testCase.name === "above-range" || testCase.name === "non-finite") {
+        expect(loaded).toEqual({ enabled: true, volumePercent: 30 });
+      } else {
+        expect(loaded).toEqual({ enabled: false, volumePercent: 30 });
+      }
+    }
+  });
+
+  it("defaults to the online sources with jellyfin as opt-in (disabled)", () => {
+    const config = getDefaultConfig();
+    expect(config.enabledProviders).toEqual(["netease", "qq", "bilibili", "youtube", "kugou"]);
+    expect(config.enabledProviders).not.toContain("jellyfin");
+  });
+
+  it("keeps pre-gating behavior for legacy configs without enabledProviders", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    // A config written before enabledProviders existed: no such field.
+    writeFileSync(path, JSON.stringify({ webPort: 4000 }));
+    const config = loadConfig(path);
+    expect(config.enabledProviders).toEqual(["netease", "qq", "bilibili", "youtube", "kugou"]);
+    expect(defaultPlatform(config)).toBe("netease");
+  });
+
+  it("defaultPlatform follows the fixed priority order", () => {
+    const config = getDefaultConfig();
+    expect(defaultPlatform(config)).toBe("netease");
+
+    // Jellyfin ranks after the online music platforms…
+    config.enabledProviders = ["netease", "jellyfin"];
+    expect(defaultPlatform(config)).toBe("netease");
+    // …but ahead of the video sites…
+    config.enabledProviders = ["bilibili", "jellyfin", "youtube"];
+    expect(defaultPlatform(config)).toBe("jellyfin");
+    // …and is the default when it is the only enabled source.
+    config.enabledProviders = ["jellyfin"];
+    expect(defaultPlatform(config)).toBe("jellyfin");
+    // Nothing enabled → netease fallback (the gate then reports it disabled).
+    config.enabledProviders = [];
+    expect(defaultPlatform(config)).toBe("netease");
+  });
+
+  // --- #126: an explicit operator default source ---
+
+  it("defaultPlatform is null by default (follow the priority order)", () => {
+    expect(getDefaultConfig().defaultPlatform).toBeNull();
+  });
+
+  it("defaultPlatform() honors an explicit, enabled preference over the priority order", () => {
+    const config = getDefaultConfig();
+    // Priority would pick netease; a Bilibili-loving server sets B站 instead (#126).
+    config.defaultPlatform = "bilibili";
+    expect(defaultPlatform(config)).toBe("bilibili");
+  });
+
+  it("defaultPlatform() ignores a preference whose source is not enabled", () => {
+    const config = getDefaultConfig();
+    config.defaultPlatform = "jellyfin"; // opt-in, not enabled in the default config
+    // Falls back to the fixed priority order (netease)…
+    expect(defaultPlatform(config)).toBe("netease");
+    // …until the preferred source is actually enabled.
+    config.enabledProviders = [...config.enabledProviders, "jellyfin"];
+    expect(defaultPlatform(config)).toBe("jellyfin");
+  });
+
+  it("loadConfig keeps a valid, enabled defaultPlatform", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    writeFileSync(path, JSON.stringify({ defaultPlatform: "bilibili" }));
+    const config = loadConfig(path);
+    expect(config.defaultPlatform).toBe("bilibili");
+    expect(defaultPlatform(config)).toBe("bilibili");
+  });
+
+  it("loadConfig nulls a defaultPlatform that is unknown, disabled, or the wrong type", () => {
+    const dir = makeTmpDir();
+    // Unknown provider name.
+    const p1 = join(dir, "c1.json");
+    writeFileSync(p1, JSON.stringify({ defaultPlatform: "bogus" }));
+    expect(loadConfig(p1).defaultPlatform).toBeNull();
+    // Known provider, but not in enabledProviders.
+    const p2 = join(dir, "c2.json");
+    writeFileSync(p2, JSON.stringify({ enabledProviders: ["netease"], defaultPlatform: "bilibili" }));
+    expect(loadConfig(p2).defaultPlatform).toBeNull();
+    // Wrong type.
+    const p3 = join(dir, "c3.json");
+    writeFileSync(p3, JSON.stringify({ defaultPlatform: 42 }));
+    expect(loadConfig(p3).defaultPlatform).toBeNull();
+  });
+
+  it("round-trips defaultPlatform through save/load", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    saveConfig(path, { ...getDefaultConfig(), defaultPlatform: "qq" });
+    expect(loadConfig(path).defaultPlatform).toBe("qq");
+  });
+
+  it("respects an explicit jellyfin-only enabledProviders from disk", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    // e.g. a config persisted by the short-lived jellyfin-by-default builds.
+    writeFileSync(path, JSON.stringify({ enabledProviders: ["jellyfin"] }));
+    const config = loadConfig(path);
+    expect(config.enabledProviders).toEqual(["jellyfin"]);
+    expect(defaultPlatform(config)).toBe("jellyfin");
+  });
+
+  // ── audioQuality persistence (#125) ─────────────────────────────────────
+  it("defaults audioQuality to each provider's in-memory default", () => {
+    const config = getDefaultConfig();
+    expect(config.audioQuality).toEqual({
+      netease: "exhigh",
+      qq: "exhigh",
+      bilibili: "high",
+      kugou: "128",
+      jellyfin: "direct",
+    });
+  });
+
+  it("fills audioQuality defaults for a legacy config without the field", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    writeFileSync(path, JSON.stringify({ webPort: 4000 }));
+    const config = loadConfig(path);
+    expect(config.audioQuality).toEqual(getDefaultConfig().audioQuality);
+  });
+
+  it("round-trips a saved audioQuality through save/load", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    const config = getDefaultConfig();
+    config.audioQuality = {
+      netease: "lossless",
+      qq: "flac",
+      bilibili: "high",
+      kugou: "flac",
+      jellyfin: "320",
+    };
+    saveConfig(path, config);
+    const loaded = loadConfig(path);
+    expect(loaded.audioQuality).toEqual(config.audioQuality);
+  });
+
+  it("coerces missing / non-string audioQuality fields to defaults", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    // netease valid, qq blank, bilibili wrong type, kugou missing, jellyfin valid.
+    writeFileSync(
+      path,
+      JSON.stringify({ audioQuality: { netease: "lossless", qq: "  ", bilibili: 320, jellyfin: "192" } }),
+    );
+    const config = loadConfig(path);
+    expect(config.audioQuality).toEqual({
+      netease: "lossless",
+      qq: "exhigh", // blank → default
+      bilibili: "high", // non-string → default
+      kugou: "128", // missing → default
+      jellyfin: "192",
+    });
+  });
+
   it("creates config file on save", () => {
     const dir = makeTmpDir();
     const path = join(dir, "sub", "config.json");
@@ -205,3 +454,250 @@ describe("adminGroups normalization", () => {
     expect(loadAdminGroups({ adminGroups: "6" })).toEqual([]);
   });
 });
+
+describe("spotify config", () => {
+  it("defaults are present and disabled", () => {
+    const c = getDefaultConfig();
+    expect(c.spotify).toEqual({
+      enabled: false,
+      backend: "auto",
+      clientId: "",
+      clientSecret: "",
+      deviceName: "TSMusicBot",
+      bitrate: 320,
+    });
+  });
+
+  it("loadConfig coerces bad spotify values back to safe defaults", () => {
+    const dir = mkdtempSync(join(tmpdir(), "cfg-"));
+    const p = join(dir, "config.json");
+    writeFileSync(
+      p,
+      JSON.stringify({
+        spotify: { enabled: "yes", backend: "bogus", bitrate: 7, clientId: 5 },
+      })
+    );
+    const c = loadConfig(p);
+    expect(c.spotify.enabled).toBe(false); // non-boolean → false
+    expect(c.spotify.backend).toBe("auto"); // invalid enum → auto
+    expect(c.spotify.bitrate).toBe(320); // invalid → 320
+    expect(c.spotify.clientId).toBe(""); // non-string → ""
+    expect(c.spotify.deviceName).toBe("TSMusicBot"); // missing → default
+  });
+
+  it("loadConfig preserves valid spotify values", () => {
+    const dir = mkdtempSync(join(tmpdir(), "cfg-"));
+    const p = join(dir, "config.json");
+    writeFileSync(
+      p,
+      JSON.stringify({
+        spotify: {
+          enabled: true,
+          backend: "librespot",
+          clientId: "abc",
+          clientSecret: "def",
+          deviceName: "MyBot",
+          bitrate: 160,
+        },
+      })
+    );
+    const c = loadConfig(p);
+    expect(c.spotify).toEqual({
+      enabled: true,
+      backend: "librespot",
+      clientId: "abc",
+      clientSecret: "def",
+      deviceName: "MyBot",
+      bitrate: 160,
+    });
+  });
+});
+
+// --- R2-1: saveConfig must write atomically (temp file + rename), never truncate ---
+
+describe("saveConfig atomic write", () => {
+  const dirs: string[] = [];
+  function makeTmpDir(): string {
+    const dir = mkdtempSync(join(tmpdir(), "tsmb-atomic-"));
+    dirs.push(dir);
+    return dir;
+  }
+  beforeEach(() => {
+    vi.clearAllMocks(); // reset call history, keep the call-through implementations
+  });
+  afterEach(() => {
+    for (const d of dirs) rmSync(d, { recursive: true, force: true });
+    dirs.length = 0;
+  });
+
+  it("round-trips (save then load equals) and leaves NO .tmp file behind", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    const config = { ...getDefaultConfig(), webPort: 4567, adminPassword: "pw" };
+
+    saveConfig(path, config);
+
+    expect(loadConfig(path)).toEqual(config);
+    // No temp remnants in the target directory.
+    expect(readdirSync(dir).filter((f) => f.includes(".tmp"))).toEqual([]);
+  });
+
+  it("writes via a same-dir temp file then renameSync onto the final path", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+
+    saveConfig(path, getDefaultConfig());
+
+    expect(vi.mocked(renameSync)).toHaveBeenCalled();
+    const [from, to] = vi.mocked(renameSync).mock.calls[0] as [string, string];
+    expect(to).toBe(path); // renamed ONTO the real path
+    expect(String(from)).not.toBe(path); // ...from a distinct temp file
+    expect(join(String(from), "..")).toBe(join(path, "..")); // ...in the SAME directory
+  });
+
+  it("does not corrupt a pre-existing valid config when saving over it", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    saveConfig(path, { ...getDefaultConfig(), adminPassword: "first", webPort: 1234 });
+
+    // Overwrite with a different, fully-formed config.
+    saveConfig(path, { ...getDefaultConfig(), adminPassword: "second", webPort: 9999 });
+
+    const loaded = loadConfig(path);
+    expect(loaded.adminPassword).toBe("second");
+    expect(loaded.webPort).toBe(9999);
+    // The on-disk file is a single complete JSON document (no partial/truncated write).
+    expect(() => JSON.parse(readFileSync(path, "utf-8"))).not.toThrow();
+    expect(readdirSync(dir).filter((f) => f.includes(".tmp"))).toEqual([]);
+  });
+
+  it("cleans up the temp file (no .tmp remnant) when the rename fails", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    vi.mocked(renameSync).mockImplementationOnce(() => {
+      throw new Error("rename boom");
+    });
+
+    expect(() => saveConfig(path, getDefaultConfig())).toThrow(/rename boom/);
+    // The failed write left no temp file lying around.
+    expect(readdirSync(dir).filter((f) => f.includes(".tmp"))).toEqual([]);
+  });
+});
+
+// --- R2-2: loadConfig must not treat a transient/corrupt read as "missing" ---
+
+describe("loadConfig error handling", () => {
+  const dirs: string[] = [];
+  function makeTmpDir(): string {
+    const dir = mkdtempSync(join(tmpdir(), "tsmb-load-"));
+    dirs.push(dir);
+    return dir;
+  }
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+  afterEach(() => {
+    for (const d of dirs) rmSync(d, { recursive: true, force: true });
+    dirs.length = 0;
+  });
+
+  it("(a) ENOENT (missing file) returns defaults — unchanged first-run behavior", () => {
+    const dir = makeTmpDir();
+    expect(loadConfig(join(dir, "config.json"))).toEqual(getDefaultConfig());
+  });
+
+  it("(b) a non-ENOENT read error (EBUSY) rethrows instead of returning defaults", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    // A REAL config exists on disk; a transient lock must NOT collapse to defaults
+    // (the caller would otherwise overwrite this real config with defaults).
+    saveConfig(path, { ...getDefaultConfig(), adminPassword: "keep-me" });
+    vi.mocked(readFileSync).mockImplementationOnce(() => {
+      const err = new Error("EBUSY: resource busy or locked") as NodeJS.ErrnoException;
+      err.code = "EBUSY";
+      throw err;
+    });
+
+    expect(() => loadConfig(path)).toThrow(/EBUSY/);
+    // The on-disk config is untouched and still readable once the lock clears.
+    expect(loadConfig(path).adminPassword).toBe("keep-me");
+  });
+
+  it("(c) corrupt JSON returns defaults AND backs up the original to *.corrupt-*", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    const garbage = "{ not: valid json, ";
+    writeFileSync(path, garbage, "utf-8");
+
+    const loaded = loadConfig(path);
+
+    expect(loaded).toEqual(getDefaultConfig());
+    const backups = readdirSync(dir).filter((f) => f.includes(".corrupt-"));
+    expect(backups.length).toBeGreaterThan(0);
+    // The corrupt original is preserved verbatim (recoverable, never deleted).
+    expect(readFileSync(join(dir, backups[0]), "utf-8")).toBe(garbage);
+  });
+
+  // (d)/(e) Valid JSON that is NOT a non-null object (null / [] / 42 / "str") passes
+  // JSON.parse but would throw a raw TypeError in the per-field sanitize block
+  // (property access on a non-object), bypassing the corrupt-backup path. It must be
+  // treated EXACTLY like corrupt JSON: back up to *.corrupt-* (original preserved),
+  // return defaults — NOT a thrown TypeError, and NOT a silent defaults-with-no-backup.
+  it("(d) a `null` config is treated as corrupt: defaults + *.corrupt-* backup (original preserved)", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    writeFileSync(path, "null", "utf-8");
+
+    let loaded: ReturnType<typeof getDefaultConfig>;
+    expect(() => {
+      loaded = loadConfig(path);
+    }).not.toThrow();
+
+    expect(loaded!).toEqual(getDefaultConfig());
+    const backups = readdirSync(dir).filter((f) => f.includes(".corrupt-"));
+    expect(backups.length).toBeGreaterThan(0);
+    expect(readFileSync(join(dir, backups[0]), "utf-8")).toBe("null");
+  });
+
+  it("(e) a non-object config (`[]` / `42`) is backed up + defaults, not a thrown TypeError", () => {
+    for (const content of ["[]", "42"]) {
+      const dir = makeTmpDir();
+      const path = join(dir, "config.json");
+      writeFileSync(path, content, "utf-8");
+
+      let loaded: ReturnType<typeof getDefaultConfig>;
+      expect(() => {
+        loaded = loadConfig(path);
+      }).not.toThrow();
+
+      expect(loaded!).toEqual(getDefaultConfig());
+      const backups = readdirSync(dir).filter((f) => f.includes(".corrupt-"));
+      expect(backups.length).toBeGreaterThan(0);
+      expect(readFileSync(join(dir, backups[0]), "utf-8")).toBe(content);
+    }
+  });
+
+  it("defaults savedQueuesEnabled and playKeepsQueue to false", () => {
+    const c = getDefaultConfig();
+    expect(c.savedQueuesEnabled).toBe(false);
+    expect(c.playKeepsQueue).toBe(false);
+  });
+
+  it("coerces non-boolean savedQueues/playKeepsQueue values to false on load", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    writeFileSync(path, JSON.stringify({ savedQueuesEnabled: "yes", playKeepsQueue: 1 }));
+    const c = loadConfig(path);
+    expect(c.savedQueuesEnabled).toBe(false);
+    expect(c.playKeepsQueue).toBe(false);
+  });
+
+  it("preserves savedQueues/playKeepsQueue true when explicitly enabled", () => {
+    const dir = makeTmpDir();
+    const path = join(dir, "config.json");
+    writeFileSync(path, JSON.stringify({ savedQueuesEnabled: true, playKeepsQueue: true }));
+    const c = loadConfig(path);
+    expect(c.savedQueuesEnabled).toBe(true);
+    expect(c.playKeepsQueue).toBe(true);
+  });
+});

src/data/config.ts

@@ -1,4 +1,12 @@
-import { readFileSync, writeFileSync, mkdirSync, existsSync, copyFileSync, rmSync } from "node:fs";
+import {
+  readFileSync,
+  writeFileSync,
+  mkdirSync,
+  existsSync,
+  copyFileSync,
+  rmSync,
+  renameSync,
+} from "node:fs";
 import { dirname } from "node:path";
 import type { BotAccess, GuestPermissions } from "./permissions.js";
 import { GUEST_PERMISSION_FLAGS } from "./permissions.js";
@@ -9,6 +17,96 @@ export interface GuestModeConfig {
   permissions: GuestPermissions;
 }
 
+export interface SpotifyConfig {
+  enabled: boolean;
+  backend: "auto" | "go-librespot" | "librespot";
+  clientId: string;
+  clientSecret: string;
+  deviceName: string;
+  bitrate: number;
+}
+
+export interface JellyfinConfig {
+  /** Base URL of the Jellyfin server, e.g. "https://jellyfin.example.com". */
+  serverUrl: string;
+  authMode: "userpass" | "apikey";
+  // userpass mode
+  username: string;
+  password: string;
+  // apikey mode: admin API key + the user whose library/favorites/playlists are used
+  apiKey: string;
+  userId: string;
+}
+
+/**
+ * Per-provider audio quality (音质), persisted so a restart keeps the user's
+ * choice instead of resetting each provider to its in-memory default (#125).
+ * The values are the same strings the WebUI/REST `POST /api/music/quality`
+ * endpoint sends and each provider's setQuality() accepts; on startup they are
+ * replayed onto the (shared, process-wide) providers. Providers ignore/normalize
+ * unknown values, so a stale/hand-edited entry can never break playback.
+ */
+export interface AudioQualityConfig {
+  netease: string;
+  qq: string;
+  bilibili: string;
+  kugou: string;
+  jellyfin: string;
+}
+
+export interface VoiceDuckingConfig {
+  enabled: boolean;
+  /** Percentage of the normal playback volume retained while someone speaks. */
+  volumePercent: number;
+}
+
+/**
+ * Providers gated by `enabledProviders`. Not listed here:
+ *  - "local"   → governed by the existing `localAudioEnabled` flag
+ *  - "spotify" → governed by the existing `spotify.enabled` flag
+ */
+export const GATEABLE_PROVIDERS = [
+  "jellyfin",
+  "netease",
+  "qq",
+  "bilibili",
+  "youtube",
+  "kugou",
+] as const;
+export type GateableProvider = (typeof GATEABLE_PROVIDERS)[number];
+
+/** Whether a platform may be used for search/playback under the current config. */
+export function isProviderEnabled(config: BotConfig, platform: string): boolean {
+  if (platform === "local") return config.localAudioEnabled !== false;
+  if (platform === "spotify") return config.spotify.enabled;
+  return config.enabledProviders.includes(platform as GateableProvider);
+}
+
+/**
+ * The default platform for !play/!add/!playlist/!album and all REST/WebUI calls.
+ *
+ * An explicit user preference (`config.defaultPlatform`) wins whenever it points
+ * at a source that is currently enabled — this lets e.g. a Bilibili-loving server
+ * set B站 as the default so `!play <歌名>` needs no `-b` flag (issue #126). The
+ * enabled-guard here matters at runtime too: if the operator later disables the
+ * preferred source, we must fall through instead of returning a dead default.
+ *
+ * With no (usable) preference we fall back to the first enabled provider in a
+ * fixed priority order (netease with the default config; jellyfin ranks after
+ * the online music platforms because it is an opt-in source, but ahead of the
+ * video sites for users who run it as their only music library). Falls back to
+ * "netease" when nothing is enabled so callers always get a provider — the
+ * enabled-gate then produces the friendly error.
+ */
+export function defaultPlatform(config: BotConfig): GateableProvider {
+  const pref = config.defaultPlatform;
+  if (pref && config.enabledProviders.includes(pref)) return pref;
+  for (const p of ["netease", "qq", "kugou", "jellyfin", "bilibili", "youtube"] as const) {
+    if (config.enabledProviders.includes(p)) return p;
+  }
+  return "netease";
+}
+
 export interface BotConfig {
   webPort: number;
   locale: "zh" | "en";
@@ -21,9 +119,24 @@ export interface BotConfig {
   adminGroups: number[];
   autoReturnDelay: number;
   autoPauseOnEmpty: boolean;
+  /** Lower music volume while voice from another client is being received. */
+  voiceDucking: VoiceDuckingConfig;
   idleTimeoutMinutes: number;
   /** Enable uploading and playback of server-stored local audio files. */
   localAudioEnabled: boolean;
+  /**
+   * Enable named save/load of queues (chat + web) AND auto-restore of the live
+   * queue across a restart. Admin-controlled; default false so nothing is
+   * persisted/restored until an operator opts in.
+   */
+  savedQueuesEnabled: boolean;
+  /**
+   * When true, a single-song immediate !play (chat) / play-song (web) inserts
+   * after the current track and jumps to it instead of clearing the queue, so
+   * the rest of the queue survives and continues afterwards. Default false
+   * keeps today's clear-and-play behavior.
+   */
+  playKeepsQueue: boolean;
   // Public base URL used when generating share links (e.g. the bot专属链接).
   // Leave empty to use the browser's current origin. Example:
   //   "https://music.example.com" or "http://1.2.3.4:3000"
@@ -33,6 +146,26 @@ export interface BotConfig {
   // behind HTTPS-terminating proxies.
   trustProxy: boolean;
   guestMode: GuestModeConfig;
+  spotify: SpotifyConfig;
+  jellyfin: JellyfinConfig;
+  /** Persisted per-provider audio quality (音质), restored on startup (#125). */
+  audioQuality: AudioQualityConfig;
+  /**
+   * Which gateable providers are active (see GATEABLE_PROVIDERS). Default is
+   * the online sources (NetEase/QQ/Bilibili/YouTube/Kugou); jellyfin is an
+   * opt-in extra that must be listed here (Settings → Jellyfin 音乐库 toggles
+   * it). Sources not listed stay disabled — the NetEase/QQ embedded sidecar
+   * API servers must not start (or bind ports 3001/3200) unless enabled.
+   */
+  enabledProviders: GateableProvider[];
+  /**
+   * Optional operator-chosen default source for commands/REST/WebUI calls that
+   * omit a platform (issue #126). When set to an enabled gateable provider it
+   * overrides the fixed priority order in defaultPlatform(); `null` (the default)
+   * keeps that priority order. loadConfig cleans stale/unknown/disabled values
+   * back to null.
+   */
+  defaultPlatform: GateableProvider | null;
 }
 
 export function getDefaultConfig(): BotConfig {
@@ -51,8 +184,14 @@ export function getDefaultConfig(): BotConfig {
     // command, which is unreliable on some servers (it can time out when other
     // clients are present). Users can opt in from the web UI.
     autoPauseOnEmpty: false,
+    voiceDucking: {
+      enabled: false,
+      volumePercent: 30,
+    },
     idleTimeoutMinutes: 0,
     localAudioEnabled: true,
+    savedQueuesEnabled: false,
+    playKeepsQueue: false,
     publicUrl: "",
     trustProxy: false,
     guestMode: {
@@ -69,15 +208,99 @@ export function getDefaultConfig(): BotConfig {
         playCollection: false,
       },
     },
+    spotify: {
+      enabled: false,
+      backend: "auto",
+      clientId: "",
+      clientSecret: "",
+      deviceName: "TSMusicBot",
+      bitrate: 320,
+    },
+    jellyfin: {
+      serverUrl: "",
+      authMode: "userpass",
+      username: "",
+      password: "",
+      apiKey: "",
+      userId: "",
+    },
+    // Mirrors each provider's own in-memory default quality; overwritten on
+    // startup once the user has changed a quality (persisted via #125).
+    audioQuality: {
+      netease: "exhigh",
+      qq: "exhigh",
+      bilibili: "high",
+      kugou: "128",
+      jellyfin: "direct",
+    },
+    enabledProviders: ["netease", "qq", "bilibili", "youtube", "kugou"],
+    defaultPlatform: null,
   };
 }
 
+/**
+ * Move an unusable config aside to a timestamped `*.corrupt-*` backup so the data
+ * stays recoverable (it is NEVER deleted), for both the corrupt-JSON case and the
+ * parses-but-not-an-object case. Prefer an atomic same-dir rename; if that fails,
+ * copy instead. If it can't be preserved at all, rethrow rather than let the caller
+ * overwrite unrecoverable data.
+ */
+function backupCorruptConfig(path: string): void {
+  const backup = `${path}.corrupt-${Date.now()}`;
+  try {
+    renameSync(path, backup);
+  } catch {
+    try {
+      copyFileSync(path, backup);
+    } catch (backupErr) {
+      throw backupErr;
+    }
+  }
+}
+
 export function loadConfig(path: string): BotConfig {
   const defaults = getDefaultConfig();
-  try {
-    const raw = readFileSync(path, "utf-8");
-    const partial = JSON.parse(raw) as Partial<BotConfig>;
 
+  // Distinguish the three failure modes so a *real* on-disk config is NEVER
+  // silently replaced with defaults (the caller saveConfig()s right after load,
+  // which would otherwise erase spotify creds / adminPassword / adminGroups /
+  // guestMode permanently):
+  //   (a) file ABSENT (ENOENT) — normal first run → defaults.
+  //   (b) any OTHER read error (EBUSY/EACCES/EPERM/EISDIR/…) on an existing file —
+  //       rethrow (fail-fast at boot). A loud crash beats silent credential loss.
+  //   (c) file readable but JSON.parse fails (corrupt) — back the file up first
+  //       (never delete it), THEN return defaults so boot can proceed.
+  let raw: string;
+  try {
+    raw = readFileSync(path, "utf-8");
+  } catch (err) {
+    if ((err as NodeJS.ErrnoException).code === "ENOENT") {
+      return defaults; // (a) missing file — first run
+    }
+    throw err; // (b) transient/permission error on an existing file — do not clobber it
+  }
+
+  let parsed: unknown;
+  try {
+    parsed = JSON.parse(raw);
+  } catch {
+    // (c) Corrupt content: move the unreadable file aside to a timestamped backup
+    // so the data stays recoverable, then fall back to defaults.
+    backupCorruptConfig(path);
+    return defaults;
+  }
+
+  // (d) Parses cleanly but is NOT a non-null object (e.g. `null`, `42`, `"str"`,
+  // `[]`). The per-field sanitize below assumes an object and would throw a raw
+  // TypeError (or silently spread junk), bypassing the corrupt-backup path. Treat
+  // it EXACTLY like corrupt JSON: back it up (never delete), then return defaults.
+  if (typeof parsed !== "object" || parsed === null || Array.isArray(parsed)) {
+    backupCorruptConfig(path);
+    return defaults;
+  }
+  const partial = parsed as Partial<BotConfig>;
+
+  {
     // Normalize/sanitize guestMode on load. The WRITE path (POST /api/bot/settings)
     // sanitizes too, but a hand-edited/legacy/corrupt config.json reaches the gate
     // directly — so coerce it here as well, mirroring that write-path logic.
@@ -118,20 +341,152 @@ export function loadConfig(path: string): BotConfig {
         )
       : defaults.adminGroups;
 
+    const partialSp = (partial.spotify ?? {}) as Partial<SpotifyConfig>;
+    const validBackends = ["auto", "go-librespot", "librespot"] as const;
+    const validBitrates = [96, 160, 320];
+    const spotify: SpotifyConfig = {
+      enabled: partialSp.enabled === true,
+      backend: (validBackends as readonly string[]).includes(partialSp.backend as string)
+        ? (partialSp.backend as SpotifyConfig["backend"])
+        : defaults.spotify.backend,
+      clientId: typeof partialSp.clientId === "string" ? partialSp.clientId : defaults.spotify.clientId,
+      clientSecret:
+        typeof partialSp.clientSecret === "string" ? partialSp.clientSecret : defaults.spotify.clientSecret,
+      deviceName:
+        typeof partialSp.deviceName === "string" && partialSp.deviceName.trim()
+          ? partialSp.deviceName
+          : defaults.spotify.deviceName,
+      bitrate: validBitrates.includes(partialSp.bitrate as number)
+        ? (partialSp.bitrate as number)
+        : defaults.spotify.bitrate,
+    };
+
+    // Sanitize the jellyfin block on load, mirroring the spotify handling: a
+    // hand-edited/legacy config.json must never smuggle wrong shapes past the
+    // gate. Unknown/invalid sub-fields fall back to defaults.
+    const partialJf = (partial.jellyfin ?? {}) as Partial<JellyfinConfig>;
+    const jellyfin: JellyfinConfig = {
+      serverUrl:
+        typeof partialJf.serverUrl === "string"
+          ? partialJf.serverUrl.trim().replace(/\/+$/, "")
+          : defaults.jellyfin.serverUrl,
+      authMode:
+        partialJf.authMode === "apikey" ? "apikey" : defaults.jellyfin.authMode,
+      username:
+        typeof partialJf.username === "string" ? partialJf.username : defaults.jellyfin.username,
+      password:
+        typeof partialJf.password === "string" ? partialJf.password : defaults.jellyfin.password,
+      apiKey: typeof partialJf.apiKey === "string" ? partialJf.apiKey : defaults.jellyfin.apiKey,
+      userId: typeof partialJf.userId === "string" ? partialJf.userId : defaults.jellyfin.userId,
+    };
+
+    // enabledProviders → known providers only; a non-array falls back to the
+    // default (online sources, jellyfin off). An explicitly-empty array is
+    // respected (operator chose to disable every gateable source).
+    const enabledProviders = Array.isArray(partial.enabledProviders)
+      ? partial.enabledProviders.filter((p): p is GateableProvider =>
+          (GATEABLE_PROVIDERS as readonly string[]).includes(p as string),
+        )
+      : defaults.enabledProviders;
+
+    // Strict-coerce the two feature flags exactly like spotify.enabled so a
+    // hand-edited / legacy / corrupt config.json can never silently enable
+    // them (`"yes"`, `1`, `null` → false; only a literal `true` enables).
+    const savedQueuesEnabled = partial.savedQueuesEnabled === true;
+    const playKeepsQueue = partial.playKeepsQueue === true;
+
+    // Voice ducking is opt-in and the retained-volume percentage is consumed
+    // directly by the audio path. Only a plain-object block with correctly
+    // typed, finite and in-range fields may override the safe defaults.
+    const rawVoiceDucking = partial.voiceDucking;
+    const partialVoiceDucking =
+      rawVoiceDucking !== null &&
+      typeof rawVoiceDucking === "object" &&
+      !Array.isArray(rawVoiceDucking)
+        ? (rawVoiceDucking as Partial<VoiceDuckingConfig>)
+        : {};
+    const rawVolumePercent = partialVoiceDucking.volumePercent;
+    const voiceDucking: VoiceDuckingConfig = {
+      enabled:
+        typeof partialVoiceDucking.enabled === "boolean"
+          ? partialVoiceDucking.enabled
+          : defaults.voiceDucking.enabled,
+      volumePercent:
+        typeof rawVolumePercent === "number" &&
+        Number.isFinite(rawVolumePercent) &&
+        rawVolumePercent >= 0 &&
+        rawVolumePercent <= 100
+          ? rawVolumePercent
+          : defaults.voiceDucking.volumePercent,
+    };
+
+    // defaultPlatform → an explicit operator default (issue #126). Keep it only
+    // when it names a KNOWN gateable provider that is ALSO currently enabled;
+    // anything else (unknown value, disabled source, wrong type, missing) becomes
+    // null so defaultPlatform() falls back to the fixed priority order.
+    const rawDefault = partial.defaultPlatform;
+    const defaultPlatformPref: GateableProvider | null =
+      typeof rawDefault === "string" &&
+      (GATEABLE_PROVIDERS as readonly string[]).includes(rawDefault) &&
+      enabledProviders.includes(rawDefault as GateableProvider)
+        ? (rawDefault as GateableProvider)
+        : null;
+
+    // audioQuality → per-provider strings; each field falls back to its default
+    // when missing/blank/non-string (a hand-edited/legacy config must never smuggle
+    // a non-string past the gate — the value is fed straight to provider.setQuality).
+    const partialAq = (partial.audioQuality ?? {}) as Partial<AudioQualityConfig>;
+    const coerceQuality = (v: unknown, fallback: string): string =>
+      typeof v === "string" && v.trim() ? v : fallback;
+    const audioQuality: AudioQualityConfig = {
+      netease: coerceQuality(partialAq.netease, defaults.audioQuality.netease),
+      qq: coerceQuality(partialAq.qq, defaults.audioQuality.qq),
+      bilibili: coerceQuality(partialAq.bilibili, defaults.audioQuality.bilibili),
+      kugou: coerceQuality(partialAq.kugou, defaults.audioQuality.kugou),
+      jellyfin: coerceQuality(partialAq.jellyfin, defaults.audioQuality.jellyfin),
+    };
+
     return {
       ...defaults,
       ...partial,
       adminGroups,
       guestMode: gm,
+      spotify,
+      jellyfin,
+      audioQuality,
+      enabledProviders,
+      savedQueuesEnabled,
+      playKeepsQueue,
+      voiceDucking,
+      defaultPlatform: defaultPlatformPref,
     };
-  } catch {
-    return defaults;
   }
 }
 
 export function saveConfig(path: string, config: BotConfig): void {
   mkdirSync(dirname(path), { recursive: true });
-  writeFileSync(path, JSON.stringify(config, null, 2), "utf-8");
+  const json = JSON.stringify(config, null, 2);
+
+  // Atomic write: serialize to a sibling temp file in the SAME directory, then
+  // rename it onto the final path. rename is an atomic replace on POSIX and modern
+  // Windows, so a crash / power loss / ENOSPC mid-write can never leave config.json
+  // truncated — a reader always sees either the previous file or the fully-written
+  // new one, never a partial. The temp lives in the same dir so the rename stays on
+  // one filesystem (a cross-device rename would fail); pid + timestamp keep
+  // concurrent writers from colliding on the temp name.
+  const tmp = `${path}.${process.pid}.${Date.now()}.tmp`;
+  try {
+    writeFileSync(tmp, json, "utf-8");
+    renameSync(tmp, path);
+  } catch (err) {
+    // Never leave a partial temp file behind on failure.
+    try {
+      rmSync(tmp, { force: true });
+    } catch {
+      /* best-effort cleanup */
+    }
+    throw err;
+  }
 }
 
 /**

src/data/database.test.ts

@@ -2,7 +2,7 @@ import { mkdtempSync, rmSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { describe, it, expect, beforeEach, afterEach } from "vitest";
-import { createDatabase, type BotDatabase, type BotInstance, type PlayHistoryEntry } from "./database.js";
+import { createDatabase, SHARED_QUEUE_OWNER, type BotDatabase, type BotInstance, type PlayHistoryEntry } from "./database.js";
 import { createUserStore, GUEST_USER_ID } from "./users.js";
 
 describe("database", () => {
@@ -60,6 +60,7 @@ describe("database", () => {
       album: "Test Album",
       platform: "netease",
       coverUrl: "https://example.com/cover.jpg",
+      requestedBy: "alice",
     });
 
     botDb.addPlayHistory({
@@ -76,6 +77,7 @@ describe("database", () => {
     expect(history).toHaveLength(2);
     expect(history[0].songName).toBe("Another Song");
     expect(history[1].songName).toBe("Test Song");
+    expect(history[1].requestedBy).toBe("alice");
   });
 
   it("saves and loads bot instances", () => {
@@ -129,6 +131,92 @@ describe("database", () => {
     expect(botDb.deleteBotInstance("nonexistent")).toBe(false);
   });
 
+  it("persists and restores per-bot player settings (volume + play mode) (#125)", () => {
+    const inst = {
+      id: "bot-ps",
+      name: "B",
+      serverAddress: "x",
+      serverPort: 9987,
+      nickname: "n",
+      defaultChannel: "",
+      channelId: "",
+      channelPassword: "",
+      autoStart: false,
+      serverProtocol: "",
+      ts6ApiKey: "",
+      serverPassword: "",
+    };
+    botDb.saveBotInstance(inst);
+
+    // Fresh row → in-memory defaults.
+    expect(botDb.getPlayerSettings("bot-ps")).toEqual({ volume: 75, playMode: "seq" });
+
+    // Volume and play mode persist independently.
+    botDb.saveVolume("bot-ps", 42);
+    expect(botDb.getPlayerSettings("bot-ps")).toEqual({ volume: 42, playMode: "seq" });
+    botDb.savePlayMode("bot-ps", "rloop");
+    expect(botDb.getPlayerSettings("bot-ps")).toEqual({ volume: 42, playMode: "rloop" });
+
+    // A later saveBotInstance upsert (e.g. autoStart toggle) must NOT reset them.
+    botDb.saveBotInstance({ ...inst, autoStart: true });
+    expect(botDb.getPlayerSettings("bot-ps")).toEqual({ volume: 42, playMode: "rloop" });
+  });
+
+  it("defaults player settings for an unknown bot and validates inputs (#125)", () => {
+    // No row → defaults.
+    expect(botDb.getPlayerSettings("does-not-exist")).toEqual({ volume: 75, playMode: "seq" });
+
+    botDb.saveBotInstance({
+      id: "bot-v",
+      name: "B",
+      serverAddress: "x",
+      serverPort: 9987,
+      nickname: "n",
+      defaultChannel: "",
+      channelId: "",
+      channelPassword: "",
+      autoStart: false,
+      serverProtocol: "",
+      ts6ApiKey: "",
+      serverPassword: "",
+    });
+    // Out-of-range volume is clamped; an unknown play mode is ignored (not stored).
+    botDb.saveVolume("bot-v", 250);
+    expect(botDb.getPlayerSettings("bot-v").volume).toBe(100);
+    botDb.saveVolume("bot-v", -10);
+    expect(botDb.getPlayerSettings("bot-v").volume).toBe(0);
+    botDb.savePlayMode("bot-v", "bogus");
+    expect(botDb.getPlayerSettings("bot-v").playMode).toBe("seq");
+  });
+
+  it("migrates volume + play_mode columns onto a legacy bot_instances table (#125)", () => {
+    const dir = mkdtempSync(join(tmpdir(), "tsmb-mig-"));
+    const p = join(dir, "legacy.db");
+    // Build a minimal pre-#125 bot_instances table (no volume/play_mode columns).
+    const legacy = createDatabase(p);
+    legacy.db.exec("DROP TABLE bot_instances");
+    legacy.db.exec(`CREATE TABLE bot_instances (
+      id TEXT PRIMARY KEY, name TEXT NOT NULL, serverAddress TEXT NOT NULL,
+      serverPort INTEGER NOT NULL, nickname TEXT NOT NULL, defaultChannel TEXT NOT NULL,
+      channelId TEXT NOT NULL DEFAULT '', channelPassword TEXT NOT NULL,
+      autoStart INTEGER NOT NULL DEFAULT 0, serverProtocol TEXT NOT NULL DEFAULT '',
+      ts6ApiKey TEXT NOT NULL DEFAULT '', serverPassword TEXT NOT NULL DEFAULT '', identity TEXT
+    )`);
+    legacy.db
+      .prepare("INSERT INTO bot_instances (id, name, serverAddress, serverPort, nickname, defaultChannel, channelPassword) VALUES (?, 'B', 'x', 9987, 'n', '', '')")
+      .run("legacy-bot");
+    legacy.close();
+
+    // Reopen → migrateSchema adds the columns; the old row gets the defaults.
+    const reopened = createDatabase(p);
+    const cols = (reopened.db.prepare("PRAGMA table_info(bot_instances)").all() as Array<{ name: string }>).map((c) => c.name);
+    expect(cols).toContain("volume");
+    expect(cols).toContain("play_mode");
+    expect(reopened.getPlayerSettings("legacy-bot")).toEqual({ volume: 75, playMode: "seq" });
+    reopened.close();
+    rmSync(dir, { recursive: true, force: true });
+  });
+
   it("persists and clears customAvatarPath on a bot instance", () => {
     const inst = {
       id: "bot-1",
@@ -151,6 +239,86 @@ describe("database", () => {
     botDb.setCustomAvatarPath("bot-1", null);
     expect(botDb.getCustomAvatarPath("bot-1")).toBeNull();
   });
+
+  const sq = (id: string) => ({
+    id,
+    name: id,
+    artist: "",
+    album: "",
+    platform: "netease" as const,
+    coverUrl: "",
+    duration: 1,
+  });
+
+  describe("saved_queues", () => {
+    it("upserts by (ownerId, name) and returns songs", () => {
+      botDb.saveQueue("u1", "night", [sq("a"), sq("b")]);
+      const again = botDb.saveQueue("u1", "night", [sq("c")]); // overwrite
+      expect(again.songCount).toBe(1);
+      expect(botDb.listSavedQueues("u1", false)).toHaveLength(1);
+      const full = botDb.getSavedQueue(again.id)!;
+      expect(full.songs.map((s) => s.id)).toEqual(["c"]);
+    });
+
+    it("strips url before persisting", () => {
+      const saved = botDb.saveQueue("u1", "x", [
+        { ...sq("a"), url: "http://example.com/a.mp3" } as never,
+      ]);
+      const full = botDb.getSavedQueue(saved.id)!;
+      expect((full.songs[0] as { url?: string }).url).toBeUndefined();
+    });
+
+    it("lists own + shared when includeShared, own-only otherwise", () => {
+      botDb.saveQueue("u1", "mine", [sq("a")]);
+      botDb.saveQueue(SHARED_QUEUE_OWNER, "party", [sq("b")]);
+      expect(botDb.listSavedQueues("u1", false).map((q) => q.name)).toEqual(["mine"]);
+      expect(
+        botDb.listSavedQueues("u1", true).map((q) => q.name).sort(),
+      ).toEqual(["mine", "party"]);
+    });
+
+    it("caps songs at 1000 and queues at 50", () => {
+      expect(() =>
+        botDb.saveQueue("u1", "big", Array.from({ length: 1001 }, (_, i) => sq("s" + i))),
+      ).toThrow(/1000/);
+      for (let i = 0; i < 50; i++) botDb.saveQueue("u1", "q" + i, [sq("a")]);
+      expect(() => botDb.saveQueue("u1", "q50", [sq("a")])).toThrow(/50/);
+      // Overwriting an existing name is always allowed despite the cap.
+      expect(() => botDb.saveQueue("u1", "q0", [sq("z")])).not.toThrow();
+    });
+
+    it("deletes and degrades a corrupt blob to empty", () => {
+      const q = botDb.saveQueue("u1", "x", [sq("a")]);
+      botDb.db.prepare("UPDATE saved_queues SET songs='not json' WHERE id=?").run(q.id);
+      expect(botDb.getSavedQueue(q.id)!.songs).toEqual([]);
+      expect(botDb.deleteSavedQueue(q.id)).toBe(true);
+      expect(botDb.getSavedQueue(q.id)).toBeNull();
+      expect(botDb.deleteSavedQueue(q.id)).toBe(false); // already gone
+    });
+  });
+
+  describe("queue_state", () => {
+    it("upserts, reads back, and clears per bot", () => {
+      botDb.saveQueueState({ botId: "b1", songs: [sq("a")], currentIndex: 0, mode: "loop", isFmMode: true, fmPlatform: "netease" });
+      botDb.saveQueueState({ botId: "b1", songs: [sq("a"), sq("b")], currentIndex: 1, mode: "seq", isFmMode: false, fmPlatform: "" });
+      const st = botDb.getQueueState("b1")!;
+      expect(st.songs.map((s) => s.id)).toEqual(["a", "b"]);
+      expect(st.currentIndex).toBe(1);
+      expect(st.mode).toBe("seq");
+      expect(st.isFmMode).toBe(false);
+      botDb.clearQueueState("b1");
+      expect(botDb.getQueueState("b1")).toBeNull();
+    });
+
+    it("round-trips FM flags and degrades a corrupt blob", () => {
+      botDb.saveQueueState({ botId: "b2", songs: [sq("a")], currentIndex: 0, mode: "random", isFmMode: true, fmPlatform: "qq" });
+      const st = botDb.getQueueState("b2")!;
+      expect(st.isFmMode).toBe(true);
+      expect(st.fmPlatform).toBe("qq");
+      botDb.db.prepare("UPDATE queue_state SET songs='{' WHERE botId=?").run("b2");
+      expect(botDb.getQueueState("b2")!.songs).toEqual([]);
+    });
+  });
 });
 
 describe("guest principal migration", () => {

src/data/database.ts

@@ -1,6 +1,46 @@
 import Database from "better-sqlite3";
 import { CAPABILITIES, BOTS_ALL } from "./permissions.js";
 import { GUEST_USER_ID, GUEST_USERNAME } from "./users.js";
+import type { QueuedSong } from "../audio/queue.js";
+
+/**
+ * Reserved owner id for chat-saved / opt-in-shared queues. A `__`-bracketed
+ * literal can never collide with a real WebUI user id (UUIDs), so it cleanly
+ * partitions "shared" saved queues from per-user private ones (issue #119).
+ */
+export const SHARED_QUEUE_OWNER = "__shared__";
+/** Cap per owner (private user OR the shared bucket). */
+export const MAX_SAVED_QUEUES = 50;
+/** Cap per saved queue / persisted live-queue snapshot. */
+export const MAX_QUEUE_SONGS = 1000;
+
+/** A stored song is a QueuedSong minus the lazily-resolved `url`. */
+export type StoredSong = Omit<QueuedSong, "url">;
+
+/** Saved-queue row without the (potentially large) songs blob — for list views. */
+export interface SavedQueueMeta {
+  id: number;
+  ownerId: string;
+  name: string;
+  songCount: number;
+  createdAt: string;
+  updatedAt: string;
+}
+
+/** Full saved queue, including its songs. */
+export interface SavedQueue extends SavedQueueMeta {
+  songs: StoredSong[];
+}
+
+/** One-row-per-bot persisted live-queue state (Feature 2, auto-restore). */
+export interface QueueStateRow {
+  botId: string;
+  songs: StoredSong[];
+  currentIndex: number;
+  mode: string;
+  isFmMode: boolean;
+  fmPlatform: string;
+}
 
 export interface PlayHistoryEntry {
   botId: string;
@@ -8,8 +48,9 @@ export interface PlayHistoryEntry {
   songName: string;
   artist: string;
   album: string;
-  platform: "netease" | "qq" | "bilibili" | "youtube" | "local";
+  platform: "netease" | "qq" | "bilibili" | "youtube" | "local" | "kugou" | "spotify" | "jellyfin";
   coverUrl: string;
+  requestedBy?: string;
 }
 
 export interface PlayHistoryRecord extends PlayHistoryEntry {
@@ -54,6 +95,26 @@ export const DEFAULT_PROFILE_CONFIG: ProfileConfig = {
   nowPlayingMsgEnabled: true,
 };
 
+/**
+ * Per-bot player settings persisted across restarts (#125): the playback volume
+ * and play mode. These reset to defaults on process restart when kept only in
+ * memory (AudioPlayer/PlayQueue), so they are stored on the bot_instances row —
+ * exactly like the per-bot profile flags — and restored when the bot is (re)built.
+ */
+export interface PlayerSettings {
+  /** 0-100. */
+  volume: number;
+  /** PlayMode string: "seq" | "loop" | "random" | "rloop". */
+  playMode: string;
+}
+
+const PLAY_MODES = new Set(["seq", "loop", "random", "rloop"]);
+
+export const DEFAULT_PLAYER_SETTINGS: PlayerSettings = {
+  volume: 75,
+  playMode: "seq",
+};
+
 export interface FavoritePlaylist {
   id: number;
   userId: string;
@@ -74,12 +135,24 @@ export interface BotDatabase {
   deleteBotInstance(id: string): boolean;
   getProfileConfig(botId: string): ProfileConfig;
   saveProfileConfig(botId: string, config: ProfileConfig): void;
+  getPlayerSettings(botId: string): PlayerSettings;
+  saveVolume(botId: string, volume: number): void;
+  savePlayMode(botId: string, playMode: string): void;
   getCustomAvatarPath(botId: string): string | null;
   setCustomAvatarPath(botId: string, path: string | null): void;
   addFavorite(userId: string, playlist: { platform: string; playlistId: string; name: string; coverUrl: string; songCount: number }): void;
   removeFavorite(userId: string, playlistId: string, platform: string): boolean;
   getFavorites(userId: string): FavoritePlaylist[];
   isFavorited(userId: string, playlistId: string, platform: string): boolean;
+  // Saved queues (Feature 1) — upsert by (ownerId, name), capped.
+  saveQueue(ownerId: string, name: string, songs: StoredSong[]): SavedQueue;
+  listSavedQueues(ownerId: string, includeShared: boolean): SavedQueueMeta[];
+  getSavedQueue(id: number): SavedQueue | null;
+  deleteSavedQueue(id: number): boolean;
+  // Live-queue persistence (Feature 2) — one row per bot.
+  saveQueueState(state: QueueStateRow): void;
+  getQueueState(botId: string): QueueStateRow | null;
+  clearQueueState(botId: string): void;
   close(): void;
 }
 
@@ -118,12 +191,27 @@ function migrateSchema(db: Database.Database): void {
   if (!names.includes("custom_avatar_path")) {
     db.exec("ALTER TABLE bot_instances ADD COLUMN custom_avatar_path TEXT");
   }
+  // Per-bot persisted player settings (#125): volume + play mode. Defaults match
+  // AudioPlayer/PlayQueue's in-memory defaults so pre-existing rows keep behaving
+  // exactly as before until the user changes them.
+  if (!names.includes("volume")) {
+    db.exec("ALTER TABLE bot_instances ADD COLUMN volume INTEGER NOT NULL DEFAULT 75");
+  }
+  if (!names.includes("play_mode")) {
+    db.exec("ALTER TABLE bot_instances ADD COLUMN play_mode TEXT NOT NULL DEFAULT 'seq'");
+  }
 
   const userColumns = db.prepare("PRAGMA table_info(users)").all() as Array<{ name: string }>;
   const userColNames = userColumns.map((c) => c.name);
   if (!userColNames.includes("role")) {
     db.exec("ALTER TABLE users ADD COLUMN role TEXT NOT NULL DEFAULT 'admin'");
   }
+
+  const historyColumns = db.prepare("PRAGMA table_info(play_history)").all() as Array<{ name: string }>;
+  const historyColNames = historyColumns.map((c) => c.name);
+  if (!historyColNames.includes("requestedBy")) {
+    db.exec("ALTER TABLE play_history ADD COLUMN requestedBy TEXT NOT NULL DEFAULT ''");
+  }
 }
 
 function initTables(db: Database.Database): void {
@@ -137,6 +225,7 @@ function initTables(db: Database.Database): void {
       album TEXT NOT NULL,
       platform TEXT NOT NULL,
       coverUrl TEXT NOT NULL,
+      requestedBy TEXT NOT NULL DEFAULT '',
       playedAt TEXT NOT NULL DEFAULT (datetime('now'))
     );
 
@@ -153,6 +242,8 @@ function initTables(db: Database.Database): void {
       serverProtocol TEXT NOT NULL DEFAULT '',
       ts6ApiKey TEXT NOT NULL DEFAULT '',
       serverPassword TEXT NOT NULL DEFAULT '',
+      volume INTEGER NOT NULL DEFAULT 75,
+      play_mode TEXT NOT NULL DEFAULT 'seq',
       identity TEXT
     );
 
@@ -215,6 +306,28 @@ function initTables(db: Database.Database): void {
       FOREIGN KEY (userId) REFERENCES users(id) ON DELETE CASCADE
     );
     CREATE INDEX IF NOT EXISTS idx_user_bot_access_userId ON user_bot_access(userId);
+
+    CREATE TABLE IF NOT EXISTS saved_queues (
+      id        INTEGER PRIMARY KEY AUTOINCREMENT,
+      ownerId   TEXT NOT NULL,
+      name      TEXT NOT NULL,
+      songs     TEXT NOT NULL,
+      songCount INTEGER NOT NULL DEFAULT 0,
+      createdAt TEXT NOT NULL DEFAULT (datetime('now')),
+      updatedAt TEXT NOT NULL DEFAULT (datetime('now')),
+      UNIQUE(ownerId, name)
+    );
+    CREATE INDEX IF NOT EXISTS idx_saved_queues_ownerId ON saved_queues(ownerId);
+
+    CREATE TABLE IF NOT EXISTS queue_state (
+      botId        TEXT PRIMARY KEY,
+      songs        TEXT NOT NULL,
+      currentIndex INTEGER NOT NULL,
+      mode         TEXT NOT NULL,
+      isFmMode     INTEGER NOT NULL DEFAULT 0,
+      fmPlatform   TEXT NOT NULL DEFAULT '',
+      updatedAt    TEXT NOT NULL DEFAULT (datetime('now'))
+    );
   `);
 }
 
@@ -265,8 +378,8 @@ export function createDatabase(dbPath: string): BotDatabase {
   ensureGuestUser(db);
 
   const insertHistory = db.prepare(`
-    INSERT INTO play_history (botId, songId, songName, artist, album, platform, coverUrl)
-    VALUES (@botId, @songId, @songName, @artist, @album, @platform, @coverUrl)
+    INSERT INTO play_history (botId, songId, songName, artist, album, platform, coverUrl, requestedBy)
+    VALUES (@botId, @songId, @songName, @artist, @album, @platform, @coverUrl, @requestedBy)
   `);
 
   const selectHistory = db.prepare(`
@@ -313,6 +426,12 @@ export function createDatabase(dbPath: string): BotDatabase {
     WHERE id = @id
   `);
 
+  const selectPlayerSettings = db.prepare(
+    `SELECT volume, play_mode FROM bot_instances WHERE id = ?`,
+  );
+  const updateVolume = db.prepare(`UPDATE bot_instances SET volume = ? WHERE id = ?`);
+  const updatePlayMode = db.prepare(`UPDATE bot_instances SET play_mode = ? WHERE id = ?`);
+
   const selectCustomAvatar = db.prepare(`SELECT custom_avatar_path FROM bot_instances WHERE id = ?`);
   const updateCustomAvatar = db.prepare(`UPDATE bot_instances SET custom_avatar_path = ? WHERE id = ?`);
 
@@ -334,11 +453,72 @@ export function createDatabase(dbPath: string): BotDatabase {
     SELECT 1 FROM favorite_playlists WHERE userId = ? AND playlistId = ? AND platform = ?
   `);
 
+  // A corrupt/hand-edited songs blob must never throw into a route or the
+  // restore path — degrade to an empty list instead.
+  const parseSongs = (raw: string): StoredSong[] => {
+    try {
+      const v = JSON.parse(raw);
+      return Array.isArray(v) ? (v as StoredSong[]) : [];
+    } catch {
+      return [];
+    }
+  };
+  const rowToSavedMeta = (r: {
+    id: number; ownerId: string; name: string; songCount: number; createdAt: string; updatedAt: string;
+  }): SavedQueueMeta => ({
+    id: r.id,
+    ownerId: r.ownerId,
+    name: r.name,
+    songCount: r.songCount,
+    createdAt: r.createdAt,
+    updatedAt: r.updatedAt,
+  });
+
+  const upsertSavedQueue = db.prepare(`
+    INSERT INTO saved_queues (ownerId, name, songs, songCount)
+    VALUES (@ownerId, @name, @songs, @songCount)
+    ON CONFLICT(ownerId, name) DO UPDATE SET
+      songs = excluded.songs,
+      songCount = excluded.songCount,
+      updatedAt = datetime('now')
+  `);
+  const selectSavedQueueByOwnerName = db.prepare(
+    "SELECT * FROM saved_queues WHERE ownerId = ? AND name = ?",
+  );
+  const selectSavedQueueIdByOwnerName = db.prepare(
+    "SELECT id FROM saved_queues WHERE ownerId = ? AND name = ?",
+  );
+  const countSavedQueues = db.prepare(
+    "SELECT COUNT(*) AS c FROM saved_queues WHERE ownerId = ?",
+  );
+  const listSavedQueuesOwn = db.prepare(
+    "SELECT id, ownerId, name, songCount, createdAt, updatedAt FROM saved_queues WHERE ownerId = ? ORDER BY updatedAt DESC",
+  );
+  const listSavedQueuesShared = db.prepare(
+    "SELECT id, ownerId, name, songCount, createdAt, updatedAt FROM saved_queues WHERE ownerId = ? OR ownerId = ? ORDER BY updatedAt DESC",
+  );
+  const selectSavedQueueById = db.prepare("SELECT * FROM saved_queues WHERE id = ?");
+  const deleteSavedQueueById = db.prepare("DELETE FROM saved_queues WHERE id = ?");
+
+  const upsertQueueState = db.prepare(`
+    INSERT INTO queue_state (botId, songs, currentIndex, mode, isFmMode, fmPlatform, updatedAt)
+    VALUES (@botId, @songs, @currentIndex, @mode, @isFmMode, @fmPlatform, datetime('now'))
+    ON CONFLICT(botId) DO UPDATE SET
+      songs = excluded.songs,
+      currentIndex = excluded.currentIndex,
+      mode = excluded.mode,
+      isFmMode = excluded.isFmMode,
+      fmPlatform = excluded.fmPlatform,
+      updatedAt = datetime('now')
+  `);
+  const selectQueueState = db.prepare("SELECT * FROM queue_state WHERE botId = ?");
+  const deleteQueueState = db.prepare("DELETE FROM queue_state WHERE botId = ?");
+
   return {
     db,
 
     addPlayHistory(record) {
-      insertHistory.run(record);
+      insertHistory.run({ ...record, requestedBy: record.requestedBy ?? "" });
     },
 
     getPlayHistory(botId, limit) {
@@ -398,6 +578,36 @@ export function createDatabase(dbPath: string): BotDatabase {
       });
     },
 
+    getPlayerSettings(botId) {
+      const row = selectPlayerSettings.get(botId) as
+        | { volume: number | null; play_mode: string | null }
+        | undefined;
+      if (!row) return { ...DEFAULT_PLAYER_SETTINGS };
+      // Coerce/validate: clamp volume to 0-100 and fall back to defaults for any
+      // NULL / out-of-range / unknown value (a hand-edited DB must never feed a
+      // bad value into AudioPlayer.setVolume / PlayQueue.setMode).
+      const rawVol = typeof row.volume === "number" ? row.volume : DEFAULT_PLAYER_SETTINGS.volume;
+      const volume = Number.isFinite(rawVol)
+        ? Math.max(0, Math.min(100, Math.round(rawVol)))
+        : DEFAULT_PLAYER_SETTINGS.volume;
+      const playMode =
+        typeof row.play_mode === "string" && PLAY_MODES.has(row.play_mode)
+          ? row.play_mode
+          : DEFAULT_PLAYER_SETTINGS.playMode;
+      return { volume, playMode };
+    },
+
+    saveVolume(botId, volume) {
+      const clamped = Math.max(0, Math.min(100, Math.round(volume)));
+      updateVolume.run(clamped, botId);
+    },
+
+    savePlayMode(botId, playMode) {
+      // Persist only recognized modes so a bad value can never poison the row.
+      if (!PLAY_MODES.has(playMode)) return;
+      updatePlayMode.run(playMode, botId);
+    },
+
     getCustomAvatarPath(botId) {
       const row = selectCustomAvatar.get(botId) as { custom_avatar_path: string | null } | undefined;
       return row?.custom_avatar_path ?? null;
@@ -424,6 +634,85 @@ export function createDatabase(dbPath: string): BotDatabase {
       return row !== undefined;
     },
 
+    saveQueue(ownerId, name, songs) {
+      if (songs.length > MAX_QUEUE_SONGS) {
+        throw new Error(`保存失败：歌曲数量超过上限 ${MAX_QUEUE_SONGS}`);
+      }
+      // Strip any lazily-resolved url before persisting.
+      const stripped: StoredSong[] = songs.map((s) => {
+        const { url: _url, ...rest } = s as QueuedSong;
+        return rest;
+      });
+      // Enforce the per-owner cap only for a NEW name (an overwrite of an
+      // existing saved queue must always be allowed).
+      const existing = selectSavedQueueIdByOwnerName.get(ownerId, name) as
+        | { id: number }
+        | undefined;
+      if (!existing) {
+        const { c } = countSavedQueues.get(ownerId) as { c: number };
+        if (c >= MAX_SAVED_QUEUES) {
+          throw new Error(`保存失败：已保存队列数量超过上限 ${MAX_SAVED_QUEUES}`);
+        }
+      }
+      upsertSavedQueue.run({
+        ownerId,
+        name,
+        songs: JSON.stringify(stripped),
+        songCount: stripped.length,
+      });
+      const row = selectSavedQueueByOwnerName.get(ownerId, name) as SavedQueueMeta;
+      return { ...rowToSavedMeta(row), songs: stripped };
+    },
+
+    listSavedQueues(ownerId, includeShared) {
+      const rows = includeShared
+        ? (listSavedQueuesShared.all(ownerId, SHARED_QUEUE_OWNER) as SavedQueueMeta[])
+        : (listSavedQueuesOwn.all(ownerId) as SavedQueueMeta[]);
+      return rows.map(rowToSavedMeta);
+    },
+
+    getSavedQueue(id) {
+      const row = selectSavedQueueById.get(id) as
+        | (SavedQueueMeta & { songs: string })
+        | undefined;
+      if (!row) return null;
+      return { ...rowToSavedMeta(row), songs: parseSongs(row.songs) };
+    },
+
+    deleteSavedQueue(id) {
+      return deleteSavedQueueById.run(id).changes > 0;
+    },
+
+    saveQueueState(state) {
+      upsertQueueState.run({
+        botId: state.botId,
+        songs: JSON.stringify(state.songs),
+        currentIndex: state.currentIndex,
+        mode: state.mode,
+        isFmMode: state.isFmMode ? 1 : 0,
+        fmPlatform: state.fmPlatform,
+      });
+    },
+
+    getQueueState(botId) {
+      const r = selectQueueState.get(botId) as
+        | { botId: string; songs: string; currentIndex: number; mode: string; isFmMode: number; fmPlatform: string }
+        | undefined;
+      if (!r) return null;
+      return {
+        botId: r.botId,
+        songs: parseSongs(r.songs),
+        currentIndex: r.currentIndex,
+        mode: r.mode,
+        isFmMode: r.isFmMode === 1,
+        fmPlatform: r.fmPlatform,
+      };
+    },
+
+    clearQueueState(botId) {
+      deleteQueueState.run(botId);
+    },
+
     close() {
       db.close();
     },

src/index.ts

@@ -1,6 +1,6 @@
 import path from "node:path";
 import { fileURLToPath } from "node:url";
-import { loadConfig, saveConfig, migrateLegacyConfig } from "./data/config.js";
+import { loadConfig, saveConfig, migrateLegacyConfig, isProviderEnabled } from "./data/config.js";
 import { createDatabase } from "./data/database.js";
 import { createLogger } from "./logger.js";
 import { createApiServerManager } from "./music/api-server.js";
@@ -8,6 +8,10 @@ import { NeteaseProvider } from "./music/netease.js";
 import { QQMusicProvider } from "./music/qq.js";
 import { BiliBiliProvider } from "./music/bilibili.js";
 import { LocalMusicProvider } from "./music/local.js";
+import { KugouProvider } from "./music/kugou.js";
+import { JellyfinProvider } from "./music/jellyfin.js";
+import { SpotifyProvider } from "./music/spotify/provider.js";
+import { SpotifyOAuth, createFileOAuthTokenStore } from "./music/spotify/spotify-oauth.js";
 import { createCookieStore } from "./music/auth.js";
 import { createAvatarStore } from "./data/avatars.js";
 import { createPermissionStore } from "./data/permissions.js";
@@ -27,6 +31,7 @@ const LOG_DIR = path.join(DATA_DIR, "logs");
 const COOKIE_DIR = path.join(DATA_DIR, "cookies");
 const AVATAR_DIR = path.join(DATA_DIR, "avatars");
 const LOCAL_AUDIO_DIR = path.join(DATA_DIR, "local-audio");
+const SPOTIFY_DATA_DIR = path.join(DATA_DIR, "spotify");
 const STATIC_DIR = path.join(ROOT_DIR, "web", "dist");
 
 async function main() {
@@ -48,7 +53,14 @@ async function main() {
   const db = createDatabase(DB_PATH);
 
   const apiServer = createApiServerManager(
-    { neteasePort: config.neteaseApiPort, qqMusicPort: config.qqMusicApiPort },
+    {
+      neteasePort: config.neteaseApiPort,
+      qqMusicPort: config.qqMusicApiPort,
+      // Provider gating: a sidecar only starts (and binds 3001/3200) when its
+      // source is listed in enabledProviders — both are on in the default config.
+      neteaseEnabled: isProviderEnabled(config, "netease"),
+      qqEnabled: isProviderEnabled(config, "qq"),
+    },
     logger
   );
   await apiServer.start();
@@ -57,6 +69,15 @@ async function main() {
   const qqProvider = new QQMusicProvider(apiServer.getQQMusicBaseUrl());
   const bilibiliProvider = new BiliBiliProvider();
   const localProvider = new LocalMusicProvider(LOCAL_AUDIO_DIR);
+  const kugouProvider = new KugouProvider();
+  const spotifyProvider = new SpotifyProvider();
+  // Safety gate (spec §7): the source is inert unless EXPLICITLY enabled.
+  // Only feed credentials when enabled — otherwise the provider has no creds,
+  // hasCreds() is false, search returns empty, and getAuthStatus() is loggedIn:false,
+  // so setting a Client ID/Secret alone (enabled:false) never activates Spotify.
+  if (config.spotify.enabled && config.spotify.clientId) {
+    spotifyProvider.setCreds(config.spotify.clientId, config.spotify.clientSecret);
+  }
 
   const cookieStore = createCookieStore(COOKIE_DIR);
   const avatarStore = createAvatarStore(AVATAR_DIR);
@@ -66,9 +87,46 @@ async function main() {
   if (qqCookie) qqProvider.setCookie(qqCookie);
   const bilibiliCookie = cookieStore.load("bilibili");
   if (bilibiliCookie) bilibiliProvider.setCookie(bilibiliCookie);
+  const kugouCookie = cookieStore.load("kugou");
+  if (kugouCookie) kugouProvider.setCookie(kugouCookie);
+
+  // Jellyfin: admin-configured connection (no QR). The persisted blob carries
+  // AccessToken + User.Id + DeviceId and lives alongside the other platform
+  // cookies; a Jellyfin server that is unreachable at boot must not block
+  // startup — the provider authenticates lazily on first use.
+  const jellyfinProvider = new JellyfinProvider(logger);
+  jellyfinProvider.configure(config.jellyfin);
+  const jellyfinAuth = cookieStore.load("jellyfin");
+  if (jellyfinAuth) jellyfinProvider.setCookie(jellyfinAuth);
+  jellyfinProvider.setPersist((serialized) => cookieStore.save("jellyfin", serialized));
+
+  // Restore the persisted per-provider audio quality (#125) onto the shared,
+  // process-wide providers so a restart keeps the user's choice. setQuality()
+  // normalizes/ignores unknown values, so a stale entry can never break playback.
+  neteaseProvider.setQuality(config.audioQuality.netease);
+  qqProvider.setQuality(config.audioQuality.qq);
+  bilibiliProvider.setQuality(config.audioQuality.bilibili);
+  kugouProvider.setQuality(config.audioQuality.kugou);
+  jellyfinProvider.setQuality(config.audioQuality.jellyfin);
 
   const permissions = createPermissionStore(db.db);
 
+  // Single process-wide Spotify authorization (one Premium account for Stage 3).
+  // Threaded into BOTH the web OAuth router and every bot's SpotifyController so
+  // a web login immediately authorizes playback (C3.1). Own-app clientId => the
+  // redirect points at this bot's web callback; empty clientId leaves OAuth
+  // disabled (isAuthorized() stays false and the Rust backend never starts).
+  const spotifyOAuthClientId = config.spotify.clientId.trim();
+  const spotifyOAuth = new SpotifyOAuth({
+    clientId: spotifyOAuthClientId || undefined,
+    redirectUri: spotifyOAuthClientId
+      ? `http://127.0.0.1:${config.webPort}/api/spotify/callback`
+      : undefined,
+    store: createFileOAuthTokenStore(
+      path.join(SPOTIFY_DATA_DIR, "oauth", "oauth-tokens.json"),
+    ),
+  });
+
   const botManager = new BotManager(
     neteaseProvider,
     qqProvider,
@@ -79,7 +137,12 @@ async function main() {
     avatarStore,
     permissions,
     CONFIG_PATH,
-    localProvider
+    localProvider,
+    kugouProvider,
+    spotifyProvider,
+    SPOTIFY_DATA_DIR,
+    spotifyOAuth,
+    jellyfinProvider
   );
   await botManager.loadSavedBots();
 
@@ -90,6 +153,9 @@ async function main() {
     qqProvider,
     bilibiliProvider,
     localProvider,
+    kugouProvider,
+    spotifyProvider,
+    jellyfinProvider,
     database: db,
     avatarStore,
     config,
@@ -97,6 +163,7 @@ async function main() {
     logger,
     cookieStore,
     staticDir: STATIC_DIR,
+    spotifyOAuth,
   });
   await webServer.start();
 

src/music/api-server.test.ts

@@ -0,0 +1,133 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { createApiServerManager, describeQqApiStartupError } from "./api-server.js";
+import type { Logger } from "../logger.js";
+
+// Record every listen() the QQ sidecar makes so we can assert it is always
+// pinned to the configured port (regression coverage for issue #122).
+const mockState = vi.hoisted(() => ({
+  listenCalls: [] as Array<{ port: number; host: string }>,
+}));
+
+vi.mock("@sansenjian/qq-music-api", () => {
+  const app = {
+    listen(port: number, host: string, cb?: () => void) {
+      mockState.listenCalls.push({ port, host });
+      const server = {
+        address: () => ({ port, address: host, family: "IPv4" as const }),
+        on() {
+          return server;
+        },
+        close(done?: () => void) {
+          done?.();
+        },
+      };
+      // Real net/Koa fire the listening callback on a later tick, after the
+      // caller has captured the returned server handle.
+      if (cb) setImmediate(cb);
+      return server;
+    },
+  };
+  return { default: app };
+});
+
+describe("describeQqApiStartupError", () => {
+  it("flags ERR_REQUIRE_ESM by error code with version-pin guidance", () => {
+    const hint = describeQqApiStartupError({ code: "ERR_REQUIRE_ESM", message: "..." });
+    expect(hint).toMatch(/ERR_REQUIRE_ESM/);
+    expect(hint).toMatch(/~2\.4\.0/);
+    expect(hint).toMatch(/~2\.2\.10/);
+  });
+
+  it("flags ERR_REQUIRE_ESM by message when the code is absent", () => {
+    const hint = describeQqApiStartupError(
+      new Error("require() of ES Module .../@sansenjian/qq-music-api/dist/index.js not supported")
+    );
+    expect(hint).toMatch(/incompatible @sansenjian\/qq-music-api/);
+  });
+
+  it("flags a Node engine mismatch with a Node-upgrade hint", () => {
+    const hint = describeQqApiStartupError(new Error("Unsupported engine: requires Node >=20.17"));
+    expect(hint).toMatch(/Node >=20\.17/);
+    expect(hint).toMatch(/~2\.2\.10/);
+  });
+
+  it("returns null for an unrelated startup error (falls back to the generic warning)", () => {
+    expect(describeQqApiStartupError(new Error("EADDRINUSE: port in use"))).toBeNull();
+    expect(describeQqApiStartupError(undefined)).toBeNull();
+    expect(describeQqApiStartupError(null)).toBeNull();
+  });
+});
+
+// Regression coverage for issue #122: the QQ Music API sidecar must listen on
+// the same port the client base URL targets (config.qqMusicApiPort). A stale
+// build once bound 3300 while the client requested 3200, silently breaking the
+// QQ login QR / search flow with ECONNREFUSED on 127.0.0.1:3200.
+describe("createApiServerManager — QQ sidecar port binding", () => {
+  const noopLogger = {
+    info() {},
+    warn() {},
+    error() {},
+    debug() {},
+    trace() {},
+    fatal() {},
+  } as unknown as Logger;
+
+  beforeEach(() => {
+    mockState.listenCalls = [];
+  });
+
+  it("listens on the configured qqMusicPort and exposes a matching base URL", async () => {
+    const port = 39217; // uncommon port to avoid clashing with a real instance
+    const manager = createApiServerManager(
+      { neteasePort: 39218, qqMusicPort: port, neteaseEnabled: false, qqEnabled: true },
+      noopLogger
+    );
+    await manager.start();
+    manager.stop();
+
+    expect(manager.getQQMusicBaseUrl()).toBe(`http://127.0.0.1:${port}`);
+    expect(mockState.listenCalls).toEqual([{ port, host: "127.0.0.1" }]);
+  });
+
+  it("follows qqMusicPort — not an injected PORT — and restores PORT afterwards", async () => {
+    const port = 39219;
+    const previous = process.env.PORT;
+    // Simulate a hosting platform / compose file injecting a stray PORT that
+    // must NOT leak into the QQ sidecar's chosen port.
+    process.env.PORT = "39999";
+    const manager = createApiServerManager(
+      { neteasePort: 39220, qqMusicPort: port, neteaseEnabled: false, qqEnabled: true },
+      noopLogger
+    );
+    try {
+      await manager.start();
+      // The sidecar follows qqMusicPort, never the injected PORT.
+      expect(mockState.listenCalls).toEqual([{ port, host: "127.0.0.1" }]);
+      // The injected PORT is restored so nothing else in the process is affected.
+      expect(process.env.PORT).toBe("39999");
+    } finally {
+      manager.stop();
+      if (previous === undefined) delete process.env.PORT;
+      else process.env.PORT = previous;
+    }
+  });
+
+  it("leaves an absent PORT env unset after importing the sidecar", async () => {
+    const port = 39221;
+    const previous = process.env.PORT;
+    delete process.env.PORT;
+    const manager = createApiServerManager(
+      { neteasePort: 39222, qqMusicPort: port, neteaseEnabled: false, qqEnabled: true },
+      noopLogger
+    );
+    try {
+      await manager.start();
+      // Was unset before importing — must be unset again, no leaked override.
+      expect(process.env.PORT).toBeUndefined();
+    } finally {
+      manager.stop();
+      if (previous === undefined) delete process.env.PORT;
+      else process.env.PORT = previous;
+    }
+  });
+});

src/music/api-server.ts

@@ -5,6 +5,10 @@ import type { Server } from "node:http";
 export interface ApiServerOptions {
   neteasePort: number;
   qqMusicPort: number;
+  /** Provider gating (#enabledProviders): when false, the corresponding
+   *  embedded sidecar API server is never started and its port never bound. */
+  neteaseEnabled?: boolean;
+  qqEnabled?: boolean;
 }
 
 export interface ApiServerManager {
@@ -14,6 +18,32 @@ export interface ApiServerManager {
   getQQMusicBaseUrl(): string;
 }
 
+/**
+ * Classify a QQ Music API (@sansenjian/qq-music-api) startup failure into
+ * actionable operator guidance, or null when it isn't a recognised
+ * dependency/runtime mismatch. Exported for testing.
+ *
+ * Background: the package became ESM in 2.3.x. A loose `^` range could pull an
+ * ESM-only build (2.3.0/2.3.1) that throws ERR_REQUIRE_ESM, or a 2.4.x build
+ * that needs Node >=20.17 — either way the embedded server never binds, so
+ * every QQ request fails downstream with ECONNREFUSED on the API port.
+ */
+export function describeQqApiStartupError(err: unknown): string | null {
+  const e = (err ?? {}) as { code?: string; message?: string };
+  const code = String(e.code ?? "");
+  const msg = String(e.message ?? "");
+  if (code === "ERR_REQUIRE_ESM" || /ERR_REQUIRE_ESM|require\(\) of ES ?Module/i.test(msg)) {
+    return (
+      "an incompatible @sansenjian/qq-music-api build is installed (ERR_REQUIRE_ESM). " +
+      "Pin it to ~2.4.0 (needs Node >=20.17) or ~2.2.10 in package.json, then reinstall"
+    );
+  }
+  if (/Unsupported engine|EBADENGINE|requires Node|Node\.js version/i.test(msg)) {
+    return "@sansenjian/qq-music-api 2.4.x requires Node >=20.17 (or >=22.9) — upgrade Node, or pin the package to ~2.2.10";
+  }
+  return null;
+}
+
 function isPortFree(port: number): Promise<boolean> {
   return new Promise((resolve) => {
     const server = net.createServer();
@@ -39,34 +69,43 @@ export function createApiServerManager(
 
   return {
     async start(): Promise<void> {
+      // Provider gating: with the jellyfin-only default config neither legacy
+      // sidecar starts, so ports 3001/3200 are never opened.
+      if (options.neteaseEnabled === false && options.qqEnabled === false) {
+        logger.info("NetEase/QQ providers disabled — embedded music API servers not started");
+        return;
+      }
       logger.info("Starting embedded music API servers...");
 
       // Start NetEase Cloud Music API
-      try {
-        const portFree = await isPortFree(options.neteasePort);
-        if (!portFree) {
-          logger.info(
-            { port: options.neteasePort },
-            "NetEase API port already in use — reusing existing instance"
-          );
-        } else {
-          const ncmModule = await import("NeteaseCloudMusicApi") as any;
-          const serverObj = ncmModule.server ?? ncmModule.default?.server;
-          const app = await serverObj.serveNcmApi({ port: options.neteasePort });
-          neteaseServer = app;
-          logger.info(
-            { port: options.neteasePort },
-            "NetEase Cloud Music API started"
-          );
+      if (options.neteaseEnabled !== false) {
+        try {
+          const portFree = await isPortFree(options.neteasePort);
+          if (!portFree) {
+            logger.info(
+              { port: options.neteasePort },
+              "NetEase API port already in use — reusing existing instance"
+            );
+          } else {
+            const ncmModule = await import("NeteaseCloudMusicApi") as any;
+            const serverObj = ncmModule.server ?? ncmModule.default?.server;
+            const app = await serverObj.serveNcmApi({ port: options.neteasePort });
+            neteaseServer = app;
+            logger.info(
+              { port: options.neteasePort },
+              "NetEase Cloud Music API started"
+            );
+          }
+        } catch (err) {
+          logger.error({ err }, "Failed to start NetEase Cloud Music API");
         }
-      } catch (err) {
-        logger.error({ err }, "Failed to start NetEase Cloud Music API");
       }
 
       // Start QQ Music API. Older versions auto-started on import; the
       // current fork (2.2.11+) only listens when run as `require.main`,
       // so we explicitly call .listen() on the imported Koa app and keep
       // the server handle for clean shutdown.
+      if (options.qqEnabled === false) return;
       try {
         const portFree = await isPortFree(options.qqMusicPort);
         if (!portFree) {
@@ -75,7 +114,25 @@ export function createApiServerManager(
             "QQ Music API port already in use — reusing existing instance"
           );
         } else {
-          const qqModule = (await import("@sansenjian/qq-music-api")) as any;
+          // Pin the upstream server to the configured port before importing.
+          // The package derives its default port from process.env.PORT (falling
+          // back to 3200) and, in some historical versions, auto-started that
+          // server as an import side effect. Aligning PORT with qqMusicApiPort
+          // guarantees the sidecar can never bind a different port than the one
+          // the client base URL (getQQMusicBaseUrl) targets — the root cause of
+          // issue #122, where an old build listened on 3300 while the client
+          // requested 3200. Restore the previous value right after import so we
+          // never leak the override into the rest of the process (e.g. the web
+          // server or the NetEase sidecar, which also read PORT as a fallback).
+          const prevPortEnv = process.env.PORT;
+          process.env.PORT = String(options.qqMusicPort);
+          let qqModule: any;
+          try {
+            qqModule = (await import("@sansenjian/qq-music-api")) as any;
+          } finally {
+            if (prevPortEnv === undefined) delete process.env.PORT;
+            else process.env.PORT = prevPortEnv;
+          }
           // The module's export structure varies between versions:
           //   2.2.11+: default → Koa app (has .listen)
           //   2.2.10:  default → wrapper object whose .default is the Koa app
@@ -85,25 +142,51 @@ export function createApiServerManager(
             ? candidate
             : candidate.default ?? null;
           if (koaApp && typeof koaApp.listen === "function") {
-            qqMusicServer = await new Promise<Server>((resolve, reject) => {
-              const srv = koaApp.listen(options.qqMusicPort, "127.0.0.1", () =>
-                resolve(srv)
+            // A version that auto-started on import has already bound the
+            // configured port (thanks to the PORT alignment above); reuse it
+            // rather than racing a second listen that would fail EADDRINUSE.
+            const stillFree = await isPortFree(options.qqMusicPort);
+            if (!stillFree) {
+              logger.info(
+                { port: options.qqMusicPort },
+                "QQ Music API already listening on the configured port (auto-started on import) — reusing embedded instance"
               );
-              srv.on("error", reject);
-            });
-            logger.info(
-              { port: options.qqMusicPort },
-              "QQ Music API started"
-            );
+            } else {
+              qqMusicServer = await new Promise<Server>((resolve, reject) => {
+                const srv = koaApp.listen(options.qqMusicPort, "127.0.0.1", () =>
+                  resolve(srv)
+                );
+                srv.on("error", reject);
+              });
+              // Log the port actually bound (read from the socket) rather than
+              // the requested one, so operators can spot a mismatch in the logs.
+              const addr = qqMusicServer.address();
+              const boundPort =
+                addr && typeof addr === "object" && addr !== null
+                  ? addr.port
+                  : options.qqMusicPort;
+              logger.info(
+                { port: boundPort },
+                "QQ Music API started"
+              );
+            }
           } else {
             logger.warn("QQ Music API module does not expose a Koa app");
           }
         }
       } catch (err) {
-        logger.warn(
-          { err },
-          "QQ Music API not available — QQ Music features may be limited"
-        );
+        const hint = describeQqApiStartupError(err);
+        if (hint) {
+          logger.error(
+            { err },
+            `QQ Music API failed to start — ${hint}. QQ features (search/play/login) will be unavailable until fixed; port ${options.qqMusicPort} is down.`
+          );
+        } else {
+          logger.warn(
+            { err },
+            "QQ Music API not available — QQ Music features may be limited"
+          );
+        }
       }
     },
 

src/music/auth.ts

@@ -1,9 +1,13 @@
 import fs from "node:fs";
 import path from "node:path";
 
+/** Platforms with a persisted credential blob. For jellyfin the "cookie" is a
+ *  JSON string carrying the access token / userId / deviceId (see jellyfin.ts). */
+type CookiePlatform = "netease" | "qq" | "bilibili" | "kugou" | "jellyfin";
+
 export interface CookieStore {
-  save(platform: "netease" | "qq" | "bilibili", cookie: string): void;
-  load(platform: "netease" | "qq" | "bilibili"): string;
+  save(platform: CookiePlatform, cookie: string): void;
+  load(platform: CookiePlatform): string;
 }
 
 export function createCookieStore(cookieDir: string): CookieStore {
@@ -12,7 +16,7 @@ export function createCookieStore(cookieDir: string): CookieStore {
   }
 
   return {
-    save(platform: "netease" | "qq" | "bilibili", cookie: string): void {
+    save(platform: CookiePlatform, cookie: string): void {
       const filePath = path.join(cookieDir, `${platform}.json`);
       fs.writeFileSync(
         filePath,
@@ -21,7 +25,7 @@ export function createCookieStore(cookieDir: string): CookieStore {
       );
     },
 
-    load(platform: "netease" | "qq" | "bilibili"): string {
+    load(platform: CookiePlatform): string {
       const filePath = path.join(cookieDir, `${platform}.json`);
       if (!fs.existsSync(filePath)) return "";
       try {

src/music/bilibili.test.ts

@@ -0,0 +1,164 @@
+import { describe, it, expect, vi } from "vitest";
+import { BiliBiliProvider } from "./bilibili.js";
+
+describe("BiliBiliProvider.search pagination", () => {
+  function mockProvider() {
+    const p = new BiliBiliProvider();
+    const get = vi.fn().mockResolvedValue({ data: { data: { result: [] } } });
+    // Short-circuit the buvid + wbi bootstrap so search only issues the
+    // /search/type request we want to inspect.
+    (p as any).buvidInitialized = true;
+    (p as any).wbiMixinKey = "0".repeat(32);
+    (p as any).wbiKeyFetchedAt = Date.now();
+    (p as any).api = { get };
+    return { p, get };
+  }
+
+  function searchParams(get: ReturnType<typeof vi.fn>) {
+    const call = get.mock.calls.find(
+      (c: any[]) => c[0] === "/x/web-interface/wbi/search/type"
+    );
+    expect(call, "expected a /search/type call").toBeTruthy();
+    // signWbi stringifies every value.
+    return call![1].params as Record<string, string>;
+  }
+
+  it("adds page (offset/limit+1) alongside page_size", async () => {
+    const { p, get } = mockProvider();
+    await p.search("hello", 20, 20); // page 2
+    const params = searchParams(get);
+    expect(params.page).toBe("2");
+    expect(params.page_size).toBe("20");
+  });
+
+  it("defaults offset to 0 → page 1 (backward compatible)", async () => {
+    const { p, get } = mockProvider();
+    await p.search("hello", 20);
+    expect(searchParams(get).page).toBe("1");
+  });
+});
+
+describe("BiliBiliProvider multi-P support", () => {
+  it("parseBilibiliId extracts bvid and page correctly", async () => {
+    const { parseBilibiliId } = await import("./bilibili.js");
+    expect(parseBilibiliId("BV1yxHQeYEuE")).toEqual({ bvid: "BV1yxHQeYEuE", page: 1 });
+    expect(parseBilibiliId("BV1yxHQeYEuE?p=3")).toEqual({ bvid: "BV1yxHQeYEuE", page: 3 });
+    expect(parseBilibiliId("BV1yxHQeYEuE:p2")).toEqual({ bvid: "BV1yxHQeYEuE", page: 2 });
+    expect(parseBilibiliId("https://www.bilibili.com/video/BV1yxHQeYEuE?p=5")).toEqual({
+      bvid: "BV1yxHQeYEuE",
+      page: 5,
+    });
+    expect(parseBilibiliId("some-other-id")).toEqual({ bvid: "some-other-id", page: 1 });
+  });
+
+  function mockViewProvider(viewData: any, playUrlData?: any) {
+    const p = new BiliBiliProvider();
+    const get = vi.fn().mockImplementation((url: string, opts?: any) => {
+      if (url === "/x/web-interface/view") {
+        return Promise.resolve({ data: { data: viewData } });
+      }
+      if (url === "/x/player/playurl") {
+        return Promise.resolve({ data: { data: playUrlData ?? {} } });
+      }
+      return Promise.resolve({ data: {} });
+    });
+    (p as any).buvidInitialized = true;
+    (p as any).api = { get };
+    return { p, get };
+  }
+
+  const multiPViewData = {
+    bvid: "BV1multiP",
+    title: "测试多P教程",
+    pic: "http://i0.hdslb.com/bfs/archive/test.jpg",
+    duration: 300, // 总时长 300 秒 (120 + 180)
+    owner: { name: "UP主测试" },
+    pages: [
+      { cid: 10001, page: 1, part: "第一讲 入门", duration: 120 },
+      { cid: 10002, page: 2, part: "第二讲 进阶", duration: 180 },
+    ],
+  };
+
+  const singlePViewData = {
+    bvid: "BV1singleP",
+    title: "测试单P视频",
+    pic: "http://i0.hdslb.com/bfs/archive/single.jpg",
+    duration: 200,
+    owner: { name: "UP主测试" },
+    pages: [
+      { cid: 20001, page: 1, part: "测试单P视频", duration: 200 },
+    ],
+  };
+
+  it("getSongDetail for single-P video returns total duration and clean bvid", async () => {
+    const { p } = mockViewProvider(singlePViewData);
+    const song = await p.getSongDetail("BV1singleP");
+    expect(song).not.toBeNull();
+    expect(song!.id).toBe("BV1singleP");
+    expect(song!.name).toBe("测试单P视频");
+    expect(song!.duration).toBe(200);
+    expect(song!.platform).toBe("bilibili");
+  });
+
+  it("getSongDetail for multi-P video without ?p defaults to P1 with P1 duration", async () => {
+    const { p } = mockViewProvider(multiPViewData);
+    const song = await p.getSongDetail("BV1multiP");
+    expect(song).not.toBeNull();
+    expect(song!.id).toBe("BV1multiP?p=1");
+    expect(song!.name).toBe("测试多P教程 - P1 第一讲 入门");
+    expect(song!.duration).toBe(120); // P1 独立时长，而非总时长 300！
+    expect(song!.platform).toBe("bilibili");
+  });
+
+  it("getSongDetail for multi-P video with ?p=2 returns P2 with P2 duration", async () => {
+    const { p } = mockViewProvider(multiPViewData);
+    const song = await p.getSongDetail("BV1multiP?p=2");
+    expect(song).not.toBeNull();
+    expect(song!.id).toBe("BV1multiP?p=2");
+    expect(song!.name).toBe("测试多P教程 - P2 第二讲 进阶");
+    expect(song!.duration).toBe(180); // P2 独立时长
+    expect(song!.platform).toBe("bilibili");
+  });
+
+  it("getVideoParts returns all parts with duration and cid", async () => {
+    const { p } = mockViewProvider(multiPViewData);
+    const partsResult = await p.getVideoParts("BV1multiP");
+    expect(partsResult).not.toBeNull();
+    expect(partsResult!.bvid).toBe("BV1multiP");
+    expect(partsResult!.title).toBe("测试多P教程");
+    expect(partsResult!.parts).toHaveLength(2);
+    expect(partsResult!.parts[0]).toEqual({
+      part: 1,
+      cid: 10001,
+      title: "第一讲 入门",
+      duration: 120,
+    });
+    expect(partsResult!.parts[1]).toEqual({
+      part: 2,
+      cid: 10002,
+      title: "第二讲 进阶",
+      duration: 180,
+    });
+  });
+
+  it("getSongUrl requests playurl with correct cid for specific part", async () => {
+    const playUrlResponse = {
+      dash: {
+        audio: [
+          { bandwidth: 64000, baseUrl: "http://audio.64k.test" },
+          { bandwidth: 320000, baseUrl: "http://audio.320k.test" },
+        ],
+      },
+    };
+    const { p, get } = mockViewProvider(multiPViewData, playUrlResponse);
+
+    const result = await p.getSongUrl("BV1multiP?p=2");
+    expect(result).not.toBeNull();
+    expect(result!.url).toBe("http://audio.320k.test");
+
+    const playurlCall = get.mock.calls.find((c: any[]) => c[0] === "/x/player/playurl");
+    expect(playurlCall).toBeTruthy();
+    expect(playurlCall![1].params.cid).toBe(10002); // 准确传入 P2 的 cid
+    expect(playurlCall![1].params.bvid).toBe("BV1multiP"); // 纯净 bvid
+  });
+});

src/music/bilibili.ts

@@ -27,6 +27,38 @@ const WBI_MIXIN_KEY_ENC_TAB = [
 
 const WBI_KEY_TTL_MS = 6 * 60 * 60 * 1000; // wbi keys rotate ~daily; refresh every 6h
 
+export interface BiliVideoPart {
+  part: number;
+  cid: number;
+  title: string;
+  duration: number;
+}
+
+export interface BiliVideoPartsResult {
+  bvid: string;
+  title: string;
+  coverUrl: string;
+  artist: string;
+  parts: BiliVideoPart[];
+}
+
+/**
+ * 解析带有分P信息的 B站 ID 或 URL。
+ * 支持形如 "BVxxxx", "BVxxxx?p=2", "BVxxxx:p2" 以及完整 URL 等格式，默认 page 为 1。
+ */
+export function parseBilibiliId(songId: string): { bvid: string; page: number } {
+  const str = (songId ?? "").trim();
+  const bvMatch = str.match(/BV[0-9A-Za-z]+/i);
+  if (!bvMatch) {
+    return { bvid: str, page: 1 };
+  }
+  const bvid = bvMatch[0];
+  const pageMatch = str.match(/[?&]p=(\d+)|:p?(\d+)/i);
+  const pageStr = pageMatch ? (pageMatch[1] ?? pageMatch[2]) : undefined;
+  const page = pageStr ? parseInt(pageStr, 10) : 1;
+  return { bvid, page: Math.max(1, page) };
+}
+
 export class BiliBiliProvider implements MusicProvider {
   readonly platform = "bilibili" as const;
   private api: AxiosInstance;
@@ -147,12 +179,16 @@ export class BiliBiliProvider implements MusicProvider {
     return fixed;
   }
 
-  async search(query: string, limit = 20): Promise<SearchResult> {
+  async search(query: string, limit = 20, offset = 0): Promise<SearchResult> {
     await this.ensureBuvidCookie();
     await this.ensureWbiKeys();
+    // /search/type is page-based; the web pages in limit-aligned steps so
+    // offset is a multiple of page_size.
+    const page = Math.floor(offset / limit) + 1;
     const signed = this.signWbi({
       search_type: "video",
       keyword: query,
+      page,
       page_size: limit,
     });
     const res = await this.api.get("/x/web-interface/wbi/search/type", {
@@ -188,18 +224,41 @@ export class BiliBiliProvider implements MusicProvider {
   }
 
   async getSongDetail(songId: string): Promise<Song | null> {
+    const { bvid, page } = parseBilibiliId(songId);
     try {
       const res = await this.api.get("/x/web-interface/view", {
-        params: { bvid: songId },
+        params: { bvid },
         headers: this.cookieHeaders,
       });
 
       const data = res.data?.data;
       if (!data) return null;
 
-      // Cache cid for later audio URL fetching
-      if (data.pages?.[0]?.cid) {
-        this.cidCache.set(songId, data.pages[0].cid);
+      const pages = data.pages ?? [];
+      // 缓存所有分P的 cid 映射
+      for (const p of pages) {
+        this.cidCache.set(`${bvid}?p=${p.page}`, p.cid);
+      }
+      if (pages[0]?.cid) {
+        this.cidCache.set(bvid, pages[0].cid);
+      }
+
+      const targetPage = pages.find((p: any) => p.page === page) ?? pages[0];
+
+      // 若为多P视频，返回对应分P的名称与独立时长
+      if (pages.length > 1 && targetPage) {
+        const partTitle = targetPage.part && targetPage.part !== data.title
+          ? `${data.title} - P${targetPage.page} ${targetPage.part}`
+          : `${data.title} (P${targetPage.page})`;
+        return {
+          id: `${bvid}?p=${targetPage.page}`,
+          name: partTitle,
+          artist: data.owner?.name ?? "",
+          album: "",
+          duration: targetPage.duration ?? 0,
+          coverUrl: this.normalizeCover(data.pic ?? ""),
+          platform: "bilibili" as const,
+        };
       }
 
       return {
@@ -207,7 +266,7 @@ export class BiliBiliProvider implements MusicProvider {
         name: data.title ?? "",
         artist: data.owner?.name ?? "",
         album: "",
-        duration: data.duration ?? 0,
+        duration: targetPage?.duration ?? data.duration ?? 0,
         coverUrl: this.normalizeCover(data.pic ?? ""),
         platform: "bilibili" as const,
       };
@@ -216,9 +275,47 @@ export class BiliBiliProvider implements MusicProvider {
     }
   }
 
+  /** 获取视频所有分P列表 */
+  async getVideoParts(bvid: string): Promise<BiliVideoPartsResult | null> {
+    const { bvid: cleanBvid } = parseBilibiliId(bvid);
+    try {
+      const res = await this.api.get("/x/web-interface/view", {
+        params: { bvid: cleanBvid },
+        headers: this.cookieHeaders,
+      });
+
+      const data = res.data?.data;
+      if (!data) return null;
+
+      const pages = data.pages ?? [];
+      for (const p of pages) {
+        this.cidCache.set(`${cleanBvid}?p=${p.page}`, p.cid);
+      }
+      if (pages[0]?.cid) {
+        this.cidCache.set(cleanBvid, pages[0].cid);
+      }
+
+      return {
+        bvid: cleanBvid,
+        title: data.title ?? "",
+        coverUrl: this.normalizeCover(data.pic ?? ""),
+        artist: data.owner?.name ?? "",
+        parts: pages.map((p: any) => ({
+          part: p.page,
+          cid: p.cid,
+          title: p.part ?? `P${p.page}`,
+          duration: p.duration ?? 0,
+        })),
+      };
+    } catch {
+      return null;
+    }
+  }
+
   /** Get CID for a bvid, using cache when available */
-  private async getCid(bvid: string): Promise<number | null> {
-    const cached = this.cidCache.get(bvid);
+  private async getCid(bvid: string, page = 1): Promise<number | null> {
+    const key = page > 1 ? `${bvid}?p=${page}` : bvid;
+    const cached = this.cidCache.get(key) ?? (page === 1 ? this.cidCache.get(`${bvid}?p=1`) : undefined);
     if (cached) return cached;
 
     // Limit cache size to prevent unbounded growth
@@ -227,20 +324,22 @@ export class BiliBiliProvider implements MusicProvider {
       if (firstKey) this.cidCache.delete(firstKey);
     }
 
-    const detail = await this.getSongDetail(bvid);
+    const songId = page > 1 ? `${bvid}?p=${page}` : bvid;
+    const detail = await this.getSongDetail(songId);
     if (!detail) return null;
-    return this.cidCache.get(bvid) ?? null;
+    return this.cidCache.get(key) ?? this.cidCache.get(`${bvid}?p=${page}`) ?? this.cidCache.get(bvid) ?? null;
   }
 
   async getSongUrl(songId: string, _quality?: string): Promise<SongUrlResult | null> {
-    const cid = await this.getCid(songId);
+    const { bvid, page } = parseBilibiliId(songId);
+    const cid = await this.getCid(bvid, page);
     if (!cid) return null;
 
     try {
       const res = await this.api.get("/x/player/playurl", {
         params: {
           cid,
-          bvid: songId,
+          bvid,
           fnval: 16, // DASH format
         },
         headers: this.cookieHeaders,

src/music/jellyfin.test.ts

@@ -0,0 +1,386 @@
+import { describe, it, expect, vi } from "vitest";
+import {
+  ticksToSeconds,
+  TICKS_PER_SECOND,
+  buildCoverUrl,
+  buildStreamUrl,
+  buildUniversalUrl,
+  mapJellyfinSong,
+  mapJellyfinAlbum,
+  mapJellyfinPlaylist,
+  mapJellyfinLyrics,
+  describeJellyfinError,
+  JELLYFIN_QUALITY_LEVELS,
+  JellyfinProvider,
+} from "./jellyfin.js";
+import type { JellyfinConfig } from "../data/config.js";
+
+function cfg(partial: Partial<JellyfinConfig> = {}): JellyfinConfig {
+  return {
+    serverUrl: "https://jf.example.com",
+    authMode: "apikey",
+    username: "",
+    password: "",
+    apiKey: "KEY",
+    userId: "user-1",
+    ...partial,
+  };
+}
+
+/** Provider with a mocked axios instance; returns the request spy. */
+function mockProvider(config = cfg(), responder?: (req: any) => any) {
+  const p = new JellyfinProvider();
+  p.configure(config);
+  const request = vi.fn(async (req: any) => ({
+    data: responder ? responder(req) : { Items: [] },
+  }));
+  (p as any).api = { request, post: vi.fn() };
+  return { p, request };
+}
+
+describe("Jellyfin mapping helpers", () => {
+  it("converts ticks to seconds (1 tick = 100ns)", () => {
+    expect(ticksToSeconds(TICKS_PER_SECOND)).toBe(1);
+    expect(ticksToSeconds(2_275_000_000)).toBeCloseTo(227.5, 3);
+    expect(ticksToSeconds(undefined)).toBe(0);
+    expect(ticksToSeconds(NaN)).toBe(0);
+  });
+
+  it("maps a Jellyfin audio item to Song (GUID id stays a string)", () => {
+    const song = mapJellyfinSong(
+      {
+        Id: "3fa85f6457174562b3fc2c963f66afa6",
+        Name: "Track",
+        Artists: ["A", "B"],
+        AlbumArtist: "A",
+        Album: "The Album",
+        RunTimeTicks: 1_855_000_000,
+      },
+      "https://jf/x.jpg",
+    );
+    expect(song).toEqual({
+      id: "3fa85f6457174562b3fc2c963f66afa6",
+      name: "Track",
+      artist: "A / B",
+      album: "The Album",
+      duration: 186, // 185.5s rounded
+      coverUrl: "https://jf/x.jpg",
+      platform: "jellyfin",
+    });
+  });
+
+  it("falls back to AlbumArtist when Artists is empty", () => {
+    const song = mapJellyfinSong({ Id: "1", Artists: [], AlbumArtist: "Solo" }, "");
+    expect(song.artist).toBe("Solo");
+  });
+
+  it("maps albums and playlists with ChildCount", () => {
+    const album = mapJellyfinAlbum(
+      { Id: "a1", Name: "LP", AlbumArtist: "X", ChildCount: 10 },
+      "c",
+    );
+    expect(album).toMatchObject({ id: "a1", artist: "X", songCount: 10, platform: "jellyfin" });
+    const pl = mapJellyfinPlaylist({ Id: "p1", Name: "Mix", ChildCount: 7 }, "c");
+    expect(pl).toMatchObject({ id: "p1", songCount: 7, platform: "jellyfin" });
+  });
+
+  it("cover URL prefers the item's Primary image, falls back to the album's", () => {
+    const own = buildCoverUrl("https://jf", "K", {
+      Id: "i1",
+      ImageTags: { Primary: "tag1" },
+      AlbumId: "a1",
+      AlbumPrimaryImageTag: "tag2",
+    });
+    expect(own).toBe("https://jf/Items/i1/Images/Primary?maxWidth=512&tag=tag1&api_key=K");
+    const album = buildCoverUrl("https://jf", "K", {
+      Id: "i1",
+      AlbumId: "a1",
+      AlbumPrimaryImageTag: "tag2",
+    });
+    expect(album).toBe("https://jf/Items/a1/Images/Primary?maxWidth=512&tag=tag2&api_key=K");
+    expect(buildCoverUrl("https://jf", "K", { Id: "i1" })).toBe("");
+  });
+
+  it("builds direct and transcoded stream URLs", () => {
+    expect(buildStreamUrl("https://jf", "K", "i1")).toBe(
+      "https://jf/Audio/i1/stream?static=true&api_key=K",
+    );
+    const url = buildUniversalUrl("https://jf", {
+      apiKey: "K",
+      userId: "u",
+      deviceId: "d",
+      itemId: "i1",
+      kbps: 320,
+    });
+    expect(url).toContain("https://jf/Audio/i1/universal?");
+    expect(url).toContain("maxStreamingBitrate=320000");
+    expect(url).toContain("transcodingContainer=mp3");
+    expect(url).toContain("transcodingProtocol=http");
+    // The container list must be URL-encoded ("|" → %7C)
+    expect(url).toContain("container=mp3%2Caac%2Cm4a%7Caac%2Cflac%2Cwebma%2Cwebm%2Cwav%2Cogg");
+  });
+
+  it("maps lyrics with tick offsets; entries without Start collapse to 0; empty text dropped", () => {
+    const lines = mapJellyfinLyrics({
+      Lyrics: [
+        { Text: "line two", Start: 125_000_000 },
+        { Text: "line one", Start: 5_000_000 },
+        { Text: "   ", Start: 1 },
+        { Text: "untimed" },
+      ],
+    });
+    expect(lines).toEqual([
+      { time: 0, text: "untimed" },
+      { time: 0.5, text: "line one" },
+      { time: 12.5, text: "line two" },
+    ]);
+  });
+
+  it("mapJellyfinLyrics tolerates junk payloads", () => {
+    expect(mapJellyfinLyrics(null)).toEqual([]);
+    expect(mapJellyfinLyrics({})).toEqual([]);
+    expect(mapJellyfinLyrics({ Lyrics: "nope" })).toEqual([]);
+  });
+
+  it("describes common connection errors in a friendly way", () => {
+    expect(describeJellyfinError({ response: { status: 401 } })).toContain("401");
+    expect(describeJellyfinError({ code: "ECONNREFUSED" })).toContain("无法连接");
+    expect(describeJellyfinError(new Error("boom"))).toBe("boom");
+  });
+});
+
+describe("JellyfinProvider", () => {
+  it("quality: defaults to direct, ignores foreign (NetEase) values", () => {
+    const p = new JellyfinProvider();
+    expect(p.getQuality()).toBe("direct");
+    p.setQuality("exhigh"); // NetEase value from the legacy platform-less broadcast
+    expect(p.getQuality()).toBe("direct");
+    p.setQuality("320");
+    expect(p.getQuality()).toBe("320");
+    expect(JELLYFIN_QUALITY_LEVELS[0].value).toBe("direct");
+  });
+
+  it("getSongUrl: direct tier → static stream; 320 tier → universal transcode", async () => {
+    const { p } = mockProvider();
+    p.setCookie(JSON.stringify({ deviceId: "dev-1" }));
+    const direct = await p.getSongUrl("item1");
+    expect(direct?.url).toBe("https://jf.example.com/Audio/item1/stream?static=true&api_key=KEY");
+
+    p.setQuality("320");
+    const transcoded = await p.getSongUrl("item1");
+    expect(transcoded?.url).toContain("/Audio/item1/universal?");
+    expect(transcoded?.url).toContain("maxStreamingBitrate=320000");
+    expect(transcoded?.url).toContain("api_key=KEY");
+  });
+
+  it("search hits /Items for Audio, MusicAlbum and Playlist with paging", async () => {
+    const { p, request } = mockProvider();
+    await p.search("mozart", 30, 60);
+    const types = request.mock.calls.map((c) => c[0].params?.IncludeItemTypes);
+    expect(types).toContain("Audio");
+    expect(types).toContain("MusicAlbum");
+    expect(types).toContain("Playlist");
+    for (const call of request.mock.calls) {
+      expect(call[0].params.Limit).toBe(30);
+      expect(call[0].params.StartIndex).toBe(60);
+      expect(call[0].params.userId).toBe("user-1");
+      expect(call[0].headers["X-Emby-Token"]).toBe("KEY");
+    }
+  });
+
+  it("userpass: authenticates once via AuthenticateByName, persists token, retries once on 401", async () => {
+    const p = new JellyfinProvider();
+    p.configure(cfg({ authMode: "userpass", username: "eric", password: "pw", apiKey: "", userId: "" }));
+    const persisted: string[] = [];
+    p.setPersist((s) => persisted.push(s));
+
+    let tokenCounter = 0;
+    const post = vi.fn(async (..._args: any[]) => ({
+      data: { AccessToken: `tok-${++tokenCounter}`, User: { Id: "u9" } },
+    }));
+    // First data request 401s (expired token), the retry succeeds.
+    let dataCalls = 0;
+    const request = vi.fn(async (req: any) => {
+      dataCalls++;
+      if (dataCalls === 1) {
+        const err: any = new Error("Unauthorized");
+        err.response = { status: 401 };
+        throw err;
+      }
+      return { data: { Items: [{ Id: "s1", Name: "N" }] }, config: req };
+    });
+    (p as any).api = { request, post };
+
+    const songs = await p.getPlaylistSongs("pl1");
+    expect(songs).toHaveLength(1);
+    // login ran twice: initial auth + re-auth after the 401
+    expect(post).toHaveBeenCalledTimes(2);
+    const authHeader = post.mock.calls[0][2].headers.Authorization as string;
+    expect(authHeader).toContain('MediaBrowser Client="TSMusicBot"');
+    expect(authHeader).toContain("DeviceId=");
+    expect(post.mock.calls[0][1]).toEqual({ Username: "eric", Pw: "pw" });
+    // token + userId + deviceId persisted like cookies
+    const last = JSON.parse(persisted[persisted.length - 1]);
+    expect(last.accessToken).toBe("tok-2");
+    expect(last.userId).toBe("u9");
+    expect(last.deviceId).toBeTruthy();
+  });
+
+  it("userpass: surfaces the error when the retry also 401s (single retry only)", async () => {
+    const p = new JellyfinProvider();
+    p.configure(cfg({ authMode: "userpass", username: "eric", password: "bad", apiKey: "" }));
+    const post = vi.fn(async () => ({ data: { AccessToken: "t", User: { Id: "u" } } }));
+    const err: any = new Error("Unauthorized");
+    err.response = { status: 401 };
+    const request = vi.fn(async () => {
+      throw err;
+    });
+    (p as any).api = { request, post };
+    await expect(p.getPlaylistSongs("pl1")).rejects.toThrow("Unauthorized");
+    expect(request).toHaveBeenCalledTimes(2); // original + exactly one retry
+  });
+
+  it("setCookie/getCookie round-trip restores token, userId and deviceId", () => {
+    const p = new JellyfinProvider();
+    p.setCookie(JSON.stringify({ accessToken: "T", userId: "U", deviceId: "D" }));
+    expect(JSON.parse(p.getCookie())).toEqual({ accessToken: "T", userId: "U", deviceId: "D" });
+    p.setCookie("not json"); // junk must not corrupt state
+    expect(JSON.parse(p.getCookie())).toEqual({ accessToken: "T", userId: "U", deviceId: "D" });
+  });
+
+  it("getLyrics: 404 means no lyrics (empty), other errors surface", async () => {
+    const notFound: any = new Error("nf");
+    notFound.response = { status: 404 };
+    const { p } = mockProvider(cfg(), () => {
+      throw notFound;
+    });
+    expect(await p.getLyrics("i1")).toEqual([]);
+
+    const boom: any = new Error("server down");
+    boom.response = { status: 500 };
+    const { p: p2 } = mockProvider(cfg(), () => {
+      throw boom;
+    });
+    await expect(p2.getLyrics("i1")).rejects.toThrow("server down");
+  });
+
+  it("getAuthStatus reflects /System/Info reachability; unconfigured = logged out", async () => {
+    const blank = new JellyfinProvider();
+    expect(await blank.getAuthStatus()).toEqual({ loggedIn: false });
+
+    const { p } = mockProvider(cfg(), () => ({ ServerName: "NAS" }));
+    expect(await p.getAuthStatus()).toEqual({ loggedIn: true, nickname: "API Key@NAS" });
+
+    const { p: down } = mockProvider(cfg(), () => {
+      throw new Error("ECONNREFUSED");
+    });
+    expect(await down.getAuthStatus()).toEqual({ loggedIn: false });
+  });
+
+  it("getPersonalFm seeds InstantMix from a random favorite", async () => {
+    const { p, request } = mockProvider(cfg(), (req: any) => {
+      if (req.url.includes("/InstantMix")) {
+        return { Items: [{ Id: "m1", Name: "Mixed" }] };
+      }
+      if (req.params?.Filters === "IsFavorite") {
+        return { Items: [{ Id: "fav1", Name: "Fav" }] };
+      }
+      return { Items: [] };
+    });
+    const songs = await p.getPersonalFm();
+    expect(songs.map((s) => s.id)).toEqual(["m1"]);
+    const mixCall = request.mock.calls.find((c) => c[0].url.includes("/InstantMix"));
+    expect(mixCall![0].url).toContain("/Items/fav1/InstantMix");
+  });
+
+  it("getPersonalFm falls back: favorites → recently played → random", async () => {
+    const { p, request } = mockProvider(cfg(), (req: any) => {
+      if (req.url.includes("/InstantMix")) return { Items: [{ Id: "m2" }] };
+      if (req.params?.Filters === "IsFavorite") return { Items: [] };
+      if (req.params?.Filters === "IsPlayed") return { Items: [{ Id: "recent1" }] };
+      return { Items: [] };
+    });
+    const songs = await p.getPersonalFm();
+    expect(songs.map((s) => s.id)).toEqual(["m2"]);
+    const mixCall = request.mock.calls.find((c) => c[0].url.includes("/InstantMix"));
+    expect(mixCall![0].url).toContain("/Items/recent1/InstantMix");
+  });
+
+  it("playback reporter posts start/progress/stopped with PositionTicks", async () => {
+    const bodies: { url: string; data: any }[] = [];
+    const { p } = mockProvider(cfg(), () => ({}));
+    ((p as any).api.request as ReturnType<typeof vi.fn>).mockImplementation(
+      async (req: any) => {
+        bodies.push({ url: req.url, data: req.data });
+        return { data: {} };
+      },
+    );
+
+    const reporter = p.createPlaybackReporter();
+    reporter.onTrackStart("song1");
+    reporter.onTick("song1", 90.5, false);
+    reporter.onStop();
+    await vi.waitFor(() => expect(bodies).toHaveLength(3));
+
+    expect(bodies[0].url).toContain("/Sessions/Playing");
+    expect(bodies[0].data.ItemId).toBe("song1");
+    const sessionId = bodies[0].data.PlaySessionId;
+    expect(sessionId).toBeTruthy();
+
+    expect(bodies[1].url).toContain("/Sessions/Playing/Progress");
+    expect(bodies[1].data.PositionTicks).toBe(905_000_000);
+    expect(bodies[1].data.PlaySessionId).toBe(sessionId);
+
+    // Stop carries the LAST reported position so a natural track end counts as played.
+    expect(bodies[2].url).toContain("/Sessions/Playing/Stopped");
+    expect(bodies[2].data.PositionTicks).toBe(905_000_000);
+  });
+
+  it("reporter: a new track start closes the previous session; failures are swallowed", async () => {
+    const bodies: { url: string; data: any }[] = [];
+    const { p } = mockProvider(cfg(), () => ({}));
+    ((p as any).api.request as ReturnType<typeof vi.fn>).mockImplementation(
+      async (req: any) => {
+        bodies.push({ url: req.url, data: req.data });
+        if (req.url.includes("/Sessions")) throw new Error("reporting endpoint down");
+        return { data: {} };
+      },
+    );
+
+    const reporter = p.createPlaybackReporter();
+    reporter.onTrackStart("a");
+    reporter.onTick("a", 200, false);
+    reporter.onTrackStart("b"); // must post Stopped for "a" at pos 200, then Playing for "b"
+    reporter.onStop();
+    await vi.waitFor(() => expect(bodies.length).toBeGreaterThanOrEqual(5));
+
+    const stopped = bodies.filter((b) => b.url.includes("/Stopped"));
+    expect(stopped[0].data.ItemId).toBe("a");
+    expect(stopped[0].data.PositionTicks).toBe(2_000_000_000);
+    expect(stopped[1].data.ItemId).toBe("b");
+    // ticks for stale items are ignored
+    reporter.onTick("a", 999, false);
+    expect(bodies.filter((b) => b.url.includes("/Progress"))).toHaveLength(1);
+  });
+
+  it("testConnection reports server info on success and friendly errors on failure", async () => {
+    const { p } = mockProvider(cfg(), () => ({ ServerName: "NAS", Version: "10.9.11" }));
+    expect(await p.testConnection()).toEqual({ ok: true, serverName: "NAS", version: "10.9.11" });
+
+    const bad = new JellyfinProvider();
+    bad.configure(cfg({ apiKey: "", userId: "" }));
+    const res = await bad.testConnection();
+    expect(res.ok).toBe(false);
+    expect(res.error).toContain("apiKey");
+  });
+
+  it("configure drops the cached token when credentials change, keeps deviceId", () => {
+    const p = new JellyfinProvider();
+    p.configure(cfg());
+    p.setCookie(JSON.stringify({ accessToken: "T", userId: "U", deviceId: "D" }));
+    p.configure(cfg({ serverUrl: "https://other.example.com" }));
+    const state = JSON.parse(p.getCookie());
+    expect(state.accessToken).toBe("");
+    expect(state.deviceId).toBe("D");
+  });
+});

src/music/jellyfin.ts

@@ -0,0 +1,741 @@
+import { readFileSync } from "node:fs";
+import { dirname, join } from "node:path";
+import { fileURLToPath } from "node:url";
+import crypto from "node:crypto";
+import axios, { type AxiosError, type AxiosInstance } from "axios";
+import type { JellyfinConfig } from "../data/config.js";
+import type { Logger } from "../logger.js";
+import type {
+  MusicProvider,
+  Song,
+  SongUrlResult,
+  Playlist,
+  PlaylistDetail,
+  LyricLine,
+  SearchResult,
+  QrCodeResult,
+  AuthStatus,
+  Album,
+} from "./provider.js";
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+
+/** 1 tick = 100 ns → 10,000,000 ticks = 1 second (Jellyfin RunTimeTicks / lyric Start). */
+export const TICKS_PER_SECOND = 10_000_000;
+
+export function ticksToSeconds(ticks: number | null | undefined): number {
+  if (typeof ticks !== "number" || !Number.isFinite(ticks)) return 0;
+  return ticks / TICKS_PER_SECOND;
+}
+
+const CLIENT_NAME = "TSMusicBot";
+
+/** Best-effort package version for the MediaBrowser auth header. */
+const PKG_VERSION = (() => {
+  try {
+    const pkg = JSON.parse(
+      readFileSync(join(__dirname, "..", "..", "package.json"), "utf-8"),
+    ) as { version?: string };
+    return pkg.version ?? "0.0.0";
+  } catch {
+    return "0.0.0";
+  }
+})();
+
+// Jellyfin quality tiers replace the NetEase labels for this source. "direct"
+// (default) streams the original file — the bot re-encodes to Opus anyway, so
+// this is max quality. The transcode tiers exist for remote/low-bandwidth
+// Jellyfin servers.
+export const JELLYFIN_QUALITY_LEVELS = [
+  { value: "direct", label: "原始直传 Direct", bitrate: 0 },
+  { value: "320", label: "320kbps 转码", bitrate: 320 },
+  { value: "192", label: "192kbps 转码", bitrate: 192 },
+  { value: "128", label: "128kbps 转码", bitrate: 128 },
+] as const;
+
+/** Subset of Jellyfin's BaseItemDto that this provider consumes. */
+export interface JellyfinItem {
+  Id: string;
+  Name?: string;
+  Artists?: string[];
+  AlbumArtist?: string;
+  Album?: string;
+  AlbumId?: string;
+  AlbumPrimaryImageTag?: string;
+  RunTimeTicks?: number;
+  ImageTags?: { Primary?: string };
+  ChildCount?: number;
+  SongCount?: number;
+  Overview?: string;
+}
+
+/**
+ * Primary cover art URL for an item; falls back to the parent album's primary
+ * image (AlbumPrimaryImageTag) and finally to "" (the UI renders a placeholder
+ * for missing art). The api_key query param authenticates browser <img> loads
+ * and the TS-avatar download alike.
+ */
+export function buildCoverUrl(baseUrl: string, apiKey: string, item: JellyfinItem): string {
+  if (!baseUrl) return "";
+  const key = apiKey ? `&api_key=${encodeURIComponent(apiKey)}` : "";
+  if (item.ImageTags?.Primary) {
+    return `${baseUrl}/Items/${item.Id}/Images/Primary?maxWidth=512&tag=${item.ImageTags.Primary}${key}`;
+  }
+  if (item.AlbumId && item.AlbumPrimaryImageTag) {
+    return `${baseUrl}/Items/${item.AlbumId}/Images/Primary?maxWidth=512&tag=${item.AlbumPrimaryImageTag}${key}`;
+  }
+  return "";
+}
+
+/** Direct (untranscoded) stream URL — the default playback path. */
+export function buildStreamUrl(baseUrl: string, apiKey: string, itemId: string): string {
+  const params = new URLSearchParams({ static: "true", api_key: apiKey });
+  return `${baseUrl}/Audio/${itemId}/stream?${params.toString()}`;
+}
+
+/** Server-side transcode URL for the 320/192/128 kbps tiers. */
+export function buildUniversalUrl(
+  baseUrl: string,
+  o: { apiKey: string; userId: string; deviceId: string; itemId: string; kbps: number },
+): string {
+  const params = new URLSearchParams({
+    userId: o.userId,
+    deviceId: o.deviceId,
+    api_key: o.apiKey,
+    maxStreamingBitrate: String(o.kbps * 1000),
+    container: "mp3,aac,m4a|aac,flac,webma,webm,wav,ogg",
+    transcodingContainer: "mp3",
+    transcodingProtocol: "http",
+  });
+  return `${baseUrl}/Audio/${o.itemId}/universal?${params.toString()}`;
+}
+
+export function mapJellyfinSong(item: JellyfinItem, coverUrl: string): Song {
+  return {
+    id: String(item.Id),
+    name: item.Name ?? "",
+    artist: (item.Artists?.length ? item.Artists : [item.AlbumArtist ?? ""])
+      .filter(Boolean)
+      .join(" / "),
+    album: item.Album ?? "",
+    duration: Math.round(ticksToSeconds(item.RunTimeTicks)),
+    coverUrl,
+    platform: "jellyfin",
+  };
+}
+
+export function mapJellyfinAlbum(item: JellyfinItem, coverUrl: string): Album {
+  return {
+    id: String(item.Id),
+    name: item.Name ?? "",
+    artist: item.AlbumArtist ?? (item.Artists ?? []).join(" / "),
+    coverUrl,
+    songCount: item.ChildCount ?? item.SongCount ?? 0,
+    platform: "jellyfin",
+  };
+}
+
+export function mapJellyfinPlaylist(item: JellyfinItem, coverUrl: string): Playlist {
+  return {
+    id: String(item.Id),
+    name: item.Name ?? "",
+    coverUrl,
+    songCount: item.ChildCount ?? item.SongCount ?? 0,
+    platform: "jellyfin",
+  };
+}
+
+/**
+ * Map `GET /Audio/{id}/Lyrics` → the bot's synced-lyric format. `Start` is in
+ * ticks; entries without Start (plain-text lyrics) collapse to time 0 so the
+ * lyric view still renders them, just without sync. Translation stays empty —
+ * Jellyfin has no translated-lyrics concept.
+ */
+export function mapJellyfinLyrics(payload: unknown): LyricLine[] {
+  const lyrics = (payload as { Lyrics?: { Text?: string; Start?: number }[] })?.Lyrics;
+  if (!Array.isArray(lyrics)) return [];
+  return lyrics
+    .filter((l) => typeof l?.Text === "string" && l.Text.trim() !== "")
+    .map((l) => ({ time: ticksToSeconds(l.Start), text: l.Text!.trim() }))
+    .sort((a, b) => a.time - b.time);
+}
+
+/** Operator-friendly connection/auth error description (test-connection UI + logs). */
+export function describeJellyfinError(err: unknown): string {
+  const e = err as AxiosError;
+  if (e?.response) {
+    const s = e.response.status;
+    if (s === 401) return "认证失败：用户名/密码或 API Key 不正确 (401 Unauthorized)";
+    if (s === 403) return "该账号没有访问权限 (403 Forbidden)";
+    if (s === 404) return "接口不存在——请确认地址指向 Jellyfin 根路径 (404 Not Found)";
+    return `Jellyfin 返回 HTTP ${s}`;
+  }
+  const code = (e as { code?: string })?.code;
+  if (code === "ECONNREFUSED") return "无法连接 Jellyfin 服务器 (connection refused)";
+  if (code === "ENOTFOUND" || code === "EAI_AGAIN") return "无法解析服务器地址 (DNS lookup failed)";
+  if (code === "ETIMEDOUT" || code === "ECONNABORTED") return "连接 Jellyfin 超时 (timeout)";
+  return (err as Error)?.message ?? String(err);
+}
+
+/**
+ * Per-bot playback reporting handle. One playback session (PlaySessionId) per
+ * track start; the previous session is closed with its last known position so
+ * Jellyfin's played/PlayCount bookkeeping sees natural track ends as ~complete
+ * plays and mid-track skips as partial ones. Every call is fire-and-forget —
+ * reporting must never affect playback.
+ */
+export interface JellyfinPlaybackReporter {
+  onTrackStart(itemId: string): void;
+  onTick(itemId: string, positionSec: number, paused: boolean): void;
+  onStop(): void;
+}
+
+interface PersistedAuth {
+  accessToken?: string;
+  userId?: string;
+  deviceId?: string;
+}
+
+function emptyConfig(): JellyfinConfig {
+  return { serverUrl: "", authMode: "userpass", username: "", password: "", apiKey: "", userId: "" };
+}
+
+export class JellyfinProvider implements MusicProvider {
+  readonly platform = "jellyfin" as const;
+  private api: AxiosInstance;
+  private cfg: JellyfinConfig = emptyConfig();
+  private token = "";
+  private userId = "";
+  private deviceId = "";
+  private quality: string = "direct";
+  private loginPromise: Promise<void> | null = null;
+  private persistFn: ((serialized: string) => void) | null = null;
+  private logger: Logger | null = null;
+
+  constructor(logger?: Logger) {
+    this.api = axios.create({ timeout: 10000 });
+    this.logger = logger ?? null;
+  }
+
+  /**
+   * Apply (or re-apply, on settings save) the admin-configured connection.
+   * Changing any credential-relevant field drops the cached token so the next
+   * request re-authenticates; the stable deviceId survives reconfiguration.
+   */
+  configure(cfg: JellyfinConfig): void {
+    const prev = this.cfg;
+    this.cfg = { ...cfg, serverUrl: (cfg.serverUrl ?? "").trim().replace(/\/+$/, "") };
+    const credsChanged =
+      prev.serverUrl !== this.cfg.serverUrl ||
+      prev.authMode !== this.cfg.authMode ||
+      prev.username !== this.cfg.username ||
+      prev.password !== this.cfg.password ||
+      prev.apiKey !== this.cfg.apiKey ||
+      prev.userId !== this.cfg.userId;
+    if (credsChanged) {
+      this.token = "";
+      this.userId = "";
+    }
+  }
+
+  isConfigured(): boolean {
+    return this.cfg.serverUrl.length > 0;
+  }
+
+  /** Wire the on-disk persistence used after a successful login (cookie store). */
+  setPersist(fn: (serialized: string) => void): void {
+    this.persistFn = fn;
+  }
+
+  setQuality(quality: string): void {
+    // Ignore foreign values: the legacy platform-less POST /api/music/quality
+    // broadcasts NetEase levels to every provider, which must not clobber the
+    // jellyfin default ("direct").
+    if (JELLYFIN_QUALITY_LEVELS.some((l) => l.value === quality)) {
+      this.quality = quality;
+    }
+  }
+
+  getQuality(): string {
+    return this.quality;
+  }
+
+  // --- Auth ---
+
+  private authHeader(): string {
+    return (
+      `MediaBrowser Client="${CLIENT_NAME}", Device="${CLIENT_NAME}", ` +
+      `DeviceId="${this.deviceId}", Version="${PKG_VERSION}"`
+    );
+  }
+
+  private ensureDeviceId(): void {
+    if (!this.deviceId) {
+      this.deviceId = crypto.randomUUID();
+      this.persistState();
+    }
+  }
+
+  private persistState(): void {
+    try {
+      this.persistFn?.(this.getCookie());
+    } catch (err) {
+      this.logger?.warn({ err }, "Failed to persist Jellyfin auth state");
+    }
+  }
+
+  private async login(): Promise<void> {
+    this.ensureDeviceId();
+    const res = await this.api.post(
+      `${this.cfg.serverUrl}/Users/AuthenticateByName`,
+      { Username: this.cfg.username, Pw: this.cfg.password },
+      { headers: { Authorization: this.authHeader() } },
+    );
+    const token = res.data?.AccessToken as string | undefined;
+    const userId = res.data?.User?.Id as string | undefined;
+    if (!token || !userId) {
+      throw new Error("Jellyfin 登录响应缺少 AccessToken/User.Id");
+    }
+    this.token = token;
+    this.userId = userId;
+    this.persistState();
+    this.logger?.info({ userId }, "Jellyfin authenticated");
+  }
+
+  private async ensureAuth(): Promise<void> {
+    if (!this.cfg.serverUrl) {
+      throw new Error("Jellyfin 未配置服务器地址 (server URL not configured)");
+    }
+    if (this.cfg.authMode === "apikey") {
+      if (!this.cfg.apiKey || !this.cfg.userId) {
+        throw new Error("Jellyfin API Key 模式需要 apiKey 和 userId");
+      }
+      this.token = this.cfg.apiKey;
+      this.userId = this.cfg.userId;
+      this.ensureDeviceId();
+      return;
+    }
+    if (this.token && this.userId) return;
+    if (!this.cfg.username) {
+      throw new Error("Jellyfin 未配置用户名/密码 (username not configured)");
+    }
+    if (!this.loginPromise) {
+      this.loginPromise = this.login().finally(() => {
+        this.loginPromise = null;
+      });
+    }
+    return this.loginPromise;
+  }
+
+  /** Authenticated request with a single re-auth retry on 401 (userpass mode). */
+  private async request<T = unknown>(
+    method: "get" | "post",
+    path: string,
+    opts: { params?: Record<string, unknown>; data?: unknown; retried?: boolean } = {},
+  ): Promise<T> {
+    await this.ensureAuth();
+    // Callers snapshot `userId: this.userId` while building params, which is
+    // still empty before the first login. ensureAuth() has populated it by
+    // now, so backfill the stale-empty snapshot instead of sending userId="".
+    const params = opts.params ? { ...opts.params } : undefined;
+    if (params && "userId" in params && !params.userId) params.userId = this.userId;
+    try {
+      const res = await this.api.request<T>({
+        method,
+        url: this.cfg.serverUrl + path,
+        params,
+        data: opts.data,
+        headers: { "X-Emby-Token": this.token },
+      });
+      return res.data;
+    } catch (err) {
+      const status = (err as AxiosError).response?.status;
+      if (status === 401 && this.cfg.authMode === "userpass" && !opts.retried) {
+        this.token = "";
+        this.userId = "";
+        return this.request(method, path, { ...opts, retried: true });
+      }
+      throw err;
+    }
+  }
+
+  // --- MusicProvider ---
+
+  private coverFor(item: JellyfinItem): string {
+    return buildCoverUrl(this.cfg.serverUrl, this.token, item);
+  }
+
+  private mapSongs(items: JellyfinItem[] | undefined | null): Song[] {
+    return (items ?? []).map((i) => mapJellyfinSong(i, this.coverFor(i)));
+  }
+
+  async search(query: string, limit = 20, offset = 0): Promise<SearchResult> {
+    const common = {
+      searchTerm: query,
+      Recursive: true,
+      Limit: limit,
+      StartIndex: offset,
+      userId: this.userId,
+    };
+    const [songRes, albumRes, playlistRes] = await Promise.all([
+      this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+        params: { ...common, IncludeItemTypes: "Audio" },
+      }),
+      this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+        params: { ...common, IncludeItemTypes: "MusicAlbum", Fields: "ChildCount" },
+      }),
+      this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+        params: { ...common, IncludeItemTypes: "Playlist", Fields: "ChildCount" },
+      }),
+    ]);
+    return {
+      songs: this.mapSongs(songRes?.Items),
+      albums: (albumRes?.Items ?? []).map((i) => mapJellyfinAlbum(i, this.coverFor(i))),
+      playlists: (playlistRes?.Items ?? []).map((i) => mapJellyfinPlaylist(i, this.coverFor(i))),
+    };
+  }
+
+  async getSongUrl(songId: string, quality?: string): Promise<SongUrlResult | null> {
+    await this.ensureAuth();
+    const level = quality ?? this.quality;
+    const tier = JELLYFIN_QUALITY_LEVELS.find((l) => l.value === level);
+    if (!tier || tier.value === "direct") {
+      return { url: buildStreamUrl(this.cfg.serverUrl, this.token, songId) };
+    }
+    return {
+      url: buildUniversalUrl(this.cfg.serverUrl, {
+        apiKey: this.token,
+        userId: this.userId,
+        deviceId: this.deviceId,
+        itemId: songId,
+        kbps: tier.bitrate,
+      }),
+    };
+  }
+
+  async getSongDetail(songId: string): Promise<Song | null> {
+    const res = await this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+      params: { ids: songId, userId: this.userId },
+    });
+    const item = res?.Items?.[0];
+    return item ? mapJellyfinSong(item, this.coverFor(item)) : null;
+  }
+
+  async getPlaylistSongs(playlistId: string): Promise<Song[]> {
+    const res = await this.request<{ Items?: JellyfinItem[] }>(
+      "get",
+      `/Playlists/${playlistId}/Items`,
+      { params: { userId: this.userId } },
+    );
+    return this.mapSongs(res?.Items);
+  }
+
+  async getAlbumSongs(albumId: string): Promise<Song[]> {
+    const res = await this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+      params: {
+        parentId: albumId,
+        sortBy: "ParentIndexNumber,IndexNumber",
+        userId: this.userId,
+      },
+    });
+    return this.mapSongs(res?.Items);
+  }
+
+  async getRecommendPlaylists(): Promise<Playlist[]> {
+    return this.getUserPlaylists();
+  }
+
+  async getUserPlaylists(): Promise<Playlist[]> {
+    const res = await this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+      params: {
+        IncludeItemTypes: "Playlist",
+        Recursive: true,
+        Fields: "ChildCount",
+        SortBy: "SortName",
+        userId: this.userId,
+      },
+    });
+    return (res?.Items ?? []).map((i) => mapJellyfinPlaylist(i, this.coverFor(i)));
+  }
+
+  async getPlaylistDetail(playlistId: string): Promise<PlaylistDetail | null> {
+    const res = await this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+      params: { ids: playlistId, Fields: "ChildCount,Overview", userId: this.userId },
+    });
+    const item = res?.Items?.[0];
+    if (!item) return null;
+    return {
+      id: String(item.Id),
+      name: item.Name ?? "",
+      description: item.Overview ?? "",
+      coverUrl: this.coverFor(item),
+      songCount: item.ChildCount ?? 0,
+    };
+  }
+
+  async getLyrics(songId: string): Promise<LyricLine[]> {
+    try {
+      const res = await this.request<unknown>("get", `/Audio/${songId}/Lyrics`);
+      return mapJellyfinLyrics(res);
+    } catch (err) {
+      // 404 = the track simply has no lyrics — not an error.
+      if ((err as AxiosError).response?.status === 404) return [];
+      throw err;
+    }
+  }
+
+  // No QR-code login concept — connection is global and admin-configured.
+  async getQrCode(): Promise<QrCodeResult> {
+    return { qrUrl: "", key: "" };
+  }
+
+  async checkQrCodeStatus(): Promise<"waiting" | "scanned" | "confirmed" | "expired"> {
+    return "expired";
+  }
+
+  setCookie(cookie: string): void {
+    try {
+      const parsed = JSON.parse(cookie) as PersistedAuth;
+      if (parsed && typeof parsed === "object") {
+        if (typeof parsed.accessToken === "string") this.token = parsed.accessToken;
+        if (typeof parsed.userId === "string") this.userId = parsed.userId;
+        if (typeof parsed.deviceId === "string") this.deviceId = parsed.deviceId;
+      }
+    } catch {
+      // Not the JSON blob we persist — ignore rather than corrupt auth state.
+    }
+  }
+
+  getCookie(): string {
+    return JSON.stringify({
+      accessToken: this.token,
+      userId: this.userId,
+      deviceId: this.deviceId,
+    });
+  }
+
+  async getAuthStatus(): Promise<AuthStatus> {
+    if (!this.cfg.serverUrl) return { loggedIn: false };
+    try {
+      const info = await this.request<{ ServerName?: string }>("get", "/System/Info");
+      const who = this.cfg.authMode === "apikey" ? "API Key" : this.cfg.username;
+      return { loggedIn: true, nickname: `${who}@${info?.ServerName ?? "Jellyfin"}` };
+    } catch (err) {
+      this.logger?.debug({ err: describeJellyfinError(err) }, "Jellyfin auth status check failed");
+      return { loggedIn: false };
+    }
+  }
+
+  /**
+   * Authenticated round-trip to /System/Info for the Settings "test connection"
+   * button. `candidate` (when given) tests form values in a throwaway instance
+   * so a failed test never disturbs the live token state.
+   */
+  async testConnection(
+    candidate?: JellyfinConfig,
+  ): Promise<{ ok: boolean; serverName?: string; version?: string; error?: string }> {
+    const probe = candidate ? new JellyfinProvider() : this;
+    if (candidate) probe.configure(candidate);
+    try {
+      const info = await probe.request<{ ServerName?: string; Version?: string }>(
+        "get",
+        "/System/Info",
+      );
+      return { ok: true, serverName: info?.ServerName, version: info?.Version };
+    } catch (err) {
+      return { ok: false, error: describeJellyfinError(err) };
+    }
+  }
+
+  /**
+   * Personal FM = Instant Mix seeded from a random favorite, falling back to a
+   * random recently-played track, then a random library track. A final safety
+   * net returns 50 random tracks when Instant Mix itself yields nothing.
+   */
+  async getPersonalFm(): Promise<Song[]> {
+    const seed = await this.pickFmSeed();
+    if (seed) {
+      const mix = await this.request<{ Items?: JellyfinItem[] }>(
+        "get",
+        `/Items/${seed}/InstantMix`,
+        { params: { userId: this.userId, limit: 50 } },
+      );
+      const songs = this.mapSongs(mix?.Items);
+      if (songs.length > 0) return songs;
+    }
+    const random = await this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+      params: {
+        IncludeItemTypes: "Audio",
+        Recursive: true,
+        SortBy: "Random",
+        Limit: 50,
+        userId: this.userId,
+      },
+    });
+    return this.mapSongs(random?.Items);
+  }
+
+  private async pickFmSeed(): Promise<string | null> {
+    const favorite = await this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+      params: {
+        Filters: "IsFavorite",
+        IncludeItemTypes: "Audio",
+        Recursive: true,
+        SortBy: "Random",
+        Limit: 1,
+        userId: this.userId,
+      },
+    });
+    if (favorite?.Items?.[0]?.Id) return favorite.Items[0].Id;
+
+    const played = await this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+      params: {
+        Filters: "IsPlayed",
+        IncludeItemTypes: "Audio",
+        Recursive: true,
+        SortBy: "DatePlayed",
+        SortOrder: "Descending",
+        Limit: 20,
+        userId: this.userId,
+      },
+    });
+    const playedItems = played?.Items ?? [];
+    if (playedItems.length > 0) {
+      return playedItems[Math.floor(Math.random() * playedItems.length)].Id;
+    }
+
+    const random = await this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+      params: {
+        IncludeItemTypes: "Audio",
+        Recursive: true,
+        SortBy: "Random",
+        Limit: 1,
+        userId: this.userId,
+      },
+    });
+    return random?.Items?.[0]?.Id ?? null;
+  }
+
+  // --- Home sections ---
+
+  async getLatestAlbums(limit = 12): Promise<Album[]> {
+    await this.ensureAuth();
+    const items = await this.request<JellyfinItem[]>(
+      "get",
+      `/Users/${this.userId}/Items/Latest`,
+      { params: { IncludeItemTypes: "MusicAlbum", Limit: limit, Fields: "ChildCount" } },
+    );
+    return (Array.isArray(items) ? items : []).map((i) =>
+      mapJellyfinAlbum(i, this.coverFor(i)),
+    );
+  }
+
+  async getMostPlayed(limit = 12): Promise<Song[]> {
+    const res = await this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+      params: {
+        SortBy: "PlayCount",
+        SortOrder: "Descending",
+        IncludeItemTypes: "Audio",
+        Recursive: true,
+        Filters: "IsPlayed",
+        Limit: limit,
+        userId: this.userId,
+      },
+    });
+    return this.mapSongs(res?.Items);
+  }
+
+  async getFavoriteSongs(limit = 100): Promise<Song[]> {
+    const res = await this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+      params: {
+        Filters: "IsFavorite",
+        IncludeItemTypes: "Audio",
+        Recursive: true,
+        SortBy: "SortName",
+        Limit: limit,
+        userId: this.userId,
+      },
+    });
+    return this.mapSongs(res?.Items);
+  }
+
+  async getGenres(limit = 30): Promise<{ id: string; name: string }[]> {
+    const res = await this.request<{ Items?: JellyfinItem[] }>("get", "/MusicGenres", {
+      params: { userId: this.userId, Limit: limit, SortBy: "SortName" },
+    });
+    return (res?.Items ?? []).map((i) => ({ id: String(i.Id), name: i.Name ?? "" }));
+  }
+
+  async getGenreSongs(genreId: string, limit = 100): Promise<Song[]> {
+    const res = await this.request<{ Items?: JellyfinItem[] }>("get", "/Items", {
+      params: {
+        GenreIds: genreId,
+        IncludeItemTypes: "Audio",
+        Recursive: true,
+        SortBy: "AlbumArtist,Album,SortName",
+        Limit: limit,
+        userId: this.userId,
+      },
+    });
+    return this.mapSongs(res?.Items);
+  }
+
+  // --- Playback reporting (Sessions API) ---
+
+  private async report(path: string, body: Record<string, unknown>): Promise<void> {
+    try {
+      await this.request("post", path, { data: body });
+    } catch (err) {
+      // Reporting must never affect playback — log and swallow.
+      this.logger?.debug(
+        { err: describeJellyfinError(err), path },
+        "Jellyfin playback report failed",
+      );
+    }
+  }
+
+  createPlaybackReporter(): JellyfinPlaybackReporter {
+    // One session per track start; remember the last reported position so the
+    // implicit stop on track change carries a sane PositionTicks (a natural
+    // track end reports ~full duration → Jellyfin counts the play).
+    let current: { itemId: string; sessionId: string; lastPosSec: number } | null = null;
+    const report = this.report.bind(this);
+    return {
+      onTrackStart(itemId: string): void {
+        if (current) {
+          void report("/Sessions/Playing/Stopped", {
+            ItemId: current.itemId,
+            PlaySessionId: current.sessionId,
+            PositionTicks: Math.round(current.lastPosSec * TICKS_PER_SECOND),
+          });
+        }
+        current = { itemId, sessionId: crypto.randomUUID(), lastPosSec: 0 };
+        void report("/Sessions/Playing", {
+          ItemId: itemId,
+          PlaySessionId: current.sessionId,
+          PositionTicks: 0,
+          CanSeek: true,
+        });
+      },
+      onTick(itemId: string, positionSec: number, paused: boolean): void {
+        if (!current || current.itemId !== itemId) return;
+        current.lastPosSec = positionSec;
+        void report("/Sessions/Playing/Progress", {
+          ItemId: itemId,
+          PlaySessionId: current.sessionId,
+          PositionTicks: Math.round(positionSec * TICKS_PER_SECOND),
+          IsPaused: paused,
+        });
+      },
+      onStop(): void {
+        if (!current) return;
+        void report("/Sessions/Playing/Stopped", {
+          ItemId: current.itemId,
+          PlaySessionId: current.sessionId,
+          PositionTicks: Math.round(current.lastPosSec * TICKS_PER_SECOND),
+        });
+        current = null;
+      },
+    };
+  }
+}

src/music/kugou.test.ts

@@ -0,0 +1,224 @@
+import { describe, it, expect, vi } from "vitest";
+import { mapKugouSong, mapKugouSongs, mapKugouAlbums, mapKugouPlaylist, mapKugouPlaylists, krcToLrc, KugouProvider } from "./kugou.js";
+import { parseLyrics } from "./netease.js";
+
+describe("mapKugouSongs", () => {
+  it("maps the mobile-search song shape to a Song with platform 'kugou'", () => {
+    // Shape captured live from mobilecdn.kugou.com/api/v3/search/song.
+    const raw = {
+      hash: "B3A52A7A958BF0AED0EBFBA2E9A818B7",
+      album_audio_id: 32100650,
+      album_id: "966846",
+      songname: "晴天",
+      singername: "周杰伦",
+      duration: 269,
+    };
+    const [song] = mapKugouSongs([raw]);
+    expect(song.platform).toBe("kugou");
+    expect(song.name).toBe("晴天");
+    expect(song.artist).toBe("周杰伦");
+    expect(song.duration).toBe(269);
+    // The id must round-trip hash + album_audio_id + album_id so getSongUrl
+    // can resolve a stream from a search result.
+    expect(song.id).toBe("b3a52a7a958bf0aed0ebfba2e9a818b7|32100650|966846");
+  });
+
+  it("treats nested audio_info durations as milliseconds and flat search durations as seconds", () => {
+    // List endpoints: ms under audio_info.
+    expect(mapKugouSong({ audio_info: { hash: "abc", duration: 215000 } }).duration).toBe(215);
+    // Search endpoint: a long-form track's flat `duration` stays seconds (no /1000).
+    expect(mapKugouSong({ hash: "abc", songname: "x", duration: 10800 }).duration).toBe(10800);
+  });
+
+  it("falls back to splitting '歌手 - 歌名' from the filename", () => {
+    const song = mapKugouSong({ FileHash: "deadbeef", filename: "周杰伦 - 稻香", Duration: 200 });
+    expect(song.artist).toBe("周杰伦");
+    expect(song.name).toBe("稻香");
+  });
+
+  it("uses PascalCase fields from the gateway shape and skips entries with no hash", () => {
+    const songs = mapKugouSongs([
+      { FileHash: "aa", SongName: "n", SingerName: "s", MixSongID: 1, AlbumID: 2 },
+      { songname: "no hash" } as any,
+    ]);
+    expect(songs).toHaveLength(1);
+    expect(songs[0].id).toBe("aa|1|2");
+  });
+
+  it("returns [] for non-array input", () => {
+    expect(mapKugouSongs(undefined)).toEqual([]);
+  });
+
+  it("maps the NESTED album/playlist track shape (base + audio_info)", () => {
+    // Shape captured live from /album/songs (叶惠美).
+    const raw = {
+      base: { album_id: 966846, album_audio_id: 32100648, audio_name: "以父之名", author_name: "周杰伦" },
+      audio_info: { hash: "DBC0207490EB51153EF933EF5A7E98E4", duration: 342047 },
+    };
+    const [song] = mapKugouSongs([raw]);
+    expect(song.name).toBe("以父之名");
+    expect(song.artist).toBe("周杰伦");
+    expect(song.duration).toBe(342); // ms → s
+    expect(song.id).toBe("dbc0207490eb51153ef933ef5a7e98e4|32100648|966846");
+  });
+});
+
+describe("krcToLrc", () => {
+  it("converts KRC [startMs,durMs] line timestamps + strips word timings into parseable LRC", () => {
+    // Shape captured live from lyrics.kugou.com (周杰伦 - 晴天).
+    const krc = [
+      "[ti:晴天]",
+      "[ar:周杰伦]",
+      "[0,2250]<0,160,0>晴<160,160,0>天",
+      "[63000,1800]<0,200,0>故<200,200,0>事",
+    ].join("\n");
+    const lrc = krcToLrc(krc);
+    expect(lrc).toContain("[00:00.00]晴天");
+    expect(lrc).toContain("[01:03.00]故事");
+    expect(lrc).not.toMatch(/<\d+,\d+,\d+>/); // word timings stripped
+
+    // And the shared LRC parser must now actually produce timed lines.
+    const lines = parseLyrics(lrc);
+    expect(lines.length).toBe(2);
+    expect(lines[0]).toEqual({ time: 0, text: "晴天" });
+    expect(lines[1].time).toBe(63);
+    expect(lines[1].text).toBe("故事");
+  });
+});
+
+describe("mapKugouAlbums", () => {
+  it("maps album shape and normalises {size} covers to https", () => {
+    const [album] = mapKugouAlbums([
+      { album_id: 966846, album_name: "叶惠美", singername: "周杰伦", sizable_cover: "http://imge.kugou.com/x/{size}/abc.jpg", songcount: 11 },
+    ]);
+    expect(album.platform).toBe("kugou");
+    expect(album.id).toBe("966846");
+    expect(album.name).toBe("叶惠美");
+    expect(album.coverUrl).toBe("https://imge.kugou.com/x/240/abc.jpg");
+    expect(album.songCount).toBe(11);
+  });
+});
+
+describe("mapKugouSong — playlist (get_other_list_file) shape", () => {
+  it("splits the combined `name` and uses `mixsongid` as the audio id", () => {
+    // Shape captured live from /pubsongs/v2/get_other_list_file_nofilt (我喜欢).
+    // The combined "歌手 - 歌名" is in `name`; there is no separate songname.
+    const raw = {
+      name: "KOKIA - ありがとう… (谢谢…)",
+      hash: "E9A08A98614DD992F11A68A5E5F1C79F",
+      album_id: "1491689",
+      mixsongid: 37533796,
+      timelen: 248528, // ms
+      cover: "http://imge.kugou.com/stdmusic/{size}/20210113/x.jpg",
+    };
+    const song = mapKugouSong(raw);
+    expect(song.artist).toBe("KOKIA");
+    expect(song.name).toBe("ありがとう… (谢谢…)");
+    // hash lowercased | mixsongid | album_id — so getSongUrl can resolve it.
+    expect(song.id).toBe("e9a08a98614dd992f11a68a5e5f1c79f|37533796|1491689");
+    expect(song.duration).toBe(249); // timelen ms → s
+    expect(song.coverUrl).toBe("https://imge.kugou.com/stdmusic/240/20210113/x.jpg");
+  });
+});
+
+describe("mapKugouSong — cover art per endpoint", () => {
+  it("reads `sizable_cover` (daily/FM shape) and resolves {size}→240, http→https", () => {
+    const song = mapKugouSong({
+      hash: "abc",
+      songname: "x",
+      duration: 200,
+      sizable_cover: "http://imge.kugou.com/stdmusic/{size}/y.jpg",
+    });
+    expect(song.coverUrl).toBe("https://imge.kugou.com/stdmusic/240/y.jpg");
+  });
+
+  it("falls back to `trans_param.union_cover` (search shape, no top-level cover)", () => {
+    const song = mapKugouSong({
+      hash: "abc",
+      songname: "x",
+      duration: 200,
+      trans_param: { union_cover: "http://imge.kugou.com/stdmusic/{size}/z.jpg" },
+    });
+    expect(song.coverUrl).toBe("https://imge.kugou.com/stdmusic/240/z.jpg");
+  });
+
+  it("returns an empty coverUrl when no cover field is present", () => {
+    expect(mapKugouSong({ hash: "abc", songname: "x", duration: 200 }).coverUrl).toBe("");
+  });
+
+  it("skips an empty-string cover field (Kugou returns '') and uses the next non-empty source", () => {
+    const song = mapKugouSong({
+      hash: "abc",
+      songname: "x",
+      duration: 200,
+      sizable_cover: "", // present but empty — must NOT mask the real cover below
+      trans_param: { union_cover: "http://imge.kugou.com/stdmusic/{size}/z.jpg" },
+    });
+    expect(song.coverUrl).toBe("https://imge.kugou.com/stdmusic/240/z.jpg");
+  });
+});
+
+describe("mapKugouPlaylists", () => {
+  it("maps the user-playlist shape (/v7/get_all_list info), keying id on global_collection_id", () => {
+    // Shape captured live from /v7/get_all_list (我喜欢).
+    const [pl] = mapKugouPlaylists([
+      { name: "我喜欢", count: 7, global_collection_id: "collection_3_2526507197_2_0", listid: 2, type: 0 },
+    ]);
+    expect(pl.platform).toBe("kugou");
+    expect(pl.name).toBe("我喜欢");
+    expect(pl.songCount).toBe(7);
+    // Must be the global_collection_id — the only id getPlaylistSongs can open.
+    expect(pl.id).toBe("collection_3_2526507197_2_0");
+  });
+
+  it("maps the recommend shape (/v2/special_recommend), preferring global_collection_id over specialid", () => {
+    // Shape captured live from /v2/special_recommend special_list.
+    const pl = mapKugouPlaylist({
+      specialname: "米津玄师：蒙着眼睛也能炸翻全场",
+      specialid: 1154672,
+      global_collection_id: "collection_1_1029965246_1154672_0",
+      pic: "http://imge.kugou.com/specialimg/{size}/a.jpg",
+      percount: 0,
+    });
+    expect(pl.id).toBe("collection_1_1029965246_1154672_0");
+    expect(pl.name).toBe("米津玄师：蒙着眼睛也能炸翻全场");
+    expect(pl.coverUrl).toBe("https://imge.kugou.com/specialimg/240/a.jpg");
+  });
+
+  it("drops entries whose only id is a non-openable specialid/listid (not a global_collection_id)", () => {
+    // getPlaylistSongs can only open a global_collection_id, so a numeric
+    // specialid/listid would be a dead id — such entries must be dropped.
+    expect(mapKugouPlaylists([{ specialname: "x", specialid: 1154672, listid: 9 }])).toHaveLength(0);
+    expect(mapKugouPlaylists([{ name: "no id" }])).toHaveLength(0);
+    expect(mapKugouPlaylists(undefined)).toEqual([]);
+  });
+});
+
+describe("KugouProvider.search pagination", () => {
+  function mockProvider() {
+    const p = new KugouProvider();
+    const get = vi.fn().mockResolvedValue({ data: { data: { info: [] } } });
+    (p as any).mobileHttp = { get };
+    return { p, get };
+  }
+
+  function searchParams(get: ReturnType<typeof vi.fn>) {
+    const call = get.mock.calls[0];
+    expect(call, "expected a mobile search call").toBeTruthy();
+    return call[1].params as Record<string, unknown>;
+  }
+
+  it("sets page to offset/limit+1 and keeps pagesize=limit", async () => {
+    const { p, get } = mockProvider();
+    await p.search("hello", 20, 20); // page 2
+    const params = searchParams(get);
+    expect(params.page).toBe(2);
+    expect(params.pagesize).toBe(20);
+  });
+
+  it("defaults offset to 0 → page 1 (backward compatible)", async () => {
+    const { p, get } = mockProvider();
+    await p.search("hello", 20);
+    expect(searchParams(get).page).toBe(1);
+  });
+});

src/music/local-extract-fallback.test.ts

@@ -0,0 +1,109 @@
+import { describe, it, expect, beforeEach, afterEach, vi } from "vitest";
+// unlinkSync/rmdirSync are NOT mocked below, so the test's own fixture
+// teardown is unaffected by the simulated lock on *.mp4.
+import { mkdtempSync, statSync, existsSync, readFileSync, unlinkSync, readdirSync, rmdirSync } from "node:fs";
+import { spawnSync } from "node:child_process";
+import { createRequire } from "node:module";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+
+/**
+ * #149: when the audio track is extracted successfully but the source video
+ * cannot be deleted (Windows keeps files locked briefly — rmSync with
+ * force:true still throws EBUSY/EPERM), the record must fall back to the
+ * ORIGINAL container completely: both the path AND the recorded size.
+ *
+ * Committing the size before the delete succeeded would leave the record
+ * claiming the small extracted size while still holding the whole video, so
+ * totalBytes() under-counts and the upload directory grows past its quota.
+ *
+ * This lives in its own file because it partially mocks node:fs, which would
+ * otherwise leak into every other test in local.test.ts.
+ */
+vi.mock("node:fs", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("node:fs")>();
+  return {
+    ...actual,
+    default: actual,
+    rmSync: (path: string, opts?: object) => {
+      // Simulate the lock on the source video only; every other delete
+      // (the discarded .mka, temp dirs, the reject path) behaves normally.
+      if (typeof path === "string" && path.endsWith(".mp4")) {
+        const err = new Error("EBUSY: resource busy or locked") as NodeJS.ErrnoException;
+        err.code = "EBUSY";
+        throw err;
+      }
+      return actual.rmSync(path, opts as never);
+    },
+  };
+});
+
+const { LocalMusicProvider } = await import("./local.js");
+
+const ffmpeg: string | null = (() => {
+  try {
+    return createRequire(import.meta.url)("ffmpeg-static") as string;
+  } catch {
+    return null;
+  }
+})();
+const have = !!ffmpeg && spawnSync(ffmpeg, ["-version"], { stdio: "ignore" }).status === 0;
+
+let dir: string;
+beforeEach(() => { dir = mkdtempSync(join(tmpdir(), "local-extract-fallback-")); });
+afterEach(() => {
+  // Recursive teardown without rmSync (mocked above for *.mp4).
+  for (const f of readdirSync(dir)) {
+    try { unlinkSync(join(dir, f)); } catch { /* best effort */ }
+  }
+  try { rmdirSync(dir); } catch { /* best effort */ }
+});
+
+describe("LocalMusicProvider: source video cannot be deleted after extraction (#149)", () => {
+  it.runIf(have)("keeps the original container AND its real size, not the extracted size", async () => {
+    const src = join(dir, "fixture.mp4");
+    const r = spawnSync(ffmpeg!, [
+      "-y", "-hide_banner", "-loglevel", "error",
+      "-f", "lavfi", "-i", "testsrc=s=320x240:r=25:d=3",
+      "-f", "lavfi", "-i", "sine=f=440:d=3",
+      "-c:v", "libx264", "-b:v", "800k", "-c:a", "aac", "-shortest", src,
+    ], { stdio: "ignore" });
+    expect(r.status).toBe(0);
+
+    const bytes = readFileSync(src);
+    unlinkSync(src); // uploadAudio writes its own copy under a uuid name
+
+    const p = new LocalMusicProvider(dir);
+    const song = await p.uploadAudio({
+      buffer: bytes, originalName: "fixture.mp4", mimeType: "video/mp4",
+    });
+
+    const resolved = await p.getSongUrl(song.id);
+    expect(resolved).not.toBeNull();
+
+    // Fell back to the original container — the extract was discarded.
+    expect(resolved!.url.endsWith(".mp4")).toBe(true);
+    expect(existsSync(resolved!.url)).toBe(true);
+    expect(existsSync(resolved!.url.replace(/\.mp4$/, ".m4a"))).toBe(false);
+    expect(existsSync(resolved!.url.replace(/\.mp4$/, ".mka"))).toBe(false);
+
+    const onDisk = statSync(resolved!.url).size;
+    expect(onDisk).toBe(bytes.length);
+
+    // The RECORDED size drives the quota (totalBytes()), so it must describe
+    // the file actually retained. It is not exposed through search()/toSong,
+    // but it is persisted to index.json — read it back from there.
+    const record = (JSON.parse(readFileSync(join(dir, "index.json"), "utf8")) as Array<{
+      id: string; size: number; filePath: string;
+    }>).find((r) => r.id === song.id);
+    expect(record).toBeDefined();
+    expect(record!.filePath.endsWith(".mp4")).toBe(true);
+    // Before the fix this was the (much smaller) .mka size while the whole
+    // .mp4 stayed on disk, so the quota under-counted the retained bytes.
+    expect(record!.size).toBe(bytes.length);
+
+    // Sanity: the extract really is much smaller, so a wrong commit order
+    // would have been clearly observable rather than a rounding error.
+    expect(onDisk).toBeGreaterThan(50_000);
+  }, 60000);
+});

src/music/local.test.ts

@@ -1,8 +1,11 @@
 import { describe, it, expect, beforeEach, afterEach } from "vitest";
-import { mkdtempSync, rmSync, existsSync, writeFileSync } from "node:fs";
+import { mkdtempSync, rmSync, existsSync, writeFileSync, readFileSync, readdirSync, statSync } from "node:fs";
+import { spawnSync } from "node:child_process";
+import { createRequire } from "node:module";
+import { buildFfmpegArgs } from "../audio/player.js";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
-import { LocalMusicProvider } from "./local.js";
+import { LocalMusicProvider, parseMediaProbe } from "./local.js";
 
 let dir: string;
 
@@ -149,6 +152,115 @@ describe("LocalMusicProvider upload validation", () => {
       p.uploadAudio({ buffer: Buffer.alloc(0), originalName: "a.mp3" }),
     ).rejects.toThrow();
   });
+
+  // #149: video containers are accepted; only their audio track is kept.
+  it("still rejects a non-media extension after video was allowed", async () => {
+    const p = new LocalMusicProvider(dir);
+    for (const name of ["evil.exe", "evil.html", "evil.mp4.txt", "notes.pdf"]) {
+      await expect(
+        p.uploadAudio({ buffer: Buffer.from("x"), originalName: name, mimeType: "video/mp4" }),
+      ).rejects.toThrow();
+    }
+  });
+
+  it("accepts every supported video extension at the extension gate", async () => {
+    const p = new LocalMusicProvider(dir);
+    // Junk content: ffmpeg cannot open it, so it is "unrecognised" rather than
+    // "no audio track" and must be accepted exactly like a truncated .mp3
+    // always has been. The extension allowlist is what is under test here.
+    // .m4v is excluded on purpose — see the next test.
+    for (const ext of [".mp4", ".mov", ".avi", ".mkv", ".flv", ".wmv", ".mpg", ".mpeg", ".3gp", ".ts", ".m2ts", ".ogv"]) {
+      const song = await p.uploadAudio({
+        buffer: Buffer.from("not really a video"),
+        originalName: `clip${ext}`,
+        mimeType: "video/mp4",
+      });
+      expect(song.platform).toBe("local");
+      expect(song.name).toBe("clip");
+    }
+  });
+
+  it("refuses a .m4v raw video elementary stream, which by definition has no audio", async () => {
+    // .m4v is not a container — ffmpeg's rawvideo demuxer opens arbitrary
+    // bytes as an MPEG-4 video elementary stream, so it IS recognised and
+    // genuinely carries no audio track. Refusing it is the correct outcome,
+    // and it is the one case that distinguishes `recognized` from `probed`.
+    const p = new LocalMusicProvider(dir);
+    await expect(
+      p.uploadAudio({
+        buffer: Buffer.from("not really a video"),
+        originalName: "clip.m4v",
+        mimeType: "video/x-m4v",
+      }),
+    ).rejects.toThrow(/音轨/);
+  });
+
+  it("the error message names both audio and video formats", async () => {
+    const p = new LocalMusicProvider(dir);
+    await expect(
+      p.uploadAudio({ buffer: Buffer.from("x"), originalName: "a.exe" }),
+    ).rejects.toThrow(/视频/);
+  });
+});
+
+describe("parseMediaProbe (#149)", () => {
+  const mp4Banner = `Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'clip.mp4':
+  Duration: 00:03:27.15, start: 0.000000, bitrate: 1105 kb/s
+  Stream #0:0[0x1](und): Video: h264 (High), yuv420p, 1280x720, 30 fps
+  Stream #0:1[0x2](und): Audio: aac (LC), 48000 Hz, stereo, fltp, 192 kb/s`;
+
+  it("reads duration and detects the audio stream in a video container", () => {
+    const r = parseMediaProbe(mp4Banner);
+    expect(r.durationSeconds).toBe(3 * 60 + 27);
+    expect(r.hasAudio).toBe(true);
+  });
+
+  it("reports hasAudio false for a video with only a video stream", () => {
+    const silent = `Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'silent.mp4':
+  Duration: 00:00:02.00, start: 0.000000, bitrate: 29 kb/s
+  Stream #0:0[0x1](und): Video: h264 (High 4:4:4 Predictive), yuv444p, 160x120, 10 fps`;
+    const r = parseMediaProbe(silent);
+    expect(r.durationSeconds).toBe(2);
+    expect(r.hasAudio).toBe(false);
+  });
+
+  it("detects a plain audio file", () => {
+    const r = parseMediaProbe(`Input #0, mp3, from 'a.mp3':
+  Duration: 00:00:30.02, start: 0.000000, bitrate: 128 kb/s
+  Stream #0:0: Audio: mp3, 44100 Hz, stereo, fltp, 128 kb/s`);
+    expect(r.durationSeconds).toBe(30);
+    expect(r.hasAudio).toBe(true);
+  });
+
+  it("does not mistake an attached cover image for an audio stream", () => {
+    const r = parseMediaProbe(`Input #0, mp3, from 'cover.mp3':
+  Duration: 00:00:10.00, start: 0.000000, bitrate: 130 kb/s
+  Stream #0:0: Audio: mp3, 44100 Hz, stereo, fltp, 128 kb/s
+  Stream #0:1: Video: mjpeg (Baseline), yuvj420p(pc), 100x100 [attached pic]`);
+    expect(r.hasAudio).toBe(true);
+  });
+
+  it("returns zeros on unparseable output rather than throwing", () => {
+    const r = parseMediaProbe("ffmpeg: command exploded");
+    expect(r.durationSeconds).toBe(0);
+    expect(r.hasAudio).toBe(false);
+    expect(r.recognized).toBe(false);
+  });
+
+  // The distinction that decides whether an upload is refused: ffmpeg opened
+  // the file and found no audio (refuse) vs ffmpeg could not open it at all
+  // (accept, as it always has for truncated audio).
+  it("marks a readable container recognized and unreadable bytes not", () => {
+    expect(parseMediaProbe(mp4Banner).recognized).toBe(true);
+    expect(parseMediaProbe(`[mov,mp4,m4a,3gp,3g2,mj2 @ 0x1] moov atom not found
+[in#0 @ 0x2] Error opening input: Invalid data found when processing input
+Error opening input file junk.mp4.`).recognized).toBe(false);
+  });
+
+  it("rounds fractional durations", () => {
+    expect(parseMediaProbe("Duration: 00:00:03.60,").durationSeconds).toBe(4);
+    expect(parseMediaProbe("Duration: 01:02:03.10,").durationSeconds).toBe(3723);
+  });
 });
 
 describe("LocalMusicProvider quota", () => {
@@ -205,6 +317,20 @@ describe("LocalMusicProvider quota", () => {
   });
 });
 
+describe("LocalMusicProvider search pagination", () => {
+  it("slices [offset, offset+limit) instead of the first page", async () => {
+    const recs = ["a", "b", "c", "d"].map((id) => makeRecord(id));
+    seed(recs); // newest-first order preserved: a, b, c, d
+    const p = new LocalMusicProvider(dir);
+
+    const page1 = await p.search("", 2); // offset defaults to 0
+    expect(page1.songs.map((s) => s.id)).toEqual(["a", "b"]);
+
+    const page2 = await p.search("", 2, 2);
+    expect(page2.songs.map((s) => s.id)).toEqual(["c", "d"]);
+  });
+});
+
 describe("LocalMusicProvider filename handling", () => {
   it("accepts a long filename without dropping its extension", async () => {
     const p = new LocalMusicProvider(dir);
@@ -219,3 +345,146 @@ describe("LocalMusicProvider filename handling", () => {
     expect(await p.getSongUrl(song.id)).not.toBeNull();
   });
 });
+
+// #149 end-to-end: build real containers with the bundled ffmpeg and push
+// them through the actual upload path. Skipped automatically if the binary is
+// unavailable, so the suite still runs on a machine without it.
+describe("LocalMusicProvider video upload, end to end (#149)", () => {
+  const ffmpeg: string | null = (() => {
+    try {
+      return createRequire(import.meta.url)("ffmpeg-static") as string;
+    } catch {
+      return null;
+    }
+  })();
+
+  const have = !!ffmpeg && spawnSync(ffmpeg, ["-version"], { stdio: "ignore" }).status === 0;
+
+  /** Render a real container into the temp dir and return its bytes. */
+  function render(name: string, args: string[]): Buffer {
+    const out = join(dir, name);
+    const r = spawnSync(ffmpeg!, ["-y", "-hide_banner", "-loglevel", "error", ...args, out], {
+      stdio: "ignore",
+    });
+    if (r.status !== 0) throw new Error(`fixture render failed: ${name}`);
+    const buf = readFileSync(out);
+    rmSync(out, { force: true }); // upload writes its own copy
+    return buf;
+  }
+
+  const withAudio = (dur: number, vcodec: string, acodec: string) => [
+    "-f", "lavfi", "-i", `testsrc=s=160x120:r=10:d=${dur}`,
+    "-f", "lavfi", "-i", `sine=f=440:d=${dur}`,
+    "-c:v", vcodec, "-c:a", acodec, "-shortest",
+  ];
+
+  it.runIf(have)("accepts an mp4, reads its duration, and keeps only the audio", async () => {
+    const p = new LocalMusicProvider(dir);
+    const mp4 = render("src.mp4", withAudio(3, "libx264", "aac"));
+    const song = await p.uploadAudio({
+      buffer: mp4, originalName: "My Clip.mp4", mimeType: "video/mp4",
+    });
+
+    expect(song.name).toBe("My Clip");
+    expect(song.platform).toBe("local");
+    expect(song.duration).toBe(3);
+
+    const resolved = await p.getSongUrl(song.id);
+    expect(resolved).not.toBeNull();
+    // The video container is gone; what remains is the extracted audio track.
+    // AAC (what libx264+aac mp4s carry) goes to .m4a so the encoder-priming
+    // edit list survives — see extractedAudioExt.
+    expect(resolved!.url.endsWith(".m4a")).toBe(true);
+    expect(existsSync(join(dir, `${song.id}.mp4`))).toBe(false);
+    expect(existsSync(resolved!.url)).toBe(true);
+    expect(statSync(resolved!.url).size).toBeGreaterThan(0);
+    expect(statSync(resolved!.url).size).toBeLessThan(mp4.length);
+  }, 60000);
+
+  it.runIf(have)("extracted audio is still decodable by the player's ffmpeg args", async () => {
+    const p = new LocalMusicProvider(dir);
+    const song = await p.uploadAudio({
+      buffer: render("src2.mp4", withAudio(2, "libx264", "aac")),
+      originalName: "clip.mp4",
+      mimeType: "video/mp4",
+    });
+    const url = (await p.getSongUrl(song.id))!.url;
+
+    const decoded = spawnSync(
+      ffmpeg!,
+      [...buildFfmpegArgs(url, 0).slice(0, -1), "-"],
+      { maxBuffer: 64 * 1024 * 1024 },
+    );
+    expect(decoded.status).toBe(0);
+    // 2s of 48 kHz stereo s16le ≈ 384000 bytes; allow codec priming slack.
+    expect(decoded.stdout.length).toBeGreaterThan(300000);
+  }, 60000);
+
+  it.runIf(have)("aac extraction decodes bit-for-bit identically to the audio inside the video", async () => {
+    // The strongest statement of "lossless": decode the audio track straight
+    // out of the source mp4, decode the stored extract, compare the PCM.
+    // A Matroska remux would NOT pass this — it loses the MP4 edit list that
+    // discards AAC encoder priming, so it decodes ~23 ms longer.
+    const p = new LocalMusicProvider(dir);
+    const bytes = render("bitexact.mp4", withAudio(4, "libx264", "aac"));
+    const sourceCopy = join(dir, "source-kept.mp4");
+    writeFileSync(sourceCopy, bytes);
+
+    const song = await p.uploadAudio({
+      buffer: bytes, originalName: "bitexact.mp4", mimeType: "video/mp4",
+    });
+    const url = (await p.getSongUrl(song.id))!.url;
+
+    const toPcm = (input: string, pre: string[] = []) => spawnSync(
+      ffmpeg!,
+      ["-hide_banner", "-loglevel", "error", "-i", input, ...pre,
+       "-f", "s16le", "-ar", "48000", "-ac", "2", "-acodec", "pcm_s16le", "-"],
+      { maxBuffer: 128 * 1024 * 1024 },
+    );
+
+    const fromVideo = toPcm(sourceCopy, ["-vn", "-map", "0:a:0"]);
+    const fromExtract = toPcm(url);
+    expect(fromVideo.status).toBe(0);
+    expect(fromExtract.status).toBe(0);
+    expect(fromExtract.stdout.length).toBe(fromVideo.stdout.length);
+    expect(fromExtract.stdout.equals(fromVideo.stdout)).toBe(true);
+  }, 90000);
+
+  it.runIf(have)("refuses a video that genuinely has no audio track", async () => {
+    const p = new LocalMusicProvider(dir);
+    const silent = render("silent.mp4", [
+      "-f", "lavfi", "-i", "testsrc=s=160x120:r=10:d=2", "-an",
+    ]);
+    await expect(
+      p.uploadAudio({ buffer: silent, originalName: "silent.mp4", mimeType: "video/mp4" }),
+    ).rejects.toThrow(/音轨/);
+    // The rejected upload must not leave its bytes behind.
+    expect(readdirSync(dir).filter((f) => f.endsWith(".mp4"))).toEqual([]);
+  }, 60000);
+
+  it.runIf(have)("extracts losslessly from avi/mkv/flv too, not just mp4", async () => {
+    const p = new LocalMusicProvider(dir);
+    const cases: Array<[string, string[]]> = [
+      ["a.avi", withAudio(2, "mpeg4", "libmp3lame")],
+      ["a.mkv", withAudio(2, "libx264", "libopus")],
+      ["a.flv", withAudio(2, "flv", "libmp3lame")],
+    ];
+    for (const [name, args] of cases) {
+      const song = await p.uploadAudio({
+        buffer: render(`src-${name}`, args), originalName: name, mimeType: "video/x-msvideo",
+      });
+      const url = (await p.getSongUrl(song.id))!.url;
+      expect(url.endsWith(".mka")).toBe(true);
+      expect(statSync(url).size).toBeGreaterThan(0);
+    }
+  }, 120000);
+
+  it.runIf(have)("a plain audio upload is untouched — no extraction, original extension kept", async () => {
+    const p = new LocalMusicProvider(dir);
+    const mp3 = render("src.mp3", ["-f", "lavfi", "-i", "sine=f=440:d=2", "-c:a", "libmp3lame"]);
+    const song = await p.uploadAudio({ buffer: mp3, originalName: "tune.mp3", mimeType: "audio/mpeg" });
+    const url = (await p.getSongUrl(song.id))!.url;
+    expect(url.endsWith(".mp3")).toBe(true);
+    expect(statSync(url).size).toBe(mp3.length); // byte-identical, not remuxed
+  }, 60000);
+});

src/music/local.ts

@@ -1,5 +1,5 @@
 import { spawn } from "node:child_process";
-import { existsSync, mkdirSync, readFileSync, rmSync, writeFileSync } from "node:fs";
+import { existsSync, mkdirSync, readFileSync, rmSync, statSync, writeFileSync } from "node:fs";
 import { createRequire } from "node:module";
 import path from "node:path";
 import crypto from "node:crypto";
@@ -34,6 +34,56 @@ const AUDIO_EXTENSIONS = new Set([
   ".ape",
 ]);
 
+/** Video containers accepted for upload (#149). Only the audio track is ever
+ *  used — the bot has no video output. Playback would work straight from the
+ *  container (ffmpeg selects the audio stream), but we extract the audio on
+ *  upload so a 200 MB clip does not sit on disk for a 3 MB song; see
+ *  extractAudioTrack. `.webm` is deliberately absent: it is already in
+ *  AUDIO_EXTENSIONS and both audio-only and video .webm are handled there. */
+const VIDEO_EXTENSIONS = new Set([
+  ".mp4",
+  ".mov",
+  ".avi",
+  ".mkv",
+  ".flv",
+  ".wmv",
+  ".m4v",
+  ".mpg",
+  ".mpeg",
+  ".3gp",
+  ".ts",
+  ".m2ts",
+  ".ogv",
+]);
+
+/** Fallback container for an extracted audio track. Matroska takes
+ *  essentially any audio codec, so `-c:a copy` works without knowing what the
+ *  source used — no re-encode, no codec/extension table. */
+const EXTRACTED_AUDIO_EXT = ".mka";
+
+/**
+ * Container to remux an extracted track into, chosen by its codec.
+ *
+ * AAC gets .m4a rather than the Matroska fallback. MP4 stores the AAC encoder
+ * priming (the ~1000 warm-up samples every AAC encoder emits) in an edit list,
+ * and that edit list does NOT survive into Matroska — so an aac→.mka remux
+ * decodes ~23 ms longer than the source, with the priming samples audible at
+ * the head instead of discarded. Measured: −66 dBFS, i.e. inaudible, but the
+ * track is then fractionally out of step with its own reported duration for
+ * no reason. Copying aac into .m4a keeps the edit list and decodes
+ * byte-for-byte identical to the audio inside the original video.
+ *
+ * AAC is worth special-casing because it is what mp4 / mov / m4v — the
+ * formats people actually upload — almost always carry.
+ */
+function extractedAudioExt(codec: string | null): string {
+  return codec === "aac" ? ".m4a" : EXTRACTED_AUDIO_EXT;
+}
+
+function isSupportedUploadExt(ext: string): boolean {
+  return AUDIO_EXTENSIONS.has(ext) || VIDEO_EXTENSIONS.has(ext);
+}
+
 const DEFAULT_MAX_FILES = 200;
 const DEFAULT_MAX_TOTAL_BYTES = 5 * 1024 * 1024 * 1024; // 5 GiB
 
@@ -71,39 +121,130 @@ function titleFromFileName(name: string): string {
   return safeFileName(name).replace(/\.[^.]+$/, "") || "本地音频";
 }
 
-async function probeDurationSeconds(filePath: string): Promise<number> {
+export interface MediaProbe {
+  /** Rounded seconds, 0 when the probe failed or the container has no duration. */
+  durationSeconds: number;
+  /** True when ffmpeg reported at least one audio stream. Only meaningful
+   *  together with `recognized` — see the comment there. */
+  hasAudio: boolean;
+  /** Lowercased codec name of the first audio stream ("aac", "mp3", "opus",
+   *  …), or null when there is none. Picks the remux container. */
+  audioCodec: string | null;
+  /**
+   * True when ffmpeg actually opened the container and printed its
+   * `Input #0, <format>, from '...'` header.
+   *
+   * This is what separates "ffmpeg looked inside and there is genuinely no
+   * audio track" from "ffmpeg could not make sense of these bytes at all".
+   * Both produce hasAudio === false, but only the first is a file we should
+   * refuse. Unreadable bytes have always been accepted here (a truncated mp3
+   * uploads fine and simply reports duration 0), and that stays true.
+   */
+  recognized: boolean;
+  /** False when ffmpeg could not be run or timed out, so nothing else in this
+   *  object is meaningful and the caller must not reject the file on it. */
+  probed: boolean;
+}
+
+/** Parse `Duration: HH:MM:SS.ss`, the `Input #0,` header and
+ *  `Stream #0:N...: Audio:` out of the banner ffmpeg prints on stderr when
+ *  asked to open a file with no output. */
+export function parseMediaProbe(stderr: string): Omit<MediaProbe, "probed"> {
+  const match = stderr.match(/Duration:\s*(\d+):(\d+):(\d+(?:\.\d+)?)/);
+  let durationSeconds = 0;
+  if (match) {
+    const total = Number(match[1]) * 3600 + Number(match[2]) * 60 + Number(match[3]);
+    durationSeconds = Number.isFinite(total) ? Math.round(total) : 0;
+  }
+  // e.g. "  Stream #0:1[0x2](und): Audio: aac (LC) ..." — the stream index and
+  // the bracketed id/language vary, so match on the "Audio:" tag itself. An
+  // embedded cover image is a separate "Video: mjpeg ... [attached pic]" line
+  // and never matches this.
+  const audioMatch = stderr.match(/Stream #\d+:\d+[^\n]*:\s*Audio:\s*([A-Za-z0-9_]+)/);
+  const hasAudio = audioMatch !== null;
+  const audioCodec = audioMatch ? audioMatch[1].toLowerCase() : null;
+  // "Input #0, mov,mp4,m4a,3gp,3g2,mj2, from 'clip.mp4':" — absent entirely
+  // when ffmpeg bails with "Error opening input: Invalid data found ...".
+  const recognized = /^Input #\d+,/m.test(stderr);
+  return { durationSeconds, hasAudio, audioCodec, recognized };
+}
+
+async function probeMedia(filePath: string): Promise<MediaProbe> {
   return new Promise((resolve) => {
     const ffmpeg = spawn(ffmpegPath || "ffmpeg", ["-hide_banner", "-i", filePath], {
       stdio: ["ignore", "ignore", "pipe"],
     });
     let stderr = "";
+    let settled = false;
+    const done = (probe: MediaProbe) => {
+      if (settled) return;
+      settled = true;
+      resolve(probe);
+    };
+    // Video containers are much larger than the audio files this used to see,
+    // and the probe only reads headers — but a network/USB path can still be
+    // slow, so allow more than the old 5s before giving up.
     const timeout = setTimeout(() => {
       ffmpeg.kill("SIGKILL");
-      resolve(0);
-    }, 5000);
+      done({ durationSeconds: 0, hasAudio: false, audioCodec: null, recognized: false, probed: false });
+    }, 20000);
     ffmpeg.stderr.on("data", (chunk) => {
       stderr += chunk.toString("utf8");
     });
     ffmpeg.on("error", () => {
       clearTimeout(timeout);
-      resolve(0);
+      done({ durationSeconds: 0, hasAudio: false, audioCodec: null, recognized: false, probed: false });
     });
     ffmpeg.on("close", () => {
       clearTimeout(timeout);
-      const match = stderr.match(/Duration:\s*(\d+):(\d+):(\d+(?:\.\d+)?)/);
-      if (!match) {
-        resolve(0);
-        return;
-      }
-      const hours = Number(match[1]);
-      const minutes = Number(match[2]);
-      const seconds = Number(match[3]);
-      const total = hours * 3600 + minutes * 60 + seconds;
-      resolve(Number.isFinite(total) ? Math.round(total) : 0);
+      done({ ...parseMediaProbe(stderr), probed: true });
     });
   });
 }
 
+/**
+ * Remux the first audio stream of `source` into `target` (#149).
+ *
+ * `-c:a copy` — the audio is moved bit-for-bit into a Matroska audio
+ * container, so this is fast, lossless, and codec-agnostic. Nothing is
+ * re-encoded, so a 200 MB .mp4 becomes a few MB .mka with the original audio
+ * intact. Video, subtitle and data streams are dropped.
+ *
+ * Returns true only if ffmpeg exited 0 AND produced a non-empty file, so a
+ * partial/zero-byte result can never be mistaken for a successful extraction.
+ * Callers fall back to keeping the original container, which plays fine.
+ */
+async function extractAudioTrack(source: string, target: string): Promise<boolean> {
+  const ok = await new Promise<boolean>((resolve) => {
+    const ffmpeg = spawn(
+      ffmpegPath || "ffmpeg",
+      ["-hide_banner", "-loglevel", "error", "-y", "-i", source,
+       "-vn", "-sn", "-dn", "-map", "0:a:0", "-c:a", "copy", target],
+      { stdio: ["ignore", "ignore", "ignore"] },
+    );
+    let settled = false;
+    const done = (v: boolean) => {
+      if (settled) return;
+      settled = true;
+      resolve(v);
+    };
+    // Remuxing is I/O bound, but a multi-GB input on a slow disk still takes
+    // a while. Cap it so a pathological file cannot wedge the upload request.
+    const timeout = setTimeout(() => {
+      ffmpeg.kill("SIGKILL");
+      done(false);
+    }, 120000);
+    ffmpeg.on("error", () => { clearTimeout(timeout); done(false); });
+    ffmpeg.on("close", (code) => { clearTimeout(timeout); done(code === 0); });
+  });
+  if (!ok) return false;
+  try {
+    return statSync(target).size > 0;
+  } catch {
+    return false;
+  }
+}
+
 export class LocalMusicProvider implements MusicProvider {
   readonly platform = "local" as const;
   private readonly uploadDir: string;
@@ -171,33 +312,91 @@ export class LocalMusicProvider implements MusicProvider {
     const ext = path.extname(originalName).toLowerCase();
     // Validate by the (sanitised) file extension only — never trust the
     // client-supplied Content-Type. This also guarantees the STORED extension
-    // is one of the known audio types, so a spoofed header cannot persist an
-    // arbitrary-extension blob on disk.
-    if (!AUDIO_EXTENSIONS.has(ext)) {
-      throw new Error("只支持常见音频文件，如 mp3、flac、wav、m4a、ogg、opus、aac、webm 等");
+    // is one of the known audio/video types, so a spoofed header cannot
+    // persist an arbitrary-extension blob on disk.
+    if (!isSupportedUploadExt(ext)) {
+      throw new Error(
+        "只支持常见音频文件（mp3、flac、wav、m4a、ogg、opus、aac、webm 等）" +
+        "和视频文件（mp4、mov、avi、mkv、flv、wmv 等，仅取其中的音轨播放）",
+      );
     }
     if (!input.buffer || input.buffer.length === 0) {
       throw new Error("上传文件为空");
     }
 
     const id = crypto.randomUUID();
-    const storedName = `${id}${ext}`;
-    const filePath = path.join(this.uploadDir, storedName);
+    const isVideo = VIDEO_EXTENSIONS.has(ext);
+    let filePath = path.join(this.uploadDir, `${id}${ext}`);
     writeFileSync(filePath, input.buffer);
 
-    const duration = await probeDurationSeconds(filePath);
+    let probe: MediaProbe;
+    try {
+      probe = await probeMedia(filePath);
+    } catch {
+      probe = { durationSeconds: 0, hasAudio: false, audioCodec: null, recognized: false, probed: false };
+    }
+
+    // Reject a video with no audio track up front (#149). Left to playback it
+    // would produce a silent, zero-byte stream that just looks like a broken
+    // song. Require `recognized` as well as `probed`: bytes ffmpeg cannot open
+    // at all report hasAudio false for a different reason, and those have
+    // always been accepted (a truncated upload lands with duration 0) — this
+    // change must not start rejecting them.
+    if (isVideo && probe.probed && probe.recognized && !probe.hasAudio) {
+      rmSync(filePath, { force: true });
+      throw new Error("这个视频里没有音轨，无法播放");
+    }
+
+    let size = input.buffer.length;
+    if (isVideo) {
+      // Keep only the audio. The video bytes are dead weight against the
+      // upload-directory quota and would never be used.
+      // Preferred container first; if that remux fails (a codec the container
+      // will not take), retry into Matroska, which takes almost anything.
+      const preferredExt = extractedAudioExt(probe.audioCodec);
+      let extracted = path.join(this.uploadDir, `${id}${preferredExt}`);
+      let ok = await extractAudioTrack(filePath, extracted);
+      if (!ok && preferredExt !== EXTRACTED_AUDIO_EXT) {
+        rmSync(extracted, { force: true });
+        extracted = path.join(this.uploadDir, `${id}${EXTRACTED_AUDIO_EXT}`);
+        ok = await extractAudioTrack(filePath, extracted);
+      }
+      if (ok) {
+        try {
+          // Commit filePath and size TOGETHER, and only after the source is
+          // actually gone. rmSync(force) still throws EBUSY/EPERM on Windows,
+          // and assigning size first would leave the record claiming the
+          // small extracted size while still pointing at the whole video —
+          // which makes totalBytes() under-count and lets the upload
+          // directory grow past its quota.
+          const extractedSize = statSync(extracted).size;
+          rmSync(filePath, { force: true });
+          filePath = extracted;
+          size = extractedSize;
+        } catch {
+          // Could not stat/remove (Windows lock) — keep playing the original
+          // container and drop the half-finished extract.
+          rmSync(extracted, { force: true });
+        }
+      } else {
+        // Extraction failed (exotic codec Matroska won't take, timeout, …).
+        // The original container still plays: ffmpeg picks its audio stream.
+        rmSync(extracted, { force: true });
+      }
+    }
+
     const song: LocalSongRecord = {
       id,
       name: titleFromFileName(originalName),
       artist: "本地上传",
       album: "本地音乐",
-      duration,
+      duration: probe.durationSeconds,
       coverUrl: "",
       platform: "local",
       filePath,
       originalName,
       uploadedAt: new Date().toISOString(),
-      size: input.buffer.length,
+      size,
       mimeType: input.mimeType || "application/octet-stream",
     };
 
@@ -214,12 +413,12 @@ export class LocalMusicProvider implements MusicProvider {
     return song;
   }
 
-  async search(query: string, limit = 20): Promise<SearchResult> {
+  async search(query: string, limit = 20, offset = 0): Promise<SearchResult> {
     const q = query.trim().toLowerCase();
     const songs = this.records
       .filter((r) => existsSync(r.filePath))
       .filter((r) => !q || `${r.name} ${r.artist} ${r.album} ${r.originalName}`.toLowerCase().includes(q))
-      .slice(0, limit)
+      .slice(offset, offset + limit)
       .map((r) => this.toSong(r));
     return { songs, playlists: [], albums: [] };
   }

src/music/netease.test.ts

@@ -1,5 +1,5 @@
-import { describe, it, expect } from "vitest";
-import { parseLyrics, mapNeteaseAlbums, mapNeteaseSongs, parseNeteaseTrial } from "./netease.js";
+import { describe, it, expect, vi } from "vitest";
+import { parseLyrics, mapNeteaseAlbums, mapNeteaseSongs, parseNeteaseTrial, NeteaseProvider } from "./netease.js";
 
 describe("NetEase adapter", () => {
   it("parses LRC format lyrics", () => {
@@ -93,3 +93,49 @@ describe("NetEase adapter", () => {
     expect(parseNeteaseTrial({ freeTrialInfo: { start: 0, end: 0 } })).toBeUndefined();
   });
 });
+
+describe("NeteaseProvider.search pagination", () => {
+  function mockProvider() {
+    const p = new NeteaseProvider("http://x");
+    const get = vi.fn().mockResolvedValue({
+      data: { result: { songs: [], playlists: [], albums: [] } },
+    });
+    (p as any).api = { get };
+    return { p, get };
+  }
+
+  /** Find the /cloudsearch call whose params.type matches. */
+  function callByType(get: ReturnType<typeof vi.fn>, type: number) {
+    const call = get.mock.calls.find((c: any[]) => c[1]?.params?.type === type);
+    expect(call, `expected a /cloudsearch call with type=${type}`).toBeTruthy();
+    return call![1].params as Record<string, unknown>;
+  }
+
+  it("forwards offset for songs and uses real limit+offset for playlists/albums", async () => {
+    const { p, get } = mockProvider();
+    await p.search("hello", 20, 20);
+
+    // songs (type 1): offset forwarded, limit unchanged
+    const songs = callByType(get, 1);
+    expect(songs.limit).toBe(20);
+    expect(songs.offset).toBe(20);
+
+    // playlists (type 1000): limit-driven (NOT hardcoded 10) + offset
+    const playlists = callByType(get, 1000);
+    expect(playlists.limit).toBe(20);
+    expect(playlists.offset).toBe(20);
+
+    // albums (type 10): limit-driven (NOT hardcoded 10) + offset
+    const albums = callByType(get, 10);
+    expect(albums.limit).toBe(20);
+    expect(albums.offset).toBe(20);
+  });
+
+  it("defaults offset to 0 (backward compatible)", async () => {
+    const { p, get } = mockProvider();
+    await p.search("hello", 20);
+    expect(callByType(get, 1).offset).toBe(0);
+    expect(callByType(get, 1000).offset).toBe(0);
+    expect(callByType(get, 10).offset).toBe(0);
+  });
+});

src/music/netease.ts

@@ -131,21 +131,25 @@ export class NeteaseProvider implements MusicProvider {
     return this.cookie ? { cookie: this.cookie } : {};
   }
 
-  async search(query: string, limit = 20): Promise<SearchResult> {
+  async search(query: string, limit = 20, offset = 0): Promise<SearchResult> {
+    // /cloudsearch supports offset for every type. Songs, playlists (type 1000)
+    // and albums (type 10) are all limit/offset-driven so the web can page past
+    // the first page (playlists/albums were previously hardcoded to limit: 10).
     const [songRes, playlistRes, albumRes] = await Promise.all([
       this.api.get("/cloudsearch", {
-        params: { keywords: query, type: 1, limit, ...this.cookieParams },
+        params: { keywords: query, type: 1, limit, offset, ...this.cookieParams },
       }),
       this.api.get("/cloudsearch", {
         params: {
           keywords: query,
           type: 1000,
-          limit: 10,
+          limit,
+          offset,
           ...this.cookieParams,
         },
       }),
       this.api.get("/cloudsearch", {
-        params: { keywords: query, type: 10, limit: 10, ...this.cookieParams },
+        params: { keywords: query, type: 10, limit, offset, ...this.cookieParams },
       }),
     ]);
 

src/music/provider.ts

@@ -1,3 +1,15 @@
+/** All music source platforms. Jellyfin ItemIds are GUID strings — never
+ *  assume numeric ids when handling a generic Platform. */
+export type Platform =
+  | "netease"
+  | "qq"
+  | "bilibili"
+  | "youtube"
+  | "local"
+  | "kugou"
+  | "spotify"
+  | "jellyfin";
+
 export interface Song {
   id: string;
   name: string;
@@ -5,7 +17,7 @@ export interface Song {
   album: string;
   duration: number; // seconds
   coverUrl: string;
-  platform: "netease" | "qq" | "bilibili" | "youtube" | "local";
+  platform: Platform;
   /** VIP / copyright-restricted: non-VIP users can only play a trial fragment
    *  (NetEase fee=1 VIP / fee=4 album-only, or QQ pay.payplay/paytrackprice=1). */
   vip?: boolean;
@@ -27,7 +39,7 @@ export interface Playlist {
   name: string;
   coverUrl: string;
   songCount: number;
-  platform: "netease" | "qq" | "bilibili" | "youtube" | "local";
+  platform: Platform;
 }
 
 export interface PlaylistDetail {
@@ -44,7 +56,7 @@ export interface Album {
   artist: string;
   coverUrl: string;
   songCount: number;
-  platform: "netease" | "qq" | "bilibili" | "youtube" | "local";
+  platform: Platform;
 }
 
 export interface LyricLine {
@@ -72,9 +84,9 @@ export interface AuthStatus {
 }
 
 export interface MusicProvider {
-  readonly platform: "netease" | "qq" | "bilibili" | "youtube" | "local";
+  readonly platform: Platform;
 
-  search(query: string, limit?: number): Promise<SearchResult>;
+  search(query: string, limit?: number, offset?: number): Promise<SearchResult>;
   getSongUrl(songId: string, quality?: string): Promise<SongUrlResult | null>;
   setQuality(quality: string): void;
   getQuality(): string;

src/music/qq.test.ts

@@ -1,5 +1,14 @@
-import { describe, it, expect } from "vitest";
-import { mapQqAlbums, mapQqSongs, parseQqTrial } from "./qq.js";
+import { describe, it, expect, vi, beforeEach } from "vitest";
+
+// All axios.create(...) instances in qq.ts (qqMusicuApi / qqSearchApi / qqFavApi
+// and the per-instance api) share this single mock so the search test can
+// inspect the outgoing params/body regardless of which client issued them.
+const { mockGet, mockPost } = vi.hoisted(() => ({ mockGet: vi.fn(), mockPost: vi.fn() }));
+vi.mock("axios", () => ({
+  default: { create: () => ({ get: mockGet, post: mockPost }) },
+}));
+
+import { mapQqAlbums, mapQqSongs, parseQqTrial, QQMusicProvider } from "./qq.js";
 
 describe("QQ adapter", () => {
   it("mapQqSongs maps QQMusicApi-style song entries", () => {
@@ -92,3 +101,74 @@ describe("QQ adapter", () => {
     expect(out[0].id).toBe("");
   });
 });
+
+describe("QQMusicProvider.search pagination", () => {
+  beforeEach(() => {
+    mockGet.mockReset();
+    mockPost.mockReset();
+  });
+
+  /** musicu.fcg returns one song → primary path succeeds. */
+  function musicuOk() {
+    mockGet.mockImplementation(async (url: string) => {
+      if (url === "/cgi-bin/musicu.fcg") {
+        return {
+          data: {
+            req_0: { data: { body: { song: { list: [{ mid: "m1", name: "S", singer: [], album: {}, interval: 100 }] } } } },
+            req_album: { data: { body: { album: { list: [] } } } },
+            req_playlist: { data: { body: { songlist: { list: [] } } } },
+          },
+        };
+      }
+      return { data: {} };
+    });
+  }
+
+  function musicuReqData() {
+    const call = mockGet.mock.calls.find((c: any[]) => c[0] === "/cgi-bin/musicu.fcg");
+    expect(call, "expected a musicu.fcg call").toBeTruthy();
+    return JSON.parse(call![1].params.data);
+  }
+
+  it("adds page_num (offset/limit+1) and limit-driven num_per_page for songs/albums/playlists", async () => {
+    musicuOk();
+    const p = new QQMusicProvider("http://x");
+    await p.search("hello", 20, 20); // page 2
+
+    const d = musicuReqData();
+    expect(d.req_0.param.page_num).toBe(2);
+    expect(d.req_0.param.num_per_page).toBe(20);
+    // Albums/playlists: num_per_page must be limit-driven (NOT hardcoded 10).
+    expect(d.req_album.param.page_num).toBe(2);
+    expect(d.req_album.param.num_per_page).toBe(20);
+    expect(d.req_playlist.param.page_num).toBe(2);
+    expect(d.req_playlist.param.num_per_page).toBe(20);
+  });
+
+  it("defaults offset to 0 → page_num 1 (backward compatible)", async () => {
+    musicuOk();
+    const p = new QQMusicProvider("http://x");
+    await p.search("hello", 20);
+    const d = musicuReqData();
+    expect(d.req_0.param.page_num).toBe(1);
+  });
+
+  it("fallback client_search_cp sets p to the page cursor", async () => {
+    // musicu returns no songs → primary returns null → fallback runs.
+    mockGet.mockImplementation(async (url: string) => {
+      if (url === "/cgi-bin/musicu.fcg") {
+        return { data: { req_0: { data: { body: { song: { list: [] } } } } } };
+      }
+      // client_search_cp
+      return { data: { data: { song: { list: [] }, album: { list: [] } } } };
+    });
+    const p = new QQMusicProvider("http://x");
+    await p.search("hello", 20, 20); // page 2
+
+    const songCall = mockGet.mock.calls.find(
+      (c: any[]) => c[0] === "/soso/fcgi-bin/client_search_cp" && c[1]?.params?.type === 0
+    );
+    expect(songCall, "expected a client_search_cp song call").toBeTruthy();
+    expect(songCall![1].params.p).toBe(2);
+  });
+});

src/music/qq.ts

@@ -149,16 +149,16 @@ export class QQMusicProvider implements MusicProvider {
     };
   }
 
-  async search(query: string, limit = 20): Promise<SearchResult> {
+  async search(query: string, limit = 20, offset = 0): Promise<SearchResult> {
     // Primary: u.y.qq.com/cgi-bin/musicu.fcg — supports songs + albums +
     // playlists. Fixed per https://github.com/ZHANGTIANYAO1/teamspeak-music-bot/issues/61
     // (removed searchid, num_per_page >= 10, corrected search_type values).
-    const primary = await this.searchViaMusicuFcg(query, limit);
+    const primary = await this.searchViaMusicuFcg(query, limit, offset);
     if (primary) return primary;
 
     // Fallback: c.y.qq.com/soso/fcgi-bin/client_search_cp (song + album,
     // no playlist support). Kept as redundancy.
-    return this.searchViaClientSearchCp(query, limit);
+    return this.searchViaClientSearchCp(query, limit, offset);
   }
 
   /** Primary search via u.y.qq.com/cgi-bin/musicu.fcg.
@@ -169,25 +169,31 @@ export class QQMusicProvider implements MusicProvider {
    *   3. `search_type: 2` for albums, `3` for playlists (8 was "user"). */
   private async searchViaMusicuFcg(
     query: string,
-    limit: number
+    limit: number,
+    offset = 0
   ): Promise<SearchResult | null> {
     try {
+      // num_per_page must stay >= 10 (lower values return empty). It is now
+      // limit-driven for ALL three lists (albums/playlists were hardcoded to
+      // 10). page_num is the offset cursor; the web always requests in
+      // limit-aligned pages so offset is a multiple of limit.
       const numPerPage = Math.max(10, Math.min(limit, 50));
+      const pageNum = Math.floor(offset / limit) + 1;
       const reqData = JSON.stringify({
         req_0: {
           module: "music.search.SearchCgiService",
           method: "DoSearchForQQMusicDesktop",
-          param: { query, num_per_page: numPerPage, search_type: 0 },
+          param: { query, num_per_page: numPerPage, page_num: pageNum, search_type: 0 },
         },
         req_album: {
           module: "music.search.SearchCgiService",
           method: "DoSearchForQQMusicDesktop",
-          param: { query, num_per_page: 10, search_type: 2 },
+          param: { query, num_per_page: numPerPage, page_num: pageNum, search_type: 2 },
         },
         req_playlist: {
           module: "music.search.SearchCgiService",
           method: "DoSearchForQQMusicDesktop",
-          param: { query, num_per_page: 10, search_type: 3 },
+          param: { query, num_per_page: numPerPage, page_num: pageNum, search_type: 3 },
         },
       });
       const res = await qqMusicuApi.get("/cgi-bin/musicu.fcg", {
@@ -221,12 +227,16 @@ export class QQMusicProvider implements MusicProvider {
   /** Fallback search via c.y.qq.com/soso/fcgi-bin/client_search_cp */
   private async searchViaClientSearchCp(
     query: string,
-    limit: number
+    limit: number,
+    offset = 0
   ): Promise<SearchResult> {
+    // `p` is the 1-based page cursor. The web pages in limit-aligned steps so
+    // offset is a multiple of limit.
+    const page = Math.floor(offset / limit) + 1;
     const songParams = {
       w: query,
       format: "json",
-      p: 1,
+      p: page,
       n: Math.min(limit, 50),
       type: 0,
       cr: 1,
@@ -234,7 +244,7 @@ export class QQMusicProvider implements MusicProvider {
     const albumParams = {
       w: query,
       format: "json",
-      p: 1,
+      p: page,
       n: 5,
       t: 8,
       cr: 1,
@@ -354,8 +364,18 @@ export class QQMusicProvider implements MusicProvider {
         };
       }
     } catch {
-      // fall through to stub
+      // fall through to musicu.fcg fallback
     }
+
+    // Fallback: fetch metadata via u.y.qq.com/cgi-bin/musicu.fcg. The bundled
+    // library's /getSongInfo route is broken (upstream code 500001), so the
+    // primary try above almost always falls through here for QQ. Without this,
+    // play-by-id songs carry an empty name → the TS nickname / now-playing
+    // message renders as "♪ 正在播放:  -  []". This endpoint (same host/shape
+    // as search) reliably returns full track_info without requiring login.
+    const detail = await this.fetchSongDetailViaMusicu(songId);
+    if (detail) return detail;
+
     // Minimal stub — resolveAndPlay only needs id + platform to fetch a
     // play URL. Name/artist/album will be empty in play history, but the
     // song will actually play, which is the important part.
@@ -370,6 +390,42 @@ export class QQMusicProvider implements MusicProvider {
     };
   }
 
+  /** Fetch a single song's metadata via u.y.qq.com/cgi-bin/musicu.fcg
+   * (module music.pf_song_detail_svr / get_song_detail_yqq). This mirrors the
+   * search path's host + request shape and, unlike the library's /getSongInfo,
+   * actually works against QQ's current API. Returns null on any failure so the
+   * caller can fall back to the minimal stub. */
+  private async fetchSongDetailViaMusicu(songId: string): Promise<Song | null> {
+    try {
+      const reqData = JSON.stringify({
+        req_0: {
+          module: "music.pf_song_detail_svr",
+          method: "get_song_detail_yqq",
+          param: { song_mid: songId, song_type: 0 },
+        },
+      });
+      const res = await qqMusicuApi.get("/cgi-bin/musicu.fcg", {
+        params: { format: "json", data: reqData },
+      });
+      const t = res.data?.req_0?.data?.track_info;
+      if (!t) return null;
+      const albumMid = t.album?.mid ?? t.album?.pmid ?? "";
+      return {
+        id: String(t.mid ?? t.id ?? songId),
+        name: t.name ?? t.title ?? "",
+        artist: (t.singer ?? []).map((a: any) => a.name ?? a.title ?? "").filter(Boolean).join(" / "),
+        album: t.album?.name ?? t.album?.title ?? "",
+        duration: t.interval ?? 0,
+        coverUrl: albumMid
+          ? `https://y.gtimg.cn/music/photo_new/T002R300x300M000${albumMid}.jpg`
+          : "",
+        platform: "qq",
+      };
+    } catch {
+      return null;
+    }
+  }
+
   async getPlaylistSongs(playlistId: string): Promise<Song[]> {
     const res = await this.api.get("/getSongListDetail", {
       params: { disstid: playlistId, ...this.cookieParams },

src/music/spotify/backend-select.test.ts

@@ -0,0 +1,12 @@
+import { describe, it, expect } from "vitest";
+import { resolveSpotifyBackendKind as pick } from "./backend-select.js";
+describe("resolveSpotifyBackendKind", () => {
+  it("auto: go present -> go-librespot", () => expect(pick("auto", true, true)).toBe("go-librespot"));
+  it("auto: go absent, rust present -> librespot", () => expect(pick("auto", false, true)).toBe("librespot"));
+  it("auto: neither -> null", () => expect(pick("auto", false, false)).toBeNull());
+  it("go-librespot: present -> go-librespot", () => expect(pick("go-librespot", true, true)).toBe("go-librespot"));
+  it("go-librespot: absent -> null even if rust present", () => expect(pick("go-librespot", false, true)).toBeNull());
+  it("librespot: present -> librespot", () => expect(pick("librespot", true, true)).toBe("librespot"));
+  it("librespot: absent -> null even if go present", () => expect(pick("librespot", true, false)).toBeNull());
+  it("auto default fallthrough matches auto", () => expect(pick("auto", true, false)).toBe("go-librespot"));
+});

src/music/spotify/backend-select.ts

@@ -0,0 +1,25 @@
+/** Which concrete backend runs for a given config + host binary availability. */
+export type SpotifyBackendKind = "go-librespot" | "librespot";
+
+/**
+ * Pure backend selection shared by SpotifyController.chooseBackend() (per-bot)
+ * and the web /status endpoint (process-wide). Booleans in, no IO — the caller
+ * supplies platform+binary presence.
+ */
+export function resolveSpotifyBackendKind(
+  backend: "auto" | "go-librespot" | "librespot",
+  goPresent: boolean,
+  rustPresent: boolean,
+): SpotifyBackendKind | null {
+  switch (backend) {
+    case "go-librespot":
+      return goPresent ? "go-librespot" : null;
+    case "librespot":
+      return rustPresent ? "librespot" : null;
+    case "auto":
+    default:
+      if (goPresent) return "go-librespot";
+      if (rustPresent) return "librespot";
+      return null;
+  }
+}

src/music/spotify/backend.ts

@@ -0,0 +1,41 @@
+// src/music/spotify/backend.ts
+// Type contract for the Spotify audio backend (go-librespot sidecar).
+// Interface-only: this module intentionally contains NO runtime code so it
+// can be imported for types by go-librespot.ts and controller.ts without
+// pulling in child_process/ws/ffmpeg at type-check time.
+
+/** Emitted when the currently playing Spotify track finishes or is stopped. */
+export interface SpotifyTrackEndedEvent {
+  uri: string;
+  reason: "ended" | "stopped" | "error";
+}
+
+/** Now-playing metadata surfaced from the go-librespot "metadata" event. */
+export interface SpotifyNowPlaying {
+  uri: string;
+  name: string;
+  artist: string;
+  album: string;
+  coverUrl: string;
+  durationMs: number;
+}
+
+/**
+ * Long-lived Spotify audio source: owns the go-librespot sidecar + FIFO->ffmpeg
+ * PCM pipe and exposes transport control plus a continuous 48kHz s16le stereo
+ * PCM stream to feed AudioPlayer.playPcmStream().
+ */
+export interface SpotifyAudioBackend {
+  start(): Promise<void>;
+  stop(): void;
+  isReady(): boolean;
+  playTrack(uri: string): Promise<void>;
+  pause(): Promise<void>;
+  resume(): Promise<void>;
+  seek(ms: number): Promise<void>;
+  getPcmStream(): import("node:stream").Readable;
+  getPositionMs(): number;
+  on(event: "trackEnded", cb: (e: SpotifyTrackEndedEvent) => void): void;
+  on(event: "metadata", cb: (m: SpotifyNowPlaying) => void): void;
+  on(event: "ready" | "error", cb: (arg?: unknown) => void): void;
+}

src/music/spotify/binary.test.ts

@@ -0,0 +1,363 @@
+import { describe, it, expect, vi, afterEach } from "vitest";
+import { join } from "node:path";
+import { mkdtempSync, writeFileSync, rmSync } from "node:fs";
+import { tmpdir } from "node:os";
+import {
+  isGoLibrespotSupported,
+  pickGoLibrespotPath,
+  findGoLibrespot,
+  checkGoLibrespotAvailable,
+  resetGoLibrespotBinaryCache,
+  __setGoLibrespotVersionProbe,
+  isRustLibrespotSupported,
+  pickLibrespotPath,
+  findLibrespot,
+  checkLibrespotAvailable,
+  resetLibrespotBinaryCache,
+  __setLibrespotVersionProbe,
+  resolveExecutable,
+  isLibrespotPresent,
+  isGoLibrespotPresent,
+} from "./binary.js";
+
+const origPlatform = process.platform;
+function setPlatform(p: NodeJS.Platform): void {
+  Object.defineProperty(process, "platform", { value: p, configurable: true });
+}
+
+// Snapshot the PATH env so PATH-resolution tests can point it at temp dirs and
+// restore afterwards. PATHEXT is optional (undefined on posix); track presence.
+const origPath = process.env.PATH;
+const origPathExt = process.env.PATHEXT;
+const tmpDirs: string[] = [];
+function mkTmpDir(prefix: string): string {
+  const dir = mkdtempSync(join(tmpdir(), prefix));
+  tmpDirs.push(dir);
+  return dir;
+}
+
+afterEach(() => {
+  setPlatform(origPlatform);
+  __setGoLibrespotVersionProbe(null);
+  resetGoLibrespotBinaryCache();
+  __setLibrespotVersionProbe(null);
+  resetLibrespotBinaryCache();
+  process.env.PATH = origPath;
+  if (origPathExt === undefined) delete process.env.PATHEXT;
+  else process.env.PATHEXT = origPathExt;
+  for (const dir of tmpDirs.splice(0)) {
+    try {
+      rmSync(dir, { recursive: true, force: true });
+    } catch {
+      /* ignore */
+    }
+  }
+});
+
+describe("isGoLibrespotSupported", () => {
+  it("is true only on linux", () => {
+    setPlatform("linux");
+    expect(isGoLibrespotSupported()).toBe(true);
+    setPlatform("win32");
+    expect(isGoLibrespotSupported()).toBe(false);
+    setPlatform("darwin");
+    expect(isGoLibrespotSupported()).toBe(false);
+  });
+});
+
+describe("pickGoLibrespotPath (bin/ then PATH ordering)", () => {
+  const binPath = join("some", "root", "bin", "go-librespot");
+
+  it("prefers the bin/ path when the file exists", () => {
+    expect(
+      pickGoLibrespotPath([binPath, "go-librespot"], (p) => p === binPath),
+    ).toBe(binPath);
+  });
+
+  it("falls through to the bare PATH name when the bin/ file is missing", () => {
+    expect(pickGoLibrespotPath([binPath, "go-librespot"], () => false)).toBe(
+      "go-librespot",
+    );
+  });
+
+  it("returns bare command names without touching the filesystem", () => {
+    const exists = vi.fn(() => false);
+    expect(pickGoLibrespotPath(["go-librespot"], exists)).toBe("go-librespot");
+    expect(exists).not.toHaveBeenCalled();
+  });
+});
+
+describe("findGoLibrespot", () => {
+  it("returns the bare command name when bin/go-librespot is absent", () => {
+    // No go-librespot binary is committed under bin/, so resolution must
+    // fall back to the bare PATH name (execFile resolves it at run time).
+    expect(findGoLibrespot()).toBe("go-librespot");
+  });
+});
+
+describe("checkGoLibrespotAvailable", () => {
+  it("returns false immediately on unsupported platforms without probing", async () => {
+    setPlatform("darwin");
+    const probe = vi.fn(async () => {});
+    __setGoLibrespotVersionProbe(probe);
+    expect(await checkGoLibrespotAvailable()).toBe(false);
+    expect(probe).not.toHaveBeenCalled();
+  });
+
+  it("returns true when the binary responds to --version on linux", async () => {
+    setPlatform("linux");
+    __setGoLibrespotVersionProbe(async () => {});
+    expect(await checkGoLibrespotAvailable()).toBe(true);
+  });
+
+  it("caches only positive results and probes once", async () => {
+    setPlatform("linux");
+    const probe = vi.fn(async () => {});
+    __setGoLibrespotVersionProbe(probe);
+    expect(await checkGoLibrespotAvailable()).toBe(true);
+    expect(await checkGoLibrespotAvailable()).toBe(true);
+    expect(probe).toHaveBeenCalledTimes(1);
+  });
+
+  it("does not cache a failed probe (retries on the next call)", async () => {
+    setPlatform("linux");
+    __setGoLibrespotVersionProbe(async () => {
+      throw new Error("ENOENT");
+    });
+    expect(await checkGoLibrespotAvailable()).toBe(false);
+    // A later successful probe must now succeed — negatives are not cached.
+    __setGoLibrespotVersionProbe(async () => {});
+    expect(await checkGoLibrespotAvailable()).toBe(true);
+  });
+
+  it("resetGoLibrespotBinaryCache clears a cached positive", async () => {
+    setPlatform("linux");
+    __setGoLibrespotVersionProbe(async () => {});
+    expect(await checkGoLibrespotAvailable()).toBe(true);
+    resetGoLibrespotBinaryCache();
+    __setGoLibrespotVersionProbe(async () => {
+      throw new Error("gone");
+    });
+    expect(await checkGoLibrespotAvailable()).toBe(false);
+  });
+});
+
+describe("isRustLibrespotSupported", () => {
+  it("is true on every platform (pipe->stdout works everywhere)", () => {
+    setPlatform("linux");
+    expect(isRustLibrespotSupported()).toBe(true);
+    setPlatform("win32");
+    expect(isRustLibrespotSupported()).toBe(true);
+    setPlatform("darwin");
+    expect(isRustLibrespotSupported()).toBe(true);
+  });
+});
+
+describe("pickLibrespotPath (bin/ then PATH ordering, win32 exe)", () => {
+  it("prefers the bin/ path when the file exists", () => {
+    const binPath = join("some", "root", "bin", "librespot");
+    expect(
+      pickLibrespotPath([binPath, "librespot"], (p) => p === binPath),
+    ).toBe(binPath);
+  });
+
+  it("prefers the bin/librespot.exe path on win32 when it exists", () => {
+    setPlatform("win32");
+    const binExe = join("some", "root", "bin", "librespot.exe");
+    expect(
+      pickLibrespotPath([binExe, "librespot.exe"], (p) => p === binExe),
+    ).toBe(binExe);
+  });
+
+  it("falls through to the bare PATH name (librespot) on posix when bin/ is missing", () => {
+    setPlatform("linux");
+    const binPath = join("some", "root", "bin", "librespot");
+    expect(pickLibrespotPath([binPath, "librespot"], () => false)).toBe(
+      "librespot",
+    );
+  });
+
+  it("falls through to librespot.exe on win32 when bin/ is missing", () => {
+    setPlatform("win32");
+    const binExe = join("some", "root", "bin", "librespot.exe");
+    expect(pickLibrespotPath([binExe], () => false)).toBe("librespot.exe");
+  });
+
+  it("returns bare command names without touching the filesystem", () => {
+    const exists = vi.fn(() => false);
+    expect(pickLibrespotPath(["librespot"], exists)).toBe("librespot");
+    expect(exists).not.toHaveBeenCalled();
+  });
+});
+
+describe("findLibrespot", () => {
+  it("returns the bare command name when bin/librespot is absent", () => {
+    // No librespot binary is committed under bin/, so resolution must fall
+    // back to the bare PATH name (execFile resolves it at run time).
+    setPlatform("linux");
+    expect(findLibrespot()).toBe("librespot");
+  });
+
+  it("returns librespot.exe on win32 when bin/librespot.exe is absent", () => {
+    setPlatform("win32");
+    expect(findLibrespot()).toBe("librespot.exe");
+  });
+});
+
+describe("checkLibrespotAvailable", () => {
+  it("returns true when the binary responds to --version (any platform)", async () => {
+    setPlatform("win32");
+    __setLibrespotVersionProbe(async () => {});
+    expect(await checkLibrespotAvailable()).toBe(true);
+  });
+
+  it("returns true on darwin too (no platform gate)", async () => {
+    setPlatform("darwin");
+    __setLibrespotVersionProbe(async () => {});
+    expect(await checkLibrespotAvailable()).toBe(true);
+  });
+
+  it("caches only positive results and probes once", async () => {
+    setPlatform("linux");
+    const probe = vi.fn(async () => {});
+    __setLibrespotVersionProbe(probe);
+    expect(await checkLibrespotAvailable()).toBe(true);
+    expect(await checkLibrespotAvailable()).toBe(true);
+    expect(probe).toHaveBeenCalledTimes(1);
+  });
+
+  it("does not cache a failed probe (retries on the next call)", async () => {
+    setPlatform("win32");
+    __setLibrespotVersionProbe(async () => {
+      throw new Error("ENOENT");
+    });
+    expect(await checkLibrespotAvailable()).toBe(false);
+    __setLibrespotVersionProbe(async () => {});
+    expect(await checkLibrespotAvailable()).toBe(true);
+  });
+
+  it("resetLibrespotBinaryCache clears a cached positive", async () => {
+    setPlatform("linux");
+    __setLibrespotVersionProbe(async () => {});
+    expect(await checkLibrespotAvailable()).toBe(true);
+    resetLibrespotBinaryCache();
+    __setLibrespotVersionProbe(async () => {
+      throw new Error("gone");
+    });
+    expect(await checkLibrespotAvailable()).toBe(false);
+  });
+
+  it("de-dupes concurrent in-flight probes", async () => {
+    setPlatform("linux");
+    const probe = vi.fn(async () => {});
+    __setLibrespotVersionProbe(probe);
+    const [a, b] = await Promise.all([
+      checkLibrespotAvailable(),
+      checkLibrespotAvailable(),
+    ]);
+    expect(a).toBe(true);
+    expect(b).toBe(true);
+    expect(probe).toHaveBeenCalledTimes(1);
+  });
+});
+
+describe("resolveExecutable", () => {
+  it("returns a bin/-style path (contains a separator) that exists, unchanged", () => {
+    const dir = mkTmpDir("tsmb-resolve-");
+    const full = join(dir, "some-binary");
+    writeFileSync(full, "#!/bin/sh\n");
+    // The path contains a separator so it is checked directly, not via PATH.
+    expect(resolveExecutable(full)).toBe(full);
+  });
+
+  it("returns null for a bin/-style path that does not exist", () => {
+    const full = join(tmpdir(), "tsmb-resolve-missing", "nope-binary");
+    expect(resolveExecutable(full)).toBeNull();
+  });
+
+  it("resolves a BARE command name found in a PATH directory (the I3 fix)", () => {
+    // This is the regression the fix targets: a PATH-installed binary (bare
+    // name, no separator) must resolve against $PATH, not process.cwd().
+    const dir = mkTmpDir("tsmb-resolve-path-");
+    const exeName = process.platform === "win32" ? "faketool.exe" : "faketool";
+    const full = join(dir, exeName);
+    writeFileSync(full, "#!/bin/sh\n");
+    process.env.PATH = dir;
+    expect(resolveExecutable(exeName)).toBe(full);
+  });
+
+  it("returns null for a bare name not present in any PATH directory", () => {
+    process.env.PATH = mkTmpDir("tsmb-resolve-empty-");
+    expect(resolveExecutable("definitely-not-a-real-binary-xyz")).toBeNull();
+  });
+
+  it("appends PATHEXT extensions on win32 to resolve a bare (extensionless) name", () => {
+    setPlatform("win32");
+    const dir = mkTmpDir("tsmb-resolve-pathext-");
+    const full = join(dir, "mytool.CMD");
+    writeFileSync(full, "@echo hi\n");
+    process.env.PATH = dir;
+    process.env.PATHEXT = ".EXE;.CMD;.BAT;.COM";
+    // Bare "mytool" has no extension; win32 resolution must try PATHEXT and
+    // find mytool.CMD.
+    expect(resolveExecutable("mytool")).toBe(full);
+  });
+
+  it("does not touch PATH for a bin/-style relative path with a separator", () => {
+    // A candidate with a separator is checked directly even if PATH is empty.
+    process.env.PATH = "";
+    const dir = mkTmpDir("tsmb-resolve-direct-");
+    const full = join(dir, "direct-binary");
+    writeFileSync(full, "#!/bin/sh\n");
+    expect(resolveExecutable(full)).toBe(full);
+  });
+});
+
+describe("isLibrespotPresent (PATH-aware, sync)", () => {
+  it("true when the bare librespot name resolves on PATH (posix)", () => {
+    setPlatform("linux");
+    const dir = mkTmpDir("tsmb-librespot-path-");
+    writeFileSync(join(dir, "librespot"), "#!/bin/sh\n");
+    process.env.PATH = dir;
+    expect(isLibrespotPresent()).toBe(true);
+  });
+
+  it("true when librespot.exe resolves on PATH (win32)", () => {
+    setPlatform("win32");
+    const dir = mkTmpDir("tsmb-librespot-win-");
+    writeFileSync(join(dir, "librespot.exe"), "MZ\n");
+    process.env.PATH = dir;
+    process.env.PATHEXT = ".EXE;.CMD;.BAT;.COM";
+    expect(isLibrespotPresent()).toBe(true);
+  });
+
+  it("false when librespot is not on PATH", () => {
+    setPlatform("linux");
+    process.env.PATH = mkTmpDir("tsmb-librespot-empty-");
+    expect(isLibrespotPresent()).toBe(false);
+  });
+});
+
+describe("isGoLibrespotPresent (PATH-aware, sync)", () => {
+  it("true when go-librespot resolves on PATH (linux)", () => {
+    setPlatform("linux");
+    const dir = mkTmpDir("tsmb-go-path-");
+    writeFileSync(join(dir, "go-librespot"), "#!/bin/sh\n");
+    process.env.PATH = dir;
+    expect(isGoLibrespotPresent()).toBe(true);
+  });
+
+  it("false on non-linux platforms regardless of PATH (unsupported gate)", () => {
+    setPlatform("win32");
+    const dir = mkTmpDir("tsmb-go-win-");
+    writeFileSync(join(dir, "go-librespot"), "#!/bin/sh\n");
+    process.env.PATH = dir;
+    expect(isGoLibrespotPresent()).toBe(false);
+  });
+
+  it("false on linux when go-librespot is not on PATH", () => {
+    setPlatform("linux");
+    process.env.PATH = mkTmpDir("tsmb-go-empty-");
+    expect(isGoLibrespotPresent()).toBe(false);
+  });
+});

src/music/spotify/binary.ts

@@ -0,0 +1,244 @@
+import { execFile } from "node:child_process";
+import { promisify } from "node:util";
+import { existsSync } from "node:fs";
+import { fileURLToPath } from "node:url";
+import { dirname, join, delimiter } from "node:path";
+
+const execFileAsync = promisify(execFile);
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+
+/**
+ * Resolve a command to an existing absolute path, SYNCHRONOUSLY. A candidate
+ * that already contains a path separator (a project bin/ path) is checked
+ * directly; a BARE command name (e.g. "librespot" / "go-librespot") is searched
+ * across the $PATH directories — with PATHEXT extensions appended on win32 — so
+ * a scoop/choco/cargo/apt PATH install resolves. Returns the resolved path, or
+ * null when nothing exists.
+ *
+ * This is the sync counterpart to checkLibrespotAvailable()/…GoLibrespot… and
+ * is what the hot-path presence gates (chooseBackend/isAvailable) rely on: a
+ * bare name must NOT be handed to existsSync() directly, since existsSync
+ * resolves it against process.cwd() rather than PATH (Bug I3/m1).
+ */
+export function resolveExecutable(cmd: string): string | null {
+  if (cmd.includes("/") || cmd.includes("\\")) {
+    return existsSync(cmd) ? cmd : null;
+  }
+  const dirs = (process.env.PATH || "").split(delimiter).filter(Boolean);
+  const exts =
+    process.platform === "win32"
+      ? (process.env.PATHEXT || ".EXE;.CMD;.BAT;.COM").split(";").filter(Boolean)
+      : [""];
+  for (const dir of dirs) {
+    for (const ext of exts) {
+      const hasExt = ext && cmd.toLowerCase().endsWith(ext.toLowerCase());
+      const full = join(dir, hasExt ? cmd : cmd + ext);
+      if (existsSync(full)) return full;
+    }
+  }
+  return null;
+}
+
+/**
+ * True only on Linux. go-librespot ships Linux-only release binaries and the
+ * sidecar relies on a POSIX FIFO (mkfifo), so the Spotify audio backend is
+ * gated to Linux/Docker. Everywhere else the caller falls back to the Stage-1
+ * sentinel-skip message.
+ */
+export function isGoLibrespotSupported(): boolean {
+  return process.platform === "linux";
+}
+
+/**
+ * Pure resolver core behind findGoLibrespot(). Returns the first candidate
+ * that is either a bare command name (left for execFile to resolve via PATH)
+ * or an existing bin/ file. Exported so tests can inject candidates + a fake
+ * existence predicate and need no real binary on disk.
+ */
+export function pickGoLibrespotPath(
+  candidates: string[],
+  exists: (p: string) => boolean,
+): string {
+  for (const c of candidates) {
+    // bin/ paths only count when the file is actually present; bare names are
+    // returned unconditionally and resolved later via PATH.
+    const isBinPath = c.includes(join("bin", "go-librespot"));
+    if (!isBinPath || exists(c)) return c;
+  }
+  return "go-librespot";
+}
+
+/** Resolve the go-librespot binary path: project bin/ dir first, then PATH. */
+export function findGoLibrespot(): string {
+  // src/music/spotify -> ../../../bin (one level deeper than youtube.ts).
+  const binPath = join(__dirname, "..", "..", "..", "bin", "go-librespot");
+  return pickGoLibrespotPath([binPath, "go-librespot"], existsSync);
+}
+
+/**
+ * SYNCHRONOUS presence gate for go-librespot: supported platform (linux) AND
+ * the resolved binary (project bin/ OR a PATH install) actually exists. This is
+ * what chooseBackend()/isAvailable() must use — NOT existsSync(findGoLibrespot())
+ * which cannot see a bare PATH name (Bug I3/m1).
+ */
+export function isGoLibrespotPresent(): boolean {
+  return isGoLibrespotSupported() && resolveExecutable(findGoLibrespot()) !== null;
+}
+
+// Injectable `--version` probe. Defaults to the real execFile call; tests
+// override it so checkGoLibrespotAvailable() needs no real binary. Keeps the
+// public checkGoLibrespotAvailable() signature param-free per the contract.
+type VersionProbe = (bin: string) => Promise<void>;
+const realProbe: VersionProbe = async (bin) => {
+  await execFileAsync(bin, ["--version"], { timeout: 5_000, maxBuffer: 1024 });
+};
+let versionProbe: VersionProbe = realProbe;
+
+/** Test hook: override the `--version` probe, or restore the default with null. */
+export function __setGoLibrespotVersionProbe(
+  probe: VersionProbe | null,
+): void {
+  versionProbe = probe ?? realProbe;
+}
+
+/**
+ * Availability check for go-librespot. Returns false immediately on non-Linux
+ * platforms (unsupported). Otherwise runs `go-librespot --version` (5s timeout)
+ * and caches ONLY the positive result — a missing binary is retried on the
+ * next call so the operator can install it without restarting the server.
+ */
+let cachedAvailable = false;
+let pendingCheck: Promise<boolean> | null = null;
+export async function checkGoLibrespotAvailable(): Promise<boolean> {
+  if (!isGoLibrespotSupported()) return false;
+  if (cachedAvailable) return true;
+  if (pendingCheck) return pendingCheck;
+  pendingCheck = (async () => {
+    try {
+      await versionProbe(findGoLibrespot());
+      cachedAvailable = true;
+      return true;
+    } catch {
+      return false;
+    } finally {
+      pendingCheck = null;
+    }
+  })();
+  return pendingCheck;
+}
+
+/** Force re-detection on the next call (for tests). */
+export function resetGoLibrespotBinaryCache(): void {
+  cachedAvailable = false;
+  pendingCheck = null;
+}
+
+// ---------------------------------------------------------------------------
+// Rust librespot (librespot-org) resolver — mirrors the go-librespot fns
+// above. Unlike go-librespot, Rust librespot's `--backend pipe` writes PCM to
+// *stdout* on every platform (no FIFO, no audio device), so it is supported
+// on Windows/macOS/Linux alike and the binary is named librespot.exe on win32.
+// ---------------------------------------------------------------------------
+
+/**
+ * True on ALL platforms. The Rust librespot pipe backend writes raw bytes to
+ * process stdout, which Node's spawned child.stdout receives unmodified on
+ * Windows too — so there is no platform gate here (contrast
+ * isGoLibrespotSupported, which is Linux-only).
+ */
+export function isRustLibrespotSupported(): boolean {
+  return true;
+}
+
+/**
+ * Pure resolver core behind findLibrespot(). Returns the first candidate that
+ * is either a bare command name (left for execFile to resolve via PATH) or an
+ * existing bin/ file. Exported so tests can inject candidates + a fake
+ * existence predicate and need no real binary on disk. Mirrors
+ * pickGoLibrespotPath but keys off the win32 exe name.
+ */
+export function pickLibrespotPath(
+  candidates: string[],
+  exists: (p: string) => boolean,
+): string {
+  const exe = process.platform === "win32" ? "librespot.exe" : "librespot";
+  for (const c of candidates) {
+    // bin/ paths only count when the file is actually present; bare names are
+    // returned unconditionally and resolved later via PATH.
+    const isBinPath = c.includes(join("bin", "librespot"));
+    if (!isBinPath || exists(c)) return c;
+  }
+  return exe;
+}
+
+/**
+ * Resolve the Rust librespot binary path: project bin/ dir first, then PATH.
+ * On win32 both the bin/librespot.exe candidate and the bare "librespot.exe"
+ * fallback are used so a PATH-installed librespot.exe (scoop/choco) resolves.
+ */
+export function findLibrespot(): string {
+  const exe = process.platform === "win32" ? "librespot.exe" : "librespot";
+  // src/music/spotify -> ../../../bin (same depth as findGoLibrespot).
+  const binExe = join(__dirname, "..", "..", "..", "bin", exe);
+  const binBare = join(__dirname, "..", "..", "..", "bin", "librespot");
+  return pickLibrespotPath([binExe, binBare, exe], existsSync);
+}
+
+/**
+ * SYNCHRONOUS presence gate for Rust librespot: supported everywhere AND the
+ * resolved binary (project bin/ OR a scoop/choco/cargo PATH install) actually
+ * exists. This is what chooseBackend()/isAvailable() must use — NOT
+ * existsSync(findLibrespot()) which cannot see a bare PATH name (Bug I3/m1).
+ */
+export function isLibrespotPresent(): boolean {
+  return isRustLibrespotSupported() && resolveExecutable(findLibrespot()) !== null;
+}
+
+// Injectable `--version` probe. Defaults to the real execFile call; tests
+// override it so checkLibrespotAvailable() needs no real binary. Keeps the
+// public checkLibrespotAvailable() signature param-free per the contract.
+type LibrespotVersionProbe = (bin: string) => Promise<void>;
+const realLibrespotProbe: LibrespotVersionProbe = async (bin) => {
+  await execFileAsync(bin, ["--version"], { timeout: 5_000, maxBuffer: 1024 });
+};
+let librespotVersionProbe: LibrespotVersionProbe = realLibrespotProbe;
+
+/** Test hook: override the `--version` probe, or restore the default with null. */
+export function __setLibrespotVersionProbe(
+  probe: LibrespotVersionProbe | null,
+): void {
+  librespotVersionProbe = probe ?? realLibrespotProbe;
+}
+
+/**
+ * Availability check for Rust librespot. No platform gate (supported
+ * everywhere). Runs `librespot --version` (5s timeout) and caches ONLY the
+ * positive result — a missing binary is retried on the next call so the
+ * operator can install it (cargo/scoop/choco) without restarting the server.
+ */
+let rustCachedAvailable = false;
+let rustPendingCheck: Promise<boolean> | null = null;
+export async function checkLibrespotAvailable(): Promise<boolean> {
+  if (!isRustLibrespotSupported()) return false;
+  if (rustCachedAvailable) return true;
+  if (rustPendingCheck) return rustPendingCheck;
+  rustPendingCheck = (async () => {
+    try {
+      await librespotVersionProbe(findLibrespot());
+      rustCachedAvailable = true;
+      return true;
+    } catch {
+      return false;
+    } finally {
+      rustPendingCheck = null;
+    }
+  })();
+  return rustPendingCheck;
+}
+
+/** Force re-detection on the next call (for tests). */
+export function resetLibrespotBinaryCache(): void {
+  rustCachedAvailable = false;
+  rustPendingCheck = null;
+}

src/music/spotify/connect-api.test.ts

@@ -0,0 +1,396 @@
+import { describe, it, expect, vi } from "vitest";
+import type { AxiosInstance } from "axios";
+import { SpotifyConnectApi } from "./connect-api.js";
+
+/** Minimal axios stub: only get/put are exercised by the Connect client. */
+function makeHttp(overrides?: Partial<Record<"get" | "put", any>>) {
+  return {
+    get: vi.fn().mockResolvedValue({ status: 200, data: {} }),
+    put: vi.fn().mockResolvedValue({ status: 200, data: {} }),
+    ...overrides,
+  } as unknown as AxiosInstance;
+}
+
+const AUTH = { headers: { Authorization: "Bearer tok123" } };
+const token = () =>
+  vi.fn<() => Promise<string | null>>().mockResolvedValue("tok123");
+
+describe("SpotifyConnectApi.getDevices", () => {
+  it("GETs /v1/me/player/devices with the bearer header and maps the list", async () => {
+    const http = makeHttp({
+      get: vi.fn().mockResolvedValue({
+        status: 200,
+        data: {
+          devices: [
+            { id: "dev-1", name: "TS Bot", is_active: true, type: "Speaker" },
+            { id: "dev-2", name: "Phone", is_active: false },
+          ],
+        },
+      }),
+    });
+    const api = new SpotifyConnectApi(token(), { http });
+    const devices = await api.getDevices();
+    expect(http.get).toHaveBeenCalledWith("/v1/me/player/devices", AUTH);
+    expect(devices).toEqual([
+      { id: "dev-1", name: "TS Bot", is_active: true },
+      { id: "dev-2", name: "Phone", is_active: false },
+    ]);
+  });
+
+  it("returns [] when getToken() is null (unauthorized) without calling http", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(vi.fn().mockResolvedValue(null), { http });
+    await expect(api.getDevices()).resolves.toEqual([]);
+    expect(http.get).not.toHaveBeenCalled();
+  });
+
+  it("returns [] on a 401/network rejection (graceful)", async () => {
+    const err: any = new Error("unauthorized");
+    err.response = { status: 401 };
+    const http = makeHttp({ get: vi.fn().mockRejectedValue(err) });
+    const api = new SpotifyConnectApi(token(), { http });
+    await expect(api.getDevices()).resolves.toEqual([]);
+  });
+});
+
+describe("SpotifyConnectApi.findDeviceByName", () => {
+  it("returns the matching device id", async () => {
+    const http = makeHttp({
+      get: vi.fn().mockResolvedValue({
+        status: 200,
+        data: { devices: [{ id: "dev-1", name: "TS Bot", is_active: false }] },
+      }),
+    });
+    const api = new SpotifyConnectApi(token(), { http });
+    await expect(api.findDeviceByName("TS Bot")).resolves.toBe("dev-1");
+  });
+
+  it("returns null when no device name matches", async () => {
+    const http = makeHttp({
+      get: vi.fn().mockResolvedValue({
+        status: 200,
+        data: { devices: [{ id: "dev-1", name: "Other", is_active: false }] },
+      }),
+    });
+    const api = new SpotifyConnectApi(token(), { http });
+    await expect(api.findDeviceByName("TS Bot")).resolves.toBeNull();
+  });
+});
+
+describe("SpotifyConnectApi mutating calls", () => {
+  it("transfer() PUTs /v1/me/player with device_ids + play=false default", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(token(), { http });
+    await api.transfer("dev-1");
+    expect(http.put).toHaveBeenCalledWith(
+      "/v1/me/player",
+      { device_ids: ["dev-1"], play: false },
+      AUTH,
+    );
+  });
+
+  it("transfer(id, true) forwards play=true", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(token(), { http });
+    await api.transfer("dev-1", true);
+    expect(http.put).toHaveBeenCalledWith(
+      "/v1/me/player",
+      { device_ids: ["dev-1"], play: true },
+      AUTH,
+    );
+  });
+
+  it("play() PUTs /v1/me/player/play?device_id= with the uris body", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(token(), { http });
+    await api.play("dev-1", "spotify:track:abc");
+    expect(http.put).toHaveBeenCalledWith(
+      "/v1/me/player/play",
+      { uris: ["spotify:track:abc"] },
+      { headers: { Authorization: "Bearer tok123" }, params: { device_id: "dev-1" } },
+    );
+  });
+
+  it("pause() PUTs /v1/me/player/pause (no params) with no body", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(token(), { http });
+    await api.pause();
+    expect(http.put).toHaveBeenCalledWith("/v1/me/player/pause", undefined, {
+      headers: { Authorization: "Bearer tok123" },
+      params: undefined,
+    });
+  });
+
+  it("pause(id) forwards device_id param", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(token(), { http });
+    await api.pause("dev-1");
+    expect(http.put).toHaveBeenCalledWith("/v1/me/player/pause", undefined, {
+      headers: { Authorization: "Bearer tok123" },
+      params: { device_id: "dev-1" },
+    });
+  });
+
+  it("resume() PUTs /v1/me/player/play with no uris body (resume)", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(token(), { http });
+    await api.resume();
+    expect(http.put).toHaveBeenCalledWith("/v1/me/player/play", undefined, {
+      headers: { Authorization: "Bearer tok123" },
+      params: undefined,
+    });
+  });
+
+  it("resume(id) forwards device_id param", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(token(), { http });
+    await api.resume("dev-1");
+    expect(http.put).toHaveBeenCalledWith("/v1/me/player/play", undefined, {
+      headers: { Authorization: "Bearer tok123" },
+      params: { device_id: "dev-1" },
+    });
+  });
+
+  it("seek() PUTs /v1/me/player/seek?position_ms=", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(token(), { http });
+    await api.seek(42000);
+    expect(http.put).toHaveBeenCalledWith("/v1/me/player/seek", undefined, {
+      headers: { Authorization: "Bearer tok123" },
+      params: { position_ms: 42000 },
+    });
+  });
+
+  it("seek(ms, id) adds device_id param", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(token(), { http });
+    await api.seek(1000, "dev-1");
+    expect(http.put).toHaveBeenCalledWith("/v1/me/player/seek", undefined, {
+      headers: { Authorization: "Bearer tok123" },
+      params: { position_ms: 1000, device_id: "dev-1" },
+    });
+  });
+
+  it("mutating calls no-op (no http.put) when unauthorized", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(vi.fn().mockResolvedValue(null), { http });
+    await api.transfer("dev-1");
+    await api.play("dev-1", "spotify:track:x");
+    await api.pause();
+    expect(http.put).not.toHaveBeenCalled();
+  });
+});
+
+/**
+ * REQUIRED CORRECTION C3.6: mutating calls must NOT reject up the queue-advance
+ * path. A transient 403 (non-Premium) / 404 (no active device) / 429
+ * (rate-limited) from Spotify must be swallowed (resolve to void), never thrown,
+ * so a failed play() degrades to "couldn't play" instead of an unhandled
+ * rejection that crashes the backend.
+ */
+describe("SpotifyConnectApi C3.6 — mutating calls are resilient (no throw)", () => {
+  // S4.6: transient statuses (404/429) now retry with backoff; inject a no-op
+  // sleep so these swallow-guarantee tests stay instant (no real timers). The
+  // no-throw/swallow contract asserted here is unchanged.
+  const noSleep = async () => {};
+
+  function rejectingHttp(status: number) {
+    const err: any = new Error(`http ${status}`);
+    err.response = { status };
+    return makeHttp({ put: vi.fn().mockRejectedValue(err) });
+  }
+
+  it("play() does NOT throw on a 404 (no active device)", async () => {
+    const api = new SpotifyConnectApi(token(), {
+      http: rejectingHttp(404),
+      sleep: noSleep,
+    });
+    await expect(api.play("dev-1", "spotify:track:abc")).resolves.toBeUndefined();
+  });
+
+  it("play() does NOT throw on a 429 (rate-limited)", async () => {
+    const api = new SpotifyConnectApi(token(), {
+      http: rejectingHttp(429),
+      sleep: noSleep,
+    });
+    await expect(api.play("dev-1", "spotify:track:abc")).resolves.toBeUndefined();
+  });
+
+  it("transfer() does NOT throw on a 403 (non-Premium)", async () => {
+    const api = new SpotifyConnectApi(token(), { http: rejectingHttp(403) });
+    await expect(api.transfer("dev-1", true)).resolves.toBeUndefined();
+  });
+
+  it("pause/resume/seek do NOT throw on a rejection", async () => {
+    const api = new SpotifyConnectApi(token(), {
+      http: rejectingHttp(404),
+      sleep: noSleep,
+    });
+    await expect(api.pause("dev-1")).resolves.toBeUndefined();
+    await expect(api.resume("dev-1")).resolves.toBeUndefined();
+    await expect(api.seek(1000, "dev-1")).resolves.toBeUndefined();
+  });
+
+  it("play() does NOT throw on a raw network error (no response)", async () => {
+    const http = makeHttp({ put: vi.fn().mockRejectedValue(new Error("ECONNRESET")) });
+    const api = new SpotifyConnectApi(token(), { http });
+    await expect(api.play("dev-1", "spotify:track:abc")).resolves.toBeUndefined();
+  });
+});
+
+/**
+ * Task S4.6: bounded retry/backoff on the mutating Connect commands
+ * (spec §4.3/§13 recovery/watchdog). Transient statuses {404,429,500,502,503}
+ * retry up to MAX_ATTEMPTS (3) with exponential backoff; non-transient statuses
+ * are NOT retried. Every path still preserves C3.6 (swallow, never throw). A
+ * no-op injected `sleep` keeps the tests instant (no real timers).
+ */
+describe("SpotifyConnectApi S4.6 — retry/backoff on mutating commands", () => {
+  const MAX_ATTEMPTS = 3;
+  const noSleep = async () => {};
+
+  function rejectStatus(status: number, headers?: Record<string, string>) {
+    const err: any = new Error(`http ${status}`);
+    err.response = { status, headers };
+    return err;
+  }
+
+  it("play() retries a transient 404 then succeeds (2 calls, no throw)", async () => {
+    const put = vi
+      .fn()
+      .mockRejectedValueOnce(rejectStatus(404))
+      .mockResolvedValueOnce({ status: 200, data: {} });
+    const http = makeHttp({ put });
+    const api = new SpotifyConnectApi(token(), { http, sleep: noSleep });
+    await expect(api.play("dev-1", "spotify:track:abc")).resolves.toBeUndefined();
+    expect(put).toHaveBeenCalledTimes(2);
+  });
+
+  it("play() exhausts on a persistent 500 (MAX_ATTEMPTS calls, swallowed, warns once)", async () => {
+    const put = vi.fn().mockRejectedValue(rejectStatus(500));
+    const http = makeHttp({ put });
+    const warn = vi.fn();
+    const logger = { warn } as any;
+    const api = new SpotifyConnectApi(token(), { http, sleep: noSleep, logger });
+    await expect(api.play("dev-1", "spotify:track:abc")).resolves.toBeUndefined();
+    expect(put).toHaveBeenCalledTimes(MAX_ATTEMPTS);
+    expect(warn).toHaveBeenCalledTimes(1);
+  });
+
+  it("does NOT retry a non-transient 403 (exactly ONE call, no throw)", async () => {
+    const put = vi.fn().mockRejectedValue(rejectStatus(403));
+    const http = makeHttp({ put });
+    const api = new SpotifyConnectApi(token(), { http, sleep: noSleep });
+    await expect(api.play("dev-1", "spotify:track:abc")).resolves.toBeUndefined();
+    expect(put).toHaveBeenCalledTimes(1);
+  });
+
+  it("429 honors a CAPPED Retry-After then succeeds (2 calls, bounded sleep)", async () => {
+    const put = vi
+      .fn()
+      .mockRejectedValueOnce(rejectStatus(429, { "retry-after": "1" }))
+      .mockResolvedValueOnce({ status: 200, data: {} });
+    const http = makeHttp({ put });
+    const sleep = vi.fn<(ms: number) => Promise<void>>(async () => {});
+    const api = new SpotifyConnectApi(token(), { http, sleep });
+    await expect(api.play("dev-1", "spotify:track:abc")).resolves.toBeUndefined();
+    expect(put).toHaveBeenCalledTimes(2);
+    expect(sleep).toHaveBeenCalledTimes(1);
+    const delay = sleep.mock.calls[0][0];
+    expect(delay).toBe(1000);
+    expect(delay).toBeLessThanOrEqual(2000);
+  });
+
+  it("transfer() shares the retry path — 404 then success (2 calls)", async () => {
+    const put = vi
+      .fn()
+      .mockRejectedValueOnce(rejectStatus(404))
+      .mockResolvedValueOnce({ status: 200, data: {} });
+    const http = makeHttp({ put });
+    const api = new SpotifyConnectApi(token(), { http, sleep: noSleep });
+    await expect(api.transfer("dev-1", true)).resolves.toBeUndefined();
+    expect(put).toHaveBeenCalledTimes(2);
+  });
+});
+
+describe("SpotifyConnectApi.getPlaybackState", () => {
+  it("GETs /v1/me/player and maps is_playing/progress/item", async () => {
+    const http = makeHttp({
+      get: vi.fn().mockResolvedValue({
+        status: 200,
+        data: {
+          is_playing: true,
+          progress_ms: 12345,
+          item: { uri: "spotify:track:abc", duration_ms: 200000 },
+        },
+      }),
+    });
+    const api = new SpotifyConnectApi(token(), { http });
+    const state = await api.getPlaybackState();
+    expect(http.get).toHaveBeenCalledWith("/v1/me/player", AUTH);
+    expect(state).toEqual({
+      isPlaying: true,
+      progressMs: 12345,
+      trackUri: "spotify:track:abc",
+      durationMs: 200000,
+    });
+  });
+
+  // R4-4 (multi-bot): the account-wide /v1/me/player response names the single
+  // ACTIVE Connect device. Expose it as activeDeviceId so the Rust backend can
+  // tell "our device" from a foreign device another bot stole the session with.
+  it("maps device.id -> activeDeviceId", async () => {
+    const http = makeHttp({
+      get: vi.fn().mockResolvedValue({
+        status: 200,
+        data: {
+          is_playing: true,
+          progress_ms: 1000,
+          item: { uri: "spotify:track:abc", duration_ms: 200000 },
+          device: { id: "dev-1", name: "TS Bot", is_active: true },
+        },
+      }),
+    });
+    const api = new SpotifyConnectApi(token(), { http });
+    const state = await api.getPlaybackState();
+    expect(state).toEqual({
+      isPlaying: true,
+      progressMs: 1000,
+      trackUri: "spotify:track:abc",
+      durationMs: 200000,
+      activeDeviceId: "dev-1",
+    });
+  });
+
+  it("returns null on 204 (no active device)", async () => {
+    const http = makeHttp({ get: vi.fn().mockResolvedValue({ status: 204, data: "" }) });
+    const api = new SpotifyConnectApi(token(), { http });
+    await expect(api.getPlaybackState()).resolves.toBeNull();
+  });
+
+  it("returns null when item is missing / trackUri null", async () => {
+    const http = makeHttp({
+      get: vi.fn().mockResolvedValue({ status: 200, data: { is_playing: false, progress_ms: 0, item: null } }),
+    });
+    const api = new SpotifyConnectApi(token(), { http });
+    await expect(api.getPlaybackState()).resolves.toEqual({
+      isPlaying: false,
+      progressMs: 0,
+      trackUri: null,
+      durationMs: 0,
+    });
+  });
+
+  it("returns null on rejection (e.g. 401) instead of throwing", async () => {
+    const http = makeHttp({ get: vi.fn().mockRejectedValue(new Error("boom")) });
+    const api = new SpotifyConnectApi(token(), { http });
+    await expect(api.getPlaybackState()).resolves.toBeNull();
+  });
+
+  it("returns null when getToken() is null (unauthorized) without calling http", async () => {
+    const http = makeHttp();
+    const api = new SpotifyConnectApi(vi.fn().mockResolvedValue(null), { http });
+    await expect(api.getPlaybackState()).resolves.toBeNull();
+    expect(http.get).not.toHaveBeenCalled();
+  });
+});

src/music/spotify/connect-api.ts

@@ -0,0 +1,205 @@
+import axios, { type AxiosInstance } from "axios";
+
+const API_BASE = "https://api.spotify.com";
+
+/**
+ * Task S4.6 (spec §4.3/§13 recovery/watchdog): transient Connect-command
+ * failures that warrant a bounded retry with exponential backoff. 404 is the
+ * device-visibility latency case (device not yet enumerated), 429 is rate-limit,
+ * 5xx are Spotify-side flakiness. Everything else (401/403/network) is NOT
+ * retried — it is swallowed immediately (C3.6).
+ */
+const TRANSIENT = new Set([404, 429, 500, 502, 503]);
+const MAX_ATTEMPTS = 3;
+const BASE_DELAY_MS = 150;
+const MAX_DELAY_MS = 2_000;
+
+export interface SpotifyDevice {
+  id: string;
+  name: string;
+  is_active: boolean;
+}
+
+export interface PlaybackState {
+  isPlaying: boolean;
+  progressMs: number;
+  trackUri: string | null;
+  durationMs: number;
+  /**
+   * R4-4 (multi-bot): the id of the single ACTIVE Connect device the
+   * account-wide GET /v1/me/player is reporting (from `device.id`). Absent when
+   * Spotify omits the device block. The Rust backend uses it to tell "our
+   * device" from a foreign device another bot stole the shared session with, so
+   * it never misattributes that bot's track/stop as ours.
+   */
+  activeDeviceId?: string;
+}
+
+/**
+ * Spotify Web API "Connect" remote-control client. Wraps an axios instance and
+ * attaches a live user Bearer token from getToken() to every request.
+ *
+ * Error policy:
+ * - Read-only calls (getDevices/getPlaybackState) degrade to []/null on error.
+ * - Mutating calls (transfer/play/pause/resume/seek) no-op when unauthorized.
+ * - REQUIRED CORRECTION C3.6: mutating calls ALSO swallow transport errors
+ *   (403 non-Premium / 404 no active device / 429 rate-limited / network) and
+ *   resolve to void instead of rejecting. The contract keeps the Promise<void>
+ *   signatures, so the backend treats a failed play as "couldn't play" and
+ *   falls back — a transient Spotify error can never surface as an unhandled
+ *   rejection that crashes the queue-advance path.
+ */
+export class SpotifyConnectApi {
+  private getToken: () => Promise<string | null>;
+  private http: AxiosInstance;
+  private sleep: (ms: number) => Promise<void>;
+  private logger?: import("pino").Logger;
+
+  constructor(
+    getToken: () => Promise<string | null>,
+    deps?: {
+      http?: AxiosInstance;
+      sleep?: (ms: number) => Promise<void>;
+      logger?: import("pino").Logger;
+    },
+  ) {
+    this.getToken = getToken;
+    this.http = deps?.http ?? axios.create({ baseURL: API_BASE, timeout: 15_000 });
+    this.sleep = deps?.sleep ?? ((ms) => new Promise((r) => setTimeout(r, ms)));
+    this.logger = deps?.logger;
+  }
+
+  /** Bearer auth headers, or null when no valid user token is available. */
+  private async authHeaders(): Promise<{ Authorization: string } | null> {
+    const token = await this.getToken();
+    if (!token) return null;
+    return { Authorization: `Bearer ${token}` };
+  }
+
+  /**
+   * S4.6 recovery/watchdog: run a mutating PUT with bounded retry + exponential
+   * backoff on TRANSIENT statuses only. On exhaustion OR a non-transient error
+   * it SWALLOWS and warns once — preserving C3.6 (a mutating command NEVER
+   * rejects up the queue-advance path). Tokens are never logged.
+   */
+  private async mutateWithRetry(put: () => Promise<unknown>): Promise<void> {
+    for (let attempt = 1; attempt <= MAX_ATTEMPTS; attempt++) {
+      try {
+        await put();
+        return;
+      } catch (err: any) {
+        const status = err?.response?.status;
+        if (!TRANSIENT.has(status) || attempt === MAX_ATTEMPTS) {
+          // C3.6: never reject up the queue path — swallow, but surface once.
+          this.logger?.warn(
+            { status },
+            "Spotify Connect command failed (exhausted/non-retryable)",
+          );
+          return;
+        }
+        let delay = Math.min(BASE_DELAY_MS * 2 ** (attempt - 1), MAX_DELAY_MS);
+        if (status === 429) {
+          const ra = Number(err?.response?.headers?.["retry-after"]);
+          if (Number.isFinite(ra) && ra > 0) delay = Math.min(ra * 1000, MAX_DELAY_MS);
+        }
+        await this.sleep(delay);
+      }
+    }
+  }
+
+  async getDevices(): Promise<SpotifyDevice[]> {
+    const headers = await this.authHeaders();
+    if (!headers) return [];
+    try {
+      const { data } = await this.http.get("/v1/me/player/devices", { headers });
+      const list = Array.isArray(data?.devices) ? data.devices : [];
+      return list.map((d: any) => ({
+        id: d?.id ?? "",
+        name: d?.name ?? "",
+        is_active: Boolean(d?.is_active),
+      }));
+    } catch {
+      return [];
+    }
+  }
+
+  async findDeviceByName(name: string): Promise<string | null> {
+    const devices = await this.getDevices();
+    const match = devices.find((d) => d.name === name);
+    return match ? match.id : null;
+  }
+
+  async transfer(deviceId: string, play = false): Promise<void> {
+    const headers = await this.authHeaders();
+    if (!headers) return;
+    await this.mutateWithRetry(() =>
+      this.http.put("/v1/me/player", { device_ids: [deviceId], play }, { headers }),
+    );
+  }
+
+  async play(deviceId: string, trackUri: string): Promise<void> {
+    const headers = await this.authHeaders();
+    if (!headers) return;
+    await this.mutateWithRetry(() =>
+      this.http.put(
+        "/v1/me/player/play",
+        { uris: [trackUri] },
+        { headers, params: { device_id: deviceId } },
+      ),
+    );
+  }
+
+  async pause(deviceId?: string): Promise<void> {
+    const headers = await this.authHeaders();
+    if (!headers) return;
+    await this.mutateWithRetry(() =>
+      this.http.put("/v1/me/player/pause", undefined, {
+        headers,
+        params: deviceId ? { device_id: deviceId } : undefined,
+      }),
+    );
+  }
+
+  async resume(deviceId?: string): Promise<void> {
+    const headers = await this.authHeaders();
+    if (!headers) return;
+    await this.mutateWithRetry(() =>
+      this.http.put("/v1/me/player/play", undefined, {
+        headers,
+        params: deviceId ? { device_id: deviceId } : undefined,
+      }),
+    );
+  }
+
+  async seek(ms: number, deviceId?: string): Promise<void> {
+    const headers = await this.authHeaders();
+    if (!headers) return;
+    const params: Record<string, unknown> = { position_ms: ms };
+    if (deviceId) params.device_id = deviceId;
+    await this.mutateWithRetry(() =>
+      this.http.put("/v1/me/player/seek", undefined, { headers, params }),
+    );
+  }
+
+  async getPlaybackState(): Promise<PlaybackState | null> {
+    const headers = await this.authHeaders();
+    if (!headers) return null;
+    try {
+      const res = await this.http.get("/v1/me/player", { headers });
+      // 204 = no active device / playback; body is empty.
+      if (res.status === 204 || !res.data) return null;
+      const d = res.data;
+      return {
+        isPlaying: Boolean(d.is_playing),
+        progressMs: Number(d.progress_ms ?? 0),
+        trackUri: d.item?.uri ?? null,
+        durationMs: Number(d.item?.duration_ms ?? 0),
+        // R4-4: expose the account's single active device so a foreign steal is
+        // distinguishable from our own device. Left undefined when absent.
+        activeDeviceId: d.device?.id ?? undefined,
+      };
+    } catch {
+      return null;
+    }
+  }
+}

src/music/spotify/controller.test.ts

@@ -0,0 +1,709 @@
+import { describe, it, expect, beforeAll, afterAll, beforeEach, vi } from "vitest";
+import { EventEmitter } from "node:events";
+import { Readable } from "node:stream";
+import { writeFileSync, rmSync } from "node:fs";
+import { join } from "node:path";
+import { tmpdir } from "node:os";
+import type { Logger } from "pino";
+import type { SpotifyConfig } from "../../data/config.js";
+import type {
+  SpotifyAudioBackend,
+  SpotifyTrackEndedEvent,
+  SpotifyNowPlaying,
+} from "./backend.js";
+import type { SpotifyOAuth } from "./spotify-oauth.js";
+
+// Controllable, hoisted so the vi.mock factory can close over it.
+// go-* keys keep their Stage-2 names (`supported`/`path`) so existing tests are
+// untouched; rust* keys drive the new librespot selection paths.
+const bin = vi.hoisted(() => ({
+  supported: true,
+  path: "",
+  rustSupported: true,
+  rustPath: "",
+}));
+vi.mock("./binary.js", async () => {
+  // existsSync mirrors the real resolveExecutable(find*()) result for the
+  // bin/-style temp paths this suite uses (existingBin exists, missingBin does
+  // not), keeping the chooseBackend/isAvailable matrix behavior-identical.
+  const { existsSync } = await import("node:fs");
+  return {
+    isGoLibrespotSupported: () => bin.supported,
+    findGoLibrespot: () => bin.path,
+    resetGoLibrespotBinaryCache: () => {},
+    checkGoLibrespotAvailable: async () => bin.supported && !!bin.path,
+    isRustLibrespotSupported: () => bin.rustSupported,
+    findLibrespot: () => bin.rustPath,
+    resetLibrespotBinaryCache: () => {},
+    checkLibrespotAvailable: async () => bin.rustSupported && !!bin.rustPath,
+    // PATH-aware presence gates (Bug I3): supported gate AND the resolved
+    // binary actually exists on disk.
+    isGoLibrespotPresent: () => bin.supported && existsSync(bin.path),
+    isLibrespotPresent: () => bin.rustSupported && existsSync(bin.rustPath),
+  };
+});
+
+// Capture options the DEFAULT factory hands to the real GoLibrespotBackend so
+// we can assert per-bot ports (Fix 3) are threaded through. Every other test
+// injects its own backendFactory, so this mock is inert for them.
+const goLibrespotCtor = vi.hoisted(() => vi.fn());
+vi.mock("./go-librespot.js", async () => {
+  const { EventEmitter } = await import("node:events");
+  return {
+    GoLibrespotBackend: class extends EventEmitter {
+      constructor(opts: any) {
+        super();
+        goLibrespotCtor(opts);
+      }
+      async start(): Promise<void> {}
+      isReady(): boolean {
+        return true;
+      }
+      stop(): void {}
+      async playTrack(): Promise<void> {}
+      async pause(): Promise<void> {}
+      async resume(): Promise<void> {}
+      async seek(): Promise<void> {}
+      getPcmStream(): any {
+        return null;
+      }
+      getPositionMs(): number {
+        return 0;
+      }
+    },
+  };
+});
+
+// Import AFTER vi.mock so the mocked binary module is used.
+const { SpotifyController, perBotDeviceName } = await import("./controller.js");
+
+const existingBin = join(tmpdir(), `tsmb-golibrespot-${process.pid}`);
+const missingBin = join(tmpdir(), `tsmb-golibrespot-missing-${process.pid}`);
+
+beforeAll(() => {
+  writeFileSync(existingBin, "#!/bin/sh\n");
+});
+afterAll(() => {
+  try {
+    rmSync(existingBin);
+  } catch {
+    /* ignore */
+  }
+});
+beforeEach(() => {
+  bin.supported = true;
+  bin.path = existingBin;
+  bin.rustSupported = true;
+  bin.rustPath = missingBin;
+});
+
+class FakeBackend extends EventEmitter implements SpotifyAudioBackend {
+  startCalls = 0;
+  stopCalls = 0;
+  playCalls: string[] = [];
+  pauseCalls = 0;
+  resumeCalls = 0;
+  seekCalls: number[] = [];
+  ready = false;
+  startShouldReject = false;
+  playShouldReject = false;
+  /** When set, start() awaits this before resolving — lets a test interleave
+   *  stop()/error DURING a mid-flight start (Bug I1). */
+  startGate?: Promise<void>;
+  readonly pcm = Readable.from([Buffer.alloc(0)]);
+
+  async start(): Promise<void> {
+    this.startCalls++;
+    if (this.startGate) await this.startGate;
+    if (this.startShouldReject) throw new Error("start boom");
+    this.ready = true;
+  }
+  stop(): void {
+    this.stopCalls++;
+    this.ready = false;
+  }
+  isReady(): boolean {
+    return this.ready;
+  }
+  async playTrack(uri: string): Promise<void> {
+    this.playCalls.push(uri);
+    if (this.playShouldReject) throw new Error("play boom");
+  }
+  async pause(): Promise<void> {
+    this.pauseCalls++;
+  }
+  async resume(): Promise<void> {
+    this.resumeCalls++;
+  }
+  async seek(ms: number): Promise<void> {
+    this.seekCalls.push(ms);
+  }
+  getPcmStream(): Readable {
+    return this.pcm;
+  }
+  getPositionMs(): number {
+    return 0;
+  }
+}
+
+const silentLogger = {
+  info() {},
+  error() {},
+  warn() {},
+  debug() {},
+  trace() {},
+  fatal() {},
+  child() {
+    return silentLogger;
+  },
+} as unknown as Logger;
+
+function cfg(over: Partial<SpotifyConfig> = {}): SpotifyConfig {
+  return {
+    enabled: true,
+    backend: "auto",
+    clientId: "",
+    clientSecret: "",
+    deviceName: "TSMusicBot",
+    bitrate: 320,
+    ...over,
+  };
+}
+
+function makeCtrl(over: {
+  config?: Partial<SpotifyConfig>;
+  backendFactory?: () => SpotifyAudioBackend;
+  oauth?: import("./spotify-oauth.js").SpotifyOAuth;
+} = {}) {
+  const be = new FakeBackend();
+  const ctrl = new SpotifyController({
+    config: cfg(over.config),
+    workDir: "/tmp/work",
+    configDir: "/tmp/cfg",
+    logger: silentLogger,
+    backendFactory: over.backendFactory ?? (() => be),
+    oauth: over.oauth,
+  });
+  return { ctrl, be };
+}
+
+function fakeOAuth(
+  authorized: boolean,
+  hooks: { onIsAuthorized?: () => void } = {},
+): SpotifyOAuth {
+  return {
+    isAuthorized: () => {
+      hooks.onIsAuthorized?.();
+      return authorized;
+    },
+    getAccessToken: async () => (authorized ? "tok" : null),
+    getClientId: () => "cid",
+    getRedirectUri: () => "http://127.0.0.1:5588/login",
+    buildAuthorizeUrl: () => ({ url: "https://accounts.spotify.com/authorize", state: "s" }),
+    handleCallback: async () => true,
+  } as unknown as SpotifyOAuth;
+}
+
+describe("SpotifyController.isAvailable", () => {
+  it("true when enabled + supported + binary present", () => {
+    const { ctrl } = makeCtrl();
+    expect(ctrl.isAvailable()).toBe(true);
+  });
+  it("false when config disabled", () => {
+    const { ctrl } = makeCtrl({ config: { enabled: false } });
+    expect(ctrl.isAvailable()).toBe(false);
+  });
+  it("false when platform unsupported", () => {
+    bin.supported = false;
+    const { ctrl } = makeCtrl();
+    expect(ctrl.isAvailable()).toBe(false);
+  });
+  it("false when binary file is absent", () => {
+    bin.path = missingBin;
+    const { ctrl } = makeCtrl();
+    expect(ctrl.isAvailable()).toBe(false);
+  });
+});
+
+describe("SpotifyController.ensureStarted", () => {
+  it("starts the backend exactly once across repeated calls", async () => {
+    let built = 0;
+    const be = new FakeBackend();
+    const { ctrl } = makeCtrl({
+      backendFactory: () => {
+        built++;
+        return be;
+      },
+    });
+    expect(await ctrl.ensureStarted()).toBe(true);
+    expect(await ctrl.ensureStarted()).toBe(true);
+    expect(built).toBe(1);
+    expect(be.startCalls).toBe(1);
+  });
+
+  it("is idempotent under concurrent calls (single start)", async () => {
+    let built = 0;
+    const be = new FakeBackend();
+    const { ctrl } = makeCtrl({
+      backendFactory: () => {
+        built++;
+        return be;
+      },
+    });
+    const [a, b] = await Promise.all([ctrl.ensureStarted(), ctrl.ensureStarted()]);
+    expect(a).toBe(true);
+    expect(b).toBe(true);
+    expect(built).toBe(1);
+    expect(be.startCalls).toBe(1);
+  });
+
+  it("returns false and does not build a backend when unavailable", async () => {
+    let built = 0;
+    const { ctrl } = makeCtrl({
+      config: { enabled: false },
+      backendFactory: () => {
+        built++;
+        return new FakeBackend();
+      },
+    });
+    expect(await ctrl.ensureStarted()).toBe(false);
+    expect(built).toBe(0);
+  });
+
+  it("returns false when backend.start() throws, and allows a later retry", async () => {
+    const be = new FakeBackend();
+    be.startShouldReject = true;
+    let built = 0;
+    const { ctrl } = makeCtrl({
+      backendFactory: () => {
+        built++;
+        return be;
+      },
+    });
+    expect(await ctrl.ensureStarted()).toBe(false);
+    // start failure clears the cached promise so a subsequent call retries.
+    be.startShouldReject = false;
+    expect(await ctrl.ensureStarted()).toBe(true);
+    expect(built).toBe(2);
+    expect(be.startCalls).toBe(2);
+  });
+});
+
+describe("SpotifyController.playTrack", () => {
+  it("ensures started then delegates the uri, returning true", async () => {
+    const { ctrl, be } = makeCtrl();
+    expect(await ctrl.playTrack("spotify:track:abc")).toBe(true);
+    expect(be.startCalls).toBe(1);
+    expect(be.playCalls).toEqual(["spotify:track:abc"]);
+  });
+  it("returns false when the controller is unavailable", async () => {
+    const { ctrl, be } = makeCtrl({ config: { enabled: false } });
+    expect(await ctrl.playTrack("spotify:track:abc")).toBe(false);
+    expect(be.playCalls).toEqual([]);
+  });
+  it("returns false when backend.playTrack rejects", async () => {
+    const be = new FakeBackend();
+    be.playShouldReject = true;
+    const { ctrl } = makeCtrl({ backendFactory: () => be });
+    expect(await ctrl.playTrack("spotify:track:abc")).toBe(false);
+  });
+});
+
+describe("SpotifyController transport delegation", () => {
+  it("pause/resume/seek forward to the backend after start", async () => {
+    const { ctrl, be } = makeCtrl();
+    await ctrl.ensureStarted();
+    await ctrl.pause();
+    await ctrl.resume();
+    await ctrl.seek(4200);
+    expect(be.pauseCalls).toBe(1);
+    expect(be.resumeCalls).toBe(1);
+    expect(be.seekCalls).toEqual([4200]);
+  });
+  it("pause/resume/seek are safe no-ops before start", async () => {
+    const { ctrl, be } = makeCtrl();
+    await expect(ctrl.pause()).resolves.toBeUndefined();
+    await expect(ctrl.resume()).resolves.toBeUndefined();
+    await expect(ctrl.seek(10)).resolves.toBeUndefined();
+    expect(be.pauseCalls).toBe(0);
+  });
+  it("getPcmStream returns the backend stream", async () => {
+    const { ctrl, be } = makeCtrl();
+    await ctrl.ensureStarted();
+    expect(ctrl.getPcmStream()).toBe(be.pcm);
+  });
+  it("getPcmStream throws before the backend is started", () => {
+    const { ctrl } = makeCtrl();
+    expect(() => ctrl.getPcmStream()).toThrow();
+  });
+});
+
+// R4-1: the web progress bar computes seekTime = ratio * duration (fractional
+// seconds); BotInstance routes Spotify seeks through seek(seconds * 1000),
+// yielding a NON-integer ms (e.g. 71610.00000000001). go-librespot decodes
+// `position` into an int64 and Go's encoding/json REJECTS a JSON number with a
+// decimal point -> HTTP 400 -> the error is swallowed -> the track never seeks.
+// The controller must round ONCE so BOTH backends get a valid integer ms.
+describe("SpotifyController.seek integer rounding (R4-1)", () => {
+  it("rounds a fractional seek to an integer ms before forwarding to the backend", async () => {
+    const { ctrl, be } = makeCtrl();
+    await ctrl.ensureStarted();
+    await ctrl.seek(71610.00000000001);
+    expect(be.seekCalls).toHaveLength(1);
+    expect(Number.isInteger(be.seekCalls[0])).toBe(true);
+    expect(be.seekCalls[0]).toBe(71610);
+  });
+
+  it("clamps a negative seek to 0", async () => {
+    const { ctrl, be } = makeCtrl();
+    await ctrl.ensureStarted();
+    await ctrl.seek(-5);
+    expect(be.seekCalls).toEqual([0]);
+  });
+
+  it("passes an already-integer seek through unchanged", async () => {
+    const { ctrl, be } = makeCtrl();
+    await ctrl.ensureStarted();
+    await ctrl.seek(4200);
+    expect(be.seekCalls).toEqual([4200]);
+  });
+});
+
+describe("SpotifyController event re-emission", () => {
+  it("re-emits backend trackEnded with the same payload", async () => {
+    const { ctrl, be } = makeCtrl();
+    await ctrl.ensureStarted();
+    const got: SpotifyTrackEndedEvent[] = [];
+    ctrl.on("trackEnded", (e) => got.push(e));
+    const evt: SpotifyTrackEndedEvent = { uri: "spotify:track:x", reason: "ended" };
+    be.emit("trackEnded", evt);
+    expect(got).toEqual([evt]);
+  });
+  it("re-emits backend metadata with the same payload", async () => {
+    const { ctrl, be } = makeCtrl();
+    await ctrl.ensureStarted();
+    const got: SpotifyNowPlaying[] = [];
+    ctrl.on("metadata", (m) => got.push(m));
+    const meta: SpotifyNowPlaying = {
+      uri: "spotify:track:x",
+      name: "Song",
+      artist: "Artist",
+      album: "Album",
+      coverUrl: "http://img",
+      durationMs: 1000,
+    };
+    be.emit("metadata", meta);
+    expect(got).toEqual([meta]);
+  });
+});
+
+describe("SpotifyController backend error handling (C3)", () => {
+  it("does NOT throw on a backend 'error' with no controller listener, and marks not-ready", async () => {
+    const be1 = new FakeBackend();
+    const be2 = new FakeBackend();
+    const backends = [be1, be2];
+    let built = 0;
+    const { ctrl } = makeCtrl({
+      backendFactory: () => {
+        built++;
+        return backends.shift()!;
+      },
+    });
+    await ctrl.ensureStarted();
+    expect(built).toBe(1);
+    // The controller itself has NO "error" listener. A raw re-emit would make
+    // Node throw here; the controller must swallow+log instead.
+    expect(() => be1.emit("error", new Error("sidecar boom"))).not.toThrow();
+    // Marked not-ready: a fresh ensureStarted relaunches a new backend.
+    expect(await ctrl.ensureStarted()).toBe(true);
+    expect(built).toBe(2);
+    expect(be2.startCalls).toBe(1);
+  });
+
+  it("tears down the errored backend (stop + detach + null) so it is not orphaned", async () => {
+    const be1 = new FakeBackend();
+    const be2 = new FakeBackend();
+    const backends = [be1, be2];
+    let built = 0;
+    const { ctrl } = makeCtrl({
+      backendFactory: () => {
+        built++;
+        return backends.shift()!;
+      },
+    });
+    await ctrl.ensureStarted();
+    expect(built).toBe(1);
+
+    // On "error" the controller must stop() the errored backend (cleans its
+    // ffmpeg/go-librespot children + FIFO) and detach ALL its listeners.
+    expect(() => be1.emit("error", new Error("sidecar boom"))).not.toThrow();
+    expect(be1.stopCalls).toBe(1);
+    expect(be1.listenerCount("error")).toBe(0);
+    expect(be1.listenerCount("trackEnded")).toBe(0);
+    expect(be1.listenerCount("metadata")).toBe(0);
+
+    // Internal backend is null: a transport call no-ops (delegates to nothing)
+    // and getPcmStream throws until a rebuild.
+    await ctrl.pause();
+    expect(be1.pauseCalls).toBe(0);
+    expect(() => ctrl.getPcmStream()).toThrow();
+
+    // A fresh ensureStarted builds a NEW backend instance.
+    expect(await ctrl.ensureStarted()).toBe(true);
+    expect(built).toBe(2);
+    expect(be2.startCalls).toBe(1);
+    expect(ctrl.getPcmStream()).toBe(be2.pcm);
+  });
+
+  it("does not cross-talk: a later error from the ORPHANED backend leaves the healthy rebuilt controller ready", async () => {
+    const be1 = new FakeBackend();
+    const be2 = new FakeBackend();
+    const backends = [be1, be2];
+    let built = 0;
+    const { ctrl } = makeCtrl({
+      backendFactory: () => {
+        built++;
+        return backends.shift()!;
+      },
+    });
+    await ctrl.ensureStarted();
+
+    // First error tears down be1 and the controller rebuilds onto healthy be2.
+    be1.emit("error", new Error("sidecar boom"));
+    expect(await ctrl.ensureStarted()).toBe(true);
+    expect(built).toBe(2);
+    await ctrl.pause();
+    expect(be2.pauseCalls).toBe(1);
+
+    // A SECOND error emitted by the OLD (orphaned) backend must NOT reach the
+    // controller: the healthy be2 stays owned, ready, and untouched.
+    be1.on("error", () => {}); // controller detached; re-arm to avoid unhandled throw
+    expect(() => be1.emit("error", new Error("orphan boom"))).not.toThrow();
+    expect(be2.stopCalls).toBe(0); // healthy backend not torn down
+    // Still ready: ensureStarted returns true without rebuilding a third time.
+    expect(await ctrl.ensureStarted()).toBe(true);
+    expect(built).toBe(2);
+    await ctrl.pause();
+    expect(be2.pauseCalls).toBe(2);
+    expect(ctrl.getPcmStream()).toBe(be2.pcm);
+  });
+});
+
+describe("SpotifyController.stop", () => {
+  it("stops the backend and tears down state so a later start rebuilds", async () => {
+    const be1 = new FakeBackend();
+    const be2 = new FakeBackend();
+    const backends = [be1, be2];
+    const { ctrl } = makeCtrl({ backendFactory: () => backends.shift()! });
+    await ctrl.ensureStarted();
+    ctrl.stop();
+    expect(be1.stopCalls).toBe(1);
+    // After teardown getPcmStream is invalid again until re-started.
+    expect(() => ctrl.getPcmStream()).toThrow();
+    // A fresh ensureStarted builds a new backend.
+    expect(await ctrl.ensureStarted()).toBe(true);
+    expect(be2.startCalls).toBe(1);
+  });
+  it("stop before start is a safe no-op", () => {
+    const { ctrl, be } = makeCtrl();
+    expect(() => ctrl.stop()).not.toThrow();
+    expect(be.stopCalls).toBe(0);
+  });
+
+  it("Bug I1: stop() DURING a mid-flight start tears the sidecar down instead of resurrecting it", async () => {
+    // A Deferred the test resolves to complete backend.start() on demand.
+    let resolveStart!: () => void;
+    const startGate = new Promise<void>((res) => {
+      resolveStart = res;
+    });
+    const be = new FakeBackend();
+    be.startGate = startGate;
+    const { ctrl } = makeCtrl({ backendFactory: () => be });
+
+    // Kick off ensureStarted but DO NOT await — start() is parked on the gate.
+    const startedP = ctrl.ensureStarted();
+    // Let the ensureStarted IIFE run up to `await backend.start()`.
+    await Promise.resolve();
+    await Promise.resolve();
+    expect(be.startCalls).toBe(1); // start() was entered and is now pending
+
+    // Caller tears the controller down while start() is still in flight
+    // (a user `!stop`/disconnect). Pre-fix this.backend is still null so this
+    // is a no-op and the spawned sidecar is orphaned.
+    ctrl.stop();
+
+    // Now let start() finally resolve. Pre-fix the IIFE would set this.backend
+    // and started=true, RESURRECTING the sidecar the caller already stopped.
+    resolveStart();
+    const result = await startedP;
+
+    // Post-fix: the mid-flight backend is torn down, not promoted.
+    expect(result).toBe(false);
+    expect(be.stopCalls).toBeGreaterThanOrEqual(1); // the fake WAS stopped
+    expect(be.listenerCount("trackEnded")).toBe(0); // listeners detached
+    expect(() => ctrl.getPcmStream()).toThrow(); // not resurrected
+  });
+});
+
+describe("SpotifyController per-bot ports (Fix 3)", () => {
+  it("threads apiPort + callbackPort into the default GoLibrespotBackend", async () => {
+    goLibrespotCtor.mockClear();
+    // No injected backendFactory → the controller builds the (mocked) real backend.
+    const ctrl = new SpotifyController({
+      config: cfg(),
+      workDir: "/tmp/work",
+      configDir: "/tmp/cfg",
+      logger: silentLogger,
+      apiPort: 3712,
+      callbackPort: 8712,
+    });
+    expect(await ctrl.ensureStarted()).toBe(true);
+    expect(goLibrespotCtor).toHaveBeenCalledWith(
+      expect.objectContaining({ apiPort: 3712, callbackPort: 8712 }),
+    );
+  });
+});
+
+describe("perBotDeviceName (corner-case R2-5)", () => {
+  it("suffixes the base name with the instanceId", () => {
+    expect(perBotDeviceName("TSMusicBot", "bot1")).toBe("TSMusicBot-bot1");
+  });
+  it("returns the base name unchanged when no instanceId is given", () => {
+    expect(perBotDeviceName("TSMusicBot", undefined)).toBe("TSMusicBot");
+  });
+});
+
+describe("SpotifyController per-bot device name (corner-case R2-5)", () => {
+  it("applies the per-bot suffix to the backend deviceName when instanceId is set", async () => {
+    goLibrespotCtor.mockClear();
+    // No injected backendFactory → the controller builds the (mocked) real backend.
+    const ctrl = new SpotifyController({
+      config: cfg(),
+      workDir: "/tmp/work",
+      configDir: "/tmp/cfg",
+      logger: silentLogger,
+      instanceId: "bot1",
+    });
+    expect(await ctrl.ensureStarted()).toBe(true);
+    // The Connect identity is UNIQUE per bot ("<base>-<id>") so two bots under
+    // one account never register the same name (misroute / false-readiness).
+    expect(goLibrespotCtor).toHaveBeenCalledWith(
+      expect.objectContaining({ deviceName: "TSMusicBot-bot1" }),
+    );
+  });
+
+  it("leaves the base deviceName unchanged when no instanceId (behavior-preserving)", async () => {
+    goLibrespotCtor.mockClear();
+    const ctrl = new SpotifyController({
+      config: cfg(),
+      workDir: "/tmp/work",
+      configDir: "/tmp/cfg",
+      logger: silentLogger,
+    });
+    expect(await ctrl.ensureStarted()).toBe(true);
+    expect(goLibrespotCtor).toHaveBeenCalledWith(
+      expect.objectContaining({ deviceName: "TSMusicBot" }),
+    );
+  });
+});
+
+describe("SpotifyController.chooseBackend (platform x config matrix)", () => {
+  function pick(
+    backend: SpotifyConfig["backend"],
+    opts: { go: boolean; goSupported?: boolean; rust: boolean; rustSupported?: boolean },
+  ) {
+    bin.supported = opts.goSupported ?? true;
+    bin.path = opts.go ? existingBin : missingBin;
+    bin.rustSupported = opts.rustSupported ?? true;
+    bin.rustPath = opts.rust ? existingBin : missingBin;
+    const { ctrl } = makeCtrl({ config: { backend } });
+    return ctrl.chooseBackend();
+  }
+
+  it("auto: prefers go-librespot when linux + go binary present", () => {
+    expect(pick("auto", { go: true, rust: true })).toBe("go-librespot");
+  });
+  it("auto: falls back to librespot when go unsupported (e.g. Windows) but librespot present", () => {
+    expect(pick("auto", { go: true, goSupported: false, rust: true })).toBe("librespot");
+  });
+  it("auto: falls back to librespot when go binary is absent", () => {
+    expect(pick("auto", { go: false, rust: true })).toBe("librespot");
+  });
+  it("auto: null when neither backend is usable", () => {
+    expect(pick("auto", { go: false, goSupported: false, rust: false })).toBeNull();
+  });
+  it("go-librespot: selected when supported + present", () => {
+    expect(pick("go-librespot", { go: true, rust: true })).toBe("go-librespot");
+  });
+  it("go-librespot: null when unsupported, even if librespot is present", () => {
+    expect(pick("go-librespot", { go: true, goSupported: false, rust: true })).toBeNull();
+  });
+  it("librespot: selected when the librespot binary is present", () => {
+    expect(pick("librespot", { go: true, rust: true })).toBe("librespot");
+  });
+  it("librespot: null when the librespot binary is absent, even if go is present", () => {
+    expect(pick("librespot", { go: true, rust: false })).toBeNull();
+  });
+});
+
+describe("SpotifyController Rust-backend auth gate", () => {
+  it("isAvailable is true for a present librespot binary regardless of auth", () => {
+    bin.rustPath = existingBin;
+    const { ctrl } = makeCtrl({
+      config: { backend: "librespot" },
+      oauth: fakeOAuth(false),
+    });
+    expect(ctrl.isAvailable()).toBe(true);
+  });
+
+  it("ensureStarted returns false (no backend built) when Rust chosen but unauthorized", async () => {
+    bin.rustPath = existingBin;
+    let built = 0;
+    const { ctrl } = makeCtrl({
+      config: { backend: "librespot" },
+      oauth: fakeOAuth(false),
+      backendFactory: () => {
+        built++;
+        return new FakeBackend();
+      },
+    });
+    expect(await ctrl.ensureStarted()).toBe(false);
+    expect(built).toBe(0);
+  });
+
+  it("ensureStarted starts the Rust backend once authorized", async () => {
+    bin.rustPath = existingBin;
+    const be = new FakeBackend();
+    let built = 0;
+    const { ctrl } = makeCtrl({
+      config: { backend: "librespot" },
+      oauth: fakeOAuth(true),
+      backendFactory: () => {
+        built++;
+        return be;
+      },
+    });
+    expect(await ctrl.ensureStarted()).toBe(true);
+    expect(built).toBe(1);
+    expect(be.startCalls).toBe(1);
+  });
+
+  it("go-librespot path never consults oauth.isAuthorized()", async () => {
+    // auto + go present -> go-librespot; the auth gate must be skipped so a
+    // throwing isAuthorized() is never reached.
+    const oauth = fakeOAuth(false, {
+      onIsAuthorized: () => {
+        throw new Error("isAuthorized must not be called on the go path");
+      },
+    });
+    const { ctrl } = makeCtrl({ config: { backend: "auto" }, oauth });
+    expect(await ctrl.ensureStarted()).toBe(true);
+  });
+
+  it("exposes the shared oauth + connect instances", () => {
+    const oauth = fakeOAuth(true);
+    const { ctrl } = makeCtrl({ config: { backend: "auto" }, oauth });
+    expect(ctrl.getOAuth()).toBe(oauth);
+    expect(ctrl.getConnect()).toBeDefined();
+  });
+});

src/music/spotify/controller.ts

@@ -0,0 +1,405 @@
+import { EventEmitter } from "node:events";
+import {
+  existsSync,
+  readFileSync,
+  writeFileSync,
+  mkdirSync,
+  rmSync,
+} from "node:fs";
+import { dirname, join } from "node:path";
+import type { Readable } from "node:stream";
+import type { Logger } from "pino";
+import type { SpotifyConfig } from "../../data/config.js";
+import type {
+  SpotifyAudioBackend,
+  SpotifyTrackEndedEvent,
+  SpotifyNowPlaying,
+} from "./backend.js";
+import { isGoLibrespotPresent, isLibrespotPresent } from "./binary.js";
+import { GoLibrespotBackend } from "./go-librespot.js";
+import { RustLibrespotBackend } from "./rust-librespot.js";
+import {
+  SpotifyOAuth,
+  type OAuthTokens,
+  type OAuthTokenStore,
+} from "./spotify-oauth.js";
+import { SpotifyConnectApi } from "./connect-api.js";
+import {
+  resolveSpotifyBackendKind,
+  type SpotifyBackendKind,
+} from "./backend-select.js";
+export type { SpotifyBackendKind }; // keep the name exported for existing importers
+
+/**
+ * Derive the per-bot Spotify Connect device name from the user-configured base.
+ *
+ * `config.spotify` is a single process-wide object shared by every BotInstance,
+ * so `config.spotify.deviceName` is identical for all bots. On the Rust
+ * (librespot) backend each bot would otherwise spawn `librespot --name <base>`
+ * with NO uniqueness, registering TWO Connect devices with the SAME name under
+ * the one shared Premium account — so `findDeviceByName` / `waitForDevice`
+ * (which match by name) could target the OTHER bot's device, misrouting
+ * transfer()+play() and reporting false readiness (corner-case R2-5).
+ *
+ * Suffixing the base with the bot's instanceId makes the Connect identity
+ * unique per bot. Pure + deterministic: same inputs → same name across
+ * restarts. Returns the base unchanged when no instanceId is supplied (keeps
+ * existing single-bot / non-injected behavior byte-for-byte).
+ */
+export function perBotDeviceName(base: string, instanceId?: string): string {
+  return instanceId ? `${base}-${instanceId}` : base;
+}
+
+/**
+ * Minimal file-backed OAuth token store used when the caller does not inject a
+ * SpotifyOAuth. Persists the rotating refresh-token JSON next to the bot config
+ * (0600). All IO is lazy + guarded so construction never throws and a
+ * missing/corrupt file simply reads as "unauthorized".
+ */
+class FileOAuthTokenStore implements OAuthTokenStore {
+  constructor(private readonly file: string) {}
+  load(): OAuthTokens | null {
+    try {
+      if (!existsSync(this.file)) return null;
+      return JSON.parse(readFileSync(this.file, "utf8")) as OAuthTokens;
+    } catch {
+      return null;
+    }
+  }
+  save(t: OAuthTokens): void {
+    mkdirSync(dirname(this.file), { recursive: true });
+    writeFileSync(this.file, JSON.stringify(t), { mode: 0o600 });
+  }
+  clear(): void {
+    try {
+      rmSync(this.file, { force: true });
+    } catch {
+      /* ignore */
+    }
+  }
+}
+
+export interface SpotifyControllerOptions {
+  config: SpotifyConfig;
+  workDir: string;
+  configDir: string;
+  logger: Logger;
+  /** Owning bot's id; suffixed onto the shared base deviceName so each bot's
+   *  Spotify Connect identity is unique (avoids multi-bot device collision /
+   *  misroute — corner-case R2-5). Omitted → the base name is used unchanged. */
+  instanceId?: string;
+  /** Per-bot go-librespot control-API port (distinct per bot to avoid binds). */
+  apiPort?: number;
+  /** Per-bot go-librespot OAuth callback port (distinct per bot). */
+  callbackPort?: number;
+  /** Injected for tests; when set it overrides the per-kind default builders. */
+  backendFactory?: () => SpotifyAudioBackend;
+  /** Injected for tests; defaults to a file-backed SpotifyOAuth in configDir. */
+  oauth?: SpotifyOAuth;
+  /** Injected for tests; defaults to a SpotifyConnectApi wired to oauth. */
+  connect?: SpotifyConnectApi;
+}
+
+/**
+ * Per-bot orchestrator for the Spotify sidecar. Selects a backend for this
+ * host+config (chooseBackend), owns backend lifecycle, gates on availability
+ * (config + platform + binary) plus — for the Rust librespot backend — OAuth
+ * authorization, delegates transport, and re-emits "trackEnded"/"metadata" so
+ * BotInstance can advance the queue exactly as for the ffmpeg path.
+ *
+ * Correction C3 (unchanged): this controller does NOT re-emit a raw "error"
+ * event. It subscribes to the backend's "error", logs it, tears the backend
+ * down, and marks itself not-ready so the next ensureStarted() relaunches a
+ * fresh backend. getPcmStream() proxies the backend's SINGLE persistent stream.
+ */
+export class SpotifyController extends EventEmitter {
+  private readonly config: SpotifyConfig;
+  private readonly workDir: string;
+  private readonly configDir: string;
+  private readonly logger: Logger;
+  private readonly instanceId?: string;
+  private readonly apiPort?: number;
+  private readonly callbackPort?: number;
+  private readonly injectedFactory?: () => SpotifyAudioBackend;
+  private readonly oauth: SpotifyOAuth;
+  private readonly connect: SpotifyConnectApi;
+
+  private backend: SpotifyAudioBackend | null = null;
+  // The in-flight backend during a start() that has not yet completed. A
+  // stop()/handleBackendError() DURING start() clears (or replaces) this so the
+  // mid-start sidecar is torn down and a completing start is discarded by the
+  // ensureStarted post-await guard instead of resurrecting a backend the caller
+  // already tore down (Bug I1).
+  private pendingBackend: SpotifyAudioBackend | null = null;
+  private started = false;
+  private startPromise: Promise<boolean> | null = null;
+
+  constructor(o: SpotifyControllerOptions) {
+    super();
+    this.config = o.config;
+    this.workDir = o.workDir;
+    this.configDir = o.configDir;
+    this.logger = o.logger;
+    this.instanceId = o.instanceId;
+    this.apiPort = o.apiPort;
+    this.callbackPort = o.callbackPort;
+    this.injectedFactory = o.backendFactory;
+    // The controller OWNS a shared OAuth + Connect pair (Task 6 web router and
+    // the Rust backend reuse these exact instances). Constructing the defaults
+    // performs no IO/network — the file store loads lazily on first use.
+    this.oauth =
+      o.oauth ??
+      new SpotifyOAuth({
+        store: new FileOAuthTokenStore(
+          join(this.configDir, "spotify-oauth.json"),
+        ),
+      });
+    this.connect =
+      o.connect ??
+      new SpotifyConnectApi(() => this.oauth.getAccessToken(), {
+        logger: this.logger,
+      });
+  }
+
+  /** Shared OAuth client (web router + Rust backend reuse this instance). */
+  getOAuth(): SpotifyOAuth {
+    return this.oauth;
+  }
+
+  /** Shared Connect API client (Rust backend reuses this instance). */
+  getConnect(): SpotifyConnectApi {
+    return this.connect;
+  }
+
+  private goPresent(): boolean {
+    // PATH-aware, sync presence gate (Bug I3): a bare PATH-installed binary is
+    // resolved against $PATH, not existsSync()'d against process.cwd().
+    return isGoLibrespotPresent();
+  }
+
+  private rustPresent(): boolean {
+    return isLibrespotPresent();
+  }
+
+  /**
+   * Resolve which backend to run for this platform + config, or null when none
+   * is usable (caller falls back to the Stage-1 sentinel message):
+   *   "go-librespot" -> GoLibrespot iff supported (linux) + binary present
+   *   "librespot"    -> Rust iff librespot(.exe) present (all platforms)
+   *   "auto"         -> GoLibrespot when (linux + go binary), else Rust when
+   *                     librespot present, else null.
+   */
+  chooseBackend(): SpotifyBackendKind | null {
+    return resolveSpotifyBackendKind(
+      this.config.backend,
+      this.goPresent(),
+      this.rustPresent(),
+    );
+  }
+
+  /** enabled in config AND a backend is selectable (platform + binary present). */
+  isAvailable(): boolean {
+    return this.config.enabled && this.chooseBackend() !== null;
+  }
+
+  /** Build the concrete backend for the chosen kind (or the injected fake). */
+  private buildBackend(kind: SpotifyBackendKind): SpotifyAudioBackend {
+    if (this.injectedFactory) return this.injectedFactory();
+    // Compute the effective (per-bot-unique) Connect device name ONCE and pass
+    // the SAME value to whichever backend we build, so `librespot --name`,
+    // findDeviceByName(), and waitForDevice() all key on one identity — that
+    // consistency is what prevents the multi-bot misroute / false-readiness
+    // (corner-case R2-5). The user-configured base (config.deviceName) is left
+    // untouched; the suffix is applied only to the backend/Connect identity.
+    const deviceName = perBotDeviceName(this.config.deviceName, this.instanceId);
+    if (kind === "librespot") {
+      return new RustLibrespotBackend({
+        deviceName,
+        bitrate: this.config.bitrate,
+        cacheDir: join(this.workDir, "librespot-cache"),
+        oauth: this.oauth,
+        connect: this.connect,
+        logger: this.logger,
+      });
+    }
+    return new GoLibrespotBackend({
+      deviceName,
+      bitrate: this.config.bitrate,
+      workDir: this.workDir,
+      configDir: this.configDir,
+      apiPort: this.apiPort,
+      callbackPort: this.callbackPort,
+      logger: this.logger,
+    });
+  }
+
+  /**
+   * Idempotently start the selected backend. Returns false (without building a
+   * backend) when unavailable, or — for the Rust backend — when OAuth is not
+   * yet authorized, so callers show the login-needed / fallback message. A
+   * failed start clears the cached promise so a later call can retry.
+   */
+  async ensureStarted(): Promise<boolean> {
+    if (!this.isAvailable()) return false;
+    const kind = this.chooseBackend();
+    if (!kind) return false;
+    // The Rust librespot device only appears in Spotify Connect once the user
+    // has authorized OAuth; without it, do not spawn a dead sidecar.
+    if (kind === "librespot" && !this.oauth.isAuthorized()) return false;
+
+    if (this.started) {
+      if (this.backend?.isReady()) return true;
+      this.stop();
+    }
+    if (this.startPromise) return this.startPromise;
+
+    this.startPromise = (async () => {
+      const backend = this.buildBackend(kind);
+      // Publish the in-flight backend BEFORE the (potentially ~20s) start()
+      // await so a concurrent stop()/handleBackendError() can reach and tear
+      // down this mid-start sidecar (Bug I1).
+      this.pendingBackend = backend;
+      backend.on("trackEnded", (e: SpotifyTrackEndedEvent) =>
+        this.emit("trackEnded", e),
+      );
+      backend.on("metadata", (m: SpotifyNowPlaying) =>
+        this.emit("metadata", m),
+      );
+      // C3: do NOT re-emit "error". Log and mark not-ready so the next
+      // ensureStarted() relaunches a fresh backend.
+      backend.on("error", (err?: unknown) => this.handleBackendError(err));
+      try {
+        await backend.start();
+      } catch (err) {
+        this.logger.error({ err }, "Spotify backend failed to start");
+        if (this.pendingBackend === backend) this.pendingBackend = null;
+        this.startPromise = null;
+        return false;
+      }
+      // Post-await guard (Bug I1): if teardown ran DURING start() — stop() or
+      // handleBackendError() cleared/replaced pendingBackend — do NOT promote
+      // this backend. Tear the just-started sidecar down so it is neither
+      // leaked nor resurrected, and report failure to the caller.
+      if (this.pendingBackend !== backend) {
+        this.teardownBackend(
+          backend,
+          "Spotify backend stop() threw tearing down a superseded start",
+        );
+        return false;
+      }
+      this.pendingBackend = null;
+      this.backend = backend;
+      this.started = true;
+      return true;
+    })();
+    return this.startPromise;
+  }
+
+  /**
+   * Stop a backend and detach ALL its listeners, swallowing+logging any throw
+   * from stop() so teardown never propagates. Shared by the error/stop paths
+   * and the ensureStarted post-await guard.
+   */
+  private teardownBackend(be: SpotifyAudioBackend, stopMsg: string): void {
+    try {
+      be.stop();
+    } catch (stopErr) {
+      this.logger.error({ err: stopErr }, stopMsg);
+    }
+    (be as unknown as EventEmitter).removeAllListeners();
+  }
+
+  /**
+   * Tear down an in-flight (mid-start) backend so a start() still awaiting is
+   * discarded by ensureStarted's post-await guard rather than promoted, and its
+   * spawned sidecar is killed rather than orphaned (Bug I1).
+   */
+  private teardownPendingBackend(): void {
+    if (!this.pendingBackend) return;
+    this.teardownBackend(
+      this.pendingBackend,
+      "Spotify backend stop() threw tearing down in-flight start",
+    );
+    this.pendingBackend = null;
+  }
+
+  /**
+   * C3 backend-error handler. Never re-emits "error" (an unhandled "error" on
+   * an EventEmitter throws). Logs, tears the errored backend down, and marks
+   * the controller not-ready so the next ensureStarted() relaunches it.
+   */
+  private handleBackendError(err: unknown): void {
+    this.logger.error({ err }, "Spotify backend error; marking not-ready");
+    if (this.backend) {
+      this.teardownBackend(
+        this.backend,
+        "Spotify backend stop() threw during error teardown",
+      );
+    }
+    this.backend = null;
+    // Also kill an in-flight start so its post-await guard discards it.
+    this.teardownPendingBackend();
+    this.started = false;
+    this.startPromise = null;
+  }
+
+  /** Ensure started, then play the spotify: URI. False on any failure. */
+  async playTrack(uri: string): Promise<boolean> {
+    const ok = await this.ensureStarted();
+    if (!ok || !this.backend) return false;
+    try {
+      await this.backend.playTrack(uri);
+      return true;
+    } catch (err) {
+      this.logger.error({ err, uri }, "Spotify playTrack failed");
+      return false;
+    }
+  }
+
+  async pause(): Promise<void> {
+    if (this.backend) await this.backend.pause();
+  }
+
+  async resume(): Promise<void> {
+    if (this.backend) await this.backend.resume();
+  }
+
+  async seek(ms: number): Promise<void> {
+    // R4-1: round to an integer ms ONCE here so BOTH backends receive a valid
+    // integer position. The web progress bar computes seekTime = ratio *
+    // duration (fractional seconds), so seek(seconds * 1000) is a NON-integer ms
+    // (e.g. 71610.00000000001). go-librespot decodes `position` into an int64
+    // and Go's encoding/json rejects a JSON number with a decimal point → HTTP
+    // 400 → the error is swallowed → the track never seeks. The Spotify Web API
+    // (Rust path) likewise expects an integer position_ms. Clamp negatives to 0.
+    const position = Math.max(0, Math.round(ms));
+    if (this.backend) await this.backend.seek(position);
+  }
+
+  getPcmStream(): Readable {
+    if (!this.backend) {
+      throw new Error("Spotify backend not started");
+    }
+    return this.backend.getPcmStream();
+  }
+
+  /**
+   * Tear down the backend and reset lifecycle state (safe before start).
+   * Mirrors handleBackendError's teardown so the NEXT ensureStarted() rebuilds
+   * a fresh backend.
+   */
+  stop(): void {
+    if (this.backend) {
+      this.teardownBackend(
+        this.backend,
+        "Spotify backend stop() threw during teardown",
+      );
+    }
+    this.backend = null;
+    // Also kill an in-flight start so its post-await guard discards it rather
+    // than resurrecting the sidecar this stop() just tore down (Bug I1).
+    this.teardownPendingBackend();
+    this.started = false;
+    this.startPromise = null;
+  }
+}

src/music/spotify/go-librespot-api.test.ts

@@ -0,0 +1,299 @@
+import { describe, it, expect, vi, beforeEach } from "vitest";
+import { EventEmitter } from "node:events";
+import type { AxiosInstance } from "axios";
+import { GoLibrespotRestClient, GoLibrespotEventClient } from "./go-librespot-api.js";
+
+/** Minimal axios stub: only get/post are exercised by the client. */
+function makeHttp(overrides?: Partial<Record<"get" | "post", any>>) {
+  return {
+    get: vi.fn().mockResolvedValue({ status: 200, data: {} }),
+    post: vi.fn().mockResolvedValue({ status: 200, data: {} }),
+    ...overrides,
+  } as unknown as AxiosInstance;
+}
+
+describe("GoLibrespotRestClient", () => {
+  it("ping() returns true on GET / -> 200", async () => {
+    const http = makeHttp();
+    const client = new GoLibrespotRestClient("http://127.0.0.1:3678", { http });
+    await expect(client.ping()).resolves.toBe(true);
+    expect(http.get).toHaveBeenCalledWith("/");
+  });
+
+  it("ping() returns false when GET / rejects (daemon not up)", async () => {
+    const http = makeHttp({ get: vi.fn().mockRejectedValue(new Error("ECONNREFUSED")) });
+    const client = new GoLibrespotRestClient("http://127.0.0.1:3678", { http });
+    await expect(client.ping()).resolves.toBe(false);
+  });
+
+  it("playTrack() POSTs /player/play with the uri body", async () => {
+    const http = makeHttp();
+    const client = new GoLibrespotRestClient("http://127.0.0.1:3678", { http });
+    await client.playTrack("spotify:track:abc123");
+    expect(http.post).toHaveBeenCalledWith("/player/play", { uri: "spotify:track:abc123" });
+  });
+
+  it("pause/resume/stop POST their bodyless endpoints", async () => {
+    const http = makeHttp();
+    const client = new GoLibrespotRestClient("http://127.0.0.1:3678", { http });
+    await client.pause();
+    await client.resume();
+    await client.stop();
+    expect(http.post).toHaveBeenNthCalledWith(1, "/player/pause");
+    expect(http.post).toHaveBeenNthCalledWith(2, "/player/resume");
+    expect(http.post).toHaveBeenNthCalledWith(3, "/player/stop");
+  });
+
+  it("seek() POSTs /player/seek with position(ms) and relative:false", async () => {
+    const http = makeHttp();
+    const client = new GoLibrespotRestClient("http://127.0.0.1:3678", { http });
+    await client.seek(42000);
+    expect(http.post).toHaveBeenCalledWith("/player/seek", { position: 42000, relative: false });
+  });
+
+  it("playTrack() rejects when the POST fails (surfaced to caller)", async () => {
+    const http = makeHttp({ post: vi.fn().mockRejectedValue(new Error("boom")) });
+    const client = new GoLibrespotRestClient("http://127.0.0.1:3678", { http });
+    await expect(client.playTrack("spotify:track:x")).rejects.toThrow("boom");
+  });
+
+  it("getStatus() normalizes the /status shape (ms position/duration)", async () => {
+    const http = makeHttp({
+      get: vi.fn().mockResolvedValue({
+        status: 200,
+        data: {
+          stopped: false,
+          paused: false,
+          buffering: false,
+          track: {
+            uri: "spotify:track:abc",
+            name: "Song",
+            artist_names: ["A", "B"],
+            album_name: "Alb",
+            album_cover_url: "https://i.scdn.co/c.jpg",
+            position: 12345,
+            duration: 200000,
+          },
+        },
+      }),
+    });
+    const client = new GoLibrespotRestClient("http://127.0.0.1:3678", { http });
+    const status = await client.getStatus();
+    expect(http.get).toHaveBeenCalledWith("/status");
+    expect(status).toEqual({
+      stopped: false,
+      paused: false,
+      buffering: false,
+      track: {
+        uri: "spotify:track:abc",
+        name: "Song",
+        artist_names: ["A", "B"],
+        album_name: "Alb",
+        album_cover_url: "https://i.scdn.co/c.jpg",
+        position: 12345,
+        duration: 200000,
+      },
+    });
+  });
+
+  it("getStatus() returns null with a null track when nothing is loaded", async () => {
+    const http = makeHttp({ get: vi.fn().mockResolvedValue({ status: 200, data: { stopped: true, paused: false, buffering: false, track: null } }) });
+    const client = new GoLibrespotRestClient("http://127.0.0.1:3678", { http });
+    const status = await client.getStatus();
+    expect(status).toEqual({ stopped: true, paused: false, buffering: false, track: null });
+  });
+
+  it("getStatus() returns null when GET /status rejects", async () => {
+    const http = makeHttp({ get: vi.fn().mockRejectedValue(new Error("down")) });
+    const client = new GoLibrespotRestClient("http://127.0.0.1:3678", { http });
+    await expect(client.getStatus()).resolves.toBeNull();
+  });
+});
+
+/** Fake ws: records instances, lets tests drive open/message/close/error. */
+class FakeWebSocket extends EventEmitter {
+  static instances: FakeWebSocket[] = [];
+  closed = false;
+  constructor(public url: string) {
+    super();
+    FakeWebSocket.instances.push(this);
+  }
+  close() {
+    this.closed = true;
+    this.emit("close");
+  }
+}
+
+function frame(type: string, data: unknown): Buffer {
+  return Buffer.from(JSON.stringify({ type, data }));
+}
+
+describe("GoLibrespotEventClient", () => {
+  beforeEach(() => {
+    FakeWebSocket.instances = [];
+  });
+
+  it("emits 'not_playing' (track-end) with its data payload", () => {
+    const client = new GoLibrespotEventClient("ws://127.0.0.1:3678/events", {
+      WebSocketCtor: FakeWebSocket as any,
+    });
+    const onEnded = vi.fn();
+    client.on("not_playing", onEnded);
+    client.start();
+
+    const ws = FakeWebSocket.instances[0];
+    expect(ws.url).toBe("ws://127.0.0.1:3678/events");
+    ws.emit("message", frame("not_playing", { uri: "spotify:track:abc", play_origin: "go-librespot" }));
+
+    expect(onEnded).toHaveBeenCalledTimes(1);
+    expect(onEnded).toHaveBeenCalledWith({ uri: "spotify:track:abc", play_origin: "go-librespot" });
+    client.stop();
+  });
+
+  it("emits 'metadata' with the now-playing object", () => {
+    const client = new GoLibrespotEventClient("ws://127.0.0.1:3678/events", {
+      WebSocketCtor: FakeWebSocket as any,
+    });
+    const onMeta = vi.fn();
+    client.on("metadata", onMeta);
+    client.start();
+
+    FakeWebSocket.instances[0].emit(
+      "message",
+      frame("metadata", { uri: "spotify:track:xyz", name: "Song", artist_names: ["Q"], duration: 200000 }),
+    );
+
+    expect(onMeta).toHaveBeenCalledWith({ uri: "spotify:track:xyz", name: "Song", artist_names: ["Q"], duration: 200000 });
+    client.stop();
+  });
+
+  it("ignores non-JSON frames without throwing", () => {
+    const client = new GoLibrespotEventClient("ws://x/events", { WebSocketCtor: FakeWebSocket as any });
+    const onAny = vi.fn();
+    client.on("metadata", onAny);
+    client.start();
+    expect(() => FakeWebSocket.instances[0].emit("message", Buffer.from("not json"))).not.toThrow();
+    expect(onAny).not.toHaveBeenCalled();
+    client.stop();
+  });
+
+  it("reconnects with backoff after the socket closes", () => {
+    vi.useFakeTimers();
+    try {
+      const client = new GoLibrespotEventClient("ws://x/events", { WebSocketCtor: FakeWebSocket as any });
+      client.start();
+      expect(FakeWebSocket.instances).toHaveLength(1);
+
+      FakeWebSocket.instances[0].emit("close");
+      expect(FakeWebSocket.instances).toHaveLength(1); // not immediate
+      vi.advanceTimersByTime(500);
+      expect(FakeWebSocket.instances).toHaveLength(2); // reconnected
+      client.stop();
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+
+  it("stop() closes the socket and prevents reconnect", () => {
+    vi.useFakeTimers();
+    try {
+      const client = new GoLibrespotEventClient("ws://x/events", { WebSocketCtor: FakeWebSocket as any });
+      client.start();
+      const ws = FakeWebSocket.instances[0];
+      client.stop();
+      expect(ws.closed).toBe(true);
+      vi.advanceTimersByTime(60000);
+      expect(FakeWebSocket.instances).toHaveLength(1); // no new socket
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+
+  it("does not throw on socket 'error' when no error listener is attached", () => {
+    const client = new GoLibrespotEventClient("ws://x/events", { WebSocketCtor: FakeWebSocket as any });
+    client.start();
+    expect(() => FakeWebSocket.instances[0].emit("error", new Error("net"))).not.toThrow();
+    client.stop();
+  });
+
+  // R4-3: a WS drop at a track boundary can lose the not_playing/stopped event.
+  // After a successful RE-open the client emits "reconnected" so the backend can
+  // re-query GET /status and reconcile. The FIRST connect must NOT emit it (there
+  // is nothing to reconcile yet).
+  it("emits 'reconnected' after a reconnect open, but NOT on the initial connect", () => {
+    vi.useFakeTimers();
+    try {
+      const client = new GoLibrespotEventClient("ws://x/events", { WebSocketCtor: FakeWebSocket as any });
+      const onReconnected = vi.fn();
+      client.on("reconnected", onReconnected);
+      client.start();
+
+      FakeWebSocket.instances[0].emit("open"); // initial connect
+      expect(onReconnected).not.toHaveBeenCalled(); // no re-sync on first connect
+
+      FakeWebSocket.instances[0].emit("close");
+      vi.advanceTimersByTime(500);
+      expect(FakeWebSocket.instances).toHaveLength(2); // reconnected socket
+      FakeWebSocket.instances[1].emit("open"); // reconnect open
+      expect(onReconnected).toHaveBeenCalledTimes(1);
+      client.stop();
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+
+  // R4-5: a socket that is accepted then immediately closed (a flap) must let the
+  // exponential backoff GROW — the old code reset it to 500ms on every 'open',
+  // pinning reconnects at ~2 Hz.
+  it("grows the reconnect backoff across open→immediate-close flaps (no 500ms pin)", () => {
+    vi.useFakeTimers();
+    try {
+      const client = new GoLibrespotEventClient("ws://x/events", { WebSocketCtor: FakeWebSocket as any });
+      client.start();
+      // Flap #1: accept then immediately drop -> next reconnect at 500ms.
+      FakeWebSocket.instances[0].emit("open");
+      FakeWebSocket.instances[0].emit("close");
+      vi.advanceTimersByTime(500);
+      expect(FakeWebSocket.instances).toHaveLength(2);
+
+      // Flap #2: accept then immediately drop -> backoff has doubled to 1000ms.
+      FakeWebSocket.instances[1].emit("open");
+      FakeWebSocket.instances[1].emit("close");
+      vi.advanceTimersByTime(500);
+      expect(FakeWebSocket.instances).toHaveLength(2); // still 2: 500ms is NOT enough now
+      vi.advanceTimersByTime(500);
+      expect(FakeWebSocket.instances).toHaveLength(3); // reconnects only after 1000ms
+      client.stop();
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+
+  // R4-5: once a connection has been STABLE (up for >= STABLE_CONNECTION_MS) the
+  // backoff resets, so a later drop reconnects promptly again.
+  it("resets the reconnect backoff after a stable connection", () => {
+    vi.useFakeTimers();
+    try {
+      const client = new GoLibrespotEventClient("ws://x/events", { WebSocketCtor: FakeWebSocket as any });
+      client.start();
+      // Flap once to grow the backoff to 1000ms.
+      FakeWebSocket.instances[0].emit("open");
+      FakeWebSocket.instances[0].emit("close");
+      vi.advanceTimersByTime(500);
+      expect(FakeWebSocket.instances).toHaveLength(2);
+
+      // Now a STABLE connection: open and stay up past the stability threshold.
+      FakeWebSocket.instances[1].emit("open");
+      vi.advanceTimersByTime(5000); // >= STABLE_CONNECTION_MS -> backoff reset to 500
+
+      FakeWebSocket.instances[1].emit("close");
+      vi.advanceTimersByTime(499);
+      expect(FakeWebSocket.instances).toHaveLength(2); // not yet
+      vi.advanceTimersByTime(1);
+      expect(FakeWebSocket.instances).toHaveLength(3); // reconnected at 500ms -> backoff was reset
+      client.stop();
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+});

src/music/spotify/go-librespot-api.ts

@@ -0,0 +1,235 @@
+import { EventEmitter } from "node:events";
+import axios, { type AxiosInstance } from "axios";
+import WebSocket from "ws";
+
+export interface GoLibrespotStatusTrack {
+  uri: string;
+  name: string;
+  artist_names: string[];
+  album_name: string;
+  album_cover_url: string | null;
+  position: number;
+  duration: number;
+}
+
+export interface GoLibrespotStatus {
+  stopped: boolean;
+  paused: boolean;
+  buffering: boolean;
+  track: GoLibrespotStatusTrack | null;
+}
+
+export class GoLibrespotRestClient {
+  private http: AxiosInstance;
+
+  constructor(baseUrl: string, deps?: { http?: AxiosInstance }) {
+    this.http =
+      deps?.http ??
+      axios.create({
+        baseURL: baseUrl,
+        timeout: 10000,
+        headers: { "Content-Type": "application/json" },
+      });
+  }
+
+  async ping(): Promise<boolean> {
+    try {
+      const res = await this.http.get("/");
+      return res.status === 200;
+    } catch {
+      return false;
+    }
+  }
+
+  async playTrack(uri: string): Promise<void> {
+    await this.http.post("/player/play", { uri });
+  }
+
+  async pause(): Promise<void> {
+    await this.http.post("/player/pause");
+  }
+
+  async resume(): Promise<void> {
+    await this.http.post("/player/resume");
+  }
+
+  async stop(): Promise<void> {
+    await this.http.post("/player/stop");
+  }
+
+  async seek(ms: number): Promise<void> {
+    await this.http.post("/player/seek", { position: ms, relative: false });
+  }
+
+  async getStatus(): Promise<GoLibrespotStatus | null> {
+    try {
+      const res = await this.http.get("/status");
+      const d = res.data ?? {};
+      const t = d.track;
+      return {
+        stopped: Boolean(d.stopped),
+        paused: Boolean(d.paused),
+        buffering: Boolean(d.buffering),
+        track: t
+          ? {
+              uri: t.uri ?? "",
+              name: t.name ?? "",
+              artist_names: Array.isArray(t.artist_names) ? t.artist_names : [],
+              album_name: t.album_name ?? "",
+              album_cover_url: t.album_cover_url ?? null,
+              position: t.position ?? 0,
+              duration: t.duration ?? 0,
+            }
+          : null,
+      };
+    } catch {
+      return null;
+    }
+  }
+}
+
+export type GoLibrespotEventType =
+  | "metadata"
+  | "playing"
+  | "paused"
+  | "not_playing"
+  | "stopped"
+  | "will_play"
+  | "seek"
+  | "active"
+  | "inactive"
+  | "volume"
+  | "playback_ready";
+
+interface WsLike {
+  on(event: string, cb: (...args: any[]) => void): void;
+  close(): void;
+}
+type WebSocketCtor = new (url: string) => WsLike;
+
+const INITIAL_RECONNECT_MS = 500;
+const MAX_RECONNECT_MS = 10000;
+// R4-5: a connection must stay up at least this long before we treat it as
+// "stable" and reset the reconnect backoff. A socket that is accepted and then
+// immediately closed (a flap) never reaches this, so the exponential backoff
+// keeps growing instead of pinning the reconnect interval at INITIAL_RECONNECT_MS.
+const STABLE_CONNECTION_MS = 5000;
+
+/**
+ * Emitted (in addition to the go-librespot event types) after the socket has
+ * SUCCESSFULLY re-opened following a drop — never on the very first connect.
+ * Consumers use it to re-query GET /status and reconcile any track-end that was
+ * emitted by go-librespot during the WS-down window (R4-3).
+ */
+export type GoLibrespotSyntheticEvent = "reconnected";
+
+export class GoLibrespotEventClient extends EventEmitter {
+  private wsUrl: string;
+  private WebSocketCtor: WebSocketCtor;
+  private ws: WsLike | null = null;
+  private stopped = false;
+  private reconnectDelay = INITIAL_RECONNECT_MS;
+  private reconnectTimer: ReturnType<typeof setTimeout> | null = null;
+  // R4-3: false until the FIRST successful open. A later open is therefore a
+  // reconnect and warrants a "reconnected" re-sync signal.
+  private hasConnected = false;
+  // R4-5: fires STABLE_CONNECTION_MS after an open; only then is the backoff reset.
+  private stableTimer: ReturnType<typeof setTimeout> | null = null;
+
+  constructor(wsUrl: string, deps?: { WebSocketCtor?: WebSocketCtor }) {
+    super();
+    this.wsUrl = wsUrl;
+    this.WebSocketCtor = deps?.WebSocketCtor ?? (WebSocket as unknown as WebSocketCtor);
+  }
+
+  start(): void {
+    this.stopped = false;
+    this.connect();
+  }
+
+  stop(): void {
+    this.stopped = true;
+    this.clearStableTimer();
+    if (this.reconnectTimer) {
+      clearTimeout(this.reconnectTimer);
+      this.reconnectTimer = null;
+    }
+    if (this.ws) {
+      this.ws.close();
+      this.ws = null;
+    }
+  }
+
+  private connect(): void {
+    if (this.stopped) return;
+    const ws = new this.WebSocketCtor(this.wsUrl);
+    this.ws = ws;
+    ws.on("open", () => this.onOpen());
+    ws.on("message", (buf: unknown) => this.handleMessage(buf));
+    ws.on("close", () => {
+      this.ws = null;
+      // R4-5: the connection is gone — cancel the pending stability reset so a
+      // short-lived (flapping) socket never resets the backoff.
+      this.clearStableTimer();
+      this.scheduleReconnect();
+    });
+    ws.on("error", (err: unknown) => {
+      if (this.listenerCount("error") > 0) this.emit("error", err);
+    });
+  }
+
+  private onOpen(): void {
+    // R4-3: only a RE-open (a socket that had connected before, then dropped)
+    // needs reconciliation; the initial connect has nothing to catch up on.
+    const isReconnect = this.hasConnected;
+    this.hasConnected = true;
+    // R4-5: do NOT reset the backoff here. Arm a timer that resets it only once
+    // the connection has stayed up for STABLE_CONNECTION_MS; a flap that closes
+    // before then leaves the exponential backoff to keep growing.
+    this.armStableTimer();
+    if (isReconnect) this.emit("reconnected");
+  }
+
+  private armStableTimer(): void {
+    this.clearStableTimer();
+    this.stableTimer = setTimeout(() => {
+      this.stableTimer = null;
+      this.reconnectDelay = INITIAL_RECONNECT_MS;
+    }, STABLE_CONNECTION_MS);
+    (this.stableTimer as { unref?: () => void }).unref?.();
+  }
+
+  private clearStableTimer(): void {
+    if (this.stableTimer) {
+      clearTimeout(this.stableTimer);
+      this.stableTimer = null;
+    }
+  }
+
+  private handleMessage(buf: unknown): void {
+    let parsed: unknown;
+    try {
+      const text = Buffer.isBuffer(buf)
+        ? buf.toString("utf8")
+        : typeof buf === "string"
+          ? buf
+          : String(buf);
+      parsed = JSON.parse(text);
+    } catch {
+      return;
+    }
+    if (parsed && typeof (parsed as any).type === "string") {
+      this.emit((parsed as any).type, (parsed as any).data ?? {});
+    }
+  }
+
+  private scheduleReconnect(): void {
+    if (this.stopped || this.reconnectTimer) return;
+    const delay = this.reconnectDelay;
+    this.reconnectDelay = Math.min(delay * 2, MAX_RECONNECT_MS);
+    this.reconnectTimer = setTimeout(() => {
+      this.reconnectTimer = null;
+      this.connect();
+    }, delay);
+  }
+}

src/music/spotify/go-librespot-config.test.ts

@@ -0,0 +1,119 @@
+// src/music/spotify/go-librespot-config.test.ts
+import { describe, it, expect } from "vitest";
+import { renderConfigYml, type GoLibrespotConfigOptions } from "./go-librespot-config.js";
+
+const OPTS: GoLibrespotConfigOptions = {
+  deviceName: "TeamSpeak Music Bot",
+  bitrate: 320,
+  fifoPath: "/tmp/go-librespot.fifo",
+  apiAddress: "0.0.0.0",
+  apiPort: 3678,
+  callbackPort: 8080,
+};
+
+/**
+ * Minimal 2-level YAML reader for the exact shape renderConfigYml emits
+ * (flat scalars + one level of nesting under `server:` / `credentials:`).
+ * Avoids adding a yaml dependency while still proving the output round-trips.
+ */
+function parseTinyYaml(src: string): Record<string, unknown> {
+  const root: Record<string, unknown> = {};
+  const stack: Array<{ indent: number; obj: Record<string, unknown> }> = [
+    { indent: -1, obj: root },
+  ];
+  for (const rawLine of src.split("\n")) {
+    if (rawLine.trim() === "") continue;
+    const indent = rawLine.length - rawLine.trimStart().length;
+    const line = rawLine.trim();
+    const idx = line.indexOf(":");
+    const key = line.slice(0, idx).trim();
+    let valRaw = line.slice(idx + 1).trim();
+    while (stack.length > 1 && indent <= stack[stack.length - 1].indent) {
+      stack.pop();
+    }
+    const parent = stack[stack.length - 1].obj;
+    if (valRaw === "") {
+      const child: Record<string, unknown> = {};
+      parent[key] = child;
+      stack.push({ indent, obj: child });
+      continue;
+    }
+    let val: unknown = valRaw;
+    if (valRaw.startsWith('"') && valRaw.endsWith('"')) val = JSON.parse(valRaw);
+    else if (valRaw === "true") val = true;
+    else if (valRaw === "false") val = false;
+    else if (/^-?\d+$/.test(valRaw)) val = Number(valRaw);
+    parent[key] = val;
+  }
+  return root;
+}
+
+describe("renderConfigYml", () => {
+  it("emits the exact top-level go-librespot keys/values", () => {
+    const lines = renderConfigYml(OPTS).split("\n");
+    expect(lines).toContain('device_name: "TeamSpeak Music Bot"');
+    expect(lines).toContain("device_type: computer");
+    expect(lines).toContain("bitrate: 320");
+    expect(lines).toContain("audio_backend: pipe");
+    expect(lines).toContain("audio_output_pipe: /tmp/go-librespot.fifo");
+    expect(lines).toContain("audio_output_pipe_format: s16le");
+  });
+
+  it("emits a server block with enabled/address/port set explicitly", () => {
+    const parsed = parseTinyYaml(renderConfigYml(OPTS));
+    expect(parsed.server).toEqual({
+      enabled: true,
+      address: "0.0.0.0",
+      port: 3678,
+    });
+  });
+
+  it("emits interactive OAuth credentials with the callback port", () => {
+    const parsed = parseTinyYaml(renderConfigYml(OPTS));
+    expect(parsed.credentials).toEqual({
+      type: "interactive",
+      interactive: { callback_port: 8080 },
+    });
+  });
+
+  it("full round-trip reflects every provided option", () => {
+    const parsed = parseTinyYaml(renderConfigYml(OPTS));
+    expect(parsed).toEqual({
+      device_name: "TeamSpeak Music Bot",
+      device_type: "computer",
+      bitrate: 320,
+      audio_backend: "pipe",
+      audio_output_pipe: "/tmp/go-librespot.fifo",
+      audio_output_pipe_format: "s16le",
+      server: { enabled: true, address: "0.0.0.0", port: 3678 },
+      credentials: { type: "interactive", interactive: { callback_port: 8080 } },
+    });
+  });
+
+  it("threads distinct option values through unchanged (no hard-coded ports)", () => {
+    const parsed = parseTinyYaml(
+      renderConfigYml({
+        deviceName: "Other Bot",
+        bitrate: 160,
+        fifoPath: "/run/librespot/pipe",
+        apiAddress: "127.0.0.1",
+        apiPort: 4000,
+        callbackPort: 9099,
+      }),
+    );
+    expect(parsed).toMatchObject({
+      device_name: "Other Bot",
+      bitrate: 160,
+      audio_output_pipe: "/run/librespot/pipe",
+      server: { address: "127.0.0.1", port: 4000 },
+      credentials: { interactive: { callback_port: 9099 } },
+    });
+  });
+
+  it("safely quotes device names containing special characters", () => {
+    const yml = renderConfigYml({ ...OPTS, deviceName: 'My "Cool" Bot' });
+    expect(yml.split("\n")).toContain('device_name: "My \\"Cool\\" Bot"');
+    // and still round-trips back to the original string
+    expect(parseTinyYaml(yml).device_name).toBe('My "Cool" Bot');
+  });
+});

src/music/spotify/go-librespot-config.ts

@@ -0,0 +1,42 @@
+// src/music/spotify/go-librespot-config.ts
+// Hand-built go-librespot config.yml. Keys/values verified against
+// devgianlu/go-librespot cmd/daemon/cli_config.go koanf tags. No yaml
+// dependency is used; the file is a small, fixed-shape document.
+
+export interface GoLibrespotConfigOptions {
+  deviceName: string;
+  bitrate: number;
+  fifoPath: string;
+  apiAddress: string;
+  apiPort: number;
+  callbackPort: number;
+}
+
+/**
+ * Render a headless go-librespot config.yml:
+ *  - pipe audio backend writing raw 44.1kHz/s16le stereo PCM to a FIFO,
+ *  - HTTP+WebSocket control server enabled (port has NO built-in default,
+ *    so it is always written explicitly),
+ *  - interactive OAuth credentials (persisted automatically to
+ *    <config_dir>/credentials.json after first login).
+ */
+export function renderConfigYml(o: GoLibrespotConfigOptions): string {
+  return (
+    [
+      `device_name: ${JSON.stringify(o.deviceName)}`,
+      `device_type: computer`,
+      `bitrate: ${o.bitrate}`,
+      `audio_backend: pipe`,
+      `audio_output_pipe: ${o.fifoPath}`,
+      `audio_output_pipe_format: s16le`,
+      `server:`,
+      `  enabled: true`,
+      `  address: ${o.apiAddress}`,
+      `  port: ${o.apiPort}`,
+      `credentials:`,
+      `  type: interactive`,
+      `  interactive:`,
+      `    callback_port: ${o.callbackPort}`,
+    ].join("\n") + "\n"
+  );
+}

src/music/spotify/go-librespot.test.ts

@@ -0,0 +1,411 @@
+import { describe, it, expect, vi } from "vitest";
+import { EventEmitter } from "node:events";
+import { PassThrough } from "node:stream";
+import pino from "pino";
+import { GoLibrespotBackend } from "./go-librespot.js";
+
+const log = pino({ level: "silent" });
+
+/** A minimal stand-in for a spawned ChildProcess with real Readable stdout/stderr. */
+function makeFakeChild() {
+  const child: any = new EventEmitter();
+  child.stdout = new PassThrough();
+  child.stderr = new PassThrough();
+  child.kill = vi.fn();
+  return child;
+}
+
+function makeHarness(portOpts: { apiPort?: number; callbackPort?: number } = {}) {
+  const calls: string[] = [];
+  const ffmpegChild = makeFakeChild();
+  const gliChild = makeFakeChild();
+
+  const spawn = vi.fn((cmd: string, ..._rest: any[]) => {
+    const isGli = cmd.includes("go-librespot");
+    calls.push(`spawn:${isGli ? "go-librespot" : cmd}`);
+    return isGli ? gliChild : ffmpegChild;
+  });
+  const execFileSync = vi.fn((cmd: string) => {
+    calls.push(`exec:${cmd}`);
+    return Buffer.from("");
+  });
+  const writeFileSync = vi.fn(() => calls.push("write:config"));
+  const mkdirSync = vi.fn();
+  const unlinkSync = vi.fn(() => calls.push("unlink:fifo"));
+  const existsSync = vi.fn(() => false);
+
+  const rest = {
+    ping: vi.fn(async () => true),
+    playTrack: vi.fn(async () => {}),
+    pause: vi.fn(async () => {}),
+    resume: vi.fn(async () => {}),
+    stop: vi.fn(async () => {}),
+    seek: vi.fn(async () => {}),
+    getStatus: vi.fn(async () => null),
+  };
+  const events: any = new EventEmitter();
+  events.start = vi.fn(() => calls.push("ws:start"));
+  events.stop = vi.fn();
+
+  const backend = new GoLibrespotBackend({
+    deviceName: "Test Bot",
+    bitrate: 320,
+    workDir: "/tmp/work",
+    configDir: "/tmp/cfg",
+    apiPort: portOpts.apiPort ?? 3678,
+    callbackPort: portOpts.callbackPort,
+    logger: log,
+    deps: {
+      spawn,
+      execFileSync,
+      writeFileSync,
+      mkdirSync,
+      unlinkSync,
+      existsSync,
+      // C1: pin the ffmpeg command so the arg-array/order assertions below stay
+      // stable while production resolves ffmpeg via getFfmpegCommand() (which
+      // falls back to bundled ffmpeg-static when `ffmpeg` isn't on PATH).
+      ffmpegCommand: "ffmpeg",
+      findBinary: () => "/bin/go-librespot",
+      makeRest: () => rest,
+      makeEvents: () => events,
+      sleep: async () => {},
+      pollIntervalMs: 1,
+      pollTimeoutMs: 100,
+    } as any,
+  });
+
+  return { backend, calls, spawn, execFileSync, writeFileSync, existsSync, unlinkSync, rest, events, ffmpegChild, gliChild };
+}
+
+describe("GoLibrespotBackend.start", () => {
+  it("creates the FIFO with mkfifo before spawning ffmpeg, and spawns ffmpeg BEFORE go-librespot", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+
+    expect(h.execFileSync).toHaveBeenCalledWith("mkfifo", ["/tmp/work/go-librespot.fifo"]);
+    expect(h.writeFileSync).toHaveBeenCalled();
+
+    const mkfifoIdx = h.calls.indexOf("exec:mkfifo");
+    const ffmpegIdx = h.calls.indexOf("spawn:ffmpeg");
+    const gliIdx = h.calls.indexOf("spawn:go-librespot");
+    expect(mkfifoIdx).toBeGreaterThanOrEqual(0);
+    expect(ffmpegIdx).toBeGreaterThan(mkfifoIdx); // ffmpeg attaches to the FIFO first
+    expect(gliIdx).toBeGreaterThan(ffmpegIdx);     // then the writer (go-librespot)
+    expect(h.calls.indexOf("ws:start")).toBeGreaterThan(gliIdx); // WS connects last
+  });
+
+  it("passes --config_dir to go-librespot using the resolved binary path", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    expect(h.spawn).toHaveBeenCalledWith(
+      "/bin/go-librespot",
+      ["--config_dir", "/tmp/cfg"],
+      expect.anything(),
+    );
+  });
+
+  it("uses the 44100->48000 s16le ffmpeg command reading the FIFO", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    const ffmpegArgs = h.spawn.mock.calls.find((c) => c[0] === "ffmpeg")![1] as string[];
+    expect(ffmpegArgs).toEqual([
+      "-hide_banner", "-loglevel", "error",
+      "-f", "s16le", "-ar", "44100", "-ac", "2", "-i", "/tmp/work/go-librespot.fifo",
+      "-f", "s16le", "-ar", "48000", "-ac", "2", "-acodec", "pcm_s16le", "pipe:1",
+    ]);
+  });
+
+  it("emits 'ready' and reports isReady() true once the REST ping succeeds", async () => {
+    const h = makeHarness();
+    const ready = vi.fn();
+    h.backend.on("ready", ready);
+    await h.backend.start();
+    expect(h.rest.ping).toHaveBeenCalled();
+    expect(ready).toHaveBeenCalledTimes(1);
+    expect(h.backend.isReady()).toBe(true);
+  });
+
+  it("keeps polling ping() until it returns true", async () => {
+    const h = makeHarness();
+    h.rest.ping.mockResolvedValueOnce(false).mockResolvedValueOnce(false).mockResolvedValue(true);
+    await h.backend.start();
+    expect(h.rest.ping).toHaveBeenCalledTimes(3);
+    expect(h.backend.isReady()).toBe(true);
+  });
+});
+
+describe("GoLibrespotBackend config binding (Fix 1 loopback + Fix 3 ports)", () => {
+  function writtenYml(h: ReturnType<typeof makeHarness>): string {
+    const calls = h.writeFileSync.mock.calls as unknown as any[][];
+    const call = calls.find((c) => String(c[0]).endsWith("config.yml"));
+    expect(call).toBeDefined();
+    return call![1] as string;
+  }
+
+  it("binds the control API to loopback (127.0.0.1), never 0.0.0.0", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    const yml = writtenYml(h);
+    expect(yml).toContain("address: 127.0.0.1");
+    expect(yml).not.toContain("0.0.0.0");
+  });
+
+  it("threads apiPort + callbackPort into the rendered config", async () => {
+    const h = makeHarness({ apiPort: 3712, callbackPort: 8712 });
+    await h.backend.start();
+    const yml = writtenYml(h);
+    expect(yml).toContain("port: 3712");
+    expect(yml).toContain("callback_port: 8712");
+  });
+
+  it("defaults callbackPort to 8080 when unset", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    expect(writtenYml(h)).toContain("callback_port: 8080");
+  });
+});
+
+describe("GoLibrespotBackend WebSocket event mapping", () => {
+  it("maps a not_playing event to trackEnded{reason:'ended'}", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.events.emit("not_playing", { uri: "spotify:track:abc" });
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:abc", reason: "ended" });
+  });
+
+  it("maps a stopped event to trackEnded{reason:'stopped'}", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.events.emit("stopped", { uri: "spotify:track:xyz" });
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:xyz", reason: "stopped" });
+  });
+
+  it("maps a metadata event to a SpotifyNowPlaying and updates getPositionMs()", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    const meta = vi.fn();
+    h.backend.on("metadata", meta);
+    h.events.emit("metadata", {
+      uri: "spotify:track:abc",
+      name: "Song",
+      artist_names: ["A", "B"],
+      album_name: "Alb",
+      album_cover_url: "http://x/y.jpg",
+      position: 1234,
+      duration: 200000,
+    });
+    expect(meta).toHaveBeenCalledWith({
+      uri: "spotify:track:abc",
+      name: "Song",
+      artist: "A, B",
+      album: "Alb",
+      coverUrl: "http://x/y.jpg",
+      durationMs: 200000,
+    });
+    expect(h.backend.getPositionMs()).toBe(1234);
+  });
+});
+
+describe("GoLibrespotBackend transport delegation + PCM", () => {
+  it("playTrack delegates to the REST client", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    await h.backend.playTrack("spotify:track:go");
+    expect(h.rest.playTrack).toHaveBeenCalledWith("spotify:track:go");
+  });
+
+  it("pause/resume/seek delegate to the REST client and seek updates position", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    await h.backend.pause();
+    await h.backend.resume();
+    await h.backend.seek(5000);
+    expect(h.rest.pause).toHaveBeenCalled();
+    expect(h.rest.resume).toHaveBeenCalled();
+    expect(h.rest.seek).toHaveBeenCalledWith(5000);
+    expect(h.backend.getPositionMs()).toBe(5000);
+  });
+
+  it("getPcmStream() returns the ffmpeg stdout Readable", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    expect(h.backend.getPcmStream()).toBe(h.ffmpegChild.stdout);
+  });
+});
+
+describe("GoLibrespotBackend.stop", () => {
+  it("kills ffmpeg + go-librespot, stops the WS, removes the FIFO, and clears ready", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    h.existsSync.mockReturnValue(true); // FIFO now present, so stop() unlinks it
+    h.backend.stop();
+    expect(h.ffmpegChild.kill).toHaveBeenCalled();
+    expect(h.gliChild.kill).toHaveBeenCalled();
+    expect(h.events.stop).toHaveBeenCalled();
+    expect(h.unlinkSync).toHaveBeenCalledWith("/tmp/work/go-librespot.fifo");
+    expect(h.backend.isReady()).toBe(false);
+  });
+});
+
+describe("GoLibrespotBackend.start failure cleanup", () => {
+  it("tears down ffmpeg, go-librespot, and the FIFO when readiness polling never succeeds", async () => {
+    const h = makeHarness();
+    // ping() never returns true → waitUntilReady() times out → start() rejects
+    // AFTER both processes were spawned and the FIFO was created.
+    h.rest.ping.mockResolvedValue(false);
+    // FIFO present so the cleanup path unlinks it.
+    h.existsSync.mockReturnValue(true);
+
+    await expect(h.backend.start()).rejects.toThrow(/did not become ready/);
+
+    expect(h.ffmpegChild.kill).toHaveBeenCalled(); // ffmpeg killed on failed startup
+    expect(h.gliChild.kill).toHaveBeenCalled(); // go-librespot killed on failed startup
+    expect(h.unlinkSync).toHaveBeenCalledWith("/tmp/work/go-librespot.fifo"); // FIFO removed
+    expect(h.backend.isReady()).toBe(false);
+  });
+});
+
+describe("GoLibrespotBackend child-process error handling", () => {
+  it("does not throw when a child 'error' is emitted with no backend 'error' listener attached", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    // No "error" listener on the backend: an unhandled 'error' event would crash
+    // Node, so the backend must swallow+log it instead of re-emitting.
+    expect(h.backend.listenerCount("error")).toBe(0);
+    expect(() => h.ffmpegChild.emit("error", new Error("ffmpeg boom"))).not.toThrow();
+    expect(() => h.gliChild.emit("error", new Error("gli boom"))).not.toThrow();
+  });
+
+  it("re-emits a child 'error' to an attached backend 'error' listener", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    const onErr = vi.fn();
+    h.backend.on("error", onErr);
+    const err = new Error("ffmpeg boom");
+    h.ffmpegChild.emit("error", err);
+    expect(onErr).toHaveBeenCalledWith(err);
+  });
+});
+
+// Let queued microtasks (the async reconnect re-sync) settle.
+const flush = () => new Promise<void>((r) => setTimeout(r, 0));
+
+describe("GoLibrespotBackend R4-2: unexpected sidecar exit recovery", () => {
+  it("degrades to trackEnded{reason:'error'}, surfaces 'error', and stops the WS on an UNEXPECTED exit", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    await h.backend.playTrack("spotify:track:cur"); // sets the current uri
+
+    const ended = vi.fn();
+    const onErr = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.backend.on("error", onErr);
+
+    // Sidecar dies under us (nonzero exit, no stop() from us).
+    h.gliChild.emit("exit", 1, null);
+
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:cur", reason: "error" });
+    expect(onErr).toHaveBeenCalledTimes(1); // controller told -> rebuilds on next ensureStarted
+    expect(h.events.stop).toHaveBeenCalled(); // WS reconnect loop stopped (no dead-port hammer)
+    expect(h.backend.isReady()).toBe(false);
+  });
+
+  it("emits trackEnded BEFORE error so a listener that tears down still receives the skip", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    await h.backend.playTrack("spotify:track:cur");
+
+    const order: string[] = [];
+    h.backend.on("trackEnded", () => order.push("trackEnded"));
+    h.backend.on("error", () => order.push("error"));
+    h.gliChild.emit("exit", null, "SIGKILL");
+
+    expect(order).toEqual(["trackEnded", "error"]);
+  });
+
+  it("a stop()-initiated exit emits NEITHER trackEnded NOR error", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    await h.backend.playTrack("spotify:track:cur");
+
+    const ended = vi.fn();
+    const onErr = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.backend.on("error", onErr);
+
+    h.backend.stop(); // intentional teardown -> the ensuing 'exit' must be silent
+    h.gliChild.emit("exit", 0, "SIGTERM");
+
+    expect(ended).not.toHaveBeenCalled();
+    expect(onErr).not.toHaveBeenCalled();
+  });
+});
+
+describe("GoLibrespotBackend R4-3: WS reconnect re-sync", () => {
+  const notPlaying = { stopped: true, paused: false, buffering: false, track: null };
+  const stillPlaying = {
+    stopped: false,
+    paused: false,
+    buffering: false,
+    track: {
+      uri: "spotify:track:cur",
+      name: "Song",
+      artist_names: ["A"],
+      album_name: "Alb",
+      album_cover_url: null,
+      position: 1000,
+      duration: 200000,
+    },
+  };
+
+  it("re-queries GET /status on reconnect and emits trackEnded when playback is no longer active", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    await h.backend.playTrack("spotify:track:cur");
+    h.rest.getStatus.mockResolvedValue(notPlaying as any);
+
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.events.emit("reconnected");
+    await flush();
+
+    expect(h.rest.getStatus).toHaveBeenCalled();
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:cur", reason: "ended" });
+  });
+
+  it("does NOT emit a spurious trackEnded on reconnect when status shows still-playing", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    await h.backend.playTrack("spotify:track:cur");
+    h.rest.getStatus.mockResolvedValue(stillPlaying as any);
+
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.events.emit("reconnected");
+    await flush();
+
+    expect(h.rest.getStatus).toHaveBeenCalled();
+    expect(ended).not.toHaveBeenCalled();
+  });
+
+  it("re-sync is idempotent: a reconnect then a live not_playing emits trackEnded only once", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    await h.backend.playTrack("spotify:track:cur");
+    h.rest.getStatus.mockResolvedValue(notPlaying as any);
+
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.events.emit("reconnected");
+    await flush();
+    // A duplicate live event for the same track must not double-advance the queue.
+    h.events.emit("not_playing", { uri: "spotify:track:cur" });
+
+    expect(ended).toHaveBeenCalledTimes(1);
+  });
+});

src/music/spotify/go-librespot.ts

@@ -0,0 +1,402 @@
+import { EventEmitter } from "node:events";
+// The go-librespot sidecar is Linux/Docker-gated (mkfifo + Linux-only binary),
+// so the FIFO and config-dir paths are ALWAYS POSIX. Use posix.join so the
+// separators are correct on the Linux target regardless of the host OS.
+import { posix as posixPath } from "node:path";
+import type { Readable } from "node:stream";
+import type { ChildProcess } from "node:child_process";
+import {
+  execFileSync as realExecFileSync,
+  spawn as realSpawn,
+} from "node:child_process";
+import {
+  existsSync as realExistsSync,
+  mkdirSync as realMkdirSync,
+  unlinkSync as realUnlinkSync,
+  writeFileSync as realWriteFileSync,
+} from "node:fs";
+import type { Logger } from "pino";
+import type {
+  SpotifyAudioBackend,
+  SpotifyTrackEndedEvent,
+  SpotifyNowPlaying,
+} from "./backend.js";
+import { findGoLibrespot } from "./binary.js";
+import { renderConfigYml } from "./go-librespot-config.js";
+import { GoLibrespotRestClient, GoLibrespotEventClient } from "./go-librespot-api.js";
+import { getFfmpegCommand } from "../../audio/player.js";
+
+export interface GoLibrespotBackendOptions {
+  deviceName: string;
+  bitrate: number;
+  workDir: string;
+  configDir: string;
+  apiPort?: number;
+  callbackPort?: number;
+  logger: Logger;
+  deps?: GoLibrespotBackendDeps;
+}
+
+/** Injectable seams so the whole lifecycle is testable without a real binary/FIFO/network. */
+export interface GoLibrespotBackendDeps {
+  spawn?: typeof realSpawn;
+  execFileSync?: typeof realExecFileSync;
+  existsSync?: typeof realExistsSync;
+  mkdirSync?: typeof realMkdirSync;
+  unlinkSync?: typeof realUnlinkSync;
+  writeFileSync?: typeof realWriteFileSync;
+  findBinary?: () => string;
+  /**
+   * C1: override the ffmpeg command. Production resolves it via
+   * getFfmpegCommand() (bundled ffmpeg-static fallback when `ffmpeg` isn't on
+   * PATH, the Docker case); tests pin it to "ffmpeg" for stable arg assertions.
+   */
+  ffmpegCommand?: string;
+  makeRest?: (baseUrl: string) => GoLibrespotRestClient;
+  makeEvents?: (wsUrl: string) => GoLibrespotEventClient;
+  sleep?: (ms: number) => Promise<void>;
+  pollIntervalMs?: number;
+  pollTimeoutMs?: number;
+}
+
+const DEFAULT_API_PORT = 3678;
+const DEFAULT_CALLBACK_PORT = 8080;
+const FIFO_NAME = "go-librespot.fifo";
+
+export class GoLibrespotBackend extends EventEmitter implements SpotifyAudioBackend {
+  private readonly opts: GoLibrespotBackendOptions;
+  private readonly log: Logger;
+  private readonly deps: GoLibrespotBackendDeps;
+  private readonly apiPort: number;
+  private readonly callbackPort: number;
+  private readonly fifoPath: string;
+
+  private ffmpeg: ChildProcess | null = null;
+  private proc: ChildProcess | null = null;
+  private rest: GoLibrespotRestClient | null = null;
+  private events: GoLibrespotEventClient | null = null;
+  private ready = false;
+  private positionMs = 0;
+  // R4-2: distinguishes an INTENTIONAL teardown (stop()/failed start()) — where a
+  // sidecar exit is expected and must be silent — from an UNEXPECTED death that
+  // must degrade-to-skip + surface an error so the controller relaunches.
+  private stopping = false;
+  // The uri of the track currently loaded in the sidecar (set by playTrack and
+  // refreshed from metadata). Used as the trackEnded uri on an unexpected death
+  // (R4-2) and on reconnect reconciliation (R4-3).
+  private currentUri = "";
+  // At-most-one trackEnded per track. Set when we emit a track-end, cleared when
+  // a new track begins. Keeps the reconnect re-sync (R4-3) from double-emitting
+  // with a live not_playing/stopped event.
+  private endLatched = false;
+
+  constructor(o: GoLibrespotBackendOptions) {
+    super();
+    this.opts = o;
+    this.log = o.logger;
+    this.deps = o.deps ?? {};
+    this.apiPort = o.apiPort ?? DEFAULT_API_PORT;
+    this.callbackPort = o.callbackPort ?? DEFAULT_CALLBACK_PORT;
+    this.fifoPath = posixPath.join(o.workDir, FIFO_NAME);
+  }
+
+  async start(): Promise<void> {
+    // Fresh lifecycle (also covers a start() after a previous stop() on the same
+    // instance): clear the teardown flag and per-track end state.
+    this.stopping = false;
+    this.currentUri = "";
+    this.endLatched = false;
+    const spawn = this.deps.spawn ?? realSpawn;
+    const execFileSync = this.deps.execFileSync ?? realExecFileSync;
+    const existsSync = this.deps.existsSync ?? realExistsSync;
+    const mkdirSync = this.deps.mkdirSync ?? realMkdirSync;
+    const unlinkSync = this.deps.unlinkSync ?? realUnlinkSync;
+    const writeFileSync = this.deps.writeFileSync ?? realWriteFileSync;
+    const findBinary = this.deps.findBinary ?? findGoLibrespot;
+    // C1: resolve ffmpeg via the repo's getFfmpegCommand() (ffmpeg-static
+    // fallback) unless a command is injected for tests.
+    const ffmpegCommand = this.deps.ffmpegCommand ?? getFfmpegCommand();
+
+    // 1. Ensure work + config directories exist.
+    mkdirSync(this.opts.workDir, { recursive: true });
+    mkdirSync(this.opts.configDir, { recursive: true });
+
+    // 2. (Re)create the FIFO — mkfifo fails if the path already exists.
+    if (existsSync(this.fifoPath)) unlinkSync(this.fifoPath);
+    execFileSync("mkfifo", [this.fifoPath]);
+
+    // Everything past this point spawns processes / opens sockets. If any step
+    // throws (e.g. the readiness poll times out), tear down whatever was already
+    // created via stop() (kill ffmpeg + go-librespot, close WS, remove FIFO) so
+    // we don't leak child processes or leave the FIFO on disk, then rethrow.
+    try {
+      // 3. Spawn ffmpeg FIRST so the PCM reader is attached to the FIFO before
+      //    go-librespot (the writer) starts pushing raw 44.1k s16le into it.
+      //    Opening the FIFO for writing before a reader exists errors with ENXIO.
+      this.ffmpeg = spawn(
+        ffmpegCommand,
+        [
+          "-hide_banner", "-loglevel", "error",
+          "-f", "s16le", "-ar", "44100", "-ac", "2", "-i", this.fifoPath,
+          "-f", "s16le", "-ar", "48000", "-ac", "2", "-acodec", "pcm_s16le", "pipe:1",
+        ],
+        { stdio: ["ignore", "pipe", "pipe"] },
+      );
+      this.ffmpeg.stderr?.on("data", (b: Buffer) =>
+        this.log.debug({ ffmpeg: b.toString().trim() }, "ffmpeg"),
+      );
+      this.ffmpeg.on("error", (err) => this.emitError(err));
+
+      // 4. Render + write config.yml into the config dir.
+      const yml = renderConfigYml({
+        deviceName: this.opts.deviceName,
+        bitrate: this.opts.bitrate,
+        fifoPath: this.fifoPath,
+        // The go-librespot control API is UNAUTHENTICATED and the client only
+        // ever connects via 127.0.0.1; the sidecar runs in the SAME container
+        // as the bot, so bind to loopback rather than exposing it on 0.0.0.0.
+        apiAddress: "127.0.0.1",
+        apiPort: this.apiPort,
+        callbackPort: this.callbackPort,
+      });
+      writeFileSync(posixPath.join(this.opts.configDir, "config.yml"), yml, "utf8");
+
+      // 5. Spawn go-librespot AFTER ffmpeg is listening on the FIFO. Its stdout/
+      //    stderr carry the interactive OAuth URL on first run — surface via logger.
+      const bin = findBinary();
+      this.proc = spawn(bin, ["--config_dir", this.opts.configDir], {
+        stdio: ["ignore", "pipe", "pipe"],
+      });
+      const onLog = (b: Buffer) => this.log.info({ golibrespot: b.toString().trim() }, "go-librespot");
+      this.proc.stdout?.on("data", onLog);
+      this.proc.stderr?.on("data", onLog);
+      this.proc.on("error", (err) => this.emitError(err));
+      this.proc.on("exit", (code, signal) => {
+        this.ready = false;
+        this.log.warn({ code, signal }, "go-librespot exited");
+        // R4-2: a stop()-initiated exit is expected — stay silent. Any other exit
+        // is the sidecar dying under us and must be recovered.
+        if (this.stopping) return;
+        this.onUnexpectedExit(code, signal);
+      });
+
+      // 6. REST client, then poll GET / until the HTTP server answers.
+      const baseUrl = `http://127.0.0.1:${this.apiPort}`;
+      this.rest = this.deps.makeRest
+        ? this.deps.makeRest(baseUrl)
+        : new GoLibrespotRestClient(baseUrl);
+      await this.waitUntilReady();
+
+      // 7. Connect the WebSocket event stream and wire event mapping.
+      const wsUrl = `ws://127.0.0.1:${this.apiPort}/events`;
+      this.events = this.deps.makeEvents
+        ? this.deps.makeEvents(wsUrl)
+        : new GoLibrespotEventClient(wsUrl);
+      this.wireEvents(this.events);
+      this.events.start();
+
+      this.ready = true;
+      this.emit("ready");
+    } catch (e) {
+      this.stop();
+      throw e;
+    }
+  }
+
+  /**
+   * Re-emit a child-process "error" only when a consumer is listening; Node
+   * throws on an unhandled "error" event (can crash the process), so with no
+   * listener we log via the injected logger instead. Mirrors the WS client's
+   * listenerCount("error") gate in go-librespot-api.ts.
+   */
+  private emitError(err: unknown): void {
+    if (this.listenerCount("error") > 0) {
+      this.emit("error", err);
+    } else {
+      this.log.error({ err }, "go-librespot backend error (no listener)");
+    }
+  }
+
+  /**
+   * At-most-one track-end per track. The WS not_playing/stopped events, the
+   * unexpected-death degrade (R4-2) and the reconnect re-sync (R4-3) all funnel
+   * through here so a track can only advance the queue once.
+   */
+  private emitTrackEnded(e: SpotifyTrackEndedEvent): void {
+    if (this.endLatched) return;
+    this.endLatched = true;
+    this.emit("trackEnded", e);
+  }
+
+  /**
+   * R4-2: the go-librespot sidecar died without a stop() from us. Spotify
+   * auto-advance is driven ONLY by the WS trackEnded event (the player-side stall
+   * watchdog is disabled in external mode), so a silent death would stall the
+   * queue forever. Mirror the Rust I4 degrade-to-skip:
+   *  (a) emit trackEnded{reason:"error"} so BotInstance advances the queue;
+   *  (b) stop the WS reconnect loop so it stops hammering the now-dead API port;
+   *  (c) surface via emitError so the controller tears down + relaunches a fresh
+   *      backend on the next ensureStarted().
+   * trackEnded MUST be emitted BEFORE emitError: the controller's error handler
+   * removeAllListeners() on teardown, so a trackEnded emitted after would be lost.
+   */
+  private onUnexpectedExit(code: number | null, signal: NodeJS.Signals | null): void {
+    // (b) Kill the reconnect loop first — the API port is dead.
+    try {
+      this.events?.stop();
+    } catch {
+      /* ignore */
+    }
+    this.events = null;
+    // (a) Degrade-to-skip only if a track was actually loaded; a death during
+    // startup with nothing playing has no queue item to advance.
+    if (this.currentUri) {
+      this.emitTrackEnded({ uri: this.currentUri, reason: "error" });
+    }
+    // (c) Surface so the controller rebuilds.
+    this.emitError(
+      new Error(
+        `go-librespot exited unexpectedly (code=${code ?? "null"}, signal=${signal ?? "null"})`,
+      ),
+    );
+  }
+
+  /**
+   * R4-3: the WS reconnected after a drop. go-librespot only pushes events (it is
+   * never polled after startup), so a not_playing/stopped emitted during the
+   * down window is lost and the queue would stall. Re-query GET /status and, if
+   * playback is no longer active (the track ended in the gap), emit trackEnded so
+   * the queue advances. Idempotent via the end-latch (no double-emit with a live
+   * event). Only fired on a real reconnect — never the initial connect.
+   */
+  private async reconcileAfterReconnect(): Promise<void> {
+    const rest = this.rest;
+    if (!rest) return;
+    const status = await rest.getStatus();
+    // Couldn't read status — don't guess a track-end.
+    if (!status) return;
+    const active = status.track != null && !status.stopped;
+    if (!active) {
+      this.emitTrackEnded({ uri: this.currentUri, reason: "ended" });
+    }
+  }
+
+  private async waitUntilReady(): Promise<void> {
+    const sleep = this.deps.sleep ?? ((ms: number) => new Promise<void>((r) => setTimeout(r, ms)));
+    const interval = this.deps.pollIntervalMs ?? 200;
+    const timeout = this.deps.pollTimeoutMs ?? 15_000;
+    const deadline = Date.now() + timeout;
+    while (Date.now() < deadline) {
+      if (this.rest && (await this.rest.ping())) return;
+      await sleep(interval);
+    }
+    throw new Error("go-librespot API did not become ready within timeout");
+  }
+
+  private wireEvents(ev: GoLibrespotEventClient): void {
+    ev.on("metadata", (d: any) => {
+      const np: SpotifyNowPlaying = {
+        uri: typeof d?.uri === "string" ? d.uri : "",
+        name: typeof d?.name === "string" ? d.name : "",
+        artist: Array.isArray(d?.artist_names) ? d.artist_names.join(", ") : "",
+        album: typeof d?.album_name === "string" ? d.album_name : "",
+        coverUrl: typeof d?.album_cover_url === "string" ? d.album_cover_url : "",
+        durationMs: typeof d?.duration === "number" ? d.duration : 0,
+      };
+      if (typeof d?.position === "number") this.positionMs = d.position;
+      // A new track is now playing: remember it (for R4-2/R4-3) and clear the
+      // per-track end-latch so its eventual end can advance the queue.
+      if (np.uri && np.uri !== this.currentUri) {
+        this.currentUri = np.uri;
+        this.endLatched = false;
+      }
+      this.emit("metadata", np);
+    });
+    ev.on("seek", (d: any) => {
+      if (typeof d?.position === "number") this.positionMs = d.position;
+    });
+    ev.on("not_playing", (d: any) => {
+      this.emitTrackEnded({ uri: typeof d?.uri === "string" ? d.uri : "", reason: "ended" });
+    });
+    ev.on("stopped", (d: any) => {
+      this.emitTrackEnded({ uri: typeof d?.uri === "string" ? d.uri : "", reason: "stopped" });
+    });
+    // R4-3: reconcile any track-end missed while the WS was down.
+    ev.on("reconnected", () => {
+      void this.reconcileAfterReconnect();
+    });
+  }
+
+  isReady(): boolean {
+    return this.ready;
+  }
+
+  async playTrack(uri: string): Promise<void> {
+    if (!this.rest) throw new Error("go-librespot backend not started");
+    // Track what is loaded so an unexpected death (R4-2) / reconnect re-sync
+    // (R4-3) can advance the queue for the right uri, and reset the end-latch.
+    this.currentUri = uri;
+    this.endLatched = false;
+    await this.rest.playTrack(uri);
+  }
+
+  async pause(): Promise<void> {
+    if (this.rest) await this.rest.pause();
+  }
+
+  async resume(): Promise<void> {
+    if (this.rest) await this.rest.resume();
+  }
+
+  async seek(ms: number): Promise<void> {
+    if (this.rest) await this.rest.seek(ms);
+    this.positionMs = ms;
+  }
+
+  getPcmStream(): Readable {
+    const out = this.ffmpeg?.stdout;
+    if (!out) throw new Error("PCM stream unavailable (go-librespot backend not started)");
+    return out;
+  }
+
+  getPositionMs(): number {
+    return this.positionMs;
+  }
+
+  stop(): void {
+    // R4-2: mark this an INTENTIONAL teardown so the go-librespot 'exit' handler
+    // (fired by the SIGTERM below) stays silent instead of degrading-to-skip.
+    this.stopping = true;
+    this.ready = false;
+    try {
+      this.events?.stop();
+    } catch {
+      /* ignore */
+    }
+    this.events = null;
+    this.rest = null;
+    if (this.proc) {
+      try {
+        this.proc.kill("SIGTERM");
+      } catch {
+        /* ignore */
+      }
+      this.proc = null;
+    }
+    if (this.ffmpeg) {
+      try {
+        this.ffmpeg.kill("SIGTERM");
+      } catch {
+        /* ignore */
+      }
+      this.ffmpeg = null;
+    }
+    const existsSync = this.deps.existsSync ?? realExistsSync;
+    const unlinkSync = this.deps.unlinkSync ?? realUnlinkSync;
+    try {
+      if (existsSync(this.fifoPath)) unlinkSync(this.fifoPath);
+    } catch {
+      /* ignore */
+    }
+  }
+}

src/music/spotify/provider.test.ts

@@ -0,0 +1,63 @@
+import { describe, it, expect, vi } from "vitest";
+import { SpotifyProvider } from "./provider.js";
+import { SpotifyWebApi } from "./webapi.js";
+
+function fakeApi(over: Partial<SpotifyWebApi> = {}): SpotifyWebApi {
+  return {
+    hasCreds: () => true,
+    setCreds: vi.fn(),
+    search: vi.fn().mockResolvedValue({ songs: [], playlists: [], albums: [] }),
+    getTrack: vi.fn().mockResolvedValue(null),
+    getAlbumTracks: vi.fn().mockResolvedValue([]),
+    getPlaylistTracks: vi.fn().mockResolvedValue([]),
+    ...over,
+  } as unknown as SpotifyWebApi;
+}
+
+describe("SpotifyProvider", () => {
+  it("has platform 'spotify'", () => {
+    expect(new SpotifyProvider(fakeApi()).platform).toBe("spotify");
+  });
+
+  it("getSongUrl returns the spotify: sentinel, not a real URL", async () => {
+    const p = new SpotifyProvider(fakeApi());
+    const r = await p.getSongUrl("4iV5W9uYEdYUVa79Axb7Rh");
+    expect(r).toEqual({ url: "spotify:track:4iV5W9uYEdYUVa79Axb7Rh" });
+  });
+
+  it("search delegates to the web API", async () => {
+    const api = fakeApi({
+      search: vi.fn().mockResolvedValue({
+        songs: [{ id: "t1", platform: "spotify" }],
+        playlists: [],
+        albums: [],
+      }),
+    });
+    const out = await new SpotifyProvider(api).search("queen", 5);
+    expect(api.search).toHaveBeenCalledWith("queen", 5);
+    expect(out.songs[0].id).toBe("t1");
+  });
+
+  it("getAuthStatus reflects credential presence", async () => {
+    expect((await new SpotifyProvider(fakeApi({ hasCreds: () => true })).getAuthStatus()).loggedIn).toBe(true);
+    expect((await new SpotifyProvider(fakeApi({ hasCreds: () => false })).getAuthStatus()).loggedIn).toBe(false);
+  });
+
+  it("getPlaylistSongs / getAlbumSongs delegate to the web API", async () => {
+    const api = fakeApi({
+      getPlaylistTracks: vi.fn().mockResolvedValue([{ id: "p", platform: "spotify" }]),
+      getAlbumTracks: vi.fn().mockResolvedValue([{ id: "a", platform: "spotify" }]),
+    });
+    const p = new SpotifyProvider(api);
+    expect((await p.getPlaylistSongs("37i9"))[0].id).toBe("p");
+    expect((await p.getAlbumSongs("1abc"))[0].id).toBe("a");
+  });
+
+  it("no-op auth surfaces (QR expired, empty lyrics/recommend)", async () => {
+    const p = new SpotifyProvider(fakeApi());
+    expect(await p.getLyrics("x")).toEqual([]);
+    expect(await p.getRecommendPlaylists()).toEqual([]);
+    expect((await p.getQrCode()).key).toBe("");
+    expect(await p.checkQrCodeStatus("k")).toBe("expired");
+  });
+});

src/music/spotify/provider.ts

@@ -0,0 +1,86 @@
+import type {
+  MusicProvider,
+  Song,
+  SongUrlResult,
+  Playlist,
+  Album,
+  SearchResult,
+  LyricLine,
+  QrCodeResult,
+  AuthStatus,
+} from "../provider.js";
+import { SpotifyWebApi, type SpotifyCreds } from "./webapi.js";
+
+export class SpotifyProvider implements MusicProvider {
+  readonly platform = "spotify" as const;
+  private api: SpotifyWebApi;
+  private creds: SpotifyCreds = { clientId: "", clientSecret: "" };
+  private quality = "320";
+
+  constructor(api?: SpotifyWebApi) {
+    this.api = api ?? new SpotifyWebApi(() => this.creds);
+  }
+
+  setCreds(clientId: string, clientSecret: string): void {
+    this.creds = { clientId: clientId ?? "", clientSecret: clientSecret ?? "" };
+    this.api.setCreds(this.creds);
+  }
+
+  async search(query: string, limit = 20): Promise<SearchResult> {
+    return this.api.search(query, limit);
+  }
+
+  // Stage 1: return a sentinel URI. The play path recognizes `spotify:` and
+  // skips with a "not playable yet" message; real audio arrives in Stage 2/3.
+  async getSongUrl(songId: string): Promise<SongUrlResult | null> {
+    return { url: `spotify:track:${songId}` };
+  }
+
+  setQuality(quality: string): void {
+    this.quality = quality;
+  }
+  getQuality(): string {
+    return this.quality;
+  }
+
+  async getSongDetail(songId: string): Promise<Song | null> {
+    return this.api.getTrack(songId);
+  }
+
+  async getPlaylistSongs(playlistId: string): Promise<Song[]> {
+    return this.api.getPlaylistTracks(playlistId);
+  }
+
+  async getAlbumSongs(albumId: string): Promise<Song[]> {
+    return this.api.getAlbumTracks(albumId);
+  }
+
+  async getRecommendPlaylists(): Promise<Playlist[]> {
+    return [];
+  }
+
+  async getLyrics(_songId: string): Promise<LyricLine[]> {
+    return [];
+  }
+
+  async getQrCode(): Promise<QrCodeResult> {
+    return { qrUrl: "", key: "" };
+  }
+
+  async checkQrCodeStatus(
+    _key: string
+  ): Promise<"waiting" | "scanned" | "confirmed" | "expired"> {
+    return "expired";
+  }
+
+  setCookie(_cookie: string): void {}
+  getCookie(): string {
+    return "";
+  }
+
+  async getAuthStatus(): Promise<AuthStatus> {
+    return this.api.hasCreds()
+      ? { loggedIn: true, nickname: "Spotify" }
+      : { loggedIn: false, nickname: "Spotify (未配置 Client ID/Secret)" };
+  }
+}

src/music/spotify/rust-librespot.test.ts

@@ -0,0 +1,814 @@
+import { describe, it, expect, vi } from "vitest";
+import { EventEmitter } from "node:events";
+import { PassThrough } from "node:stream";
+import pino from "pino";
+import { RustLibrespotBackend, type RustLibrespotBackendDeps } from "./rust-librespot.js";
+
+const log = pino({ level: "silent" });
+
+/** ChildProcess stand-in with real Readable/Writable pipes so stdout->stdin piping works. */
+function makeFakeChild() {
+  const child: any = new EventEmitter();
+  child.stdout = new PassThrough();
+  child.stderr = new PassThrough();
+  child.stdin = new PassThrough();
+  child.kill = vi.fn();
+  return child;
+}
+
+function makeConnect() {
+  return {
+    getDevices: vi.fn(async () => [{ id: "dev1", name: "Test Bot", is_active: false }]),
+    findDeviceByName: vi.fn(async () => "dev1"),
+    transfer: vi.fn(async () => {}),
+    play: vi.fn(async () => {}),
+    pause: vi.fn(async () => {}),
+    resume: vi.fn(async () => {}),
+    seek: vi.fn(async () => {}),
+    getPlaybackState: vi.fn(async () => null as any),
+  };
+}
+
+function makeOAuth() {
+  return {
+    getAccessToken: vi.fn(async () => "tok-123" as string | null),
+    isAuthorized: () => true,
+  };
+}
+
+function makeHarness(
+  over: { connect?: any; oauth?: any; deps?: Partial<RustLibrespotBackendDeps> } = {},
+) {
+  const calls: string[] = [];
+  const librespotChild = makeFakeChild();
+  const ffmpegChild = makeFakeChild();
+
+  const spawn = vi.fn((cmd: string, ..._rest: any[]) => {
+    const isLibrespot = cmd.includes("librespot");
+    calls.push(`spawn:${isLibrespot ? "librespot" : cmd}`);
+    return isLibrespot ? librespotChild : ffmpegChild;
+  });
+  const mkdirSync = vi.fn();
+  const connect = over.connect ?? makeConnect();
+  const oauth = over.oauth ?? makeOAuth();
+
+  const backend = new RustLibrespotBackend({
+    deviceName: "Test Bot",
+    bitrate: 320,
+    cacheDir: "/tmp/cache",
+    oauth: oauth as any,
+    connect: connect as any,
+    logger: log,
+    deps: {
+      spawn: spawn as any,
+      mkdirSync: mkdirSync as any,
+      findBinary: () => "/bin/librespot",
+      // C1: pin ffmpeg so arg-array assertions stay stable while prod uses getFfmpegCommand().
+      ffmpegCommand: "ffmpeg",
+      sleep: async () => {},
+      readyPollIntervalMs: 1,
+      readyTimeoutMs: 100,
+      // huge so the background setInterval never fires; tests drive pollState() directly.
+      statePollIntervalMs: 10_000_000,
+      ...over.deps,
+    },
+  });
+
+  return { backend, calls, spawn, mkdirSync, connect, oauth, librespotChild, ffmpegChild };
+}
+
+describe("RustLibrespotBackend.start", () => {
+  it("spawns librespot with the pipe/stdout arg set and the OAuth access token", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    expect(h.spawn).toHaveBeenCalledWith(
+      "/bin/librespot",
+      [
+        "--name", "Test Bot",
+        "--backend", "pipe",
+        "--bitrate", "320",
+        "--format", "S16",
+        "--cache", "/tmp/cache",
+        "--device-type", "speaker",
+        "--access-token", "tok-123",
+      ],
+      expect.anything(),
+    );
+    // NO --device (=> stdout) and NO --passthrough (=> decoded PCM, not Ogg).
+    const args = h.spawn.mock.calls.find((c) => String(c[0]).includes("librespot"))![1] as string[];
+    expect(args).not.toContain("--device");
+    expect(args).not.toContain("--passthrough");
+    h.backend.stop();
+  });
+
+  it("spawns ffmpeg (reader) before librespot (writer) with the exact 44100->48000 s16le args", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    const ffmpegArgs = h.spawn.mock.calls.find((c) => c[0] === "ffmpeg")![1] as string[];
+    expect(ffmpegArgs).toEqual([
+      "-f", "s16le", "-ar", "44100", "-ac", "2", "-i", "pipe:0",
+      "-f", "s16le", "-ar", "48000", "-ac", "2", "-acodec", "pcm_s16le", "pipe:1",
+    ]);
+    const ffmpegIdx = h.calls.indexOf("spawn:ffmpeg");
+    const librespotIdx = h.calls.indexOf("spawn:librespot");
+    expect(ffmpegIdx).toBeGreaterThanOrEqual(0);
+    expect(librespotIdx).toBeGreaterThan(ffmpegIdx);
+    h.backend.stop();
+  });
+
+  it("getPcmStream() returns the ffmpeg stdout Readable", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    expect(h.backend.getPcmStream()).toBe(h.ffmpegChild.stdout);
+    h.backend.stop();
+  });
+
+  it("emits 'ready' and reports isReady() true once our device appears in getDevices()", async () => {
+    const h = makeHarness();
+    const ready = vi.fn();
+    h.backend.on("ready", ready);
+    await h.backend.start();
+    expect(h.connect.getDevices).toHaveBeenCalled();
+    expect(ready).toHaveBeenCalledTimes(1);
+    expect(h.backend.isReady()).toBe(true);
+    h.backend.stop();
+  });
+
+  it("keeps polling getDevices() until the device name appears", async () => {
+    const h = makeHarness();
+    h.connect.getDevices
+      .mockResolvedValueOnce([])
+      .mockResolvedValueOnce([{ id: "other", name: "Someone else", is_active: true }])
+      .mockResolvedValue([{ id: "dev1", name: "Test Bot", is_active: false }]);
+    await h.backend.start();
+    expect(h.connect.getDevices).toHaveBeenCalledTimes(3);
+    expect(h.backend.isReady()).toBe(true);
+    h.backend.stop();
+  });
+
+  it("throws (and does not spawn) when the OAuth token is null", async () => {
+    const oauth = makeOAuth();
+    oauth.getAccessToken.mockResolvedValue(null);
+    const h = makeHarness({ oauth });
+    await expect(h.backend.start()).rejects.toThrow(/authorized|token/i);
+    expect(h.spawn).not.toHaveBeenCalled();
+  });
+});
+
+describe("RustLibrespotBackend transport delegation (Connect API)", () => {
+  it("playTrack resolves the device then transfer(false) then play(uri)", async () => {
+    const h = makeHarness();
+    await h.backend.playTrack("spotify:track:go");
+    expect(h.connect.findDeviceByName).toHaveBeenCalledWith("Test Bot");
+    expect(h.connect.transfer).toHaveBeenCalledWith("dev1", false);
+    expect(h.connect.play).toHaveBeenCalledWith("dev1", "spotify:track:go");
+    // ordering: transfer before play
+    expect(h.connect.transfer.mock.invocationCallOrder[0])
+      .toBeLessThan(h.connect.play.mock.invocationCallOrder[0]);
+  });
+
+  it("playTrack throws when the device cannot be found", async () => {
+    const h = makeHarness();
+    h.connect.findDeviceByName.mockResolvedValue(null);
+    await expect(h.backend.playTrack("spotify:track:x")).rejects.toThrow(/device/i);
+  });
+
+  // R4-4 (multi-bot): control must be scoped to OUR device. playTrack resolves
+  // and stores our device id (dev1); pause/resume/seek then pass it to the
+  // Connect API so bot A's pause/resume/seek can't act on bot B's playback (the
+  // account-wide default would pause whatever device is currently active).
+  it("pause/resume/seek delegate to the Connect API scoped to OUR device, and seek updates position", async () => {
+    const h = makeHarness();
+    await h.backend.playTrack("spotify:track:go"); // stores our device id (dev1)
+    await h.backend.pause();
+    await h.backend.resume();
+    await h.backend.seek(5000);
+    expect(h.connect.pause).toHaveBeenCalledWith("dev1");
+    expect(h.connect.resume).toHaveBeenCalledWith("dev1");
+    expect(h.connect.seek).toHaveBeenCalledWith(5000, "dev1");
+    expect(h.backend.getPositionMs()).toBe(5000);
+  });
+});
+
+describe("RustLibrespotBackend track-end poll loop", () => {
+  it("emits trackEnded when progress reaches the end-of-track window", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    const meta = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.backend.on("metadata", meta);
+    // Arm detection the way production does — via our own playTrack().
+    await h.backend.playTrack("spotify:track:A");
+    h.connect.getPlaybackState
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 1000, trackUri: "spotify:track:A", durationMs: 200000 })
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 199000, trackUri: "spotify:track:A", durationMs: 200000 });
+    await (h.backend as any).pollState();
+    expect(meta).toHaveBeenCalledWith(expect.objectContaining({ uri: "spotify:track:A", durationMs: 200000 }));
+    expect(h.backend.getPositionMs()).toBe(1000);
+    expect(ended).not.toHaveBeenCalled();
+    await (h.backend as any).pollState();
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:A", reason: "ended" });
+  });
+
+  // C1(pause-skip): a USER pause reports is_playing:false with the SAME uri on
+  // the Rust backend. That MUST NOT be read as a track end (it would skip the
+  // paused track and break pause + occupancy auto-pause). Formerly the
+  // "!isPlaying after having played" test asserted the opposite — that encoded
+  // the bug; it is now split into this pause-no-skip test plus the two-poll
+  // external-stop test below.
+  it("does NOT emit trackEnded when the user PAUSES (self-initiated pause is not a track end)", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    // Observe our track actually playing first.
+    h.connect.getPlaybackState.mockResolvedValueOnce({
+      isPlaying: true, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    // User pauses: the Connect device stays loaded but reports is_playing:false
+    // with the SAME uri across every subsequent poll while paused.
+    await h.backend.pause();
+    h.connect.getPlaybackState.mockResolvedValue({
+      isPlaying: false, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    await (h.backend as any).pollState(); // stays paused across multiple polls
+    expect(ended).not.toHaveBeenCalled();
+    // Resuming keeps the same track playing — still no spurious end.
+    await h.backend.resume();
+    h.connect.getPlaybackState.mockResolvedValue({
+      isPlaying: true, progressMs: 6000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    expect(ended).not.toHaveBeenCalled();
+  });
+
+  it("emits trackEnded once on an EXTERNAL stop only after TWO consecutive !isPlaying polls (a transient mid-track !isPlaying is not a skip)", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    h.connect.getPlaybackState
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000 })
+      .mockResolvedValueOnce({ isPlaying: false, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000 })
+      .mockResolvedValue({ isPlaying: false, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000 });
+    await (h.backend as any).pollState(); // observed playing
+    await (h.backend as any).pollState(); // FIRST !isPlaying -> unconfirmed (could be transient buffering)
+    expect(ended).not.toHaveBeenCalled();
+    await (h.backend as any).pollState(); // SECOND consecutive !isPlaying -> confirmed external stop
+    await (h.backend as any).pollState(); // idempotent: no second emit for same track
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:A", reason: "ended" });
+  });
+
+  it("a transient single !isPlaying poll followed by playing again does NOT emit trackEnded (buffering hiccup)", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    h.connect.getPlaybackState
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000 })
+      .mockResolvedValueOnce({ isPlaying: false, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000 })
+      .mockResolvedValue({ isPlaying: true, progressMs: 6000, trackUri: "spotify:track:A", durationMs: 200000 });
+    await (h.backend as any).pollState(); // playing
+    await (h.backend as any).pollState(); // momentary !isPlaying (buffering)
+    await (h.backend as any).pollState(); // playing again -> stop confirmation reset
+    expect(ended).not.toHaveBeenCalled();
+  });
+
+  // m(sub-window): a track SHORTER than the end-of-track window must not be
+  // declared finished on its first observed-playing poll (durationMs - window
+  // is negative, so the old near-end check fired unconditionally).
+  it("does NOT false-finish a sub-window (< END_OF_TRACK_WINDOW_MS) duration on the first playing poll", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:short");
+    h.connect.getPlaybackState.mockResolvedValue({
+      isPlaying: true, progressMs: 100, trackUri: "spotify:track:short", durationMs: 1200,
+    });
+    await (h.backend as any).pollState();
+    expect(ended).not.toHaveBeenCalled();
+  });
+
+  // C1(pause-skip) residual: a self-initiated pause within the FINAL
+  // END_OF_TRACK_WINDOW_MS freezes progress at >= dur-window with is_playing:false
+  // and the SAME uri. The finishedByProgress near-end heuristic must NOT fire
+  // while paused (it would skip the paused track). After resume(), the track
+  // plays on and finishes exactly once.
+  it("does NOT skip when the user PAUSES within the final end-of-track window, but ends once after resume", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    // Observe our track actually playing first (mid-track).
+    h.connect.getPlaybackState.mockResolvedValueOnce({
+      isPlaying: true, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    // User pauses within the final ~1.5s: frozen progress >= dur-window,
+    // is_playing:false, SAME uri, across every subsequent paused poll.
+    await h.backend.pause();
+    h.connect.getPlaybackState.mockResolvedValue({
+      isPlaying: false, progressMs: 199000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    await (h.backend as any).pollState(); // stays paused across multiple polls
+    expect(ended).not.toHaveBeenCalled();
+    // Resume -> the track plays on to its natural end and finishes exactly once.
+    await h.backend.resume();
+    h.connect.getPlaybackState.mockResolvedValue({
+      isPlaying: true, progressMs: 199000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:A", reason: "ended" });
+  });
+
+  // C1(pause-skip) residual: during a LONG self-initiated pause the Connect
+  // device can idle out to a 204 / null playback state. That null state while
+  // paused must NOT be read as a track end (it would skip the paused track).
+  // After resume() a genuinely dead device (persistent null) IS detected.
+  it("does NOT skip a PAUSED track when the device idles out to null/204, but DOES after resume", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    // Observe our track actually playing first.
+    h.connect.getPlaybackState.mockResolvedValueOnce({
+      isPlaying: true, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    // Pause, then the Connect device idles out to a 204 / null state.
+    await h.backend.pause();
+    h.connect.getPlaybackState.mockResolvedValue(null as any);
+    await (h.backend as any).pollState();
+    await (h.backend as any).pollState(); // stays paused across multiple null polls
+    expect(ended).not.toHaveBeenCalled();
+    // Resume -> a genuinely dead device (persistent null) is now detected once.
+    await h.backend.resume();
+    await (h.backend as any).pollState();
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:A", reason: "ended" });
+  });
+
+  // Regression: a NON-paused track that idles out to a null/204 state after
+  // having played must STILL emit exactly one trackEnded (the pause gate must
+  // not suppress genuine device death for a non-paused track).
+  it("regression: a NON-paused track that idles out to null/204 after playing still emits exactly one trackEnded", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    h.connect.getPlaybackState.mockResolvedValueOnce({
+      isPlaying: true, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState(); // observed playing, not paused
+    h.connect.getPlaybackState.mockResolvedValue(null as any); // device idles out
+    await (h.backend as any).pollState();
+    await (h.backend as any).pollState(); // idempotent: no second emit
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:A", reason: "ended" });
+  });
+
+  // R3-1: a GENUINE end where the item stays null across TWO consecutive
+  // non-paused polls still emits exactly one trackEnded. The null-item path now
+  // shares the external-stop two-poll confirmation, so a single transient null
+  // (Connect handoff / market relink) no longer skips a still-playing track —
+  // but a persistent null is still detected. (Previously this test asserted a
+  // single null poll ended the track; that encoded the R3-1 corner-case bug.)
+  it("emits trackEnded once when the track uri stays null across TWO consecutive polls after playing", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    h.connect.getPlaybackState
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 1000, trackUri: "spotify:track:A", durationMs: 200000 })
+      .mockResolvedValue({ isPlaying: true, progressMs: 0, trackUri: null, durationMs: 0 });
+    await (h.backend as any).pollState(); // observed playing our uri
+    await (h.backend as any).pollState(); // FIRST null item -> unconfirmed (could be transient)
+    expect(ended).not.toHaveBeenCalled();
+    await (h.backend as any).pollState(); // SECOND consecutive null -> confirmed end
+    await (h.backend as any).pollState(); // idempotent: no second emit for same track
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:A", reason: "ended" });
+  });
+
+  // R3-1: Spotify legitimately returns item:null transiently at a track/Connect
+  // handoff boundary, and getPlaybackState omits the `market` param so a
+  // region-relinked/restricted item can momentarily map to uri:null. A SINGLE
+  // {isPlaying:true, trackUri:null} poll mid-track must NOT skip a still-playing
+  // track; a following poll showing our real uri again confirms it kept playing.
+  it("a transient single null-item poll (isPlaying:true, trackUri:null) followed by our uri again does NOT emit trackEnded", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    h.connect.getPlaybackState
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000 })
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 0, trackUri: null, durationMs: 0 })
+      .mockResolvedValue({ isPlaying: true, progressMs: 6000, trackUri: "spotify:track:A", durationMs: 200000 });
+    await (h.backend as any).pollState(); // playing our uri
+    await (h.backend as any).pollState(); // momentary null item (handoff / market relink)
+    await (h.backend as any).pollState(); // our uri again -> confirmation reset, still playing
+    expect(ended).not.toHaveBeenCalled();
+  });
+
+  // R3-1 (pause invariant): a self-paused track must NEVER skip. A {trackUri:null}
+  // poll while WE hold a pause must not be read as a track end (same invariant
+  // the finishedByStop / null-204 paths already enforce with a `!paused` guard).
+  it("does NOT emit trackEnded on a null-item poll while the track is self-paused", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    h.connect.getPlaybackState.mockResolvedValueOnce({
+      isPlaying: true, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState(); // observed playing
+    await h.backend.pause();
+    // While paused, a null item appears across multiple polls (state present, no item).
+    h.connect.getPlaybackState.mockResolvedValue({
+      isPlaying: false, progressMs: 5000, trackUri: null, durationMs: 0,
+    });
+    await (h.backend as any).pollState();
+    await (h.backend as any).pollState();
+    expect(ended).not.toHaveBeenCalled();
+  });
+
+  it("ignores a null playback state (no active device) without emitting", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.connect.getPlaybackState.mockResolvedValue(null);
+    await (h.backend as any).pollState();
+    expect(ended).not.toHaveBeenCalled();
+  });
+
+  it("C3.4: a startup poll before playTrack never emits (foreign track near its end)", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    const meta = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.backend.on("metadata", meta);
+    // Backend started, but playTrack has NOT been called => detection disarmed.
+    await h.backend.start();
+    // First poll observes a FOREIGN track that is actively playing near its end.
+    h.connect.getPlaybackState.mockResolvedValue({
+      isPlaying: true,
+      progressMs: 199000,
+      trackUri: "spotify:foreign",
+      durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    // No spurious end-of-track and no bogus metadata before the bot ever plays.
+    expect(ended).not.toHaveBeenCalled();
+    expect(meta).not.toHaveBeenCalled();
+    expect(h.backend.getPositionMs()).toBe(0);
+    h.backend.stop();
+  });
+
+  it("after playTrack, a normal finish emits trackEnded exactly once for our uri", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    // Arm detection via our own play, then confirm-then-finish our uri.
+    await h.backend.playTrack("spotify:track:ours");
+    h.connect.getPlaybackState
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 1000, trackUri: "spotify:track:ours", durationMs: 200000 })
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 199000, trackUri: "spotify:track:ours", durationMs: 200000 });
+    await (h.backend as any).pollState(); // confirms our uri playing
+    expect(ended).not.toHaveBeenCalled();
+    await (h.backend as any).pollState(); // finishes
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:ours", reason: "ended" });
+  });
+});
+
+// R4-4 (multi-bot): config.spotify (and thus the Connect session) is shared by
+// every bot under one Premium account, which supports only ONE active playback
+// stream. GET /v1/me/player is account-wide, so once bot B steals the active
+// session our poll would see B's device + B's track. The backend now stores OUR
+// device id and, when the reported activeDeviceId differs, refuses to treat the
+// foreign playback as ours: no foreign metadata, no misattribution — the stolen
+// session instead advances OUR queue cleanly via the existing two-poll stop.
+describe("RustLibrespotBackend multi-bot device scoping (R4-4)", () => {
+  it("ignores foreign-device poll state: no foreign metadata, no misattribution, and a stolen session advances OUR queue once", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    const meta = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.backend.on("metadata", meta);
+    // Our track plays on OUR device (dev1 — the findDeviceByName mock id).
+    await h.backend.playTrack("spotify:track:ours");
+    h.connect.getPlaybackState.mockResolvedValueOnce({
+      isPlaying: true, progressMs: 5000, trackUri: "spotify:track:ours",
+      durationMs: 200000, activeDeviceId: "dev1",
+    });
+    await (h.backend as any).pollState(); // our track observed playing on our device
+    expect(meta).toHaveBeenCalledTimes(1);
+    expect(meta).toHaveBeenCalledWith(expect.objectContaining({ uri: "spotify:track:ours" }));
+    expect(h.backend.getPositionMs()).toBe(5000);
+    meta.mockClear();
+    // Bot B steals the single active Connect session: /v1/me/player now reports
+    // THEIR device (dev2) + THEIR track, and would keep doing so every poll.
+    h.connect.getPlaybackState.mockResolvedValue({
+      isPlaying: true, progressMs: 123000, trackUri: "spotify:track:foreign",
+      durationMs: 200000, activeDeviceId: "dev2",
+    });
+    await (h.backend as any).pollState(); // FIRST foreign poll -> unconfirmed stop, no side effects
+    expect(meta).not.toHaveBeenCalled();            // foreign metadata NOT surfaced as ours
+    expect(ended).not.toHaveBeenCalled();            // two-poll confirmation not met yet
+    expect(h.backend.getPositionMs()).toBe(5000);    // foreign progress NOT misattributed
+    await (h.backend as any).pollState(); // SECOND foreign poll -> confirmed -> OUR queue advances
+    await (h.backend as any).pollState(); // idempotent: no second emit for our track
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:ours", reason: "ended" });
+    expect(meta).not.toHaveBeenCalled();             // never emitted metadata for the foreign uri
+  });
+
+  it("when the active device IS ours (activeDeviceId === our id), end-detection behaves exactly as today", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    h.connect.getPlaybackState
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 1000, trackUri: "spotify:track:A", durationMs: 200000, activeDeviceId: "dev1" })
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 199000, trackUri: "spotify:track:A", durationMs: 200000, activeDeviceId: "dev1" });
+    await (h.backend as any).pollState(); // confirms our uri playing on our device
+    expect(ended).not.toHaveBeenCalled();
+    await (h.backend as any).pollState(); // near-end -> finishes normally
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:A", reason: "ended" });
+  });
+});
+
+// R4-6: finishedByProgress is a SINGLE-poll near-end heuristic. If a user
+// deliberately SEEKS to within the final END_OF_TRACK_WINDOW_MS, the next poll
+// would see progressMs >= durationMs-1500 and emit trackEnded — skipping the ~1s
+// the user seeked into. A one-poll "just-seeked" grace suppresses that single
+// misfire; the track then plays its remaining <=1.5s and ends naturally on the
+// following poll via the stop/null detection. Natural near-end (reached by
+// PLAYING, no seek) must be UNCHANGED.
+describe("RustLibrespotBackend seek-into-end grace (R4-6)", () => {
+  it("does NOT skip when a seek lands within the final end-of-track window; ends naturally on the following poll", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    // Observe our track actually playing first (mid-track).
+    h.connect.getPlaybackState.mockResolvedValueOnce({
+      isPlaying: true, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    // User deliberately seeks to ~1s before the end (inside the 1.5s window).
+    await h.backend.seek(199000);
+    // First poll after the seek: progress is already inside the near-end window
+    // and still playing. The grace must suppress this single finishedByProgress.
+    h.connect.getPlaybackState.mockResolvedValueOnce({
+      isPlaying: true, progressMs: 199000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    expect(ended).not.toHaveBeenCalled();
+    // The remaining <=1.5s plays out and librespot goes idle (null/204) — the
+    // genuine end. It emits exactly one trackEnded.
+    h.connect.getPlaybackState.mockResolvedValue(null as any);
+    await (h.backend as any).pollState();
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:A", reason: "ended" });
+  });
+
+  it("the seek grace only spans ONE poll: a second in-window playing poll still finishes by progress", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    h.connect.getPlaybackState.mockResolvedValueOnce({
+      isPlaying: true, progressMs: 5000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState(); // observed playing
+    await h.backend.seek(199000); // seek into the final window
+    // Grace poll: suppressed.
+    h.connect.getPlaybackState.mockResolvedValueOnce({
+      isPlaying: true, progressMs: 199000, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    expect(ended).not.toHaveBeenCalled();
+    // Second in-window playing poll: grace already consumed -> natural near-end
+    // detection fires exactly once (grace must not permanently disable it).
+    h.connect.getPlaybackState.mockResolvedValueOnce({
+      isPlaying: true, progressMs: 199500, trackUri: "spotify:track:A", durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:A", reason: "ended" });
+  });
+
+  it("regression: a track that reaches the final window by PLAYING (no seek) still emits trackEnded on the first in-window poll", async () => {
+    const h = makeHarness();
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    await h.backend.playTrack("spotify:track:A");
+    h.connect.getPlaybackState
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 1000, trackUri: "spotify:track:A", durationMs: 200000 })
+      .mockResolvedValueOnce({ isPlaying: true, progressMs: 199000, trackUri: "spotify:track:A", durationMs: 200000 });
+    await (h.backend as any).pollState(); // observed playing (no seek)
+    expect(ended).not.toHaveBeenCalled();
+    await (h.backend as any).pollState(); // reaches window by PLAYING -> natural end
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:A", reason: "ended" });
+  });
+});
+
+describe("RustLibrespotBackend playback-start watchdog (I4 degrade-to-skip)", () => {
+  /** A controllable timer seam matching the file's injected-deps style. */
+  function makeFakeTimer() {
+    const pending: Array<{ cb: () => void; ms: number; handle: object }> = [];
+    const setTimer = vi.fn((cb: () => void, ms: number) => {
+      const handle = {};
+      pending.push({ cb, ms, handle });
+      return handle;
+    });
+    const clearTimer = vi.fn((h: unknown) => {
+      const i = pending.findIndex((p) => p.handle === h);
+      if (i >= 0) pending.splice(i, 1);
+    });
+    // "advance fake timers": run (and drain) every armed callback.
+    const advance = () => pending.splice(0).forEach((p) => p.cb());
+    return { setTimer, clearTimer, advance, pending };
+  }
+
+  it("emits exactly ONE trackEnded{reason:'error'} when playback never starts", async () => {
+    const timer = makeFakeTimer();
+    const h = makeHarness({
+      deps: {
+        playbackStartTimeoutMs: 8000,
+        setTimeout: timer.setTimer as any,
+        clearTimeout: timer.clearTimer as any,
+      },
+    });
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+
+    // The connect layer NEVER reports our track playing (204 / idle).
+    h.connect.getPlaybackState.mockResolvedValue(null);
+    await h.backend.playTrack("spotify:track:stuck");
+    // Polls that never observe playback must NOT emit anything on their own.
+    await (h.backend as any).pollState();
+    await (h.backend as any).pollState();
+    expect(ended).not.toHaveBeenCalled();
+
+    // The watchdog is armed exactly once; advance past playbackStartTimeoutMs.
+    expect(timer.pending).toHaveLength(1);
+    expect(timer.pending[0].ms).toBe(8000);
+    timer.advance();
+
+    // Degraded-to-skip: one trackEnded with reason "error" for our uri.
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:stuck", reason: "error" });
+
+    // A late idle poll after the watchdog fired does not double-emit.
+    await (h.backend as any).pollState();
+    expect(ended).toHaveBeenCalledTimes(1);
+    h.backend.stop();
+  });
+
+  it("does NOT fire the watchdog when the device actually starts playing", async () => {
+    const timer = makeFakeTimer();
+    const h = makeHarness({
+      deps: {
+        playbackStartTimeoutMs: 8000,
+        setTimeout: timer.setTimer as any,
+        clearTimeout: timer.clearTimer as any,
+      },
+    });
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+
+    await h.backend.playTrack("spotify:track:ok");
+    // Our device reports the track actually playing -> watchdog is disarmed.
+    h.connect.getPlaybackState.mockResolvedValue({
+      isPlaying: true,
+      progressMs: 1000,
+      trackUri: "spotify:track:ok",
+      durationMs: 200000,
+    });
+    await (h.backend as any).pollState();
+
+    // Real playback observed -> the watchdog was cleared, not left armed.
+    expect(timer.clearTimer).toHaveBeenCalled();
+    expect(timer.pending).toHaveLength(0);
+    // Even if a stale timer somehow fired, no "error" end must be emitted.
+    timer.advance();
+    expect(ended).not.toHaveBeenCalledWith(
+      expect.objectContaining({ reason: "error" }),
+    );
+    h.backend.stop();
+  });
+
+  it("a new playTrack() cancels the previous track's watchdog (at-most-one per track)", async () => {
+    const timer = makeFakeTimer();
+    const h = makeHarness({
+      deps: {
+        playbackStartTimeoutMs: 8000,
+        setTimeout: timer.setTimer as any,
+        clearTimeout: timer.clearTimer as any,
+      },
+    });
+    const ended = vi.fn();
+    h.backend.on("trackEnded", ended);
+    h.connect.getPlaybackState.mockResolvedValue(null);
+
+    await h.backend.playTrack("spotify:track:one");
+    await h.backend.playTrack("spotify:track:two");
+    // The first track's watchdog was cleared; only the second remains armed.
+    expect(timer.clearTimer).toHaveBeenCalled();
+    expect(timer.pending).toHaveLength(1);
+    timer.advance();
+    expect(ended).toHaveBeenCalledTimes(1);
+    expect(ended).toHaveBeenCalledWith({ uri: "spotify:track:two", reason: "error" });
+    h.backend.stop();
+  });
+});
+
+describe("RustLibrespotBackend.stop", () => {
+  it("kills librespot + ffmpeg, clears ready, and is idempotent", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    h.backend.stop();
+    h.backend.stop(); // second call must not throw
+    expect(h.librespotChild.kill).toHaveBeenCalled();
+    expect(h.ffmpegChild.kill).toHaveBeenCalled();
+    expect(h.backend.isReady()).toBe(false);
+  });
+});
+
+describe("RustLibrespotBackend.start failure cleanup", () => {
+  it("tears down librespot + ffmpeg when the device never appears", async () => {
+    const h = makeHarness();
+    h.connect.getDevices.mockResolvedValue([]); // device never shows up -> waitForDevice times out
+    await expect(h.backend.start()).rejects.toThrow(/did not appear/i);
+    expect(h.librespotChild.kill).toHaveBeenCalled();
+    expect(h.ffmpegChild.kill).toHaveBeenCalled();
+    expect(h.backend.isReady()).toBe(false);
+  });
+});
+
+describe("RustLibrespotBackend child-process error handling", () => {
+  it("swallows+logs a child 'error' when no backend 'error' listener is attached", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    expect(h.backend.listenerCount("error")).toBe(0);
+    expect(() => h.librespotChild.emit("error", new Error("boom"))).not.toThrow();
+    expect(() => h.ffmpegChild.emit("error", new Error("boom"))).not.toThrow();
+    h.backend.stop();
+  });
+
+  it("re-emits a child 'error' to an attached backend 'error' listener", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    const onErr = vi.fn();
+    h.backend.on("error", onErr);
+    const err = new Error("ffmpeg boom");
+    h.ffmpegChild.emit("error", err);
+    expect(onErr).toHaveBeenCalledWith(err);
+    h.backend.stop();
+  });
+
+  // I(pipe): ffmpeg dying mid-track while librespot keeps producing PCM raises
+  // EPIPE on ffmpeg.stdin. With no stdin 'error' listener Node escalates it to
+  // process 'uncaughtException'. The backend must handle it in-band.
+  it("swallows an EPIPE 'error' on ffmpeg.stdin (ffmpeg died mid-track) without an unhandled throw", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    expect(h.backend.listenerCount("error")).toBe(0);
+    const epipe = Object.assign(new Error("write EPIPE"), { code: "EPIPE" });
+    expect(() => h.ffmpegChild.stdin.emit("error", epipe)).not.toThrow();
+    h.backend.stop(); // idempotent second teardown must not throw
+  });
+
+  it("routes an ffmpeg.stdin EPIPE to the backend 'error' listener and tears down cleanly", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    const onErr = vi.fn();
+    h.backend.on("error", onErr);
+    const epipe = Object.assign(new Error("write EPIPE"), { code: "EPIPE" });
+    expect(() => h.ffmpegChild.stdin.emit("error", epipe)).not.toThrow();
+    expect(onErr).toHaveBeenCalledWith(epipe);
+    // Broken pipe -> clean teardown: children killed, not ready.
+    expect(h.librespotChild.kill).toHaveBeenCalled();
+    expect(h.ffmpegChild.kill).toHaveBeenCalled();
+    expect(h.backend.isReady()).toBe(false);
+    h.backend.stop(); // second teardown must not throw (no double-teardown crash)
+    expect(onErr).toHaveBeenCalledTimes(1); // single emit despite both pipe ends
+  });
+
+  it("does not throw when librespot proc.stdout emits an EPIPE on the broken pipe", async () => {
+    const h = makeHarness();
+    await h.backend.start();
+    const epipe = Object.assign(new Error("read/write EPIPE"), { code: "EPIPE" });
+    expect(() => h.librespotChild.stdout.emit("error", epipe)).not.toThrow();
+    h.backend.stop();
+  });
+});

src/music/spotify/rust-librespot.ts

@@ -0,0 +1,620 @@
+import { EventEmitter } from "node:events";
+import type { Readable } from "node:stream";
+import type { ChildProcess } from "node:child_process";
+import { spawn as realSpawn } from "node:child_process";
+import { mkdirSync as realMkdirSync } from "node:fs";
+import type { Logger } from "pino";
+import type {
+  SpotifyAudioBackend,
+  SpotifyTrackEndedEvent,
+  SpotifyNowPlaying,
+} from "./backend.js";
+import { findLibrespot } from "./binary.js";
+import { SpotifyConnectApi } from "./connect-api.js";
+import type { PlaybackState, SpotifyDevice } from "./connect-api.js";
+import type { SpotifyOAuth } from "./spotify-oauth.js";
+import { getFfmpegCommand } from "../../audio/player.js";
+
+export interface RustLibrespotBackendOptions {
+  deviceName: string;
+  bitrate: number;
+  cacheDir: string;
+  oauth: SpotifyOAuth;
+  connect?: SpotifyConnectApi;
+  logger: Logger;
+  deps?: RustLibrespotBackendDeps;
+}
+
+/** Injectable seams so the whole lifecycle is testable without a real binary/network. */
+export interface RustLibrespotBackendDeps {
+  spawn?: typeof realSpawn;
+  mkdirSync?: typeof realMkdirSync;
+  findBinary?: () => string;
+  /**
+   * C1: override the ffmpeg command. Production resolves it via
+   * getFfmpegCommand() (bundled ffmpeg-static fallback when `ffmpeg` isn't on
+   * PATH); tests pin it to "ffmpeg" for stable arg assertions.
+   */
+  ffmpegCommand?: string;
+  sleep?: (ms: number) => Promise<void>;
+  readyPollIntervalMs?: number;
+  readyTimeoutMs?: number;
+  statePollIntervalMs?: number;
+  /**
+   * I4 (§13): bounded window after playTrack() within which our own track must
+   * be observed playing, else we degrade-to-skipped (emit trackEnded
+   * reason:"error"). Injectable timer seams (default real setTimeout, unref'd)
+   * let tests advance it deterministically.
+   */
+  playbackStartTimeoutMs?: number;
+  setTimeout?: (cb: () => void, ms: number) => unknown;
+  clearTimeout?: (handle: unknown) => void;
+}
+
+const DEFAULT_READY_POLL_MS = 500;
+const DEFAULT_READY_TIMEOUT_MS = 20_000;
+const DEFAULT_STATE_POLL_MS = 2_000;
+/** How close to the end (ms) counts as "track finished" when polling player state. */
+const END_OF_TRACK_WINDOW_MS = 1_500;
+/**
+ * I4 (§13): if our own track has not been observed playing within this window
+ * after playTrack(), degrade-to-skipped so the queue advances instead of
+ * stalling on a persistently-failing play (403 non-Premium, 404 outliving
+ * retries). Bounded and injectable for tests.
+ */
+const DEFAULT_PLAYBACK_START_TIMEOUT_MS = 8_000;
+
+const defaultSleep = (ms: number) => new Promise<void>((r) => setTimeout(r, ms));
+
+export class RustLibrespotBackend extends EventEmitter implements SpotifyAudioBackend {
+  private readonly opts: RustLibrespotBackendOptions;
+  private readonly log: Logger;
+  private readonly deps: RustLibrespotBackendDeps;
+  private readonly oauth: SpotifyOAuth;
+  private readonly connect: SpotifyConnectApi;
+
+  private proc: ChildProcess | null = null;
+  private ffmpeg: ChildProcess | null = null;
+  private pollTimer: ReturnType<typeof setInterval> | null = null;
+  // I4 (§13): "did our track actually start playing?" watchdog handle (opaque —
+  // produced by the injectable setTimeout seam). null when disarmed.
+  private watchdogTimer: unknown = null;
+  private ready = false;
+  private positionMs = 0;
+
+  // R4-4 (multi-bot): OUR resolved Connect device id, captured from
+  // findDeviceByName() in playTrack(). config.spotify (hence this Connect
+  // session) is shared process-wide across every BotInstance under one Premium
+  // account, and both the control API (pause/resume/seek) and the state read
+  // (GET /v1/me/player) are ACCOUNT-wide by default. Persisting our device id
+  // lets us (a) device-scope our control commands so we only ever act on our own
+  // device, and (b) in pollState, ignore state reported for a foreign device
+  // another bot stole the single active session with. null until first playTrack.
+  private deviceId: string | null = null;
+
+  // track-end poll state machine
+  private currentUri: string | null = null;
+  private hasPlayed = false;
+  private endedForCurrent = false;
+  // C3.4: end-detection is DISARMED until our own playTrack() runs. A poll that
+  // fires before the bot ever asks to play (e.g. at startup) must produce no
+  // side effects at all, so a foreign track already near its end can't emit a
+  // spurious trackEnded/metadata and wrongly advance the queue.
+  private armed = false;
+  // C1(pause-skip): our own pause state. A self-initiated pause makes the
+  // Connect device report is_playing:false with the SAME uri; without tracking
+  // it we'd misread that as a track end and SKIP the paused track (breaking the
+  // pause command and occupancy auto-pause-when-alone on the Rust backend). Set
+  // by pause(), cleared by resume() and playTrack().
+  private paused = false;
+  // Robustness (finishedByStop + finishedByNull / R3-1): a "not clearly playing
+  // our track" signal — either a non-paused is_playing:false (external stop) OR
+  // a null item (trackUri===null) observed while our track was playing — must be
+  // confirmed across TWO consecutive non-paused polls before we emit trackEnded.
+  // Both signals can be momentary: is_playing:false from a buffering hiccup; a
+  // null item from a Connect/track handoff boundary or a region-relinked /
+  // restricted item that momentarily maps to uri:null (getPlaybackState omits
+  // the `market` param). Set on the first such poll; reset only when a poll
+  // clearly shows our track playing again (is_playing AND a real item), on track
+  // change, or on playTrack(). Sharing ONE flag keeps both sibling paths from
+  // false-skipping on a single transient poll.
+  private stopSeen = false;
+  // R4-6: one-poll "just-seeked" grace. finishedByProgress is a SINGLE-poll
+  // near-end heuristic; if a user deliberately seeks to within the final
+  // END_OF_TRACK_WINDOW_MS, the very next poll would see progressMs >=
+  // durationMs-window and emit trackEnded, SKIPPING the ~1s the user seeked
+  // into. Set by seek(); consumed on the next poll so it suppresses that single
+  // finishedByProgress misfire only — the track then plays its remaining <=1.5s
+  // and ends naturally on the following poll via the stop/null detection. It
+  // deliberately does NOT touch the paused/stop/null two-poll logic, and a track
+  // reaching the window by PLAYING (no preceding seek) still ends normally.
+  private seekGrace = false;
+  // I(pipe): one teardown per broken librespot->ffmpeg pipe. Both stream ends
+  // (ffmpeg.stdin write side, proc.stdout read side) can report the same EPIPE;
+  // this guard prevents a double teardown / double error-emit.
+  private pipeBroke = false;
+
+  constructor(o: RustLibrespotBackendOptions) {
+    super();
+    this.opts = o;
+    this.log = o.logger;
+    this.deps = o.deps ?? {};
+    this.oauth = o.oauth;
+    // The Connect API shares the backend's OAuth token source. Reuse the
+    // injected instance in tests; otherwise build one over oauth.getAccessToken().
+    this.connect = o.connect ?? new SpotifyConnectApi(() => this.oauth.getAccessToken());
+  }
+
+  async start(): Promise<void> {
+    const spawn = this.deps.spawn ?? realSpawn;
+    const mkdirSync = this.deps.mkdirSync ?? realMkdirSync;
+    const findBinary = this.deps.findBinary ?? findLibrespot;
+    // C1: resolve ffmpeg via getFfmpegCommand() unless injected for tests.
+    const ffmpegCommand = this.deps.ffmpegCommand ?? getFfmpegCommand();
+
+    // A valid USER control token is required before we spawn anything.
+    const token = await this.oauth.getAccessToken();
+    if (!token) {
+      throw new Error("Spotify not authorized (no access token) — sign in first");
+    }
+
+    mkdirSync(this.opts.cacheDir, { recursive: true });
+
+    // Everything past here spawns children / opens the state poll. On any
+    // failure (e.g. the device never appears), tear it all down via stop().
+    try {
+      this.pipeBroke = false; // fresh pipe for this start()
+      // 1. Spawn ffmpeg FIRST (the reader) so its stdin pipe is ready before
+      //    librespot starts pushing raw 44.1k s16le PCM into it.
+      this.ffmpeg = spawn(
+        ffmpegCommand,
+        [
+          "-f", "s16le", "-ar", "44100", "-ac", "2", "-i", "pipe:0",
+          "-f", "s16le", "-ar", "48000", "-ac", "2", "-acodec", "pcm_s16le", "pipe:1",
+        ],
+        { stdio: ["pipe", "pipe", "pipe"] },
+      );
+      this.ffmpeg.stderr?.on("data", (b: Buffer) =>
+        this.log.debug({ ffmpeg: b.toString().trim() }, "ffmpeg"),
+      );
+      this.ffmpeg.on("error", (err) => this.emitError(err));
+      // I(pipe): if ffmpeg dies mid-track while librespot keeps producing PCM,
+      // the next write into its stdin hits the now-closed pipe -> EPIPE 'error'
+      // on stdin. With no listener Node escalates that to process
+      // 'uncaughtException' (the global handler logs but leaves undefined
+      // state). Handle it in-band: tear down cleanly and surface via emitError.
+      this.ffmpeg.stdin?.on("error", (err) => this.onPipeError(err));
+
+      // 2. Spawn librespot: --backend pipe with NO --device => raw s16le/44100/2
+      //    on stdout, NO --passthrough (that would emit raw Ogg). --access-token
+      //    authenticates it as a Connect device controllable via the Web API.
+      const bin = findBinary();
+      this.proc = spawn(
+        bin,
+        [
+          "--name", this.opts.deviceName,
+          "--backend", "pipe",
+          "--bitrate", String(this.opts.bitrate),
+          "--format", "S16",
+          "--cache", this.opts.cacheDir,
+          "--device-type", "speaker",
+          // KNOWN LIMITATION (CWE-214): the live Spotify access token is passed in
+          // the child argv, so on a shared/multi-tenant host a co-located local
+          // process could read it via `ps` / /proc/<pid>/cmdline. Bounded (~1h token,
+          // needs local access) and `--access-token` is librespot's supported bootstrap.
+          "--access-token", token,
+        ],
+        { stdio: ["ignore", "pipe", "pipe"] },
+      );
+      // stdout carries PCM — pipe it, never attach a data listener that consumes it.
+      if (this.proc.stdout && this.ffmpeg.stdin) {
+        this.proc.stdout.pipe(this.ffmpeg.stdin);
+        // Guard the read side too: a broken pipe can surface as an 'error' on
+        // proc.stdout when ffmpeg's stdin closes underneath it. Same handler,
+        // guarded against a double teardown.
+        this.proc.stdout.on("error", (err) => this.onPipeError(err));
+      }
+      this.proc.stderr?.on("data", (b: Buffer) =>
+        this.log.info({ librespot: b.toString().trim() }, "librespot"),
+      );
+      this.proc.on("error", (err) => this.emitError(err));
+      this.proc.on("exit", (code, signal) => {
+        this.ready = false;
+        this.log.warn({ code, signal }, "librespot exited");
+      });
+
+      // 3. Poll the Connect device list until our device registers.
+      await this.waitForDevice();
+
+      // 4. Begin the player-state poll loop (track-end / position / metadata).
+      this.startPollLoop();
+
+      this.ready = true;
+      this.emit("ready");
+    } catch (e) {
+      this.stop();
+      throw e;
+    }
+  }
+
+  /**
+   * Re-emit a child "error" only when a consumer is listening; Node throws on an
+   * unhandled "error" event, so with no listener we log via the injected logger.
+   */
+  private emitError(err: unknown): void {
+    if (this.listenerCount("error") > 0) {
+      this.emit("error", err);
+    } else {
+      this.log.error({ err }, "rust-librespot backend error (no listener)");
+    }
+  }
+
+  /**
+   * I(pipe): the librespot->ffmpeg PCM pipe broke — typically ffmpeg died
+   * mid-track and librespot's next write hit the closed pipe (EPIPE), or the
+   * stream was destroyed (ERR_STREAM_DESTROYED). Both are expected teardown
+   * signals, not programming errors. Log, tear down cleanly (stop() is
+   * idempotent), then surface via emitError so a listening controller reacts.
+   * Guarded so both stream ends reporting the same break don't double-teardown.
+   */
+  private onPipeError(err: unknown): void {
+    if (this.pipeBroke) return;
+    this.pipeBroke = true;
+    this.log.warn(
+      { err },
+      "rust-librespot: librespot->ffmpeg pipe broke (ffmpeg died?) — tearing down",
+    );
+    this.stop();
+    this.emitError(err);
+  }
+
+  private async waitForDevice(): Promise<void> {
+    const sleep = this.deps.sleep ?? defaultSleep;
+    const interval = this.deps.readyPollIntervalMs ?? DEFAULT_READY_POLL_MS;
+    const timeout = this.deps.readyTimeoutMs ?? DEFAULT_READY_TIMEOUT_MS;
+    const deadline = Date.now() + timeout;
+    while (Date.now() < deadline) {
+      let devices: SpotifyDevice[] = [];
+      try {
+        devices = await this.connect.getDevices();
+      } catch (err) {
+        this.log.debug({ err }, "getDevices failed during readiness poll");
+      }
+      if (devices.some((d) => d.name === this.opts.deviceName)) return;
+      await sleep(interval);
+    }
+    throw new Error(`librespot device "${this.opts.deviceName}" did not appear within timeout`);
+  }
+
+  private startPollLoop(): void {
+    const interval = this.deps.statePollIntervalMs ?? DEFAULT_STATE_POLL_MS;
+    this.pollTimer = setInterval(() => {
+      void this.pollState();
+    }, interval);
+    // Don't keep the event loop / test process alive on account of the poll timer.
+    this.pollTimer.unref?.();
+  }
+
+  /** One player-state poll iteration: updates position/metadata and detects track end. */
+  private async pollState(): Promise<void> {
+    let state: PlaybackState | null;
+    try {
+      state = await this.connect.getPlaybackState();
+    } catch (err) {
+      this.log.debug({ err }, "getPlaybackState failed");
+      return;
+    }
+
+    // C3.4: detection is armed ONLY by our own playTrack(). Until then a poll
+    // must have NO side effects — no metadata/trackEnded emit and no mutation of
+    // currentUri/hasPlayed/positionMs. This single gate covers the null-state
+    // (C3.5 post-play-204) branch, the metadata-emit block, and every end
+    // heuristic below, so a foreign track sitting near its end at startup can
+    // never spuriously advance the queue. (Device-readiness polling via
+    // getDevices is separate and stays active regardless of this flag.)
+    if (!this.armed) return;
+
+    // R4-6: consume the one-poll "just-seeked" grace up front so it spans exactly
+    // ONE poll regardless of which branch this poll takes. `justSeeked` then
+    // suppresses a single finishedByProgress misfire below (a deliberate seek
+    // into the final END_OF_TRACK_WINDOW_MS must not be read as a natural end).
+    const justSeeked = this.seekGrace;
+    this.seekGrace = false;
+
+    if (!state) {
+      // C3.5: a 204 / no-active-device response. AFTER our own track has been
+      // seen playing, librespot going idle means the track ended — emit once so
+      // the queue advances instead of stalling. BEFORE any play (hasPlayed
+      // false), a null state is just "nothing active yet" and is ignored.
+      // C1(pause-skip) residual: while WE hold a self-initiated pause, a long
+      // pause can let the Connect device idle out to 204/null. That is still
+      // "paused", NOT a track end — do nothing this poll, or we'd skip the
+      // paused track. Once resume() clears `paused`, a genuinely-dead device
+      // (persistent null) is detected and skipped on the next poll as before.
+      if (this.hasPlayed && this.currentUri && !this.endedForCurrent && !this.paused) {
+        this.endedForCurrent = true;
+        const endedUri = this.currentUri;
+        this.currentUri = null;
+        this.positionMs = 0;
+        const e: SpotifyTrackEndedEvent = { uri: endedUri, reason: "ended" };
+        this.emit("trackEnded", e);
+      }
+      return;
+    }
+
+    // R4-4 (multi-bot): is the account's single ACTIVE Connect device ours? The
+    // Premium account allows one active playback stream, so if another bot stole
+    // the session, GET /v1/me/player now reports THAT device + its track. Only
+    // when the active device is foreign (we know our id AND the state names a
+    // DIFFERENT active id) do we refuse to treat this poll as our own track:
+    // skip metadata/track-change (so B's now-playing isn't surfaced as ours),
+    // don't advance our position/hasPlayed off foreign playback, and feed the
+    // stop/null two-poll detection so the stolen session cleanly ends OUR track
+    // and advances OUR queue instead of thrashing/misattributing. LENIENT: if
+    // our id is unknown or activeDeviceId is absent we can't tell, so we fall
+    // back to today's behavior byte-for-byte (single-bot: activeDeviceId === ours).
+    const foreignActive =
+      this.deviceId != null &&
+      state.activeDeviceId != null &&
+      state.activeDeviceId !== this.deviceId;
+
+    // Don't misattribute a foreign device's playback position as ours.
+    if (!foreignActive) this.positionMs = state.progressMs;
+
+    // Track change -> reset the end-detection state and surface best-effort
+    // metadata. Skipped entirely when a foreign device is active: its uri is NOT
+    // our track, so adopting it / emitting metadata would surface another bot's
+    // now-playing as ours and later misread that bot's stop as our track's end.
+    if (!foreignActive && state.trackUri && state.trackUri !== this.currentUri) {
+      this.currentUri = state.trackUri;
+      this.hasPlayed = false;
+      this.endedForCurrent = false;
+      this.stopSeen = false; // new track -> drop any pending stop confirmation
+      const np: SpotifyNowPlaying = {
+        uri: state.trackUri,
+        name: "",
+        artist: "",
+        album: "",
+        coverUrl: "",
+        durationMs: state.durationMs,
+      };
+      this.emit("metadata", np);
+    }
+
+    // R4-4: only OUR device actually playing counts as our track playing. When a
+    // foreign device is active, `state.isPlaying` reflects THAT bot's playback,
+    // not ours — so it must not mark hasPlayed or clear the stop confirmation.
+    const ourTrackPlaying = state.isPlaying && !foreignActive;
+    if (ourTrackPlaying) {
+      this.hasPlayed = true;
+      // Real playback observed -> the I4 degrade-to-skip watchdog is moot.
+      this.clearPlaybackWatchdog();
+    }
+    // Clearly playing our track again (is_playing AND a real item) -> any earlier
+    // transient is_playing:false (buffering) or null item (Connect handoff /
+    // market relink) was a hiccup; drop the pending two-poll end confirmation.
+    // A null item under is_playing:true is NOT "clearly playing" and must NOT
+    // reset the confirmation, or a genuine null-item end could never accumulate
+    // its second poll.
+    if (ourTrackPlaying && state.trackUri !== null) {
+      this.stopSeen = false;
+    }
+    if (!this.currentUri || this.endedForCurrent) return;
+
+    // C3.4: EVERY end condition is gated on hasPlayed so no end can fire until
+    // the bot's own track has actually been observed playing. Without this, the
+    // first poll (before playTrack) could observe the account's stale/paused
+    // track sitting near its end and spuriously emit "trackEnded".
+    // m(sub-window): only apply the near-end window when the track is LONGER
+    // than the window. For durationMs in [1, END_OF_TRACK_WINDOW_MS],
+    // `durationMs - window` is negative, so the old `> 0` guard made this
+    // unconditionally true and finished the track on its first poll. A
+    // sub-window track instead relies on normal stop/next-track detection.
+    // C1(pause-skip) residual: a self-initiated pause within the final window
+    // freezes progress at >= dur-window with is_playing:false and the SAME uri;
+    // without `!this.paused` this near-end heuristic would fire and skip the
+    // paused track. resume() clears `paused`, so a genuine natural end is still
+    // detected afterwards.
+    // R4-4: progress/duration under a foreign-active state belong to another
+    // bot's track, so the near-end heuristic must not fire off them. A stolen
+    // session ends OUR track through the stop/null two-poll path below instead.
+    const finishedByProgress =
+      this.hasPlayed &&
+      !this.paused &&
+      !foreignActive &&
+      state.durationMs > END_OF_TRACK_WINDOW_MS &&
+      state.progressMs >= state.durationMs - END_OF_TRACK_WINDOW_MS;
+    // C1(pause-skip) + R3-1(null-item): a self-initiated pause (this.paused)
+    // reports is_playing:false (and can idle to a null item) with the SAME uri —
+    // that is NOT a track end, so never finish while paused. Beyond pause, the
+    // two "not clearly playing our track" signals — an external stop
+    // (is_playing:false) and a null item (trackUri===null) — are BOTH momentary
+    // at the boundaries (buffering; Connect handoff / market relink), so they
+    // share ONE two-poll confirmation (stopSeen): require the signal to persist
+    // across two consecutive non-paused polls before ending. A single transient
+    // stop OR null is absorbed; a confirmed end still emits within ~one extra
+    // poll interval, and a genuine end (item stays null / stopped across two
+    // polls) still fires exactly once.
+    // R4-4: a foreign device becoming the active one means OUR device is no
+    // longer playing our track — the same signal as an external stop / null
+    // item, so it shares the two-poll confirmation: one foreign poll is
+    // unconfirmed (could be a transient handoff), two consecutive foreign polls
+    // cleanly end our track and advance our queue.
+    let finishedByStopOrNull = false;
+    if (
+      this.hasPlayed &&
+      !this.paused &&
+      (foreignActive || !state.isPlaying || state.trackUri === null)
+    ) {
+      if (this.stopSeen) {
+        finishedByStopOrNull = true;
+      } else {
+        this.stopSeen = true; // first such poll — await confirmation
+      }
+    }
+
+    // R4-6: a deliberate seek into the near-end window suppresses this single
+    // finishedByProgress. `justSeeked` was already consumed above, so the NEXT
+    // in-window poll finishes normally — the grace never permanently disables
+    // near-end detection, and it never touches the stop/null two-poll path.
+    if ((finishedByProgress && !justSeeked) || finishedByStopOrNull) {
+      this.endedForCurrent = true; // latch: emit at most once per track
+      const endedUri = this.currentUri;
+      this.currentUri = null;
+      this.positionMs = 0;
+      const e: SpotifyTrackEndedEvent = { uri: endedUri, reason: "ended" };
+      this.emit("trackEnded", e);
+    }
+  }
+
+  isReady(): boolean {
+    return this.ready;
+  }
+
+  async playTrack(uri: string): Promise<void> {
+    const deviceId = await this.connect.findDeviceByName(this.opts.deviceName);
+    if (!deviceId) throw new Error(`Connect device "${this.opts.deviceName}" not found`);
+    // R4-4: persist OUR device id so control (pause/resume/seek) is device-scoped
+    // and pollState can distinguish our device from a foreign one that stole the
+    // shared account's single active Connect session.
+    this.deviceId = deviceId;
+    // Reset the track-end state machine for the new track: clear the once-only
+    // latch and drop hasPlayed so no end can fire until a poll re-confirms this
+    // uri playing. currentUri is cleared so the next poll re-detects the track
+    // (fresh metadata) rather than treating it as unchanged. Arming here is the
+    // primary guarantee that no end/metadata can fire before the bot plays.
+    // Cancel the previous track's degrade-to-skip watchdog first (at-most-one
+    // trackEnded per track, I4).
+    this.clearPlaybackWatchdog();
+    this.currentUri = null;
+    this.hasPlayed = false;
+    this.endedForCurrent = false;
+    this.armed = true;
+    // A newly-started track is not paused, and carries no pending stop
+    // confirmation from the previous track. (C1 pause-skip.)
+    this.paused = false;
+    this.stopSeen = false;
+    // R4-6: a fresh track carries no pending seek grace from the previous one.
+    this.seekGrace = false;
+    // transfer(false) activates our device WITHOUT starting audio; play() then
+    // actually starts the uri. The two-step is required — transfer alone won't
+    // begin playback.
+    await this.connect.transfer(deviceId, false);
+    await this.connect.play(deviceId, uri);
+    // I4 (§13): arm the "did it actually start playing?" watchdog. If our own
+    // track is never seen playing within the window, degrade-to-skipped so the
+    // queue advances instead of hanging on a silent, persistently-failing play.
+    this.armPlaybackWatchdog(uri);
+  }
+
+  /**
+   * I4 (§13) degrade-to-skip watchdog. Arms a bounded timer; if our own track
+   * has not been observed playing by the time it fires, emit a single
+   * trackEnded{reason:"error"} so the controller re-emits it and BotInstance
+   * advances the queue. Cleared when real playback is observed, on stop(), and
+   * at the start of a new playTrack().
+   */
+  private armPlaybackWatchdog(uri: string): void {
+    this.clearPlaybackWatchdog();
+    const timeoutMs = this.deps.playbackStartTimeoutMs ?? DEFAULT_PLAYBACK_START_TIMEOUT_MS;
+    const setTimer =
+      this.deps.setTimeout ??
+      ((cb: () => void, ms: number) => {
+        const t = setTimeout(cb, ms);
+        (t as { unref?: () => void }).unref?.();
+        return t;
+      });
+    this.watchdogTimer = setTimer(() => {
+      this.watchdogTimer = null;
+      this.onPlaybackStartTimeout(uri);
+    }, timeoutMs);
+  }
+
+  private clearPlaybackWatchdog(): void {
+    if (this.watchdogTimer == null) return;
+    const clearTimer =
+      this.deps.clearTimeout ??
+      ((h: unknown) => clearTimeout(h as ReturnType<typeof setTimeout>));
+    clearTimer(this.watchdogTimer);
+    this.watchdogTimer = null;
+  }
+
+  /**
+   * Fired when the playback-start window elapses with no observed playback.
+   * C3.6: never throws up the queue path. Guarded by the same endedForCurrent
+   * latch as normal end-detection so at most one trackEnded per track (no
+   * double-emit with the poll-loop end detection).
+   */
+  private onPlaybackStartTimeout(uri: string): void {
+    // Real playback was seen (hasPlayed) or the track already ended -> moot.
+    if (this.hasPlayed || this.endedForCurrent) return;
+    this.endedForCurrent = true; // latch
+    this.currentUri = null;
+    this.positionMs = 0;
+    const e: SpotifyTrackEndedEvent = { uri, reason: "error" };
+    this.emit("trackEnded", e);
+  }
+
+  async pause(): Promise<void> {
+    // R4-4: device-scope to OUR device so bot A's pause / auto-pause-when-alone
+    // can't pause whatever device is currently active for the shared account
+    // (= bot B's playback). Falls back to account-wide only before first play.
+    await this.connect.pause(this.deviceId ?? undefined);
+    // C1(pause-skip): mark our own pause so the next poll's is_playing:false
+    // (same uri) is not misread as a track end and skipped.
+    this.paused = true;
+  }
+
+  async resume(): Promise<void> {
+    // R4-4: device-scope to OUR device (see pause()).
+    await this.connect.resume(this.deviceId ?? undefined);
+    // Resumed -> normal end-detection applies again.
+    this.paused = false;
+  }
+
+  async seek(ms: number): Promise<void> {
+    // R4-4: device-scope to OUR device (see pause()).
+    await this.connect.seek(ms, this.deviceId ?? undefined);
+    this.positionMs = ms;
+    // R4-6: arm the one-poll grace so a seek landing inside the final
+    // END_OF_TRACK_WINDOW_MS is not immediately treated as a natural end.
+    this.seekGrace = true;
+  }
+
+  getPcmStream(): Readable {
+    const out = this.ffmpeg?.stdout;
+    if (!out) throw new Error("PCM stream unavailable (rust-librespot backend not started)");
+    return out;
+  }
+
+  getPositionMs(): number {
+    return this.positionMs;
+  }
+
+  stop(): void {
+    this.ready = false;
+    // Disarm the I4 degrade-to-skip watchdog so a stopped backend never emits.
+    this.clearPlaybackWatchdog();
+    // Clear the state poll interval FIRST so no poll fires mid-teardown.
+    if (this.pollTimer) {
+      clearInterval(this.pollTimer);
+      this.pollTimer = null;
+    }
+    if (this.proc) {
+      try {
+        this.proc.kill();
+      } catch {
+        /* ignore */
+      }
+      this.proc = null;
+    }
+    if (this.ffmpeg) {
+      try {
+        this.ffmpeg.kill();
+      } catch {
+        /* ignore */
+      }
+      this.ffmpeg = null;
+    }
+  }
+}

src/music/spotify/spotify-oauth.test.ts

@@ -0,0 +1,587 @@
+import { describe, it, expect, beforeEach, afterEach, vi } from "vitest";
+import {
+  mkdtempSync,
+  rmSync,
+  readdirSync,
+  readFileSync,
+  renameSync,
+  statSync,
+} from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import {
+  SpotifyOAuth,
+  SPOTIFY_CONTROL_SCOPES,
+  generateCodeVerifier,
+  codeChallengeS256,
+  createFileOAuthTokenStore,
+  type OAuthTokens,
+  type OAuthTokenStore,
+} from "./spotify-oauth.js";
+
+// Wrap the fs functions the token store uses in call-through spies so the
+// atomic-write path (temp file + rename) can be observed/forced. Everything else
+// (mkdtemp, rmSync, readdir, …) is the real implementation via `...actual`, so
+// all other tests keep real filesystem behavior. `vi.spyOn` can't be used here
+// because the node:fs ESM namespace is non-configurable in this setup.
+vi.mock("node:fs", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("node:fs")>();
+  return {
+    ...actual,
+    writeFileSync: vi.fn(actual.writeFileSync),
+    renameSync: vi.fn(actual.renameSync),
+  };
+});
+
+// Correction C3.2: the control OAuth REQUIRES a user-provided client_id (their
+// own Spotify Developer app) + caller-supplied loopback redirect. There is NO
+// librespot public-client / :5588 default.
+const CLIENT_ID = "test-client-id";
+const REDIRECT_URI = "http://127.0.0.1:8888/api/spotify/callback";
+
+/** In-memory store exposing `.value` so tests can assert persistence. */
+function memStore(
+  initial: OAuthTokens | null = null,
+): OAuthTokenStore & { value: OAuthTokens | null } {
+  const s = {
+    value: initial,
+    load() {
+      return s.value;
+    },
+    save(t: OAuthTokens) {
+      s.value = t;
+    },
+    clear() {
+      s.value = null;
+    },
+  };
+  return s;
+}
+
+/** A manually-settled promise, to hold a token POST "in flight" during a test. */
+function deferred<T>() {
+  let resolve!: (v: T) => void;
+  let reject!: (e: unknown) => void;
+  const promise = new Promise<T>((res, rej) => {
+    resolve = res;
+    reject = rej;
+  });
+  return { promise, resolve, reject };
+}
+
+describe("PKCE helpers", () => {
+  it("generateCodeVerifier returns 64 chars from the unreserved set", () => {
+    const v = generateCodeVerifier();
+    expect(v).toHaveLength(64);
+    expect(v).toMatch(/^[A-Za-z0-9\-._~]{64}$/);
+    expect(generateCodeVerifier()).not.toBe(v); // random
+  });
+
+  it("codeChallengeS256 is base64url(sha256) with no padding (43 chars)", () => {
+    const c = codeChallengeS256("abc123");
+    expect(c).toHaveLength(43); // 32-byte digest -> 43 base64url chars
+    expect(c).not.toContain("=");
+    expect(c).toMatch(/^[A-Za-z0-9_-]+$/);
+  });
+});
+
+describe("SpotifyOAuth.buildAuthorizeUrl", () => {
+  it("builds accounts.spotify.com/authorize with the caller's clientId + redirectUri + S256", () => {
+    const oauth = new SpotifyOAuth({
+      clientId: CLIENT_ID,
+      redirectUri: REDIRECT_URI,
+      store: memStore(),
+    });
+    const { url, state } = oauth.buildAuthorizeUrl();
+    const u = new URL(url);
+    expect(u.origin + u.pathname).toBe("https://accounts.spotify.com/authorize");
+    const p = u.searchParams;
+    expect(p.get("client_id")).toBe(CLIENT_ID);
+    expect(p.get("response_type")).toBe("code");
+    expect(p.get("redirect_uri")).toBe(REDIRECT_URI);
+    expect(p.get("code_challenge_method")).toBe("S256");
+    expect(p.get("code_challenge")).toHaveLength(43);
+    expect(p.get("scope")).toBe(SPOTIFY_CONTROL_SCOPES);
+    expect(p.get("state")).toBe(state);
+    expect(state).toMatch(/^[0-9a-f]{32}$/);
+    expect(oauth.getClientId()).toBe(CLIENT_ID);
+    expect(oauth.getRedirectUri()).toBe(REDIRECT_URI);
+  });
+
+  // Correction C3.2: no clientId => cannot start OAuth; throw a clear message.
+  it("throws a clear error when clientId is empty", () => {
+    const oauth = new SpotifyOAuth({ redirectUri: REDIRECT_URI, store: memStore() });
+    expect(() => oauth.buildAuthorizeUrl()).toThrow(/Client ID/i);
+  });
+});
+
+describe("SpotifyOAuth.isAuthorized (C3.2)", () => {
+  it("is false without a clientId even if a refresh token is stored", () => {
+    const store = memStore({
+      accessToken: "a",
+      refreshToken: "r",
+      expiresAt: Date.now() + 60_000,
+      scope: "s",
+    });
+    const oauth = new SpotifyOAuth({ redirectUri: REDIRECT_URI, store });
+    expect(oauth.isAuthorized()).toBe(false);
+  });
+
+  it("is true with a clientId and a stored refresh token", () => {
+    const store = memStore({
+      accessToken: "a",
+      refreshToken: "r",
+      expiresAt: Date.now() + 60_000,
+      scope: "s",
+    });
+    const oauth = new SpotifyOAuth({ clientId: CLIENT_ID, store });
+    expect(oauth.isAuthorized()).toBe(true);
+  });
+});
+
+describe("SpotifyOAuth.handleCallback", () => {
+  it("exchanges the code (PKCE verifier matches the authorize challenge) and persists tokens", async () => {
+    const store = memStore();
+    const http = {
+      post: vi.fn().mockResolvedValue({
+        data: {
+          access_token: "a1",
+          refresh_token: "r1",
+          expires_in: 3600,
+          scope: SPOTIFY_CONTROL_SCOPES,
+        },
+      }),
+    } as any;
+    const oauth = new SpotifyOAuth({
+      clientId: CLIENT_ID,
+      redirectUri: REDIRECT_URI,
+      store,
+      deps: { http },
+    });
+
+    const { url, state } = oauth.buildAuthorizeUrl();
+    const challenge = new URL(url).searchParams.get("code_challenge")!;
+
+    const ok = await oauth.handleCallback("CODE123", state);
+    expect(ok).toBe(true);
+
+    const [path, bodyStr, cfg] = http.post.mock.calls[0];
+    expect(path).toBe("/api/token");
+    expect(cfg.headers["Content-Type"]).toBe("application/x-www-form-urlencoded");
+    const body = new URLSearchParams(bodyStr as string);
+    expect(body.get("grant_type")).toBe("authorization_code");
+    expect(body.get("code")).toBe("CODE123");
+    expect(body.get("redirect_uri")).toBe(REDIRECT_URI);
+    expect(body.get("client_id")).toBe(CLIENT_ID);
+    // The verifier sent MUST hash to the challenge advertised in the authorize URL.
+    const verifier = body.get("code_verifier")!;
+    expect(codeChallengeS256(verifier)).toBe(challenge);
+
+    expect(store.value?.accessToken).toBe("a1");
+    expect(store.value?.refreshToken).toBe("r1");
+    expect(store.value?.expiresAt).toBeGreaterThan(Date.now());
+    expect(oauth.isAuthorized()).toBe(true);
+  });
+
+  it("rejects an unknown state without calling the token endpoint (CSRF guard)", async () => {
+    const http = { post: vi.fn() } as any;
+    const oauth = new SpotifyOAuth({
+      clientId: CLIENT_ID,
+      redirectUri: REDIRECT_URI,
+      store: memStore(),
+      deps: { http },
+    });
+    expect(await oauth.handleCallback("CODE", "not-a-real-state")).toBe(false);
+    expect(http.post).not.toHaveBeenCalled();
+  });
+
+  // Correction C3.7: the state->verifier entry is deleted on EVERY terminal
+  // path (finally), so a failed login never leaks it and cannot be replayed.
+  it("deletes the pending verifier even when the token exchange fails", async () => {
+    const http = {
+      post: vi.fn().mockRejectedValue({
+        response: { status: 400, data: { error: "invalid_grant" } },
+      }),
+    } as any;
+    const oauth = new SpotifyOAuth({
+      clientId: CLIENT_ID,
+      redirectUri: REDIRECT_URI,
+      store: memStore(),
+      deps: { http },
+    });
+    const { state } = oauth.buildAuthorizeUrl();
+
+    // First attempt fails at the network/token step.
+    expect(await oauth.handleCallback("CODE", state)).toBe(false);
+    expect(http.post).toHaveBeenCalledTimes(1);
+
+    // Replaying the same state now fails the CSRF guard (verifier was deleted),
+    // WITHOUT hitting the token endpoint again.
+    expect(await oauth.handleCallback("CODE", state)).toBe(false);
+    expect(http.post).toHaveBeenCalledTimes(1);
+  });
+});
+
+describe("SpotifyOAuth.getAccessToken", () => {
+  it("returns the cached token without refreshing when still valid", async () => {
+    const http = { post: vi.fn() } as any;
+    const store = memStore({
+      accessToken: "cached",
+      refreshToken: "r1",
+      expiresAt: Date.now() + 60_000,
+      scope: "s",
+    });
+    const oauth = new SpotifyOAuth({ clientId: CLIENT_ID, store, deps: { http } });
+    expect(await oauth.getAccessToken()).toBe("cached");
+    expect(http.post).not.toHaveBeenCalled();
+  });
+
+  it("refreshes when expired and persists the ROTATED refresh token", async () => {
+    const store = memStore({
+      accessToken: "old",
+      refreshToken: "r1",
+      expiresAt: Date.now() - 1000,
+      scope: "s",
+    });
+    const http = {
+      post: vi.fn().mockResolvedValue({
+        data: { access_token: "a2", refresh_token: "r2", expires_in: 3600 },
+      }),
+    } as any;
+    const oauth = new SpotifyOAuth({ clientId: CLIENT_ID, store, deps: { http } });
+
+    expect(await oauth.getAccessToken()).toBe("a2");
+    const body = new URLSearchParams(http.post.mock.calls[0][1] as string);
+    expect(body.get("grant_type")).toBe("refresh_token");
+    expect(body.get("refresh_token")).toBe("r1");
+    expect(body.get("client_id")).toBe(CLIENT_ID);
+    expect(store.value?.refreshToken).toBe("r2"); // rotated + persisted
+    expect(store.value?.accessToken).toBe("a2");
+  });
+
+  it("keeps the old refresh token when the refresh response omits a new one", async () => {
+    const store = memStore({
+      accessToken: "old",
+      refreshToken: "r1",
+      expiresAt: Date.now() - 1000,
+      scope: "s",
+    });
+    const http = {
+      post: vi.fn().mockResolvedValue({ data: { access_token: "a2", expires_in: 3600 } }),
+    } as any;
+    const oauth = new SpotifyOAuth({ clientId: CLIENT_ID, store, deps: { http } });
+    expect(await oauth.getAccessToken()).toBe("a2");
+    expect(store.value?.refreshToken).toBe("r1");
+  });
+
+  it("clears the store and returns null on invalid_grant (expired refresh token)", async () => {
+    const store = memStore({
+      accessToken: "old",
+      refreshToken: "r1",
+      expiresAt: Date.now() - 1000,
+      scope: "s",
+    });
+    const http = {
+      post: vi.fn().mockRejectedValue({
+        response: { status: 400, data: { error: "invalid_grant" } },
+      }),
+    } as any;
+    const oauth = new SpotifyOAuth({ clientId: CLIENT_ID, store, deps: { http } });
+    expect(await oauth.getAccessToken()).toBeNull();
+    expect(store.value).toBeNull();
+    expect(oauth.isAuthorized()).toBe(false);
+  });
+
+  it("returns null when unauthorized (no stored refresh token)", async () => {
+    const http = { post: vi.fn() } as any;
+    const oauth = new SpotifyOAuth({
+      clientId: CLIENT_ID,
+      store: memStore(),
+      deps: { http },
+    });
+    expect(await oauth.getAccessToken()).toBeNull();
+    expect(oauth.isAuthorized()).toBe(false);
+    expect(http.post).not.toHaveBeenCalled();
+  });
+});
+
+// S4.3: refresh-token rotation makes two concurrent refreshes race — the second
+// would POST with a token the first already invalidated. Collapse them into one.
+describe("SpotifyOAuth.getAccessToken (in-flight refresh, S4.3)", () => {
+  it("collapses concurrent refreshes into a single token POST", async () => {
+    let t = 0;
+    const now = () => t;
+    const store = memStore({
+      accessToken: "old",
+      refreshToken: "r1",
+      expiresAt: 0, // now()=0 is not < 0 -> expired -> must refresh
+      scope: "s",
+    });
+    const d = deferred<any>();
+    const http = { post: vi.fn().mockReturnValue(d.promise) } as any;
+    const oauth = new SpotifyOAuth({
+      clientId: CLIENT_ID,
+      store,
+      deps: { http, now },
+    });
+
+    // Fire two calls while the POST is still pending.
+    const p1 = oauth.getAccessToken();
+    const p2 = oauth.getAccessToken();
+    expect(http.post).toHaveBeenCalledTimes(1); // collapsed to ONE POST
+
+    d.resolve({
+      data: { access_token: "a2", refresh_token: "r2", expires_in: 3600 },
+    });
+    expect(await p1).toBe("a2");
+    expect(await p2).toBe("a2");
+    expect(http.post).toHaveBeenCalledTimes(1);
+    expect(store.value?.refreshToken).toBe("r2"); // rotated once, not twice
+  });
+
+  it("clears the in-flight refresh after it settles, allowing a later refresh", async () => {
+    let t = 0;
+    const now = () => t;
+    const store = memStore({
+      accessToken: "old",
+      refreshToken: "r1",
+      expiresAt: 0,
+      scope: "s",
+    });
+    const http = {
+      post: vi
+        .fn()
+        .mockResolvedValueOnce({
+          data: { access_token: "a2", refresh_token: "r2", expires_in: 3600 },
+        })
+        .mockResolvedValueOnce({
+          data: { access_token: "a3", refresh_token: "r3", expires_in: 3600 },
+        }),
+    } as any;
+    const oauth = new SpotifyOAuth({
+      clientId: CLIENT_ID,
+      store,
+      deps: { http, now },
+    });
+
+    expect(await oauth.getAccessToken()).toBe("a2");
+    expect(http.post).toHaveBeenCalledTimes(1);
+
+    // toTokens now uses this.now(): saved expiresAt = 0 + 3600s - 30s skew.
+    // Still valid at t=0 -> cached, no new POST.
+    expect(await oauth.getAccessToken()).toBe("a2");
+    expect(http.post).toHaveBeenCalledTimes(1);
+
+    // Advance past the newly-saved expiry -> in-flight was cleared, so a fresh
+    // refresh fires (proves .finally() reset refreshInFlight).
+    t = 3600 * 1000;
+    expect(await oauth.getAccessToken()).toBe("a3");
+    expect(http.post).toHaveBeenCalledTimes(2);
+    expect(store.value?.refreshToken).toBe("r3");
+  });
+});
+
+// S4.3: bound the PKCE verifier map so abandoned logins can't accumulate.
+describe("SpotifyOAuth PKCE verifier TTL + cap (S4.3)", () => {
+  it("expires a pending verifier after the TTL (handleCallback returns false)", async () => {
+    let t = 0;
+    const now = () => t;
+    const http = { post: vi.fn() } as any;
+    const oauth = new SpotifyOAuth({
+      clientId: CLIENT_ID,
+      redirectUri: REDIRECT_URI,
+      store: memStore(),
+      deps: { http, now },
+    });
+    const { state } = oauth.buildAuthorizeUrl();
+
+    t = 10 * 60 * 1000 + 1; // VERIFIER_TTL_MS + 1
+    expect(await oauth.handleCallback("CODE", state)).toBe(false);
+    expect(http.post).not.toHaveBeenCalled(); // never reached the token step
+  });
+
+  it("caps the verifier map, evicting the oldest state (behavioral)", async () => {
+    let t = 0;
+    const now = () => t;
+    const http = {
+      post: vi.fn().mockResolvedValue({
+        data: { access_token: "a1", refresh_token: "r1", expires_in: 3600 },
+      }),
+    } as any;
+    const oauth = new SpotifyOAuth({
+      clientId: CLIENT_ID,
+      redirectUri: REDIRECT_URI,
+      store: memStore(),
+      deps: { http, now },
+    });
+
+    // First (oldest) state, then enough more to exceed VERIFIER_MAX (32).
+    const first = oauth.buildAuthorizeUrl().state;
+    let last = first;
+    for (let i = 0; i < 32; i++) last = oauth.buildAuthorizeUrl().state;
+
+    // The oldest was evicted -> unknown state -> CSRF guard, no token POST.
+    expect(await oauth.handleCallback("CODE", first)).toBe(false);
+    expect(http.post).not.toHaveBeenCalled();
+
+    // A still-pending (newest) state DOES resolve -> only the oldest was dropped.
+    expect(await oauth.handleCallback("CODE", last)).toBe(true);
+    expect(http.post).toHaveBeenCalledTimes(1);
+  });
+});
+
+// Whole-branch I2: a UI-entered Client ID (saved in Settings) must reach the
+// single live SpotifyOAuth WITHOUT a process restart. configure() re-arms the
+// runtime credentials; an empty clientId re-disables OAuth.
+describe("SpotifyOAuth.configure (runtime credentials, whole-branch I2)", () => {
+  it("applies a UI-entered clientId + redirectUri so OAuth arms without a restart", () => {
+    // Fresh install: boot-time config had no clientId, so OAuth is disabled.
+    const store = memStore({
+      accessToken: "a",
+      refreshToken: "r",
+      expiresAt: Date.now() + 60_000,
+      scope: "s",
+    });
+    const oauth = new SpotifyOAuth({ clientId: "", store });
+    expect(oauth.isAuthorized()).toBe(false);
+    expect(() => oauth.buildAuthorizeUrl()).toThrow(/Client ID/i);
+
+    // Operator enters creds in Settings -> POST /settings calls configure().
+    const REDIRECT = "http://127.0.0.1:3000/api/spotify/callback";
+    oauth.configure("cid", REDIRECT);
+    expect(oauth.getClientId()).toBe("cid");
+    expect(oauth.getRedirectUri()).toBe(REDIRECT);
+    // Now authorize + isAuthorized work against the newly-supplied app.
+    expect(oauth.isAuthorized()).toBe(true);
+    const { url } = oauth.buildAuthorizeUrl();
+    const p = new URL(url).searchParams;
+    expect(p.get("client_id")).toBe("cid");
+    expect(p.get("redirect_uri")).toBe(REDIRECT);
+  });
+
+  it("trims the clientId and re-disables OAuth when cleared", () => {
+    const oauth = new SpotifyOAuth({
+      clientId: "old",
+      redirectUri: "http://old",
+      store: memStore(),
+    });
+    oauth.configure("  cid  ", "http://127.0.0.1:3000/api/spotify/callback");
+    expect(oauth.getClientId()).toBe("cid"); // trimmed
+
+    // Empty clientId disables OAuth again (gate on buildAuthorizeUrl/isAuthorized).
+    oauth.configure("");
+    expect(oauth.getClientId()).toBe("");
+    expect(oauth.getRedirectUri()).toBe("");
+    expect(oauth.isAuthorized()).toBe(false);
+    expect(() => oauth.buildAuthorizeUrl()).toThrow(/Client ID/i);
+  });
+});
+
+describe("createFileOAuthTokenStore", () => {
+  it("round-trips save/load and clear() removes it", () => {
+    const dir = mkdtempSync(join(tmpdir(), "sp-oauth-"));
+    const file = join(dir, "nested", "tokens.json");
+    try {
+      const store = createFileOAuthTokenStore(file);
+      expect(store.load()).toBeNull(); // missing file
+      const t: OAuthTokens = {
+        accessToken: "a",
+        refreshToken: "r",
+        expiresAt: 123,
+        scope: "s",
+      };
+      store.save(t);
+      expect(store.load()).toEqual(t);
+      store.clear();
+      expect(store.load()).toBeNull();
+    } finally {
+      rmSync(dir, { recursive: true, force: true });
+    }
+  });
+});
+
+// R3-5: the token store save() must be atomic (same-dir temp file + rename), so
+// a crash / power loss / ENOSPC while persisting a ROTATED refresh token (Spotify
+// invalidates the OLD one the instant it responds — the new one lives only in
+// memory until this write lands) can never truncate the file and silently
+// de-authenticate the operator. Mirrors the hardened config.ts saveConfig.
+describe("createFileOAuthTokenStore atomic write (R3-5)", () => {
+  const dirs: string[] = [];
+  function makeTmpDir(): string {
+    const dir = mkdtempSync(join(tmpdir(), "sp-oauth-atomic-"));
+    dirs.push(dir);
+    return dir;
+  }
+  beforeEach(() => {
+    vi.clearAllMocks(); // reset call history, keep the call-through implementations
+  });
+  afterEach(() => {
+    for (const d of dirs) rmSync(d, { recursive: true, force: true });
+    dirs.length = 0;
+  });
+
+  const TOK: OAuthTokens = {
+    accessToken: "a",
+    refreshToken: "r",
+    expiresAt: 123,
+    scope: "s",
+  };
+
+  it("round-trips save/load and leaves NO .tmp file behind", () => {
+    const dir = makeTmpDir();
+    const file = join(dir, "tokens.json");
+    const store = createFileOAuthTokenStore(file);
+
+    store.save(TOK);
+
+    expect(store.load()).toEqual(TOK);
+    // No temp remnants in the target directory.
+    expect(readdirSync(dir).filter((f) => f.includes(".tmp"))).toEqual([]);
+  });
+
+  it("writes via a same-dir temp file then renameSync onto the final path", () => {
+    const dir = makeTmpDir();
+    const file = join(dir, "tokens.json");
+
+    createFileOAuthTokenStore(file).save(TOK);
+
+    expect(vi.mocked(renameSync)).toHaveBeenCalled();
+    const [from, to] = vi.mocked(renameSync).mock.calls[0] as [string, string];
+    expect(to).toBe(file); // renamed ONTO the real path
+    expect(String(from)).not.toBe(file); // ...from a distinct temp file
+    expect(join(String(from), "..")).toBe(join(file, "..")); // ...in the SAME dir
+  });
+
+  it("persists the token file with 0600 permissions (POSIX)", () => {
+    if (process.platform === "win32") return; // mode bits aren't meaningful on Windows
+    const dir = makeTmpDir();
+    const file = join(dir, "tokens.json");
+    createFileOAuthTokenStore(file).save(TOK);
+    expect(statSync(file).mode & 0o777).toBe(0o600);
+  });
+
+  it("does NOT truncate/corrupt a pre-existing valid token file when the write fails mid-way", () => {
+    const dir = makeTmpDir();
+    const file = join(dir, "tokens.json");
+    const store = createFileOAuthTokenStore(file);
+
+    // A valid, previously-persisted token file (the live refresh token on disk).
+    store.save(TOK);
+    const before = readFileSync(file, "utf-8");
+
+    // Simulate a crash / ENOSPC at the atomic-replace step while persisting a
+    // ROTATED refresh token.
+    const rotated: OAuthTokens = { ...TOK, accessToken: "a2", refreshToken: "r2" };
+    vi.mocked(renameSync).mockImplementationOnce(() => {
+      throw new Error("rename boom");
+    });
+
+    expect(() => store.save(rotated)).toThrow(/rename boom/);
+
+    // The original file is untouched: present, byte-identical, still parseable.
+    expect(readFileSync(file, "utf-8")).toBe(before);
+    expect(store.load()).toEqual(TOK);
+    // ...and the failed write left no temp file lying around.
+    expect(readdirSync(dir).filter((f) => f.includes(".tmp"))).toEqual([]);
+  });
+});

src/music/spotify/spotify-oauth.ts

@@ -0,0 +1,298 @@
+import axios, { type AxiosInstance } from "axios";
+import { createHash, randomBytes } from "node:crypto";
+import {
+  existsSync,
+  mkdirSync,
+  readFileSync,
+  renameSync,
+  rmSync,
+  writeFileSync,
+} from "node:fs";
+import { dirname } from "node:path";
+
+/**
+ * Player-control scopes requested for the USER token: streaming (drives
+ * librespot as a Connect device) + read/modify playback + currently-playing +
+ * private-playlist reads.
+ */
+export const SPOTIFY_CONTROL_SCOPES =
+  "streaming user-read-playback-state user-modify-playback-state user-read-currently-playing playlist-read-private";
+
+const ACCOUNTS_BASE = "https://accounts.spotify.com";
+// Hand a token back only if it survives ~30s, matching webapi.ts's skew.
+const EXPIRY_SKEW_MS = 30_000;
+// RFC 7636 §4.1 unreserved set: [A-Za-z0-9-._~].
+const PKCE_CHARS =
+  "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~";
+const FORM_HEADERS = { "Content-Type": "application/x-www-form-urlencoded" };
+
+export interface OAuthTokens {
+  accessToken: string;
+  refreshToken: string;
+  expiresAt: number;
+  scope: string;
+}
+
+export interface OAuthTokenStore {
+  load(): OAuthTokens | null;
+  save(t: OAuthTokens): void;
+  clear(): void;
+}
+
+export interface SpotifyOAuthOptions {
+  /**
+   * Correction C3.2: the caller's OWN Spotify Developer app client_id. There is
+   * no librespot-public-client fallback — an empty clientId disables OAuth.
+   */
+  clientId?: string;
+  /**
+   * Loopback redirect registered on the caller's Spotify app, supplied by the
+   * bot's web layer (e.g. its `/api/spotify/callback`). Must exactly match the
+   * value used at both the authorize and token steps.
+   */
+  redirectUri?: string;
+  store: OAuthTokenStore;
+  deps?: { http?: AxiosInstance; now?: () => number };
+}
+
+/** 64 random chars from the PKCE unreserved set (43-128 allowed by the spec). */
+export function generateCodeVerifier(): string {
+  const bytes = randomBytes(64);
+  let out = "";
+  for (let i = 0; i < 64; i++) out += PKCE_CHARS[bytes[i] % PKCE_CHARS.length];
+  return out;
+}
+
+/** base64url(SHA256(verifier)) with no padding — the S256 code challenge. */
+export function codeChallengeS256(verifier: string): string {
+  return createHash("sha256").update(verifier).digest("base64url");
+}
+
+/** Persist OAuth tokens as a 0600 JSON file (used by the controller). */
+export function createFileOAuthTokenStore(filePath: string): OAuthTokenStore {
+  return {
+    load() {
+      try {
+        if (!existsSync(filePath)) return null;
+        const parsed = JSON.parse(readFileSync(filePath, "utf8"));
+        return parsed?.refreshToken ? (parsed as OAuthTokens) : null;
+      } catch {
+        return null; // missing/corrupt -> treat as unauthorized
+      }
+    },
+    save(t: OAuthTokens) {
+      mkdirSync(dirname(filePath), { recursive: true });
+      // Atomic write: serialize to a sibling temp file in the SAME directory,
+      // then rename it onto the final path. rename is an atomic replace on POSIX
+      // and modern Windows, so a crash / power loss / ENOSPC mid-write can never
+      // leave the token file truncated — a reader always sees either the previous
+      // file or the fully-written new one, never a partial. This matters because
+      // refresh() persists a ROTATED refresh token here: Spotify invalidates the
+      // OLD one the instant it responds, so a torn write would silently
+      // de-authenticate the operator (next load() JSON.parse-fails -> null ->
+      // full PKCE re-login). Mirrors config.ts saveConfig. The temp lives in the
+      // same dir so the rename stays on one filesystem; pid + timestamp keep
+      // concurrent writers from colliding on the temp name. 0600 is preserved.
+      const tmp = `${filePath}.${process.pid}.${Date.now()}.tmp`;
+      try {
+        writeFileSync(tmp, JSON.stringify(t, null, 2), { mode: 0o600 });
+        renameSync(tmp, filePath);
+      } catch (err) {
+        // Never leave a partial temp file behind on failure.
+        try {
+          rmSync(tmp, { force: true });
+        } catch {
+          /* best-effort cleanup */
+        }
+        throw err;
+      }
+    },
+    clear() {
+      try {
+        rmSync(filePath, { force: true });
+      } catch {
+        /* already gone */
+      }
+    },
+  };
+}
+
+/**
+ * Authorization Code + PKCE flow for the USER player-control token. Public
+ * client (no secret).
+ *
+ * Correction C3.2: this REQUIRES the operator's own registered Spotify app —
+ * there is NO reuse of librespot's first-party keymaster client / fixed
+ * :5588 redirect. Without a clientId, `isAuthorized()` is false and
+ * `buildAuthorizeUrl()` throws.
+ *
+ * Refresh rotates the refresh token, so the newest is always persisted;
+ * invalid_grant clears the store (re-login required). Access/refresh tokens
+ * are never logged.
+ */
+export class SpotifyOAuth {
+  private clientId: string;
+  private redirectUri: string;
+  private store: OAuthTokenStore;
+  private http: AxiosInstance;
+  // Injectable clock (tests drive a mutable now); defaults to Date.now.
+  private now: () => number;
+  // Pending PKCE verifiers keyed by state, awaiting the loopback redirect back.
+  private pendingVerifiers = new Map<
+    string,
+    { verifier: string; expiresAt: number }
+  >();
+  // A verifier is abandoned if the redirect never returns; drop it after TTL and
+  // cap the map so parallel logins can't grow it without bound.
+  private static readonly VERIFIER_TTL_MS = 10 * 60 * 1000;
+  private static readonly VERIFIER_MAX = 32;
+  // Collapse concurrent refreshes into one POST (rotation invalidates the token
+  // a second in-flight refresh would send); cleared in .finally().
+  private refreshInFlight: Promise<string | null> | null = null;
+
+  constructor(o: SpotifyOAuthOptions) {
+    this.clientId = o.clientId ?? "";
+    this.redirectUri = o.redirectUri ?? "";
+    this.store = o.store;
+    this.http =
+      o.deps?.http ?? axios.create({ baseURL: ACCOUNTS_BASE, timeout: 15_000 });
+    this.now = o.deps?.now ?? (() => Date.now());
+  }
+
+  private evictStaleVerifiers(): void {
+    const t = this.now();
+    for (const [state, e] of this.pendingVerifiers) {
+      if (e.expiresAt < t) this.pendingVerifiers.delete(state);
+    }
+    // Bound memory even if all are unexpired: drop oldest (insertion order).
+    while (this.pendingVerifiers.size >= SpotifyOAuth.VERIFIER_MAX) {
+      const oldest = this.pendingVerifiers.keys().next().value;
+      if (oldest === undefined) break;
+      this.pendingVerifiers.delete(oldest);
+    }
+  }
+
+  /** Update the operator's app credentials at runtime (from Settings save) so
+   *  a UI-entered Client ID takes effect without a process restart. Empty
+   *  clientId disables OAuth (isAuthorized()/buildAuthorizeUrl() gate on it). */
+  configure(clientId?: string, redirectUri?: string): void {
+    this.clientId = clientId?.trim() || "";
+    this.redirectUri = redirectUri || "";
+  }
+
+  getClientId(): string {
+    return this.clientId;
+  }
+
+  getRedirectUri(): string {
+    return this.redirectUri;
+  }
+
+  isAuthorized(): boolean {
+    // C3.2: no client_id means we could never refresh, so treat as unauthorized.
+    return !!this.clientId && !!this.store.load()?.refreshToken;
+  }
+
+  buildAuthorizeUrl(): { url: string; state: string } {
+    if (!this.clientId) {
+      // C3.2: cannot start OAuth against nobody's app.
+      throw new Error("Set your Spotify Client ID in settings first");
+    }
+    const state = randomBytes(16).toString("hex");
+    const verifier = generateCodeVerifier();
+    this.evictStaleVerifiers();
+    this.pendingVerifiers.set(state, {
+      verifier,
+      expiresAt: this.now() + SpotifyOAuth.VERIFIER_TTL_MS,
+    });
+    const params = new URLSearchParams({
+      client_id: this.clientId,
+      response_type: "code",
+      redirect_uri: this.redirectUri,
+      code_challenge: codeChallengeS256(verifier),
+      code_challenge_method: "S256",
+      scope: SPOTIFY_CONTROL_SCOPES,
+      state,
+    });
+    return { url: `${ACCOUNTS_BASE}/authorize?${params.toString()}`, state };
+  }
+
+  async handleCallback(code: string, state: string): Promise<boolean> {
+    const entry = this.pendingVerifiers.get(state);
+    if (!entry || entry.expiresAt < this.now()) {
+      // unknown/expired state -> CSRF guard (drop any stale entry too)
+      this.pendingVerifiers.delete(state);
+      return false;
+    }
+    const verifier = entry.verifier;
+    // C3.7: drop the state->verifier entry on EVERY terminal path (success,
+    // rejected token exchange, or throw) so a failed login can't leak/replay it.
+    try {
+      const body = new URLSearchParams({
+        grant_type: "authorization_code",
+        code,
+        redirect_uri: this.redirectUri,
+        client_id: this.clientId,
+        code_verifier: verifier,
+      });
+      const { data } = await this.http.post("/api/token", body.toString(), {
+        headers: FORM_HEADERS,
+      });
+      if (!data?.access_token || !data?.refresh_token) return false;
+      this.store.save(this.toTokens(data, data.refresh_token, data.scope));
+      return true;
+    } catch {
+      return false;
+    } finally {
+      this.pendingVerifiers.delete(state);
+    }
+  }
+
+  async getAccessToken(): Promise<string | null> {
+    if (!this.clientId) return null; // C3.2: no app => nothing to mint against
+    const tokens = this.store.load();
+    if (!tokens?.refreshToken) return null; // unauthorized
+    if (tokens.accessToken && this.now() < tokens.expiresAt) {
+      return tokens.accessToken;
+    }
+    // Collapse concurrent refreshes: rotation makes a second in-flight refresh
+    // use a refresh token the first one already invalidated.
+    if (this.refreshInFlight) return this.refreshInFlight;
+    this.refreshInFlight = this.refresh(tokens).finally(() => {
+      this.refreshInFlight = null;
+    });
+    return this.refreshInFlight;
+  }
+
+  private async refresh(current: OAuthTokens): Promise<string | null> {
+    const body = new URLSearchParams({
+      grant_type: "refresh_token",
+      refresh_token: current.refreshToken,
+      client_id: this.clientId,
+    });
+    try {
+      const { data } = await this.http.post("/api/token", body.toString(), {
+        headers: FORM_HEADERS,
+      });
+      if (!data?.access_token) return null;
+      // PKCE rotates the refresh token; fall back to the current one if omitted.
+      const rotated = data.refresh_token || current.refreshToken;
+      const saved = this.toTokens(data, rotated, data.scope ?? current.scope);
+      this.store.save(saved);
+      return saved.accessToken;
+    } catch (err: any) {
+      // invalid_grant => refresh token revoked/expired: discard, force re-login.
+      if (err?.response?.data?.error === "invalid_grant") this.store.clear();
+      return null;
+    }
+  }
+
+  private toTokens(data: any, refreshToken: string, scope: string): OAuthTokens {
+    return {
+      accessToken: data.access_token,
+      refreshToken,
+      expiresAt: this.now() + (data.expires_in ?? 3600) * 1000 - EXPIRY_SKEW_MS,
+      scope: scope ?? SPOTIFY_CONTROL_SCOPES,
+    };
+  }
+}

src/music/spotify/webapi.test.ts

@@ -0,0 +1,577 @@
+import { describe, it, expect, vi } from "vitest";
+import {
+  mapSpotifyTrack,
+  mapSpotifyTracks,
+  mapSpotifyAlbum,
+  mapSpotifyPlaylist,
+  isSpotifyUri,
+  SpotifyWebApi,
+} from "./webapi.js";
+
+describe("mapSpotifyTrack", () => {
+  // Shape trimmed from GET /v1/search?type=track.
+  const raw = {
+    id: "4iV5W9uYEdYUVa79Axb7Rh",
+    name: "Bohemian Rhapsody",
+    artists: [{ name: "Queen" }],
+    album: { name: "A Night at the Opera", images: [{ url: "https://i.scdn.co/x.jpg" }] },
+    duration_ms: 354320,
+  };
+
+  it("maps a track to a Song with platform 'spotify' and seconds duration", () => {
+    const s = mapSpotifyTrack(raw);
+    expect(s.platform).toBe("spotify");
+    expect(s.id).toBe("4iV5W9uYEdYUVa79Axb7Rh");
+    expect(s.name).toBe("Bohemian Rhapsody");
+    expect(s.artist).toBe("Queen");
+    expect(s.album).toBe("A Night at the Opera");
+    expect(s.duration).toBe(354); // 354320ms → 354s
+    expect(s.coverUrl).toBe("https://i.scdn.co/x.jpg");
+  });
+
+  it("joins multiple artists with ', '", () => {
+    const s = mapSpotifyTrack({ ...raw, artists: [{ name: "A" }, { name: "B" }] });
+    expect(s.artist).toBe("A, B");
+  });
+
+  it("tolerates missing fields", () => {
+    const s = mapSpotifyTrack({});
+    expect(s.id).toBe("");
+    expect(s.name).toBe("Unknown");
+    expect(s.artist).toBe("");
+    expect(s.duration).toBe(0);
+    expect(s.coverUrl).toBe("");
+    expect(s.platform).toBe("spotify");
+  });
+
+  it("mapSpotifyTracks returns [] for non-array input", () => {
+    expect(mapSpotifyTracks(undefined as any)).toEqual([]);
+  });
+});
+
+describe("mapSpotifyAlbum", () => {
+  it("maps an album with total_tracks → songCount", () => {
+    const a = mapSpotifyAlbum({
+      id: "1abc",
+      name: "A Night at the Opera",
+      artists: [{ name: "Queen" }],
+      images: [{ url: "https://i.scdn.co/a.jpg" }],
+      total_tracks: 12,
+    });
+    expect(a).toEqual({
+      id: "1abc",
+      name: "A Night at the Opera",
+      artist: "Queen",
+      coverUrl: "https://i.scdn.co/a.jpg",
+      songCount: 12,
+      platform: "spotify",
+    });
+  });
+});
+
+describe("mapSpotifyPlaylist", () => {
+  it("maps a playlist with tracks.total → songCount", () => {
+    const p = mapSpotifyPlaylist({
+      id: "37i9",
+      name: "Today's Top Hits",
+      images: [{ url: "https://i.scdn.co/p.jpg" }],
+      tracks: { total: 50 },
+    });
+    expect(p).toEqual({
+      id: "37i9",
+      name: "Today's Top Hits",
+      coverUrl: "https://i.scdn.co/p.jpg",
+      songCount: 50,
+      platform: "spotify",
+    });
+  });
+});
+
+describe("isSpotifyUri", () => {
+  it("recognizes the sentinel URI", () => {
+    expect(isSpotifyUri("spotify:track:4iV5W9uYEdYUVa79Axb7Rh")).toBe(true);
+    expect(isSpotifyUri("https://music.126.net/x.mp3")).toBe(false);
+    expect(isSpotifyUri("")).toBe(false);
+  });
+});
+
+describe("SpotifyWebApi rate-limit handling", () => {
+  it("retries once on 429 (honoring Retry-After) then returns data", async () => {
+    const auth = {
+      post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+    } as any;
+    let call = 0;
+    const http = {
+      get: vi.fn().mockImplementation(() => {
+        call += 1;
+        if (call === 1) {
+          return Promise.reject({ response: { status: 429, headers: { "retry-after": "0" } } });
+        }
+        return Promise.resolve({
+          data: { tracks: { items: [{ id: "t1", name: "n", artists: [], duration_ms: 1000 }] } },
+        });
+      }),
+    } as any;
+    const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+    const out = await api.search("queen");
+    expect(http.get).toHaveBeenCalledTimes(2); // one 429, one success
+    expect(out.songs[0].id).toBe("t1");
+  });
+
+  // I5: the retry is BOUNDED — get() passes `false` on the recursive call so a
+  // second 429 is NOT retried. Without that bound arg this recurses forever;
+  // this test must FAIL (time out) if the `false` in `this.get(path, params, false)`
+  // is removed. retry-after "0" keeps the single permitted wait instant.
+  it("gives up after exactly ONE 429 retry when every call 429s (bounded, no infinite loop)", async () => {
+    const auth = {
+      post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+    } as any;
+    const http = {
+      get: vi.fn().mockRejectedValue({
+        response: { status: 429, headers: { "retry-after": "0" } },
+      }),
+    } as any;
+    const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+    const out = await api.search("queen");
+    // Exactly two attempts: the original + one bounded retry, then it stops.
+    expect(http.get).toHaveBeenCalledTimes(2);
+    // Giving up returns null from get() → search yields an empty (non-throwing) result.
+    expect(out).toEqual({ songs: [], playlists: [], albums: [] });
+  });
+
+  // I5: the advised wait is capped by Math.min(retryAfter, 10). A large Retry-After
+  // (999s) must still wait only 10s, proving the cap. Fake timers keep it instant
+  // while letting us assert the retry fires at 10s, not before.
+  it("caps the Retry-After wait at 10s (Math.min(retryAfter, 10))", async () => {
+    vi.useFakeTimers();
+    try {
+      const auth = {
+        post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+      } as any;
+      let call = 0;
+      const http = {
+        get: vi.fn().mockImplementation(() => {
+          call += 1;
+          if (call === 1) {
+            return Promise.reject({ response: { status: 429, headers: { "retry-after": "999" } } });
+          }
+          return Promise.resolve({
+            data: { tracks: { items: [{ id: "t1", name: "n", artists: [], duration_ms: 1000 }] } },
+          });
+        }),
+      } as any;
+      const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+      const p = api.search("queen");
+
+      // Let the token fetch + first (429) call settle and schedule the wait.
+      await vi.advanceTimersByTimeAsync(9_000); // 9s < cap → retry has NOT fired yet
+      expect(http.get).toHaveBeenCalledTimes(1);
+
+      await vi.advanceTimersByTimeAsync(1_000); // now 10s total → cap reached, retry fires
+      const out = await p;
+      expect(http.get).toHaveBeenCalledTimes(2);
+      expect(out.songs[0].id).toBe("t1");
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+
+  // Corner-case: a non-numeric Retry-After (HTTP-date) must NOT coerce to NaN and
+  // fire the retry at 0ms. `Number("Wed, 21 Oct 2025 07:28:00 GMT")` is NaN, so the
+  // pre-fix `Math.min(NaN,10)*1000` schedules an immediate (or never-firing) retry
+  // that ignores the advised backoff. Post-fix falls back to a finite 1s wait: the
+  // retry stays scheduled at exactly the fallback, still bounded to ONE retry.
+  it("falls back to a finite 1s wait when Retry-After is an HTTP-date (not NaN/immediate)", async () => {
+    vi.useFakeTimers();
+    try {
+      const auth = {
+        post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+      } as any;
+      let call = 0;
+      const http = {
+        get: vi.fn().mockImplementation(() => {
+          call += 1;
+          if (call === 1) {
+            return Promise.reject({
+              response: {
+                status: 429,
+                headers: { "retry-after": "Wed, 21 Oct 2025 07:28:00 GMT" },
+              },
+            });
+          }
+          return Promise.resolve({
+            data: { tracks: { items: [{ id: "t1", name: "n", artists: [], duration_ms: 1000 }] } },
+          });
+        }),
+      } as any;
+      const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+      const p = api.search("queen");
+
+      // Let the token fetch + first (429) call settle and schedule the wait.
+      await vi.advanceTimersByTimeAsync(999); // < 1s fallback → retry has NOT fired yet
+      expect(http.get).toHaveBeenCalledTimes(1);
+
+      await vi.advanceTimersByTimeAsync(1); // now 1s total → finite fallback reached, retry fires
+      const out = await p;
+      expect(http.get).toHaveBeenCalledTimes(2); // exactly one bounded retry
+      expect(out.songs[0].id).toBe("t1");
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+
+  // Corner-case sibling: an empty Retry-After coerces to 0 (`Number("")` === 0), so
+  // pre-fix `Math.min(0,10)*1000` fires the retry immediately at 0ms. Post-fix guards
+  // `raw > 0`, so it falls back to the same finite 1s wait rather than firing at 0.
+  it("falls back to a finite 1s wait when Retry-After is empty (not 0/immediate)", async () => {
+    vi.useFakeTimers();
+    try {
+      const auth = {
+        post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+      } as any;
+      let call = 0;
+      const http = {
+        get: vi.fn().mockImplementation(() => {
+          call += 1;
+          if (call === 1) {
+            return Promise.reject({ response: { status: 429, headers: { "retry-after": "" } } });
+          }
+          return Promise.resolve({
+            data: { tracks: { items: [{ id: "t1", name: "n", artists: [], duration_ms: 1000 }] } },
+          });
+        }),
+      } as any;
+      const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+      const p = api.search("queen");
+
+      await vi.advanceTimersByTimeAsync(999); // < 1s fallback → retry must NOT have fired at 0ms
+      expect(http.get).toHaveBeenCalledTimes(1);
+
+      await vi.advanceTimersByTimeAsync(1); // 1s total → fallback reached, retry fires
+      const out = await p;
+      expect(http.get).toHaveBeenCalledTimes(2);
+      expect(out.songs[0].id).toBe("t1");
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+
+  // Regression guard: a NORMAL numeric Retry-After ("3") is finite/positive, so the
+  // guard is transparent — the advised ~3s wait (below the 10s cap) is honored intact.
+  it("still honors a normal numeric Retry-After (~3s, below the 10s cap)", async () => {
+    vi.useFakeTimers();
+    try {
+      const auth = {
+        post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+      } as any;
+      let call = 0;
+      const http = {
+        get: vi.fn().mockImplementation(() => {
+          call += 1;
+          if (call === 1) {
+            return Promise.reject({ response: { status: 429, headers: { "retry-after": "3" } } });
+          }
+          return Promise.resolve({
+            data: { tracks: { items: [{ id: "t1", name: "n", artists: [], duration_ms: 1000 }] } },
+          });
+        }),
+      } as any;
+      const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+      const p = api.search("queen");
+
+      await vi.advanceTimersByTimeAsync(2_999); // < 3s advised → retry has NOT fired yet
+      expect(http.get).toHaveBeenCalledTimes(1);
+
+      await vi.advanceTimersByTimeAsync(1); // 3s total → advised wait reached, retry fires
+      const out = await p;
+      expect(http.get).toHaveBeenCalledTimes(2);
+      expect(out.songs[0].id).toBe("t1");
+    } finally {
+      vi.useRealTimers();
+    }
+  });
+
+  it("returns empty results when unconfigured (no creds → no token)", async () => {
+    const api = new SpotifyWebApi(() => ({ clientId: "", clientSecret: "" }));
+    expect(await api.search("queen")).toEqual({ songs: [], playlists: [], albums: [] });
+  });
+});
+
+// m4: the catalog fetch mappers (getTrack / getAlbumTracks / getPlaylistTracks)
+// were untested. They shape raw Spotify payloads into Songs, inject album cover
+// context, and drop malformed playlist rows.
+describe("SpotifyWebApi catalog mappers", () => {
+  /** Builds an api whose single http.get resolves the supplied payload. */
+  function makeApi(payload: unknown) {
+    const auth = {
+      post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+    } as any;
+    const http = { get: vi.fn().mockResolvedValue({ data: payload }) } as any;
+    const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+    return { api, http };
+  }
+
+  describe("getTrack", () => {
+    it("maps a single track payload to a Song", async () => {
+      const { api } = makeApi({
+        id: "trk1",
+        name: "Song One",
+        artists: [{ name: "Alice" }, { name: "Bob" }],
+        album: { name: "Album X", images: [{ url: "https://i.scdn.co/t.jpg" }] },
+        duration_ms: 210000,
+      });
+      const s = await api.getTrack("trk1");
+      expect(s).toEqual({
+        id: "trk1",
+        name: "Song One",
+        artist: "Alice, Bob",
+        album: "Album X",
+        duration: 210,
+        coverUrl: "https://i.scdn.co/t.jpg",
+        platform: "spotify",
+      });
+    });
+
+    it("returns null when the track fetch yields no data", async () => {
+      const auth = {
+        post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+      } as any;
+      const http = { get: vi.fn().mockResolvedValue({ data: null }) } as any;
+      const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+      expect(await api.getTrack("nope")).toBeNull();
+    });
+  });
+
+  describe("getAlbumTracks", () => {
+    it("injects the album name + cover into every returned track", async () => {
+      // Album-track objects omit their own album block; the album cover/name must
+      // be back-filled from the album payload.
+      const { api } = makeApi({
+        name: "A Night at the Opera",
+        images: [{ url: "https://i.scdn.co/album.jpg" }],
+        tracks: {
+          items: [
+            { id: "a1", name: "Death on Two Legs", artists: [{ name: "Queen" }], duration_ms: 223000 },
+            { id: "a2", name: "Lazing on a Sunday", artists: [{ name: "Queen" }], duration_ms: 68000 },
+          ],
+        },
+      });
+      const out = await api.getAlbumTracks("alb1");
+      expect(out).toHaveLength(2);
+      for (const t of out) {
+        expect(t.album).toBe("A Night at the Opera");
+        expect(t.coverUrl).toBe("https://i.scdn.co/album.jpg");
+        expect(t.platform).toBe("spotify");
+      }
+      expect(out[0].id).toBe("a1");
+      expect(out[0].name).toBe("Death on Two Legs");
+      expect(out[1].id).toBe("a2");
+    });
+
+    it("drops null track entries and returns [] when tracks.items is absent", async () => {
+      const { api: withNull } = makeApi({
+        name: "Alb",
+        images: [{ url: "https://i.scdn.co/c.jpg" }],
+        tracks: { items: [null, { id: "ok", name: "Keep", artists: [], duration_ms: 1000 }] },
+      });
+      const out = await withNull.getAlbumTracks("alb1");
+      expect(out).toHaveLength(1);
+      expect(out[0].id).toBe("ok");
+      expect(out[0].coverUrl).toBe("https://i.scdn.co/c.jpg");
+
+      const { api: noItems } = makeApi({ name: "Alb", images: [], tracks: {} });
+      expect(await noItems.getAlbumTracks("alb1")).toEqual([]);
+    });
+  });
+
+  describe("getPlaylistTracks", () => {
+    it("filters null items, {track:null}, and id-less tracks (never emits an id:'' Song)", async () => {
+      const { api } = makeApi({
+        items: [
+          null,
+          { track: null },
+          { track: { name: "No Id Here", artists: [], duration_ms: 1000 } }, // track present but no id
+          { track: { id: "p1", name: "Real Song", artists: [{ name: "X" }], duration_ms: 1000 } },
+        ],
+      });
+      const out = await api.getPlaylistTracks("pl1");
+      expect(out).toHaveLength(1);
+      expect(out[0].id).toBe("p1");
+      expect(out[0].name).toBe("Real Song");
+      // Guard the specific defect: no malformed empty-id Song leaks through.
+      expect(out.every((s) => s.id !== "")).toBe(true);
+    });
+
+    it("returns [] when items is absent", async () => {
+      const { api } = makeApi({});
+      expect(await api.getPlaylistTracks("pl1")).toEqual([]);
+    });
+  });
+});
+
+// R2-3: getPlaylistTracks must paginate (follow data.next) rather than silently
+// truncating to the first 100 tracks, and must stop at a bounded cap so a
+// pathological 10k-track playlist can't fan out into dozens of API calls.
+describe("getPlaylistTracks pagination (R2-3)", () => {
+  const trackItem = (i: number) => ({
+    track: { id: `p${i}`, name: `Song ${i}`, artists: [{ name: "X" }], duration_ms: 1000 },
+  });
+
+  it("follows data.next across pages, returning all tracks in order with nulls filtered", async () => {
+    const auth = {
+      post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+    } as any;
+    const page1 = {
+      items: Array.from({ length: 100 }, (_, i) => trackItem(i)),
+      next: "https://api.spotify.com/v1/playlists/pl1/tracks?offset=100&limit=100",
+    };
+    // Nulls / {track:null} / id-less rows on page 2 prove cross-page filtering.
+    const page2 = {
+      items: [null, { track: null }, { track: { name: "NoId", artists: [], duration_ms: 1 } }, trackItem(100), trackItem(101)],
+      next: null,
+    };
+    const http = {
+      get: vi.fn().mockResolvedValueOnce({ data: page1 }).mockResolvedValueOnce({ data: page2 }),
+    } as any;
+    const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+    const out = await api.getPlaylistTracks("pl1");
+
+    expect(http.get).toHaveBeenCalledTimes(2);
+    expect(out).toHaveLength(102); // 100 (page 1) + 2 real (page 2, three junk rows dropped)
+    expect(out[0].id).toBe("p0");
+    expect(out[99].id).toBe("p99");
+    expect(out[100].id).toBe("p100"); // page 2 appended in order
+    expect(out[101].id).toBe("p101");
+    expect(out.every((s) => s.id !== "")).toBe(true);
+  });
+
+  it("stops at the bounded cap when pages never end (call count bounded)", async () => {
+    const auth = {
+      post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+    } as any;
+    // Every page is full (100) and always advertises a further next page.
+    const http = {
+      get: vi.fn().mockImplementation((_path: string, cfg: any) => {
+        const offset = Number(cfg?.params?.offset ?? 0);
+        return Promise.resolve({
+          data: {
+            items: Array.from({ length: 100 }, (_, i) => trackItem(offset + i)),
+            next: `https://api.spotify.com/v1/playlists/pl1/tracks?offset=${offset + 100}`,
+          },
+        });
+      }),
+    } as any;
+    const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+    const out = await api.getPlaylistTracks("pl1");
+
+    expect(out.length).toBeLessThanOrEqual(500); // never exceeds the cap
+    expect(out).toHaveLength(500); // and reaches it exactly
+    expect(http.get.mock.calls.length).toBeLessThanOrEqual(5); // 500 cap / 100 per page
+  });
+});
+
+// R2-6: getAlbumTracks must page beyond the 50-track embedded cap via the
+// dedicated /albums/{id}/tracks endpoint, still injecting album name + cover.
+describe("getAlbumTracks pagination (R2-6)", () => {
+  const albTrack = (i: number) => ({ id: `a${i}`, name: `T${i}`, artists: [{ name: "Queen" }], duration_ms: 1000 });
+
+  it("pages beyond the embedded 50-track cap, injecting album name/cover", async () => {
+    const auth = {
+      post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+    } as any;
+    const albumPayload = {
+      name: "Big Compilation",
+      images: [{ url: "https://i.scdn.co/big.jpg" }],
+      tracks: {
+        items: Array.from({ length: 50 }, (_, i) => albTrack(i)),
+        next: "https://api.spotify.com/v1/albums/alb1/tracks?offset=50&limit=50",
+      },
+    };
+    const page2 = { items: [albTrack(50), albTrack(51), null, albTrack(52)], next: null };
+    const http = {
+      get: vi
+        .fn()
+        .mockResolvedValueOnce({ data: albumPayload }) // GET /v1/albums/alb1
+        .mockResolvedValueOnce({ data: page2 }), // GET /v1/albums/alb1/tracks
+    } as any;
+    const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+    const out = await api.getAlbumTracks("alb1");
+
+    expect(http.get).toHaveBeenCalledTimes(2);
+    expect(out).toHaveLength(53); // 50 + 3 real (one null dropped)
+    for (const t of out) {
+      expect(t.album).toBe("Big Compilation");
+      expect(t.coverUrl).toBe("https://i.scdn.co/big.jpg");
+      expect(t.platform).toBe("spotify");
+    }
+    expect(out[0].id).toBe("a0");
+    expect(out[49].id).toBe("a49");
+    expect(out[50].id).toBe("a50"); // page 2 appended in order
+    expect(out[52].id).toBe("a52");
+  });
+
+  // Robustness: a malformed/proxy response of { items: [], next: <non-null> } never
+  // grows songs.length nor nulls `next`, so a while-loop bounded ONLY by
+  // songs.length >= cap spins forever. getAlbumTracks must have a hard offset/page
+  // bound (mirroring the playlist loop) so it TERMINATES regardless of items/next.
+  it("terminates on a { items: [], next: <non-null> } response (bounded call count, no hang)", async () => {
+    const auth = {
+      post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+    } as any;
+    const http = {
+      get: vi.fn().mockImplementation((path: string) => {
+        if (path === "/v1/albums/alb1") {
+          // Even the embedded first page is malformed: empty items, non-null next.
+          return Promise.resolve({
+            data: {
+              name: "Broken",
+              images: [{ url: "https://i.scdn.co/broken.jpg" }],
+              tracks: { items: [], next: "http://x/next" },
+            },
+          });
+        }
+        // Every /albums/{id}/tracks page keeps advertising a further page forever.
+        return Promise.resolve({ data: { items: [], next: "http://x/next" } });
+      }),
+    } as any;
+    const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+    const out = await api.getAlbumTracks("alb1");
+
+    // Returns what it has (nothing) rather than hanging.
+    expect(out).toEqual([]);
+    // Bounded: 1 album GET + at most MAX_ALBUM_TRACKS/ALBUM_PAGE_SIZE (=10) page fetches.
+    expect(http.get.mock.calls.length).toBeLessThanOrEqual(12);
+  });
+});
+
+// R2-7: search() must null-filter tracks.items like its album/playlist siblings so
+// an unavailable/relinked null track never becomes a bogus id:'' "Unknown" Song.
+describe("search track null-filtering (R2-7)", () => {
+  it("drops null and id-less track entries (never emits an empty-id 'Unknown' song)", async () => {
+    const auth = {
+      post: vi.fn().mockResolvedValue({ data: { access_token: "t", expires_in: 3600 } }),
+    } as any;
+    const http = {
+      get: vi.fn().mockResolvedValue({
+        data: {
+          tracks: {
+            items: [
+              null, // unavailable/relinked track
+              { id: "t1", name: "Real", artists: [{ name: "X" }], duration_ms: 1000 },
+              {}, // id-less → maps to {id:'', name:'Unknown'}, must also be dropped
+            ],
+          },
+          albums: { items: [] },
+          playlists: { items: [] },
+        },
+      }),
+    } as any;
+    const api = new SpotifyWebApi(() => ({ clientId: "a", clientSecret: "b" }), { http, auth });
+    const out = await api.search("x");
+
+    expect(out.songs).toHaveLength(1);
+    expect(out.songs[0].id).toBe("t1");
+    expect(out.songs.some((s) => s.id === "")).toBe(false);
+    expect(out.songs.some((s) => s.name === "Unknown")).toBe(false);
+  });
+});

src/music/spotify/webapi.ts

@@ -0,0 +1,232 @@
+import axios, { type AxiosInstance } from "axios";
+import type { Song, Album, Playlist, SearchResult } from "../provider.js";
+
+export interface SpotifyCreds {
+  clientId: string;
+  clientSecret: string;
+}
+
+const ACCOUNTS_BASE = "https://accounts.spotify.com";
+const API_BASE = "https://api.spotify.com";
+
+// Spotify pages collection tracks at 100 (playlists) / 50 (albums). Follow the
+// paging links, but bound the fan-out so a pathological 10k-track collection
+// can't explode into dozens of API calls; stop once the cap is reached.
+const PLAYLIST_PAGE_SIZE = 100;
+const ALBUM_PAGE_SIZE = 50;
+const MAX_PLAYLIST_TRACKS = 500;
+const MAX_ALBUM_TRACKS = 500;
+
+function artistsToString(artists: unknown): string {
+  return Array.isArray(artists)
+    ? artists.map((a: any) => a?.name).filter(Boolean).join(", ")
+    : "";
+}
+
+/** Map a Spotify track object (search / tracks / playlist item .track) to a Song. */
+export function mapSpotifyTrack(raw: any): Song {
+  return {
+    id: raw?.id ?? "",
+    name: raw?.name ?? "Unknown",
+    artist: artistsToString(raw?.artists),
+    album: raw?.album?.name ?? "",
+    duration: Math.round((raw?.duration_ms ?? 0) / 1000),
+    coverUrl: raw?.album?.images?.[0]?.url ?? "",
+    platform: "spotify",
+  };
+}
+
+export function mapSpotifyTracks(raw: any): Song[] {
+  return Array.isArray(raw) ? raw.map(mapSpotifyTrack) : [];
+}
+
+export function mapSpotifyAlbum(raw: any): Album {
+  return {
+    id: raw?.id ?? "",
+    name: raw?.name ?? "Unknown",
+    artist: artistsToString(raw?.artists),
+    coverUrl: raw?.images?.[0]?.url ?? "",
+    songCount: raw?.total_tracks ?? 0,
+    platform: "spotify",
+  };
+}
+
+export function mapSpotifyPlaylist(raw: any): Playlist {
+  return {
+    id: raw?.id ?? "",
+    name: raw?.name ?? "Unknown",
+    coverUrl: raw?.images?.[0]?.url ?? "",
+    songCount: raw?.tracks?.total ?? 0,
+    platform: "spotify",
+  };
+}
+
+/** True for the getSongUrl sentinel (spotify:track:<id>); real audio lands in Stage 2/3. */
+export function isSpotifyUri(url: string): boolean {
+  return typeof url === "string" && url.startsWith("spotify:");
+}
+
+export class SpotifyWebApi {
+  private getCreds: () => SpotifyCreds;
+  private http: AxiosInstance;
+  private auth: AxiosInstance;
+  private token = "";
+  private tokenExpiresAt = 0;
+
+  constructor(
+    getCreds: () => SpotifyCreds,
+    deps?: { http?: AxiosInstance; auth?: AxiosInstance }
+  ) {
+    this.getCreds = getCreds;
+    this.http = deps?.http ?? axios.create({ baseURL: API_BASE, timeout: 15_000 });
+    this.auth = deps?.auth ?? axios.create({ baseURL: ACCOUNTS_BASE, timeout: 15_000 });
+  }
+
+  setCreds(_c: SpotifyCreds): void {
+    // Creds are read live via getCreds(); force a token refresh on next call.
+    this.token = "";
+    this.tokenExpiresAt = 0;
+  }
+
+  hasCreds(): boolean {
+    const c = this.getCreds();
+    return !!c.clientId && !!c.clientSecret;
+  }
+
+  /** Client-Credentials app token, cached until ~30s before expiry. */
+  private async getToken(): Promise<string | null> {
+    if (!this.hasCreds()) return null;
+    if (this.token && Date.now() < this.tokenExpiresAt) return this.token;
+    const { clientId, clientSecret } = this.getCreds();
+    const basic = Buffer.from(`${clientId}:${clientSecret}`).toString("base64");
+    try {
+      const { data } = await this.auth.post(
+        "/api/token",
+        "grant_type=client_credentials",
+        {
+          headers: {
+            Authorization: `Basic ${basic}`,
+            "Content-Type": "application/x-www-form-urlencoded",
+          },
+        }
+      );
+      this.token = data?.access_token ?? "";
+      this.tokenExpiresAt = Date.now() + ((data?.expires_in ?? 3600) - 30) * 1000;
+      return this.token || null;
+    } catch {
+      return null;
+    }
+  }
+
+  private async get(
+    path: string,
+    params?: Record<string, unknown>,
+    retryOn429 = true
+  ): Promise<any | null> {
+    const token = await this.getToken();
+    if (!token) return null;
+    try {
+      const { data } = await this.http.get(path, {
+        params,
+        headers: { Authorization: `Bearer ${token}` },
+      });
+      return data;
+    } catch (err: any) {
+      // Spotify rate-limits on a rolling 30s window (429 + Retry-After seconds).
+      // Retry once after the advised delay before giving up.
+      if (retryOn429 && err?.response?.status === 429) {
+        // Retry-After may be a non-numeric HTTP-date or empty string; Number(...)
+        // then yields NaN/0 and fires the single retry at 0ms, ignoring the advised
+        // backoff. Guard for a finite positive value (mirrors connect-api.ts).
+        const raw = Number(err.response?.headers?.["retry-after"]);
+        const retryAfter = Number.isFinite(raw) && raw > 0 ? raw : 1;
+        await new Promise((r) => setTimeout(r, Math.min(retryAfter, 10) * 1000));
+        return this.get(path, params, false);
+      }
+      return null;
+    }
+  }
+
+  async search(query: string, limit = 20): Promise<SearchResult> {
+    const data = await this.get("/v1/search", {
+      q: query,
+      type: "track,album,playlist",
+      limit,
+    });
+    if (!data) return { songs: [], playlists: [], albums: [] };
+    return {
+      // Mirror the album/playlist filtering: a null entry (unavailable/relinked
+      // track) must not become a bogus id:'' "Unknown" Song. Drop empty ids too.
+      songs: Array.isArray(data?.tracks?.items)
+        ? data.tracks.items
+            .filter(Boolean)
+            .map(mapSpotifyTrack)
+            .filter((s: Song) => s.id !== "")
+        : [],
+      albums: Array.isArray(data?.albums?.items)
+        ? data.albums.items.filter(Boolean).map(mapSpotifyAlbum)
+        : [],
+      playlists: Array.isArray(data?.playlists?.items)
+        ? data.playlists.items.filter(Boolean).map(mapSpotifyPlaylist)
+        : [],
+    };
+  }
+
+  async getTrack(id: string): Promise<Song | null> {
+    const data = await this.get(`/v1/tracks/${id}`);
+    return data ? mapSpotifyTrack(data) : null;
+  }
+
+  async getAlbumTracks(albumId: string): Promise<Song[]> {
+    // Album-track objects omit the album block; fetch the album cover once and inject it.
+    const album = await this.get(`/v1/albums/${albumId}`);
+    const cover = album?.images?.[0]?.url ?? "";
+    const albumName = album?.name ?? "";
+
+    // Page 1 (up to 50 tracks) is embedded in the album payload; the embedded
+    // paging object caps at 50, so follow its `next` via the dedicated
+    // /albums/{id}/tracks endpoint until exhausted or the cap is reached. The
+    // offset bound is a HARD termination guarantee (mirrors the playlist loop):
+    // a malformed/proxy response of { items: [], next: <non-null> } never grows
+    // songs.length nor nulls `next`, so a loop bounded only by songs.length would
+    // spin forever — the offset cap stops it regardless of items/next.
+    const songs: Song[] = [];
+    let page = album?.tracks;
+    let offset = ALBUM_PAGE_SIZE;
+    while (page && Array.isArray(page.items)) {
+      for (const t of page.items.filter(Boolean)) {
+        songs.push({ ...mapSpotifyTrack(t), album: albumName, coverUrl: cover });
+      }
+      if (!page.next || songs.length >= MAX_ALBUM_TRACKS || offset >= MAX_ALBUM_TRACKS) break;
+      page = await this.get(`/v1/albums/${albumId}/tracks`, {
+        limit: ALBUM_PAGE_SIZE,
+        offset,
+      });
+      offset += ALBUM_PAGE_SIZE;
+    }
+    return songs.slice(0, MAX_ALBUM_TRACKS);
+  }
+
+  async getPlaylistTracks(playlistId: string): Promise<Song[]> {
+    // A single limit:100 page silently truncates 100+ track playlists. Follow
+    // `data.next` (advancing offset) until exhausted or the cap is reached, so a
+    // 10k-track playlist can't fan out into 100 API calls.
+    const songs: Song[] = [];
+    for (let offset = 0; offset < MAX_PLAYLIST_TRACKS; offset += PLAYLIST_PAGE_SIZE) {
+      const data = await this.get(`/v1/playlists/${playlistId}/tracks`, {
+        limit: PLAYLIST_PAGE_SIZE,
+        offset,
+      });
+      const items = data?.items;
+      if (!Array.isArray(items)) break;
+      // Keep the null / {track:null} / id-less filtering across ALL pages.
+      const mapped = items
+        .map((it: any) => it?.track)
+        .filter((t: any) => t && t.id)
+        .map(mapSpotifyTrack);
+      songs.push(...mapped);
+      if (!data.next) break;
+    }
+    return songs.slice(0, MAX_PLAYLIST_TRACKS);
+  }
+}

src/music/youtube.ts

@@ -115,20 +115,26 @@ export class YouTubeProvider implements MusicProvider {
   readonly platform = "youtube" as const;
   private quality = "bestaudio";
 
-  async search(query: string, limit = 5): Promise<SearchResult> {
+  async search(query: string, limit = 5, offset = 0): Promise<SearchResult> {
     try {
+      // yt-dlp's `ytsearchN` has no offset cursor — it always returns the first
+      // N results. Best-effort paginate by fetching offset+limit and slicing
+      // locally. (offset 0 → identical to before.)
+      const total = offset + limit;
       const raw = await runYtDlp([
-        `ytsearch${limit}:${query}`,
+        `ytsearch${total}:${query}`,
         "--dump-json",
         "--flat-playlist",
         "--no-warnings",
         "--quiet",
       ]);
       const lines = raw.trim().split("\n").filter(Boolean);
-      const songs: Song[] = lines.map((line) => {
-        const entry = JSON.parse(line) as YtDlpEntry;
-        return entryToSong(entry);
-      });
+      const songs: Song[] = lines
+        .slice(offset, offset + limit)
+        .map((line) => {
+          const entry = JSON.parse(line) as YtDlpEntry;
+          return entryToSong(entry);
+        });
       return { songs, playlists: [], albums: [] };
     } catch {
       return { songs: [], playlists: [], albums: [] };

src/ts-protocol/client-groups.test.ts

@@ -1,4 +1,4 @@
-import { describe, it, expect, vi } from "vitest";
+import { afterEach, describe, it, expect, vi } from "vitest";
 import pino from "pino";
 import { TS3Client } from "./client.js";
 
@@ -83,3 +83,59 @@ describe("TS3Client.getClientServerGroups — live query + parse smoke test", ()
     expect(await ts.getClientServerGroups(5)).toEqual([]);
   });
 });
+
+describe("TS3Client stable identity UID", () => {
+  it("derives the same client UID after exporting and restoring an identity", () => {
+    const first = makeClient();
+    const restored = new TS3Client(
+      {
+        host: "localhost",
+        port: 9987,
+        queryPort: 10011,
+        nickname: "RestoredBot",
+        identity: first.getIdentityExport(),
+      },
+      pino({ level: "silent" }),
+    );
+
+    expect(first.getClientUid()).toBeTruthy();
+    expect(restored.getClientUid()).toBe(first.getClientUid());
+  });
+});
+
+type VisibleUidHarness = {
+  visibleClientUids: Map<number, string>;
+  rememberVisibleClientUid(clientId: number, clientUid: string): void;
+  releaseVisibleClientUid(clientId: number): void;
+  clearVisibleClientUids(): void;
+};
+
+describe("TS3Client visible client UID grace", () => {
+  afterEach(() => vi.useRealTimers());
+
+  it("retains a leaving client's UID for final reordered voice packets", () => {
+    vi.useFakeTimers();
+    const cache = makeClient() as unknown as VisibleUidHarness;
+    cache.rememberVisibleClientUid(7, "managed-bot-uid=");
+
+    cache.releaseVisibleClientUid(7);
+    vi.advanceTimersByTime(999);
+    expect(cache.visibleClientUids.get(7)).toBe("managed-bot-uid=");
+
+    vi.advanceTimersByTime(1);
+    expect(cache.visibleClientUids.has(7)).toBe(false);
+  });
+
+  it("lets a new clientEnter overwrite a reused id and cancel stale cleanup", () => {
+    vi.useFakeTimers();
+    const cache = makeClient() as unknown as VisibleUidHarness;
+    cache.rememberVisibleClientUid(7, "old-managed-bot-uid=");
+    cache.releaseVisibleClientUid(7);
+
+    cache.rememberVisibleClientUid(7, "new-human-uid=");
+    vi.advanceTimersByTime(1_000);
+
+    expect(cache.visibleClientUids.get(7)).toBe("new-human-uid=");
+    cache.clearVisibleClientUids();
+  });
+});

src/ts-protocol/client.ts

@@ -3,6 +3,7 @@ import { Readable } from "node:stream";
 import {
   Client as TS3FullClient,
   generateIdentity as genTS3Identity,
+  getUidFromPublicKey,
   identityFromString,
   sendTextMessage,
   listChannels,
@@ -15,6 +16,7 @@ import {
   type ClientInfo,
   type ClientLeftViewEvent,
   type ClientMovedEvent,
+  type VoiceData,
   type FileUploadInfo,
 } from "@honeybbq/teamspeak-client";
 import type { Logger } from "../logger.js";
@@ -23,6 +25,10 @@ import {
   type ServerProtocol,
 } from "./protocol-detect.js";
 import { TS6HttpQuery } from "./http-query.js";
+import {
+  TrackingVoiceEndpointResolver,
+  type ResolvedVoiceEndpoint,
+} from "./voice-endpoint.js";
 
 export { CODEC_OPUS_MUSIC } from "./voice.js";
 export type { ServerProtocol } from "./protocol-detect.js";
@@ -65,6 +71,20 @@ export interface TS3TextMessage {
   invokerGroups: string[]; // sender's TS server-group ids; [] when not in view cache
 }
 
+/** Lightweight voice-packet signal used for activity detection. The encoded
+ * payload is intentionally not forwarded beyond this protocol wrapper. */
+export interface TS3VoiceActivity {
+  clientId: number;
+  codec: number;
+  /** Stable TeamSpeak identity when the sender is present in the client view. */
+  clientUid?: string;
+}
+
+// Command notifications and UDP voice packets can be reordered in flight.
+// Retain a leaving client's UID briefly so its final packet is still
+// attributable; a new clientEnter for the same id cancels and overwrites it.
+const VISIBLE_CLIENT_UID_RELEASE_GRACE_MS = 1_000;
+
 /**
  * Map the library's TextMessage to our wrapper. Preserves invokerGroups (the
  * sender's TS server groups), which the library populates only when the sender
@@ -85,12 +105,19 @@ export function toTS3TextMessage(msg: TextMessage): TS3TextMessage {
 export class TS3Client extends EventEmitter {
   private client: TS3FullClient | null = null;
   private identity: Identity;
+  private readonly clientUid: string;
   private clientId = 0;
+  private readonly visibleClientUids = new Map<number, string>();
+  private readonly visibleClientUidReleaseTimers = new Map<
+    number,
+    ReturnType<typeof setTimeout>
+  >();
   private logger: Logger;
   private disconnecting = false;
   private detectedProtocol: ServerProtocol = "unknown";
   private httpQuery: TS6HttpQuery | null = null;
   private udpErrorTimer: ReturnType<typeof setTimeout> | null = null;
+  private readonly voiceEndpointResolver = new TrackingVoiceEndpointResolver();
 
   constructor(private options: TS3ClientOptions, logger: Logger) {
     super();
@@ -101,6 +128,7 @@ export class TS3Client extends EventEmitter {
     } else {
       this.identity = genTS3Identity(8);
     }
+    this.clientUid = getUidFromPublicKey(this.identity.publicKeyBase64());
   }
 
   /** The detected (or forced) server protocol after connect(). */
@@ -114,6 +142,8 @@ export class TS3Client extends EventEmitter {
   }
 
   async connect(): Promise<void> {
+    this.voiceEndpointResolver.reset();
+    this.clearVisibleClientUids();
     // Clean up any existing connection before creating a new one
     if (this.client) {
       this.logger.info("Cleaning up previous connection before reconnecting");
@@ -213,6 +243,7 @@ export class TS3Client extends EventEmitter {
       // Forward server password to the protocol library so it can be
       // included in clientinit for password-protected servers
       serverPassword: this.options.serverPassword,
+      resolver: this.voiceEndpointResolver,
       logger: {
         debug: (msg) => this.logger.debug(msg),
         info: (msg) => this.logger.info(msg),
@@ -222,16 +253,32 @@ export class TS3Client extends EventEmitter {
     });
 
     this.client.on("textMessage", (msg: TextMessage) => {
+      if (msg.invokerID === this.clientId) return;
       this.emit("textMessage", toTS3TextMessage(msg));
     });
 
+    this.client.on("voiceData", (voice: VoiceData) => {
+      // The library normally suppresses our own packets; retain the explicit
+      // guard so a future protocol change cannot make a bot duck itself.
+      if (voice.clientId === this.clientId) return;
+      const clientUid = this.visibleClientUids.get(voice.clientId);
+      const activity: TS3VoiceActivity = {
+        clientId: voice.clientId,
+        codec: voice.codec,
+        ...(clientUid ? { clientUid } : {}),
+      };
+      this.emit("voiceActivity", activity);
+    });
+
     this.client.on("disconnected", (err) => {
       this.logger.warn({ err: err?.message }, "Connection closed");
       this.clientId = 0;
+      this.clearVisibleClientUids();
       this.emit("disconnected");
     });
 
     this.client.on("clientEnter", (info: ClientInfo) => {
+      this.rememberVisibleClientUid(info.id, info.uid);
       this.logger.debug(
         { nickname: info.nickname, id: info.id },
         "Client entered"
@@ -240,6 +287,7 @@ export class TS3Client extends EventEmitter {
     });
 
     this.client.on("clientLeave", (ev: ClientLeftViewEvent) => {
+      this.releaseVisibleClientUid(ev.id);
       this.logger.debug({ id: ev.id }, "Client left");
       this.emit("clientLeave", ev);
     });
@@ -429,6 +477,52 @@ export class TS3Client extends EventEmitter {
     return this.clientId;
   }
 
+  /** Actual endpoint selected by the SDK's SRV/TSDNS discovery and DNS lookup. */
+  getResolvedVoiceEndpoint(): ResolvedVoiceEndpoint | null {
+    return this.voiceEndpointResolver.getEndpoint();
+  }
+
+  /** Stable identity of this managed TeamSpeak client. */
+  getClientUid(): string {
+    return this.clientUid;
+  }
+
+  private rememberVisibleClientUid(clientId: number, clientUid: string): void {
+    const pendingRelease = this.visibleClientUidReleaseTimers.get(clientId);
+    if (pendingRelease) clearTimeout(pendingRelease);
+    this.visibleClientUidReleaseTimers.delete(clientId);
+
+    if (clientId > 0 && clientUid) {
+      this.visibleClientUids.set(clientId, clientUid);
+    } else {
+      this.visibleClientUids.delete(clientId);
+    }
+  }
+
+  private releaseVisibleClientUid(clientId: number): void {
+    const clientUid = this.visibleClientUids.get(clientId);
+    if (!clientUid) return;
+
+    const previous = this.visibleClientUidReleaseTimers.get(clientId);
+    if (previous) clearTimeout(previous);
+    const timer = setTimeout(() => {
+      if (this.visibleClientUids.get(clientId) === clientUid) {
+        this.visibleClientUids.delete(clientId);
+      }
+      this.visibleClientUidReleaseTimers.delete(clientId);
+    }, VISIBLE_CLIENT_UID_RELEASE_GRACE_MS);
+    timer.unref?.();
+    this.visibleClientUidReleaseTimers.set(clientId, timer);
+  }
+
+  private clearVisibleClientUids(): void {
+    for (const timer of this.visibleClientUidReleaseTimers.values()) {
+      clearTimeout(timer);
+    }
+    this.visibleClientUidReleaseTimers.clear();
+    this.visibleClientUids.clear();
+  }
+
   disconnect(): void {
     if (this.client && !this.disconnecting) {
       this.disconnecting = true;
@@ -441,6 +535,7 @@ export class TS3Client extends EventEmitter {
       });
     }
     this.clientId = 0;
+    this.clearVisibleClientUids();
     this.httpQuery = null;
     this.detectedProtocol = "unknown";
     if (this.udpErrorTimer) {

src/ts-protocol/voice-endpoint.test.ts

@@ -0,0 +1,79 @@
+import { describe, expect, it, vi } from "vitest";
+import type { AddrResolver, ResolvedAddr } from "@honeybbq/teamspeak-client";
+import { TrackingVoiceEndpointResolver } from "./voice-endpoint.js";
+
+function result(addr: string): ResolvedAddr {
+  return { addr, source: "test", expiry: new Date(0) };
+}
+
+function delegate(...addresses: string[]): AddrResolver {
+  return {
+    resolve: vi.fn(async () => addresses.map(result)),
+  };
+}
+
+describe("TrackingVoiceEndpointResolver", () => {
+  it("pins a DNS alias to the IPv4 endpoint used by the UDP connection", async () => {
+    const resolveHost = vi.fn(async () => "203.0.113.20");
+    const resolver = new TrackingVoiceEndpointResolver(
+      delegate("voice-alias.example.com:9987"),
+      resolveHost,
+    );
+
+    const resolved = await resolver.resolve("voice.example.com:9987");
+
+    expect(resolveHost).toHaveBeenCalledWith("voice-alias.example.com");
+    expect(resolved[0]?.addr).toBe("203.0.113.20:9987");
+    expect(resolver.getEndpoint()).toEqual({ host: "203.0.113.20", port: 9987 });
+  });
+
+  it("preserves the port chosen by SRV/TSDNS discovery", async () => {
+    const resolver = new TrackingVoiceEndpointResolver(
+      delegate("srv-target.example.com:12000"),
+      async () => "198.51.100.8",
+    );
+
+    expect((await resolver.resolve("voice.example.com:9987"))[0]?.addr).toBe(
+      "198.51.100.8:12000",
+    );
+    expect(resolver.getEndpoint()?.port).toBe(12000);
+  });
+
+  it("keeps the SDK target as a safe fallback when A-record lookup fails", async () => {
+    const original = "voice.example.com:9987";
+    const resolver = new TrackingVoiceEndpointResolver(
+      delegate(original),
+      async () => {
+        throw new Error("dns unavailable");
+      },
+    );
+
+    expect((await resolver.resolve(original))[0]?.addr).toBe(original);
+    expect(resolver.getEndpoint()).toEqual({ host: "voice.example.com", port: 9987 });
+  });
+
+  it("does not mutate secondary SDK candidates", async () => {
+    const resolver = new TrackingVoiceEndpointResolver(
+      delegate("first.example.com:9987", "second.example.com:9988"),
+      async () => "192.0.2.4",
+    );
+
+    const resolved = await resolver.resolve("voice.example.com:9987");
+    expect(resolved.map((candidate) => candidate.addr)).toEqual([
+      "192.0.2.4:9987",
+      "second.example.com:9988",
+    ]);
+  });
+
+  it("clears the observed endpoint before a reconnect", async () => {
+    const resolver = new TrackingVoiceEndpointResolver(
+      delegate("voice.example.com:9987"),
+      async () => "192.0.2.5",
+    );
+    await resolver.resolve("voice.example.com:9987");
+
+    resolver.reset();
+
+    expect(resolver.getEndpoint()).toBeNull();
+  });
+});

src/ts-protocol/voice-endpoint.ts

@@ -0,0 +1,104 @@
+import { lookup } from "node:dns/promises";
+import { isIP } from "node:net";
+import { Resolver } from "@honeybbq/teamspeak-client/discovery";
+import type {
+  AddrResolver,
+  ResolvedAddr,
+} from "@honeybbq/teamspeak-client";
+
+export interface ResolvedVoiceEndpoint {
+  host: string;
+  port: number;
+}
+
+type ResolveIpv4 = (host: string) => Promise<string>;
+
+function parseVoiceAddress(address: string): ResolvedVoiceEndpoint | null {
+  let host: string;
+  let rawPort: string;
+
+  if (address.startsWith("[")) {
+    const closingBracket = address.indexOf("]");
+    if (closingBracket < 0 || address[closingBracket + 1] !== ":") return null;
+    host = address.slice(1, closingBracket);
+    rawPort = address.slice(closingBracket + 2);
+  } else {
+    const separator = address.lastIndexOf(":");
+    if (separator <= 0) return null;
+    host = address.slice(0, separator);
+    rawPort = address.slice(separator + 1);
+  }
+
+  const port = Number(rawPort);
+  if (
+    host.length === 0 ||
+    !Number.isInteger(port) ||
+    port < 1 ||
+    port > 65_535
+  ) {
+    return null;
+  }
+  return { host, port };
+}
+
+function formatVoiceAddress(endpoint: ResolvedVoiceEndpoint): string {
+  return endpoint.host.includes(":")
+    ? `[${endpoint.host}]:${endpoint.port}`
+    : `${endpoint.host}:${endpoint.port}`;
+}
+
+async function resolveIpv4(host: string): Promise<string> {
+  if (isIP(host) === 4) return host;
+  return (await lookup(host, { family: 4 })).address;
+}
+
+/**
+ * Uses the SDK's normal SRV/TSDNS discovery, then pins its selected hostname
+ * to the IPv4 address that the UDP connection will use. Besides making the
+ * connection target observable, this gives all bots a common registry scope
+ * when one is configured with a DNS alias and another with the underlying IP.
+ */
+export class TrackingVoiceEndpointResolver implements AddrResolver {
+  private endpoint: ResolvedVoiceEndpoint | null = null;
+
+  constructor(
+    private readonly delegate: AddrResolver = new Resolver(),
+    private readonly resolveHost: ResolveIpv4 = resolveIpv4,
+  ) {}
+
+  async resolve(input: string, signal?: AbortSignal): Promise<ResolvedAddr[]> {
+    this.endpoint = null;
+    const candidates = await this.delegate.resolve(input, signal);
+    const selected = candidates[0];
+    if (!selected) return candidates;
+
+    const parsed = parseVoiceAddress(selected.addr);
+    if (!parsed) return candidates;
+
+    try {
+      const pinned = {
+        host: await this.resolveHost(parsed.host),
+        port: parsed.port,
+      };
+      this.endpoint = pinned;
+      return [
+        { ...selected, addr: formatVoiceAddress(pinned) },
+        ...candidates.slice(1),
+      ];
+    } catch {
+      // Preserve the SDK's original target if local A-record resolution fails.
+      // The connection may still succeed through platform-specific resolution;
+      // the registry then falls back to the logical host + resolved port.
+      this.endpoint = parsed;
+      return candidates;
+    }
+  }
+
+  reset(): void {
+    this.endpoint = null;
+  }
+
+  getEndpoint(): ResolvedVoiceEndpoint | null {
+    return this.endpoint ? { ...this.endpoint } : null;
+  }
+}

src/web/api/auth.test.ts

@@ -0,0 +1,74 @@
+import { describe, it, expect, vi } from "vitest";
+import express from "express";
+import request from "supertest";
+import pino from "pino";
+import type { MusicProvider } from "../../music/provider.js";
+import { getDefaultConfig, type JellyfinConfig } from "../../data/config.js";
+import { createAuthRouter } from "./auth.js";
+
+function fakeProvider(platform: MusicProvider["platform"]): MusicProvider {
+  return { platform } as unknown as MusicProvider;
+}
+
+describe("auth router POST /jellyfin/test", () => {
+  function mount(
+    stored: Partial<JellyfinConfig>,
+    user: unknown = { role: "admin" },
+  ) {
+    const config = getDefaultConfig();
+    Object.assign(config.jellyfin, stored);
+    const testConnection = vi.fn().mockResolvedValue({ ok: true, serverName: "JF" });
+    const jellyfin = { platform: "jellyfin", testConnection } as unknown as MusicProvider;
+    const app = express();
+    app.use(express.json());
+    app.use((req, _res, next) => { (req as { user?: unknown }).user = user; next(); });
+    app.use(
+      "/api/auth",
+      createAuthRouter(
+        fakeProvider("netease"), fakeProvider("qq"), fakeProvider("bilibili"),
+        pino({ level: "silent" }), undefined, undefined, undefined, jellyfin, config,
+      ),
+    );
+    return { app, testConnection };
+  }
+
+  it("fills empty credential fields from the stored config (masked password case)", async () => {
+    const { app, testConnection } = mount({
+      serverUrl: "https://old.example.com",
+      username: "bob",
+      password: "stored-pw",
+    });
+    const res = await request(app)
+      .post("/api/auth/jellyfin/test")
+      .send({ serverUrl: "https://new.example.com", username: "bob", password: "" });
+    expect(res.status).toBe(200);
+    expect(res.body.ok).toBe(true);
+    expect(testConnection).toHaveBeenCalledWith(
+      expect.objectContaining({
+        serverUrl: "https://new.example.com",
+        username: "bob",
+        password: "stored-pw",
+      }),
+    );
+  });
+
+  it("passes freshly entered credentials through", async () => {
+    const { app, testConnection } = mount({});
+    await request(app).post("/api/auth/jellyfin/test").send({
+      serverUrl: "https://jf.example.com",
+      authMode: "apikey",
+      apiKey: "key123",
+      userId: "u1",
+    });
+    expect(testConnection).toHaveBeenCalledWith(
+      expect.objectContaining({ authMode: "apikey", apiKey: "key123", userId: "u1" }),
+    );
+  });
+
+  it("is 403 for a member lacking platform.auth", async () => {
+    const { app, testConnection } = mount({}, { role: "member", capabilities: new Set([]) });
+    const res = await request(app).post("/api/auth/jellyfin/test").send({});
+    expect(res.status).toBe(403);
+    expect(testConnection).not.toHaveBeenCalled();
+  });
+});

src/web/api/auth.ts

@@ -3,6 +3,7 @@ import type { MusicProvider } from "../../music/provider.js";
 import { YouTubeProvider } from "../../music/youtube.js";
 import type { CookieStore } from "../../music/auth.js";
 import type { Logger } from "../../logger.js";
+import type { BotConfig, JellyfinConfig } from "../../data/config.js";
 import { requirePermission } from "../middleware/requirePermission.js";
 import { requireNotGuest } from "../middleware/requireNotGuest.js";
 
@@ -11,7 +12,11 @@ export function createAuthRouter(
   qqProvider: MusicProvider,
   bilibiliProvider: MusicProvider,
   logger: Logger,
-  cookieStore?: CookieStore
+  cookieStore?: CookieStore,
+  kugouProvider?: MusicProvider,
+  spotifyProvider?: MusicProvider,
+  jellyfinProvider?: MusicProvider,
+  config?: BotConfig
 ): Router {
   const router = Router();
   // YouTube is auth-less; we only use this instance so /auth/status can
@@ -21,6 +26,9 @@ export function createAuthRouter(
   function getProvider(platform?: string): MusicProvider {
     if (platform === "bilibili") return bilibiliProvider;
     if (platform === "youtube") return youtubeProvider;
+    if (platform === "kugou" && kugouProvider) return kugouProvider;
+    if (platform === "spotify" && spotifyProvider) return spotifyProvider;
+    if (platform === "jellyfin" && jellyfinProvider) return jellyfinProvider;
     return platform === "qq" ? qqProvider : neteaseProvider;
   }
 
@@ -65,6 +73,7 @@ export function createAuthRouter(
       if (status === "confirmed") {
         const cookie = provider.getCookie();
         const plat = (platform as string) === "bilibili" ? "bilibili" as const
+          : (platform as string) === "kugou" ? "kugou" as const
           : (platform as string) === "qq" ? "qq" as const : "netease" as const;
         if (cookie && cookieStore) {
           cookieStore.save(plat, cookie);
@@ -79,6 +88,45 @@ export function createAuthRouter(
     }
   });
 
+  // Jellyfin has no QR/cookie flow — the connection is admin-configured. This
+  // round-trips /System/Info so Settings can verify form values BEFORE saving.
+  // Empty/missing credential fields fall back to the stored config, so a
+  // masked (not re-entered) password still tests the live setup.
+  router.post("/jellyfin/test", requirePermission("platform.auth"), async (req, res) => {
+    const testable = jellyfinProvider as
+      | (MusicProvider & {
+          testConnection?: (
+            candidate?: JellyfinConfig,
+          ) => Promise<{ ok: boolean; serverName?: string; version?: string; error?: string }>;
+        })
+      | undefined;
+    if (!testable?.testConnection) {
+      res.status(501).json({ error: "Jellyfin provider not available" });
+      return;
+    }
+    try {
+      const body = (req.body ?? {}) as Partial<JellyfinConfig>;
+      const stored = config?.jellyfin;
+      const str = (v: unknown, fallback: string) =>
+        typeof v === "string" && v.trim() !== "" ? v.trim() : fallback;
+      const candidate: JellyfinConfig = {
+        serverUrl: str(body.serverUrl, stored?.serverUrl ?? ""),
+        authMode:
+          body.authMode === "apikey" || body.authMode === "userpass"
+            ? body.authMode
+            : stored?.authMode ?? "userpass",
+        username: str(body.username, stored?.username ?? ""),
+        password: str(body.password, stored?.password ?? ""),
+        apiKey: str(body.apiKey, stored?.apiKey ?? ""),
+        userId: str(body.userId, stored?.userId ?? ""),
+      };
+      res.json(await testable.testConnection(candidate));
+    } catch (err) {
+      logger.error({ err }, "Jellyfin test connection failed");
+      res.status(500).json({ error: (err as Error).message });
+    }
+  });
+
   router.post("/sms/send", requirePermission("platform.auth"), async (req, res) => {
     try {
       const { phone } = req.body;
@@ -134,9 +182,18 @@ export function createAuthRouter(
         .json({ error: "YouTube does not use cookies (uses yt-dlp binary)" });
       return;
     }
+    // Jellyfin auth is server-configured (Settings → connection card), not
+    // cookie-based; falling through would clobber the NetEase cookie entry.
+    if (platform === "jellyfin") {
+      res
+        .status(400)
+        .json({ error: "Jellyfin 通过 Settings 配置连接，不支持手动 Cookie" });
+      return;
+    }
     const provider = getProvider(platform);
     provider.setCookie(cookie);
     const plat = platform === "bilibili" ? "bilibili" as const
+      : platform === "kugou" ? "kugou" as const
       : platform === "qq" ? "qq" as const : "netease" as const;
     if (cookieStore) {
       cookieStore.save(plat, cookie);

src/web/api/bot.test.ts

@@ -3,7 +3,7 @@ import express from "express";
 import cookieParser from "cookie-parser";
 import request from "supertest";
 import pino from "pino";
-import { mkdtempSync, rmSync } from "node:fs";
+import { mkdtempSync, rmSync, readFileSync, existsSync } from "node:fs";
 import { tmpdir } from "node:os";
 import { join } from "node:path";
 import { createDatabase, type BotDatabase } from "../../data/database.js";
@@ -13,21 +13,30 @@ import { createAvatarStore } from "../../data/avatars.js";
 import { createRequireAuth } from "../middleware/requireAuth.js";
 import { createPermissionStore } from "../../data/permissions.js";
 import { createBotRouter } from "./bot.js";
-import { getDefaultConfig, type BotConfig } from "../../data/config.js";
+import {
+  getDefaultConfig,
+  type BotConfig,
+  type JellyfinConfig,
+  type VoiceDuckingConfig,
+} from "../../data/config.js";
 import { SESSION_COOKIE_NAME } from "../auth/validateSession.js";
 import type { BotManager } from "../../bot/manager.js";
 
-/** Records every updateIdleTimeout / updateAutoPause call so the test can assert propagation. */
+/** Records live settings updates so the tests can assert per-bot propagation. */
 function makeFakeBot() {
   return {
     idleTimeoutCalls: [] as number[],
     autoPauseCalls: [] as boolean[],
+    voiceDuckingCalls: [] as VoiceDuckingConfig[],
     updateIdleTimeout(minutes: number) {
       this.idleTimeoutCalls.push(minutes);
     },
     updateAutoPause(enabled: boolean) {
       this.autoPauseCalls.push(enabled);
     },
+    updateVoiceDucking(settings: VoiceDuckingConfig) {
+      this.voiceDuckingCalls.push({ ...settings });
+    },
   };
 }
 
@@ -84,6 +93,60 @@ describe("bot router /settings", () => {
     expect(res.body.autoPauseOnEmpty).toBe(true);
   });
 
+  it("GET /settings includes voiceDucking with safe defaults", async () => {
+    const res = await request(app).get("/api/bot/settings").set("Cookie", cookie);
+    expect(res.status).toBe(200);
+    expect(res.body.voiceDucking).toEqual({ enabled: false, volumePercent: 30 });
+  });
+
+  it("POST /settings safely partial-merges, persists and hot-applies voiceDucking", async () => {
+    const enable = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ voiceDucking: { enabled: true } });
+    expect(enable.status).toBe(200);
+    expect(enable.body.voiceDucking).toEqual({ enabled: true, volumePercent: 30 });
+
+    const setVolume = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ voiceDucking: { volumePercent: 42.5 } });
+    expect(setVolume.status).toBe(200);
+    expect(config.voiceDucking).toEqual({ enabled: true, volumePercent: 42.5 });
+
+    for (const bot of fakeBots) {
+      expect(bot.voiceDuckingCalls).toEqual([
+        { enabled: true, volumePercent: 30 },
+        { enabled: true, volumePercent: 42.5 },
+      ]);
+    }
+
+    const persisted = JSON.parse(readFileSync(configPath, "utf-8"));
+    expect(persisted.voiceDucking).toEqual({ enabled: true, volumePercent: 42.5 });
+    const followUp = await request(app).get("/api/bot/settings").set("Cookie", cookie);
+    expect(followUp.body.voiceDucking).toEqual({ enabled: true, volumePercent: 42.5 });
+  });
+
+  it("POST /settings ignores malformed voiceDucking fields and non-object blocks", async () => {
+    config.voiceDucking = { enabled: true, volumePercent: 25 };
+    const invalidFields = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ voiceDucking: { enabled: "yes", volumePercent: 101 } });
+    expect(invalidFields.status).toBe(200);
+    expect(config.voiceDucking).toEqual({ enabled: true, volumePercent: 25 });
+
+    const arrayBlock = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ voiceDucking: [{ enabled: false, volumePercent: 0 }] });
+    expect(arrayBlock.status).toBe(200);
+    expect(config.voiceDucking).toEqual({ enabled: true, volumePercent: 25 });
+    for (const bot of fakeBots) {
+      expect(bot.voiceDuckingCalls).toEqual([{ enabled: true, volumePercent: 25 }]);
+    }
+  });
+
   it("POST /settings with autoPauseOnEmpty:false persists and propagates to bots", async () => {
     const res = await request(app)
       .post("/api/bot/settings")
@@ -196,6 +259,336 @@ describe("bot router /settings", () => {
     expect(res.status).toBe(200);
     expect(config.adminGroups).toEqual([6]);
   });
+
+  it("GET /settings includes a masked spotify block (hasClientSecret, never a raw secret)", async () => {
+    config.spotify.enabled = true;
+    config.spotify.backend = "librespot";
+    config.spotify.clientId = "cid-1";
+    config.spotify.deviceName = "MyDevice";
+    config.spotify.bitrate = 160;
+    config.spotify.clientSecret = "supersecret";
+
+    const withSecret = await request(app).get("/api/bot/settings").set("Cookie", cookie);
+    expect(withSecret.status).toBe(200);
+    expect(withSecret.body.spotify).toEqual({
+      enabled: true,
+      backend: "librespot",
+      clientId: "cid-1",
+      deviceName: "MyDevice",
+      bitrate: 160,
+      hasClientSecret: true,
+    });
+    // The raw secret is never serialized to the client.
+    expect(withSecret.body.spotify).not.toHaveProperty("clientSecret");
+
+    config.spotify.clientSecret = "";
+    const noSecret = await request(app).get("/api/bot/settings").set("Cookie", cookie);
+    expect(noSecret.body.spotify.hasClientSecret).toBe(false);
+    expect(noSecret.body.spotify).not.toHaveProperty("clientSecret");
+  });
+
+  it("POST /settings updates the spotify block, echoes the masked view, and persists", async () => {
+    const res = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ spotify: { enabled: true, backend: "librespot", clientId: "cid", deviceName: "Dev", bitrate: 160 } });
+    expect(res.status).toBe(200);
+    expect(config.spotify.enabled).toBe(true);
+    expect(config.spotify.backend).toBe("librespot");
+    expect(config.spotify.clientId).toBe("cid");
+    expect(config.spotify.deviceName).toBe("Dev");
+    expect(config.spotify.bitrate).toBe(160);
+
+    expect(res.body.spotify).toEqual({
+      enabled: true,
+      backend: "librespot",
+      clientId: "cid",
+      deviceName: "Dev",
+      bitrate: 160,
+      hasClientSecret: false,
+    });
+    expect(res.body.spotify).not.toHaveProperty("clientSecret");
+
+    // saveConfig persisted the block to disk.
+    expect(existsSync(configPath)).toBe(true);
+    const persisted = JSON.parse(readFileSync(configPath, "utf-8"));
+    expect(persisted.spotify.clientId).toBe("cid");
+    expect(persisted.spotify.backend).toBe("librespot");
+  });
+
+  it("POST /settings ignores an invalid spotify backend/bitrate (partial-merge, no 400)", async () => {
+    config.spotify.backend = "auto";
+    config.spotify.bitrate = 320;
+    const res = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ spotify: { backend: "bogus", bitrate: 999 } });
+    expect(res.status).toBe(200);
+    expect(config.spotify.backend).toBe("auto");
+    expect(config.spotify.bitrate).toBe(320);
+  });
+
+  it("POST /settings sets a non-empty clientSecret but a blank one never wipes it", async () => {
+    const set = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ spotify: { clientSecret: "newsecret" } });
+    expect(set.status).toBe(200);
+    expect(config.spotify.clientSecret).toBe("newsecret");
+    expect(set.body.spotify.hasClientSecret).toBe(true);
+    expect(set.body.spotify).not.toHaveProperty("clientSecret");
+
+    const blank = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ spotify: { clientSecret: "" } });
+    expect(blank.status).toBe(200);
+    expect(config.spotify.clientSecret).toBe("newsecret");
+    expect(blank.body.spotify.hasClientSecret).toBe(true);
+  });
+
+  it("POST /settings ignores a blank/whitespace deviceName but stores a trimmed non-empty one", async () => {
+    config.spotify.deviceName = "OldDevice";
+
+    // Empty string leaves the prior deviceName untouched.
+    const empty = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ spotify: { deviceName: "" } });
+    expect(empty.status).toBe(200);
+    expect(config.spotify.deviceName).toBe("OldDevice");
+    expect(empty.body.spotify.deviceName).toBe("OldDevice");
+
+    // Whitespace-only is likewise ignored (trim().length === 0).
+    const ws = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ spotify: { deviceName: "   " } });
+    expect(ws.status).toBe(200);
+    expect(config.spotify.deviceName).toBe("OldDevice");
+
+    // A non-empty value is stored TRIMMED.
+    const set = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ spotify: { deviceName: "  Dev  " } });
+    expect(set.status).toBe(200);
+    expect(config.spotify.deviceName).toBe("Dev");
+    expect(set.body.spotify.deviceName).toBe("Dev");
+  });
+
+  it("POST /settings that omits spotify leaves config.spotify untouched (no regression)", async () => {
+    config.spotify.clientId = "keep-me";
+    config.spotify.clientSecret = "keep-secret";
+    const before = { ...config.spotify };
+    const res = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ autoPauseOnEmpty: false });
+    expect(res.status).toBe(200);
+    expect(config.spotify).toEqual(before);
+  });
+
+  it("GET /settings echoes savedQueuesEnabled + playKeepsQueue (default false)", async () => {
+    const res = await request(app).get("/api/bot/settings").set("Cookie", cookie);
+    expect(res.status).toBe(200);
+    expect(res.body.savedQueuesEnabled).toBe(false);
+    expect(res.body.playKeepsQueue).toBe(false);
+  });
+
+  it("POST /settings persists savedQueuesEnabled and playKeepsQueue", async () => {
+    const res = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ savedQueuesEnabled: true, playKeepsQueue: true });
+    expect(res.status).toBe(200);
+    expect(res.body.savedQueuesEnabled).toBe(true);
+    expect(res.body.playKeepsQueue).toBe(true);
+    expect(config.savedQueuesEnabled).toBe(true);
+    expect(config.playKeepsQueue).toBe(true);
+
+    const get = await request(app).get("/api/bot/settings").set("Cookie", cookie);
+    expect(get.body.savedQueuesEnabled).toBe(true);
+    expect(get.body.playKeepsQueue).toBe(true);
+  });
+
+  it("POST /settings ignores non-boolean savedQueuesEnabled without 400", async () => {
+    const res = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ savedQueuesEnabled: "nope" });
+    expect(res.status).toBe(200);
+    expect(config.savedQueuesEnabled).toBe(false); // unchanged from default
+  });
+});
+
+// Whole-branch I2: saving a Client ID in Settings must re-configure the single
+// live SpotifyOAuth so the operator can Connect without a process restart.
+describe("bot router /settings applies spotify creds to the live OAuth (I2)", () => {
+  let botDb: BotDatabase;
+  let app: express.Express;
+  let cookie: string;
+  let config: BotConfig;
+  let configPath: string;
+  let tmpDir: string;
+  let configureCalls: Array<[string | undefined, string | undefined]>;
+
+  beforeEach(async () => {
+    botDb = createDatabase(":memory:");
+    const users = createUserStore(botDb.db);
+    const sessions = createSessionStore(botDb.db);
+    const alice = await users.createUser("alice", "pw-alice", "admin");
+    cookie = `${SESSION_COOKIE_NAME}=${sessions.createSession(alice.id).token}`;
+
+    tmpDir = mkdtempSync(join(tmpdir(), "botsettings-oauth-"));
+    configPath = join(tmpDir, "config.json");
+    config = getDefaultConfig(); // webPort defaults to 3000
+
+    const fakeManager = { getAllBots: () => [] } as unknown as BotManager;
+    const avatarStore = createAvatarStore(tmpDir);
+
+    // Fake OAuth recording every configure(clientId, redirectUri) call.
+    configureCalls = [];
+    const fakeOAuth = {
+      configure(clientId?: string, redirectUri?: string) {
+        configureCalls.push([clientId, redirectUri]);
+      },
+    };
+
+    app = express();
+    app.use(express.json());
+    app.use(cookieParser());
+    app.use("/api", createRequireAuth(sessions, createPermissionStore(botDb.db), () => getDefaultConfig().guestMode));
+    app.use(
+      "/api/bot",
+      createBotRouter(fakeManager, config, configPath, pino({ level: "silent" }), botDb, avatarStore, undefined, fakeOAuth),
+    );
+  });
+
+  afterEach(() => {
+    botDb.close();
+    rmSync(tmpDir, { recursive: true, force: true });
+  });
+
+  it("configures the live OAuth once with the derived callback redirectUri when a Client ID is saved", async () => {
+    const res = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ spotify: { clientId: "cid", enabled: true } });
+    expect(res.status).toBe(200);
+    expect(configureCalls).toEqual([
+      ["cid", `http://127.0.0.1:${config.webPort}/api/spotify/callback`],
+    ]);
+  });
+
+  it("does NOT touch the OAuth when the request has no spotify block", async () => {
+    const res = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ autoPauseOnEmpty: false });
+    expect(res.status).toBe(200);
+    expect(configureCalls).toEqual([]);
+  });
+
+  it("configures with ('', undefined) when a spotify block clears the Client ID (disables OAuth)", async () => {
+    const res = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ spotify: { clientId: "" } });
+    expect(res.status).toBe(200);
+    expect(configureCalls).toEqual([["", undefined]]);
+  });
+});
+
+// R2-4: saving Spotify creds in Settings must also refresh the Web API SEARCH
+// provider (spotifyProvider.setCreds), not only the OAuth playback path. Without
+// this, a fresh install (enabled defaults false) keeps empty search creds until a
+// full process restart even after an admin enters Client ID + Secret.
+describe("bot router /settings refreshes the Web API search provider creds (R2-4)", () => {
+  let botDb: BotDatabase;
+  let app: express.Express;
+  let cookie: string;
+  let config: BotConfig;
+  let configPath: string;
+  let tmpDir: string;
+  let setCredsCalls: Array<[string, string]>;
+  let configureCalls: Array<[string | undefined, string | undefined]>;
+
+  beforeEach(async () => {
+    botDb = createDatabase(":memory:");
+    const users = createUserStore(botDb.db);
+    const sessions = createSessionStore(botDb.db);
+    const alice = await users.createUser("alice", "pw-alice", "admin");
+    cookie = `${SESSION_COOKIE_NAME}=${sessions.createSession(alice.id).token}`;
+
+    tmpDir = mkdtempSync(join(tmpdir(), "botsettings-provider-"));
+    configPath = join(tmpDir, "config.json");
+    config = getDefaultConfig();
+
+    const fakeManager = { getAllBots: () => [] } as unknown as BotManager;
+    const avatarStore = createAvatarStore(tmpDir);
+
+    // Fake search provider recording every setCreds(clientId, clientSecret) call.
+    setCredsCalls = [];
+    const fakeProvider = {
+      setCreds(clientId: string, clientSecret: string) {
+        setCredsCalls.push([clientId, clientSecret]);
+      },
+    };
+    // Fake OAuth so we can assert the playback path is still wired alongside.
+    configureCalls = [];
+    const fakeOAuth = {
+      configure(clientId?: string, redirectUri?: string) {
+        configureCalls.push([clientId, redirectUri]);
+      },
+    };
+
+    app = express();
+    app.use(express.json());
+    app.use(cookieParser());
+    app.use("/api", createRequireAuth(sessions, createPermissionStore(botDb.db), () => getDefaultConfig().guestMode));
+    app.use(
+      "/api/bot",
+      createBotRouter(fakeManager, config, configPath, pino({ level: "silent" }), botDb, avatarStore, undefined, fakeOAuth, fakeProvider),
+    );
+  });
+
+  afterEach(() => {
+    botDb.close();
+    rmSync(tmpDir, { recursive: true, force: true });
+  });
+
+  it("calls setCreds once with (clientId, clientSecret) when a spotify block is saved (and OAuth is still configured)", async () => {
+    const res = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ spotify: { clientId: "cid", clientSecret: "sec", enabled: true } });
+    expect(res.status).toBe(200);
+    expect(setCredsCalls).toEqual([["cid", "sec"]]);
+    // The OAuth playback path is still wired on the same save.
+    expect(configureCalls.length).toBe(1);
+  });
+
+  it("does NOT call setCreds when the request has no spotify block", async () => {
+    const res = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ autoPauseOnEmpty: false });
+    expect(res.status).toBe(200);
+    expect(setCredsCalls).toEqual([]);
+  });
+
+  it("calls setCreds with the PRESERVED stored secret when the spotify block omits/blanks clientSecret", async () => {
+    config.spotify.clientId = "cid0";
+    config.spotify.clientSecret = "stored-secret";
+    const res = await request(app)
+      .post("/api/bot/settings")
+      .set("Cookie", cookie)
+      .send({ spotify: { clientId: "cid0", clientSecret: "", enabled: true } });
+    expect(res.status).toBe(200);
+    // Post-merge values: masked/blank secret must keep the stored one, never "".
+    expect(setCredsCalls).toEqual([["cid0", "stored-secret"]]);
+  });
 });
 
 describe("bot router /settings guest-mode gating + persistence", () => {
@@ -251,4 +644,152 @@ describe("bot router /settings guest-mode gating + persistence", () => {
     expect(res.body.guestMode.permissions.playNext).toBe(true);
     expect(res.body.guestMode.permissions.addToQueue).toBe(true); // untouched default
   });
+
+  it("POST /settings spotify write is 403 for a member lacking bot.manage", async () => {
+    const memberApp = mountBot(() => ({ role: "member", capabilities: new Set([]) }));
+    const res = await request(memberApp)
+      .post("/api/bot/settings")
+      .send({ spotify: { enabled: true, clientId: "cid" } });
+    expect(res.status).toBe(403);
+    // Gate rejected before any mutation.
+    expect(config.spotify.enabled).toBe(false);
+    expect(config.spotify.clientId).toBe("");
+  });
+});
+
+describe("bot router /settings jellyfin block + enabledProviders", () => {
+  let tmpDir: string;
+  let configPath: string;
+  let config: BotConfig;
+  let botDb: BotDatabase;
+  let configureCalls: JellyfinConfig[];
+
+  beforeEach(() => {
+    botDb = createDatabase(":memory:");
+    tmpDir = mkdtempSync(join(tmpdir(), "botsettings-jf-"));
+    configPath = join(tmpDir, "config.json");
+    config = getDefaultConfig();
+    configureCalls = [];
+  });
+
+  afterEach(() => {
+    botDb.close();
+    rmSync(tmpDir, { recursive: true, force: true });
+  });
+
+  function mountBot(): express.Express {
+    const fakeManager = { getAllBots: () => [] } as unknown as BotManager;
+    const avatarStore = createAvatarStore(tmpDir);
+    const app = express();
+    app.use(express.json());
+    app.use((req, _res, next) => { (req as { user?: unknown }).user = { role: "admin" }; next(); });
+    app.use(
+      "/api/bot",
+      createBotRouter(
+        fakeManager, config, configPath, pino({ level: "silent" }), botDb, avatarStore,
+        undefined, undefined, undefined,
+        { configure: (cfg: JellyfinConfig) => configureCalls.push({ ...cfg }) },
+      ),
+    );
+    return app;
+  }
+
+  it("GET /settings exposes a masked jellyfin block (no password/apiKey echo)", async () => {
+    config.jellyfin.serverUrl = "https://jf.example.com";
+    config.jellyfin.password = "secret";
+    const res = await request(mountBot()).get("/api/bot/settings");
+    expect(res.status).toBe(200);
+    expect(res.body.jellyfin).toEqual({
+      serverUrl: "https://jf.example.com",
+      authMode: "userpass",
+      username: "",
+      userId: "",
+      hasPassword: true,
+      hasApiKey: false,
+    });
+    // Default: online sources on, jellyfin opt-in (not listed).
+    expect(res.body.enabledProviders).toEqual(["netease", "qq", "bilibili", "youtube", "kugou"]);
+  });
+
+  it("POST /settings merges jellyfin, keeps stored secrets on blank, hot-configures", async () => {
+    config.jellyfin.password = "stored-pw";
+    const app = mountBot();
+    const res = await request(app).post("/api/bot/settings").send({
+      jellyfin: { serverUrl: "https://jf.example.com///", username: "bob", password: "" },
+    });
+    expect(res.status).toBe(200);
+    // Trailing slashes normalized; blank password kept the stored one.
+    expect(config.jellyfin.serverUrl).toBe("https://jf.example.com");
+    expect(config.jellyfin.username).toBe("bob");
+    expect(config.jellyfin.password).toBe("stored-pw");
+    expect(res.body.jellyfin.hasPassword).toBe(true);
+    // Live provider re-configured with the post-merge values.
+    expect(configureCalls).toHaveLength(1);
+    expect(configureCalls[0].serverUrl).toBe("https://jf.example.com");
+    expect(configureCalls[0].password).toBe("stored-pw");
+    // Persisted to disk.
+    const onDisk = JSON.parse(readFileSync(configPath, "utf-8"));
+    expect(onDisk.jellyfin.username).toBe("bob");
+  });
+
+  it("POST /settings filters enabledProviders to known providers", async () => {
+    const res = await request(mountBot()).post("/api/bot/settings").send({
+      enabledProviders: ["jellyfin", "netease", "bogus", 42],
+    });
+    expect(res.status).toBe(200);
+    expect(res.body.enabledProviders).toEqual(["jellyfin", "netease"]);
+    expect(config.enabledProviders).toEqual(["jellyfin", "netease"]);
+    // No jellyfin block in the request → no reconfigure call.
+    expect(configureCalls).toHaveLength(0);
+  });
+
+  // --- #126: operator-chosen default source ---
+
+  it("GET /settings exposes defaultPlatform (null by default)", async () => {
+    const res = await request(mountBot()).get("/api/bot/settings");
+    expect(res.status).toBe(200);
+    expect(res.body.defaultPlatform).toBeNull();
+  });
+
+  it("POST /settings sets an enabled defaultPlatform and persists it", async () => {
+    const res = await request(mountBot()).post("/api/bot/settings").send({
+      defaultPlatform: "bilibili",
+    });
+    expect(res.status).toBe(200);
+    expect(res.body.defaultPlatform).toBe("bilibili");
+    expect(config.defaultPlatform).toBe("bilibili");
+    const onDisk = JSON.parse(readFileSync(configPath, "utf-8"));
+    expect(onDisk.defaultPlatform).toBe("bilibili");
+  });
+
+  it("POST /settings ignores an unknown or disabled defaultPlatform", async () => {
+    const app = mountBot();
+    // jellyfin is opt-in and not enabled in the default config → rejected.
+    await request(app).post("/api/bot/settings").send({ defaultPlatform: "jellyfin" });
+    expect(config.defaultPlatform).toBeNull();
+    // Unknown value → rejected.
+    await request(app).post("/api/bot/settings").send({ defaultPlatform: "bogus" });
+    expect(config.defaultPlatform).toBeNull();
+  });
+
+  it("POST /settings clears defaultPlatform with null", async () => {
+    const app = mountBot();
+    await request(app).post("/api/bot/settings").send({ defaultPlatform: "qq" });
+    expect(config.defaultPlatform).toBe("qq");
+    const res = await request(app).post("/api/bot/settings").send({ defaultPlatform: null });
+    expect(res.body.defaultPlatform).toBeNull();
+    expect(config.defaultPlatform).toBeNull();
+  });
+
+  it("POST /settings drops a default whose source gets disabled in the same request", async () => {
+    const app = mountBot();
+    await request(app).post("/api/bot/settings").send({ defaultPlatform: "qq" });
+    expect(config.defaultPlatform).toBe("qq");
+    // Disabling qq via enabledProviders clears the now-invalid default.
+    const res = await request(app).post("/api/bot/settings").send({
+      enabledProviders: ["netease", "bilibili"],
+    });
+    expect(res.body.defaultPlatform).toBeNull();
+    expect(config.defaultPlatform).toBeNull();
+  });
 });

src/web/api/bot.ts

@@ -1,7 +1,7 @@
 import { Router } from "express";
 import type { BotManager } from "../../bot/manager.js";
-import type { BotConfig, GuestModeConfig } from "../../data/config.js";
-import { saveConfig } from "../../data/config.js";
+import type { BotConfig, GuestModeConfig, SpotifyConfig, JellyfinConfig, GateableProvider } from "../../data/config.js";
+import { saveConfig, GATEABLE_PROVIDERS } from "../../data/config.js";
 import type { Logger } from "../../logger.js";
 import type { BotDatabase } from "../../data/database.js";
 import type { AvatarStore } from "../../data/avatars.js";
@@ -17,9 +17,44 @@ export function createBotRouter(
   botDb: BotDatabase,
   avatarStore: AvatarStore,
   onGuestPolicyChanged?: (cfg: GuestModeConfig) => void,
+  // I2: the single process-wide OAuth, so a UI-entered Client ID reaches the
+  // live instance on save (no restart). Structural type = SpotifyOAuth.configure.
+  spotifyOAuth?: { configure(clientId?: string, redirectUri?: string): void },
+  // R2-4: the process-wide Web API SEARCH provider. Boot only wires creds when
+  // spotify.enabled is already true, so a fresh install that enables Spotify via
+  // Settings must push creds here too, or search stays empty until a restart.
+  // Structural type = SpotifyProvider.setCreds.
+  spotifyProvider?: { setCreds(clientId: string, clientSecret: string): void },
+  // The live JellyfinProvider, so a Settings save re-points the connection
+  // without a restart (configure() drops the cached token only when
+  // credential-relevant fields actually changed). Structural type =
+  // JellyfinProvider.configure.
+  jellyfinProvider?: { configure(cfg: JellyfinConfig): void },
 ): Router {
   const router = Router();
 
+  // Masked spotify view shared by the GET response and the POST echo. The raw
+  // clientSecret is write-only and NEVER serialized — only whether one is stored.
+  const maskedSpotify = () => ({
+    enabled: config.spotify.enabled,
+    backend: config.spotify.backend,
+    clientId: config.spotify.clientId,
+    deviceName: config.spotify.deviceName,
+    bitrate: config.spotify.bitrate,
+    hasClientSecret: config.spotify.clientSecret.length > 0,
+  });
+
+  // Masked jellyfin view: password and apiKey are write-only — only their
+  // presence is reported (mirrors maskedSpotify's clientSecret handling).
+  const maskedJellyfin = () => ({
+    serverUrl: config.jellyfin.serverUrl,
+    authMode: config.jellyfin.authMode,
+    username: config.jellyfin.username,
+    userId: config.jellyfin.userId,
+    hasPassword: config.jellyfin.password.length > 0,
+    hasApiKey: config.jellyfin.apiKey.length > 0,
+  });
+
   router.get("/", (req, res) => {
     const all = botManager.getAllBots().map((b) => b.getStatus());
     const u = req.user!;
@@ -36,16 +71,30 @@ export function createBotRouter(
     res.json({
       idleTimeoutMinutes: config.idleTimeoutMinutes ?? 0,
       autoPauseOnEmpty: config.autoPauseOnEmpty,
+      voiceDucking: config.voiceDucking,
       localAudioEnabled: config.localAudioEnabled,
+      savedQueuesEnabled: config.savedQueuesEnabled,
+      playKeepsQueue: config.playKeepsQueue,
       adminGroups: config.adminGroups ?? [],
       guestMode: config.guestMode,
+      spotify: maskedSpotify(),
+      jellyfin: maskedJellyfin(),
+      enabledProviders: config.enabledProviders,
+      defaultPlatform: config.defaultPlatform,
     });
   });
 
   // POST /api/bot/settings — 保存全局 bot 行为设置 (gated: changing global bot
   // behavior is a bot.manage operation, consistent with PR #80's permission model)
   router.post("/settings", requirePermission("bot.manage"), (req, res) => {
-    const { idleTimeoutMinutes, autoPauseOnEmpty, localAudioEnabled, guestMode, adminGroups } = req.body;
+    const {
+      idleTimeoutMinutes,
+      autoPauseOnEmpty,
+      localAudioEnabled,
+      voiceDucking,
+      guestMode,
+      adminGroups,
+    } = req.body;
 
     const hasIdle = idleTimeoutMinutes !== undefined;
     if (hasIdle && (typeof idleTimeoutMinutes !== "number" || idleTimeoutMinutes < 0)) {
@@ -60,6 +109,37 @@ export function createBotRouter(
     if (hasAutoPause) config.autoPauseOnEmpty = autoPauseOnEmpty;
     if (hasLocalAudioEnabled) config.localAudioEnabled = localAudioEnabled;
 
+    // Voice ducking is a partial settings block. Merge only known, strictly
+    // valid fields so malformed JSON cannot replace the object or inject NaN /
+    // out-of-range gain values into the live audio path.
+    const hasVoiceDucking =
+      voiceDucking !== null &&
+      typeof voiceDucking === "object" &&
+      !Array.isArray(voiceDucking);
+    if (hasVoiceDucking) {
+      if (typeof voiceDucking.enabled === "boolean") {
+        config.voiceDucking.enabled = voiceDucking.enabled;
+      }
+      if (
+        typeof voiceDucking.volumePercent === "number" &&
+        Number.isFinite(voiceDucking.volumePercent) &&
+        voiceDucking.volumePercent >= 0 &&
+        voiceDucking.volumePercent <= 100
+      ) {
+        config.voiceDucking.volumePercent = voiceDucking.volumePercent;
+      }
+    }
+
+    // Saved-queues + play-keeps-queue toggles (default off). Both read live from
+    // config by BotInstance / the saved-queues router, so no per-bot push needed;
+    // only a literal boolean mutates the stored value (junk is ignored).
+    if (typeof req.body.savedQueuesEnabled === "boolean") {
+      config.savedQueuesEnabled = req.body.savedQueuesEnabled;
+    }
+    if (typeof req.body.playKeepsQueue === "boolean") {
+      config.playKeepsQueue = req.body.playKeepsQueue;
+    }
+
     const hasGuestMode = guestMode !== undefined && guestMode !== null && typeof guestMode === "object";
     if (hasGuestMode) {
       const gm = config.guestMode;
@@ -85,8 +165,103 @@ export function createBotRouter(
       );
     }
 
+    // Partial-merge the spotify block (mirrors config.ts validation). Invalid
+    // sub-fields are ignored rather than 400-ing the whole request. Omitting
+    // `spotify` entirely leaves config.spotify untouched.
+    const VALID_BACKENDS = ["auto", "go-librespot", "librespot"] as const;
+    const VALID_BITRATES = [96, 160, 320];
+    const sp = req.body?.spotify;
+    if (sp && typeof sp === "object") {
+      const t = config.spotify;
+      if (typeof sp.enabled === "boolean") t.enabled = sp.enabled;
+      if (typeof sp.backend === "string" && (VALID_BACKENDS as readonly string[]).includes(sp.backend)) {
+        t.backend = sp.backend as SpotifyConfig["backend"];
+      }
+      if (typeof sp.clientId === "string") t.clientId = sp.clientId;
+      // Secret is write-only + set-on-non-empty so a blank field never wipes it.
+      if (typeof sp.clientSecret === "string" && sp.clientSecret.length > 0) {
+        t.clientSecret = sp.clientSecret;
+      }
+      if (typeof sp.deviceName === "string" && sp.deviceName.trim().length > 0) {
+        t.deviceName = sp.deviceName.trim();
+      }
+      if (typeof sp.bitrate === "number" && VALID_BITRATES.includes(sp.bitrate)) {
+        t.bitrate = sp.bitrate;
+      }
+    }
+
+    // Partial-merge the jellyfin block (same contract as spotify): invalid
+    // sub-fields are ignored; password/apiKey are write-only and only stored
+    // when non-empty so a blank (masked) field never wipes them.
+    const jf = req.body?.jellyfin;
+    if (jf && typeof jf === "object") {
+      const t = config.jellyfin;
+      if (typeof jf.serverUrl === "string") {
+        t.serverUrl = jf.serverUrl.trim().replace(/\/+$/, "");
+      }
+      if (jf.authMode === "userpass" || jf.authMode === "apikey") t.authMode = jf.authMode;
+      if (typeof jf.username === "string") t.username = jf.username;
+      if (typeof jf.password === "string" && jf.password.length > 0) t.password = jf.password;
+      if (typeof jf.apiKey === "string" && jf.apiKey.length > 0) t.apiKey = jf.apiKey;
+      if (typeof jf.userId === "string") t.userId = jf.userId;
+    }
+
+    // enabledProviders: full replace, known providers only (mirrors loadConfig).
+    // An empty array is a valid "all gateable sources off". NOTE: the NetEase/QQ
+    // sidecar API servers are only started at boot, so newly enabling those two
+    // still needs a restart; jellyfin and the rest take effect immediately.
+    const ep = req.body?.enabledProviders;
+    if (Array.isArray(ep)) {
+      config.enabledProviders = ep.filter((p: unknown): p is GateableProvider =>
+        (GATEABLE_PROVIDERS as readonly string[]).includes(p as string),
+      );
+    }
+
+    // defaultPlatform (issue #126): the operator-chosen default source for
+    // platform-less commands/REST/WebUI calls. Reconciled AFTER enabledProviders
+    // so both are validated against the same (possibly updated) enabled list:
+    //   1) Drop a stored default that the new enabledProviders no longer allows,
+    //      keeping the persisted config consistent with loadConfig's invariant.
+    //   2) Apply an explicit change — `null`/`""` clears it (back to priority
+    //      order); a known+enabled provider sets it; anything else is ignored.
+    if (config.defaultPlatform && !config.enabledProviders.includes(config.defaultPlatform)) {
+      config.defaultPlatform = null;
+    }
+    if ("defaultPlatform" in req.body) {
+      const dp = req.body.defaultPlatform;
+      if (dp === null || dp === "") {
+        config.defaultPlatform = null;
+      } else if (
+        typeof dp === "string" &&
+        (GATEABLE_PROVIDERS as readonly string[]).includes(dp) &&
+        config.enabledProviders.includes(dp as GateableProvider)
+      ) {
+        config.defaultPlatform = dp as GateableProvider;
+      }
+    }
+
     saveConfig(configPath, config);
 
+    // Hot-apply the (possibly re-pointed) Jellyfin connection to the live
+    // provider — a Settings save must work without a restart.
+    if (jf && typeof jf === "object") {
+      jellyfinProvider?.configure(config.jellyfin);
+    }
+
+    // I2: only when the spotify block was present, push the (possibly UI-entered)
+    // Client ID into the live process-wide OAuth so Connect works without a
+    // restart. Empty clientId => undefined redirect => configure() disables OAuth.
+    if (sp && typeof sp === "object") {
+      const redirectUri = config.spotify.clientId
+        ? `http://127.0.0.1:${config.webPort}/api/spotify/callback`
+        : undefined;
+      spotifyOAuth?.configure(config.spotify.clientId, redirectUri);
+      // R2-4: also refresh the live Web API search provider so search/getAuthStatus
+      // work without a restart. Uses the post-merge values so a masked/omitted
+      // secret keeps the stored one. The secret is never logged.
+      spotifyProvider?.setCreds(config.spotify.clientId, config.spotify.clientSecret);
+    }
+
     // Guest-mode changed: tear down / re-scope in-flight guest WS sockets so a
     // disabled or narrowed scope takes effect immediately (matches requireAuth's
     // "disabling immediately invalidates in-flight guest sessions" invariant).
@@ -98,14 +273,22 @@ export function createBotRouter(
     for (const bot of botManager.getAllBots()) {
       if (hasIdle) bot.updateIdleTimeout(config.idleTimeoutMinutes);
       if (hasAutoPause) bot.updateAutoPause(config.autoPauseOnEmpty);
+      if (hasVoiceDucking) bot.updateVoiceDucking(config.voiceDucking);
     }
 
     res.json({
       idleTimeoutMinutes: config.idleTimeoutMinutes ?? 0,
       autoPauseOnEmpty: config.autoPauseOnEmpty,
+      voiceDucking: config.voiceDucking,
       localAudioEnabled: config.localAudioEnabled,
+      savedQueuesEnabled: config.savedQueuesEnabled,
+      playKeepsQueue: config.playKeepsQueue,
       adminGroups: config.adminGroups ?? [],
       guestMode: config.guestMode,
+      spotify: maskedSpotify(),
+      jellyfin: maskedJellyfin(),
+      enabledProviders: config.enabledProviders,
+      defaultPlatform: config.defaultPlatform,
     });
   });
 

src/web/api/music.test.ts

@@ -0,0 +1,505 @@
+import { describe, it, expect, vi, beforeEach, afterEach } from "vitest";
+import express from "express";
+import cookieParser from "cookie-parser";
+import request from "supertest";
+import pino from "pino";
+import { mkdtempSync, rmSync, readFileSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import type { MusicProvider, SearchResult } from "../../music/provider.js";
+import { getDefaultConfig, loadConfig, type BotConfig } from "../../data/config.js";
+import { createDatabase, type BotDatabase } from "../../data/database.js";
+import { createUserStore } from "../../data/users.js";
+import { createSessionStore } from "../../data/sessions.js";
+import { createPermissionStore } from "../../data/permissions.js";
+import { createRequireAuth } from "../middleware/requireAuth.js";
+import { SESSION_COOKIE_NAME } from "../auth/validateSession.js";
+import { createMusicRouter, createLocalUploadBody } from "./music.js";
+
+const empty: SearchResult = { songs: [], albums: [], playlists: [] };
+
+function fakeProvider(platform: MusicProvider["platform"]): MusicProvider {
+  return {
+    platform,
+    search: vi.fn().mockResolvedValue(empty),
+  } as unknown as MusicProvider;
+}
+
+describe("music router GET /search offset pagination", () => {
+  let app: express.Express;
+  let netease: MusicProvider;
+
+  beforeEach(() => {
+    netease = fakeProvider("netease");
+    const router = createMusicRouter(
+      netease,
+      fakeProvider("qq"),
+      fakeProvider("bilibili"),
+      pino({ level: "silent" })
+    );
+    app = express();
+    app.use("/api/music", router);
+  });
+
+  it("parses offset and passes it as the 3rd arg to provider.search", async () => {
+    const res = await request(app).get("/api/music/search?q=hello&limit=20&offset=20");
+    expect(res.status).toBe(200);
+    expect(netease.search).toHaveBeenCalledWith("hello", 20, 20);
+  });
+
+  it("defaults a missing offset to 0", async () => {
+    const res = await request(app).get("/api/music/search?q=hello&limit=20");
+    expect(res.status).toBe(200);
+    expect(netease.search).toHaveBeenCalledWith("hello", 20, 0);
+  });
+
+  it("clamps a negative offset to 0", async () => {
+    const res = await request(app).get("/api/music/search?q=hello&limit=20&offset=-5");
+    expect(res.status).toBe(200);
+    expect(netease.search).toHaveBeenCalledWith("hello", 20, 0);
+  });
+});
+
+describe("music router provider gating (enabledProviders) + jellyfin endpoints", () => {
+  function jellyfinFake(): MusicProvider {
+    return {
+      platform: "jellyfin",
+      search: vi.fn().mockResolvedValue(empty),
+      getQuality: vi.fn().mockReturnValue("direct"),
+      getLatestAlbums: vi
+        .fn()
+        .mockResolvedValue([{ id: "a1", name: "Album", platform: "jellyfin" }]),
+      getFavoriteSongs: vi.fn().mockResolvedValue([]),
+    } as unknown as MusicProvider;
+  }
+
+  function mount(config: BotConfig) {
+    const netease = fakeProvider("netease");
+    const jellyfin = jellyfinFake();
+    const router = createMusicRouter(
+      netease,
+      fakeProvider("qq"),
+      fakeProvider("bilibili"),
+      pino({ level: "silent" }),
+      undefined,
+      config,
+      fakeProvider("kugou"),
+      fakeProvider("spotify"),
+      jellyfin,
+    );
+    const app = express();
+    app.use("/api/music", router);
+    return { app, netease, jellyfin };
+  }
+
+  it("routes a platform-less /search to the default platform (netease)", async () => {
+    const { app, netease, jellyfin } = mount(getDefaultConfig());
+    const res = await request(app).get("/api/music/search?q=hello");
+    expect(res.status).toBe(200);
+    expect(netease.search).toHaveBeenCalledWith("hello", 20, 0);
+    expect(jellyfin.search).not.toHaveBeenCalled();
+  });
+
+  it("rejects a disabled platform with 400 without calling its provider", async () => {
+    // Default config leaves jellyfin (opt-in) disabled.
+    const { app, jellyfin } = mount(getDefaultConfig());
+    const res = await request(app).get("/api/music/search?q=hello&platform=jellyfin");
+    expect(res.status).toBe(400);
+    expect(jellyfin.search).not.toHaveBeenCalled();
+  });
+
+  it("allows an explicitly enabled jellyfin platform", async () => {
+    const config = getDefaultConfig();
+    config.enabledProviders = [...config.enabledProviders, "jellyfin"];
+    const { app, jellyfin } = mount(config);
+    const res = await request(app).get("/api/music/search?q=hello&platform=jellyfin");
+    expect(res.status).toBe(200);
+    expect(jellyfin.search).toHaveBeenCalledWith("hello", 20, 0);
+  });
+
+  it("GET /providers reports enabled sources and the default platform", async () => {
+    const { app } = mount(getDefaultConfig());
+    const res = await request(app).get("/api/music/providers");
+    expect(res.status).toBe(200);
+    expect(res.body.default).toBe("netease");
+    expect(res.body.enabled).toContain("netease");
+    expect(res.body.enabled).toContain("local"); // localAudioEnabled defaults on
+    expect(res.body.enabled).not.toContain("jellyfin"); // opt-in, off by default
+    expect(res.body.enabled).not.toContain("spotify"); // spotify.enabled defaults off
+  });
+
+  it("GET /providers reports a configured defaultPlatform override (#126)", async () => {
+    const config = getDefaultConfig();
+    config.defaultPlatform = "qq"; // operator prefers QQ over the priority order
+    const { app } = mount(config);
+    const res = await request(app).get("/api/music/providers");
+    expect(res.status).toBe(200);
+    expect(res.body.default).toBe("qq");
+  });
+
+  it("routes a platform-less /search to the configured defaultPlatform (#126)", async () => {
+    const config = getDefaultConfig();
+    config.defaultPlatform = "bilibili";
+    const { app, netease } = mount(config);
+    const res = await request(app).get("/api/music/search?q=hello");
+    expect(res.status).toBe(200);
+    // Default is now bilibili, so the netease provider must NOT be hit.
+    expect(netease.search).not.toHaveBeenCalled();
+  });
+
+  /** Default config plus the opt-in jellyfin source enabled. */
+  function configWithJellyfin() {
+    const config = getDefaultConfig();
+    config.enabledProviders = [...config.enabledProviders, "jellyfin"];
+    return config;
+  }
+
+  it("GET /jellyfin/latest-albums returns provider data", async () => {
+    const { app, jellyfin } = mount(configWithJellyfin());
+    const res = await request(app).get("/api/music/jellyfin/latest-albums?limit=5");
+    expect(res.status).toBe(200);
+    expect(
+      (jellyfin as unknown as { getLatestAlbums: ReturnType<typeof vi.fn> }).getLatestAlbums,
+    ).toHaveBeenCalledWith(5);
+    expect(res.body.albums).toHaveLength(1);
+  });
+
+  it("GET /jellyfin/latest-albums is 400 when jellyfin is disabled (the default)", async () => {
+    const { app } = mount(getDefaultConfig());
+    const res = await request(app).get("/api/music/jellyfin/latest-albums");
+    expect(res.status).toBe(400);
+  });
+
+  it("GET /jellyfin/favorites denies unauthenticated/guest access", async () => {
+    const { app } = mount(configWithJellyfin());
+    const res = await request(app).get("/api/music/jellyfin/favorites");
+    expect(res.status).toBe(401);
+  });
+});
+
+describe("music router POST /quality — persistence (#125)", () => {
+  let tmpDir: string;
+  let configPath: string;
+  let config: BotConfig;
+  let botDb: BotDatabase;
+  let app: express.Express;
+  let cookie: string;
+  let providers: Record<string, MusicProvider>;
+
+  /** A provider whose in-memory quality is settable and readable, like the real
+   *  ones. */
+  function qualityProvider(platform: MusicProvider["platform"], initial: string): MusicProvider {
+    let q = initial;
+    return {
+      platform,
+      search: vi.fn().mockResolvedValue(empty),
+      getQuality: vi.fn(() => q),
+      setQuality: vi.fn((v: string) => { q = v; }),
+    } as unknown as MusicProvider;
+  }
+
+  /** Jellyfin only accepts its own tiers (mirrors the real provider), so a
+   *  broadcast of a foreign value is ignored — proving the snapshot captures each
+   *  provider's ACTUAL post-apply state, not just the request value. */
+  function jellyfinQualityProvider(): MusicProvider {
+    let q = "direct";
+    const tiers = new Set(["direct", "320", "192", "128"]);
+    return {
+      platform: "jellyfin",
+      search: vi.fn().mockResolvedValue(empty),
+      getQuality: vi.fn(() => q),
+      setQuality: vi.fn((v: string) => { if (tiers.has(v)) q = v; }),
+    } as unknown as MusicProvider;
+  }
+
+  beforeEach(async () => {
+    botDb = createDatabase(":memory:");
+    const users = createUserStore(botDb.db);
+    const sessions = createSessionStore(botDb.db);
+    const admin = await users.createUser("admin", "pw-admin", "admin");
+    cookie = `${SESSION_COOKIE_NAME}=${sessions.createSession(admin.id).token}`;
+
+    tmpDir = mkdtempSync(join(tmpdir(), "musicquality-"));
+    configPath = join(tmpDir, "config.json");
+    config = getDefaultConfig();
+
+    providers = {
+      netease: qualityProvider("netease", "exhigh"),
+      qq: qualityProvider("qq", "exhigh"),
+      bilibili: qualityProvider("bilibili", "high"),
+      kugou: qualityProvider("kugou", "128"),
+      jellyfin: jellyfinQualityProvider(),
+    };
+
+    app = express();
+    app.use(express.json());
+    app.use(cookieParser());
+    app.use("/api", createRequireAuth(sessions, createPermissionStore(botDb.db), () => getDefaultConfig().guestMode));
+    app.use(
+      "/api/music",
+      createMusicRouter(
+        providers.netease, providers.qq, providers.bilibili, pino({ level: "silent" }),
+        undefined, config, providers.kugou, undefined, providers.jellyfin, configPath,
+      ),
+    );
+  });
+
+  afterEach(() => {
+    botDb.close();
+    rmSync(tmpDir, { recursive: true, force: true });
+  });
+
+  it("persists a platform-specific quality change to config.json", async () => {
+    const res = await request(app)
+      .post("/api/music/quality")
+      .set("Cookie", cookie)
+      .send({ platform: "netease", quality: "lossless" });
+    expect(res.status).toBe(200);
+    expect(providers.netease.setQuality).toHaveBeenCalledWith("lossless");
+    // in-memory config mutated
+    expect(config.audioQuality.netease).toBe("lossless");
+    // written to disk + reload reflects it (survives a restart)
+    const onDisk = JSON.parse(readFileSync(configPath, "utf-8"));
+    expect(onDisk.audioQuality.netease).toBe("lossless");
+    expect(loadConfig(configPath).audioQuality.netease).toBe("lossless");
+  });
+
+  it("snapshots each provider's post-apply quality on a broadcast change", async () => {
+    const res = await request(app)
+      .post("/api/music/quality")
+      .set("Cookie", cookie)
+      .send({ quality: "320" });
+    expect(res.status).toBe(200);
+    // Broadcast reached every provider…
+    expect(providers.netease.setQuality).toHaveBeenCalledWith("320");
+    expect(providers.jellyfin.setQuality).toHaveBeenCalledWith("320");
+    // …and the snapshot reflects what each one actually accepted. Jellyfin's
+    // "320" is a valid tier here, so it takes; a foreign value would be ignored.
+    expect(config.audioQuality).toEqual({
+      netease: "320",
+      qq: "320",
+      bilibili: "320",
+      kugou: "320",
+      jellyfin: "320",
+    });
+  });
+
+  it("ignores foreign broadcast values that a provider rejects (jellyfin)", async () => {
+    const res = await request(app)
+      .post("/api/music/quality")
+      .set("Cookie", cookie)
+      .send({ quality: "lossless" });
+    expect(res.status).toBe(200);
+    // jellyfin rejects the NetEase-style value → stays at its default tier.
+    expect(config.audioQuality.jellyfin).toBe("direct");
+    expect(config.audioQuality.netease).toBe("lossless");
+  });
+});
+
+// #149: video containers must survive the transport layer. Before this the
+// express.raw type filter only matched audio/*, video/webm and
+// application/octet-stream, so a browser-sent video/mp4 body was never parsed
+// and the handler answered 400 "raw audio body is required".
+describe("music router POST /local/upload — content types and size cap (#149)", () => {
+  let app: express.Express;
+  let botDb: BotDatabase;
+  let cookie: string;
+  let uploadAudio: ReturnType<typeof vi.fn>;
+
+  beforeEach(async () => {
+    botDb = createDatabase(":memory:");
+    const users = createUserStore(botDb.db);
+    const sessions = createSessionStore(botDb.db);
+    const admin = await users.createUser("admin", "pw-admin", "admin");
+    cookie = `${SESSION_COOKIE_NAME}=${sessions.createSession(admin.id).token}`;
+
+    uploadAudio = vi.fn(async (input: { originalName: string }) => ({
+      id: "local-1", name: input.originalName, artist: "本地上传", album: "本地音乐",
+      duration: 1, coverUrl: "", platform: "local",
+    }));
+    const local = { platform: "local", search: vi.fn().mockResolvedValue(empty), uploadAudio } as unknown as MusicProvider;
+
+    app = express();
+    app.use(express.json());
+    app.use(cookieParser());
+    app.use("/api", createRequireAuth(sessions, createPermissionStore(botDb.db), () => getDefaultConfig().guestMode));
+    app.use("/api/music", createMusicRouter(
+      fakeProvider("netease"), fakeProvider("qq"), fakeProvider("bilibili"),
+      pino({ level: "silent" }), local, getDefaultConfig(),
+    ));
+  });
+
+  afterEach(() => botDb.close());
+
+  const post = (contentType: string, body: Buffer, name = "clip.mp4") =>
+    request(app)
+      .post("/api/music/local/upload")
+      .set("Cookie", cookie)
+      .set("Content-Type", contentType)
+      .set("X-Filename", encodeURIComponent(name))
+      .send(body);
+
+  it("accepts the video MIME types browsers actually send", async () => {
+    // These are what Chrome/Firefox put on a File for .mp4/.mov/.avi/.mkv.
+    for (const ct of ["video/mp4", "video/quicktime", "video/x-msvideo", "video/x-matroska", "video/webm"]) {
+      uploadAudio.mockClear();
+      const res = await post(ct, Buffer.from("fake video bytes"));
+      expect(res.status, `content-type ${ct}`).toBe(200);
+      expect(uploadAudio).toHaveBeenCalledOnce();
+      expect(res.body.song.platform).toBe("local");
+    }
+  });
+
+  it("still accepts audio and octet-stream bodies", async () => {
+    for (const ct of ["audio/mpeg", "audio/flac", "application/octet-stream"]) {
+      uploadAudio.mockClear();
+      const res = await post(ct, Buffer.from("fake audio"), "tune.mp3");
+      expect(res.status, `content-type ${ct}`).toBe(200);
+      expect(uploadAudio).toHaveBeenCalledOnce();
+    }
+  });
+
+  it("passes the decoded filename and the content type through to the provider", async () => {
+    await post("video/mp4", Buffer.from("bytes"), "我的 视频.mp4");
+    expect(uploadAudio).toHaveBeenCalledWith(
+      expect.objectContaining({ originalName: "我的 视频.mp4", mimeType: "video/mp4" }),
+    );
+  });
+
+  it("surfaces a provider rejection as a 400 with its message", async () => {
+    uploadAudio.mockRejectedValueOnce(new Error("这个视频里没有音轨，无法播放"));
+    const res = await post("video/mp4", Buffer.from("bytes"));
+    expect(res.status).toBe(400);
+    expect(res.body.error).toBe("这个视频里没有音轨，无法播放");
+  });
+
+  it("requires authentication", async () => {
+    const res = await request(app)
+      .post("/api/music/local/upload")
+      .set("Content-Type", "video/mp4")
+      .send(Buffer.from("bytes"));
+    expect(res.status).toBe(401);
+  });
+
+  it("rejects an oversize body as JSON, not an HTML stack trace", async () => {
+    // Same middleware the route mounts, built with a small limit so the test
+    // does not have to allocate half a gigabyte to reach the cap.
+    const tiny = express();
+    const reached = vi.fn();
+    tiny.post("/u", createLocalUploadBody("1kb"), (_req, res) => { reached(); res.json({ ok: true }); });
+
+    const res = await request(tiny)
+      .post("/u")
+      .set("Content-Type", "video/mp4")
+      .send(Buffer.alloc(4096, 1));
+
+    expect(res.status).toBe(413);
+    expect(res.headers["content-type"]).toMatch(/application\/json/);
+    expect(res.body.error).toContain("文件太大");
+    // The HTML default handler leaked absolute server paths and a stack.
+    expect(res.text).not.toMatch(/node_modules|<\/pre>|at read/);
+    expect(reached).not.toHaveBeenCalled();
+  });
+
+  it("lets a body under the cap through the same middleware", async () => {
+    const tiny = express();
+    tiny.post("/u", createLocalUploadBody("1kb"), (req, res) => {
+      res.json({ bytes: (req.body as Buffer).length });
+    });
+    const res = await request(tiny)
+      .post("/u")
+      .set("Content-Type", "video/mp4")
+      .send(Buffer.alloc(512, 1));
+    expect(res.status).toBe(200);
+    expect(res.body.bytes).toBe(512);
+  });
+
+  it("rejects local uploads when the feature is switched off", async () => {
+    const off = getDefaultConfig();
+    off.localAudioEnabled = false;
+    const users = createUserStore(botDb.db);
+    const sessions = createSessionStore(botDb.db);
+    const a2 = await users.createUser("admin2", "pw-admin2", "admin");
+    const c2 = `${SESSION_COOKIE_NAME}=${sessions.createSession(a2.id).token}`;
+    const app2 = express();
+    app2.use(cookieParser());
+    app2.use("/api", createRequireAuth(sessions, createPermissionStore(botDb.db), () => getDefaultConfig().guestMode));
+    app2.use("/api/music", createMusicRouter(
+      fakeProvider("netease"), fakeProvider("qq"), fakeProvider("bilibili"),
+      pino({ level: "silent" }),
+      { platform: "local", search: vi.fn(), uploadAudio } as unknown as MusicProvider, off,
+    ));
+    const res = await request(app2)
+      .post("/api/music/local/upload")
+      .set("Cookie", c2)
+      .set("Content-Type", "video/mp4")
+      .send(Buffer.from("bytes"));
+    expect(res.status).toBe(403);
+    expect(uploadAudio).not.toHaveBeenCalled();
+  });
+});
+
+describe("music router GET /bilibili/parts", () => {
+  it("returns 400 when bvid is missing", async () => {
+    const router = createMusicRouter(
+      fakeProvider("netease"),
+      fakeProvider("qq"),
+      fakeProvider("bilibili"),
+      pino({ level: "silent" })
+    );
+    const app = express();
+    app.use("/api/music", router);
+
+    const res = await request(app).get("/api/music/bilibili/parts");
+    expect(res.status).toBe(400);
+    expect(res.body.error).toBe("bvid is required");
+  });
+
+  it("returns parts from bilibili provider when available", async () => {
+    const mockBilibili = {
+      platform: "bilibili" as const,
+      search: vi.fn(),
+      getVideoParts: vi.fn().mockResolvedValue({
+        bvid: "BV1test",
+        title: "多P视频测试",
+        parts: [
+          { part: 1, cid: 101, title: "P1", duration: 100 },
+          { part: 2, cid: 102, title: "P2", duration: 200 },
+        ],
+      }),
+    };
+    const router = createMusicRouter(
+      fakeProvider("netease"),
+      fakeProvider("qq"),
+      mockBilibili as unknown as MusicProvider,
+      pino({ level: "silent" })
+    );
+    const app = express();
+    app.use("/api/music", router);
+
+    const res = await request(app).get("/api/music/bilibili/parts?bvid=BV1test");
+    expect(res.status).toBe(200);
+    expect(res.body.bvid).toBe("BV1test");
+    expect(res.body.parts).toHaveLength(2);
+    expect(mockBilibili.getVideoParts).toHaveBeenCalledWith("BV1test");
+  });
+
+  it("returns 404 when getVideoParts returns null", async () => {
+    const mockBilibili = {
+      platform: "bilibili" as const,
+      search: vi.fn(),
+      getVideoParts: vi.fn().mockResolvedValue(null),
+    };
+    const router = createMusicRouter(
+      fakeProvider("netease"),
+      fakeProvider("qq"),
+      mockBilibili as unknown as MusicProvider,
+      pino({ level: "silent" })
+    );
+    const app = express();
+    app.use("/api/music", router);
+
+    const res = await request(app).get("/api/music/bilibili/parts?bvid=BV1notfound");
+    expect(res.status).toBe(404);
+  });
+});

src/web/api/music.ts

@@ -1,19 +1,75 @@
-import express, { Router } from "express";
-import type { MusicProvider } from "../../music/provider.js";
+import express, { Router, type Response } from "express";
+import type { MusicProvider, Song, Album } from "../../music/provider.js";
 import { YouTubeProvider } from "../../music/youtube.js";
 import type { Logger } from "../../logger.js";
-import type { BotConfig } from "../../data/config.js";
+import { isProviderEnabled, defaultPlatform, saveConfig, type BotConfig } from "../../data/config.js";
 import { requirePermission } from "../middleware/requirePermission.js";
 import { requireNotGuest } from "../middleware/requireNotGuest.js";
 import { authorize } from "../middleware/authorize.js";
 
+/**
+ * Body cap for a local upload. express.raw buffers the whole body in memory,
+ * so this is also the peak RAM one upload can cost — raised from 200mb for
+ * video (#149), which is far bigger than audio for the same song, but kept
+ * well short of "any video file at all" for that reason. Only the audio track
+ * survives to disk.
+ */
+export const LOCAL_UPLOAD_LIMIT = "500mb";
+
+/**
+ * Body parser for the local-upload route.
+ *
+ * `type` includes "video/*" (#149): the browser sends the File's own MIME
+ * type, so an .mp4 arrives as video/mp4 and used to be rejected by this
+ * filter before ever reaching the provider. Only the audio track is kept —
+ * uploadAudio remuxes it out on the way in.
+ *
+ * express.raw hands an oversize body to the default error handler, which
+ * answers with an HTML page carrying a stack trace and absolute server paths
+ * (unless NODE_ENV=production, which this project never sets). Video makes
+ * hitting the cap far more likely than audio did, so that one case is
+ * translated into the same JSON shape the rest of this route returns. Any
+ * other body-parser error is passed on untouched.
+ *
+ * Exported as a factory so tests can drive the identical path with a small
+ * limit instead of allocating half a gigabyte.
+ */
+export function createLocalUploadBody(limit: string): express.RequestHandler {
+  const raw = express.raw({
+    type: ["audio/*", "video/*", "application/octet-stream"],
+    limit,
+  });
+  return (req, res, next) => {
+    raw(req, res, (err?: unknown) => {
+      if (!err) {
+        next();
+        return;
+      }
+      const e = err as { type?: string; status?: number };
+      if (e?.type === "entity.too.large" || e?.status === 413) {
+        res.status(413).json({ error: `文件太大，单个文件上限 ${limit}` });
+        return;
+      }
+      next(err);
+    });
+  };
+}
+
+const localUploadBody = createLocalUploadBody(LOCAL_UPLOAD_LIMIT);
+
 export function createMusicRouter(
   neteaseProvider: MusicProvider,
   qqProvider: MusicProvider,
   bilibiliProvider: MusicProvider,
   logger: Logger,
   localProvider?: MusicProvider,
-  config?: BotConfig
+  config?: BotConfig,
+  kugouProvider?: MusicProvider,
+  spotifyProvider?: MusicProvider,
+  jellyfinProvider?: MusicProvider,
+  // When set (alongside config), a quality change is persisted to config.json so
+  // it survives a restart (#125). Omitted by unit-test routers → no persistence.
+  configPath?: string,
 ): Router {
   const router = Router();
   const youtubeProvider: MusicProvider = new YouTubeProvider();
@@ -26,9 +82,29 @@ export function createMusicRouter(
     if (platform === "bilibili") return bilibiliProvider;
     if (platform === "youtube") return youtubeProvider;
     if (platform === "local" && localProvider) return localProvider;
+    if (platform === "kugou" && kugouProvider) return kugouProvider;
+    if (platform === "spotify" && spotifyProvider) return spotifyProvider;
+    if (platform === "jellyfin" && jellyfinProvider) return jellyfinProvider;
     return platform === "qq" ? qqProvider : neteaseProvider;
   }
 
+  /**
+   * Provider gating for user-supplied platform params. No platform → the
+   * configured default (see defaultPlatform(); netease in the default config).
+   * A disabled platform gets a friendly 400 and null back — the handler must
+   * return immediately. Without a config (unit-test routers), everything
+   * stays enabled.
+   */
+  function resolveProvider(platform: unknown, res: Response): MusicProvider | null {
+    const requested = typeof platform === "string" && platform ? platform : undefined;
+    const target = requested ?? (config ? defaultPlatform(config) : "netease");
+    if (config && !isProviderEnabled(config, target)) {
+      res.status(400).json({ error: `音源未启用：${target} (provider disabled)` });
+      return null;
+    }
+    return getProvider(target);
+  }
+
   router.post(
     "/local/upload",
     authorize({ capability: "player.queue", guestFlag: "addToQueue" }),
@@ -39,10 +115,7 @@ export function createMusicRouter(
       }
       next();
     },
-    express.raw({
-      type: ["audio/*", "video/webm", "application/octet-stream"],
-      limit: "200mb",
-    }),
+    localUploadBody,
     async (req, res) => {
       try {
         if (!localProvider) {
@@ -82,7 +155,7 @@ export function createMusicRouter(
 
   router.get("/search", async (req, res) => {
     try {
-      const { q, platform, limit } = req.query;
+      const { q, platform, limit, offset } = req.query;
       if (!q) {
         res.status(400).json({ error: "q (query) is required" });
         return;
@@ -91,10 +164,15 @@ export function createMusicRouter(
         res.json({ songs: [], playlists: [], albums: [] });
         return;
       }
-      const provider = getProvider(platform as string);
+      const provider = resolveProvider(platform, res);
+      if (!provider) return;
+      // Server-side pagination: offset lets the web load past the first page.
+      // Clamp to >= 0 so a bad/negative value falls back to the first page.
+      const parsedOffset = Math.max(0, parseInt(offset as string) || 0);
       const result = await provider.search(
         q as string,
-        parseInt(limit as string) || 20
+        parseInt(limit as string) || 20,
+        parsedOffset
       );
       res.json(result);
     } catch (err) {
@@ -111,24 +189,40 @@ export function createMusicRouter(
         return;
       }
       const parsedLimit = parseInt(limit as string) || 20;
-      const [neteaseResult, qqResult, bilibiliResult, localResult] = await Promise.allSettled([
-        neteaseProvider.search(q as string, parsedLimit),
-        qqProvider.search(q as string, parsedLimit),
-        bilibiliProvider.search(q as string, parsedLimit),
-        localProvider && isLocalAudioEnabled() ? localProvider.search(q as string, parsedLimit) : Promise.resolve({ songs: [], albums: [], playlists: [] }),
+      // Spotify is intentionally EXCLUDED from unified /search/all in Stage 1:
+      // its tracks are metadata-only (not yet playable) until the librespot audio
+      // backend lands (Stage 2/3), so surfacing them in the default all-sources
+      // view would only yield results that get skipped. Spotify search remains
+      // available from its own tab via /search?platform=spotify.
+      // Provider gating (#enabledProviders): disabled sources are skipped, not
+      // searched. Jellyfin (an opt-in source) leads the merged results when
+      // enabled — a self-hosted library match is almost always the wanted one.
+      const enabled = (p: string) => !config || isProviderEnabled(config, p);
+      const none = { songs: [], albums: [], playlists: [] };
+      const [jellyfinResult, neteaseResult, qqResult, bilibiliResult, localResult, kugouResult] = await Promise.allSettled([
+        jellyfinProvider && enabled("jellyfin") ? jellyfinProvider.search(q as string, parsedLimit) : Promise.resolve(none),
+        enabled("netease") ? neteaseProvider.search(q as string, parsedLimit) : Promise.resolve(none),
+        enabled("qq") ? qqProvider.search(q as string, parsedLimit) : Promise.resolve(none),
+        enabled("bilibili") ? bilibiliProvider.search(q as string, parsedLimit) : Promise.resolve(none),
+        localProvider && isLocalAudioEnabled() ? localProvider.search(q as string, parsedLimit) : Promise.resolve(none),
+        kugouProvider && enabled("kugou") ? kugouProvider.search(q as string, parsedLimit) : Promise.resolve(none),
       ]);
 
       const songs = [
+        ...(jellyfinResult.status === "fulfilled" ? jellyfinResult.value.songs : []),
         ...(neteaseResult.status === "fulfilled" ? neteaseResult.value.songs : []),
         ...(qqResult.status === "fulfilled" ? qqResult.value.songs : []),
         ...(bilibiliResult.status === "fulfilled" ? bilibiliResult.value.songs : []),
         ...(localResult.status === "fulfilled" ? localResult.value.songs : []),
+        ...(kugouResult.status === "fulfilled" ? kugouResult.value.songs : []),
       ];
       const albums = [
+        ...(jellyfinResult.status === "fulfilled" ? jellyfinResult.value.albums : []),
         ...(neteaseResult.status === "fulfilled" ? neteaseResult.value.albums : []),
         ...(qqResult.status === "fulfilled" ? qqResult.value.albums : []),
       ];
       const playlists = [
+        ...(jellyfinResult.status === "fulfilled" ? jellyfinResult.value.playlists : []),
         ...(neteaseResult.status === "fulfilled" ? neteaseResult.value.playlists : []),
         ...(qqResult.status === "fulfilled" ? qqResult.value.playlists : []),
       ];
@@ -146,7 +240,8 @@ export function createMusicRouter(
         res.status(403).json({ error: "本地音频播放已关闭" });
         return;
       }
-      const provider = getProvider(req.query.platform as string);
+      const provider = resolveProvider(req.query.platform, res);
+      if (!provider) return;
       const song = await provider.getSongDetail(req.params.id);
       if (!song) {
         res.status(404).json({ error: "Song not found" });
@@ -160,7 +255,8 @@ export function createMusicRouter(
 
   router.get("/playlist/:id", async (req, res) => {
     try {
-      const provider = getProvider(req.query.platform as string);
+      const provider = resolveProvider(req.query.platform, res);
+      if (!provider) return;
       const songs = await provider.getPlaylistSongs(req.params.id);
       res.json({ songs });
     } catch (err) {
@@ -170,7 +266,8 @@ export function createMusicRouter(
 
   router.get("/recommend/playlists", async (req, res) => {
     try {
-      const provider = getProvider(req.query.platform as string);
+      const provider = resolveProvider(req.query.platform, res);
+      if (!provider) return;
       const playlists = await provider.getRecommendPlaylists();
       res.json({ playlists });
     } catch (err) {
@@ -180,7 +277,8 @@ export function createMusicRouter(
 
   router.get("/album/:id", async (req, res) => {
     try {
-      const provider = getProvider(req.query.platform as string);
+      const provider = resolveProvider(req.query.platform, res);
+      if (!provider) return;
       const songs = await provider.getAlbumSongs(req.params.id);
       res.json({ songs });
     } catch (err) {
@@ -190,7 +288,8 @@ export function createMusicRouter(
 
   router.get("/lyrics/:id", async (req, res) => {
     try {
-      const provider = getProvider(req.query.platform as string);
+      const provider = resolveProvider(req.query.platform, res);
+      if (!provider) return;
       const lyrics = await provider.getLyrics(req.params.id);
       res.json({ lyrics });
     } catch (err) {
@@ -200,7 +299,8 @@ export function createMusicRouter(
 
   router.get("/recommend/songs", requireNotGuest, async (req, res) => {
     try {
-      const provider = getProvider(req.query.platform as string);
+      const provider = resolveProvider(req.query.platform, res);
+      if (!provider) return;
       if (!provider.getDailyRecommendSongs) {
         res.status(501).json({ error: "Not supported by this provider" });
         return;
@@ -215,7 +315,8 @@ export function createMusicRouter(
 
   router.get("/personal/fm", requireNotGuest, async (req, res) => {
     try {
-      const provider = getProvider(req.query.platform as string);
+      const provider = resolveProvider(req.query.platform, res);
+      if (!provider) return;
       if (!provider.getPersonalFm) {
         res.status(501).json({ error: "Not supported by this provider" });
         return;
@@ -230,7 +331,8 @@ export function createMusicRouter(
 
   router.get("/user/playlists", requireNotGuest, async (req, res) => {
     try {
-      const provider = getProvider(req.query.platform as string);
+      const provider = resolveProvider(req.query.platform, res);
+      if (!provider) return;
       if (!provider.getUserPlaylists) {
         res.status(501).json({ error: "Not supported by this provider" });
         return;
@@ -245,7 +347,8 @@ export function createMusicRouter(
 
   router.get("/playlist/:id/detail", async (req, res) => {
     try {
-      const provider = getProvider(req.query.platform as string);
+      const provider = resolveProvider(req.query.platform, res);
+      if (!provider) return;
       if (!provider.getPlaylistDetail) {
         res.status(501).json({ error: "Not supported by this provider" });
         return;
@@ -279,6 +382,139 @@ export function createMusicRouter(
     }
   });
 
+  // B站分P列表查询
+  router.get("/bilibili/parts", async (req, res) => {
+    try {
+      const bvid = (req.query.bvid as string)?.trim();
+      if (!bvid) {
+        res.status(400).json({ error: "bvid is required" });
+        return;
+      }
+      const provider = bilibiliProvider as any;
+      if (typeof provider.getVideoParts === "function") {
+        const result = await provider.getVideoParts(bvid);
+        if (!result) {
+          res.status(404).json({ error: "Video not found" });
+          return;
+        }
+        res.json(result);
+      } else {
+        res.status(501).json({ error: "Not supported" });
+      }
+    } catch (err) {
+      logger.error({ err }, "Get bilibili parts failed");
+      res.status(500).json({ error: (err as Error).message });
+    }
+  });
+
+  // Enabled sources + default platform, for the web UI (source tabs, default
+  // search/playback source). Without a config (unit-test routers) everything
+  // reports enabled with the legacy netease default.
+  router.get("/providers", (_req, res) => {
+    const ALL_PLATFORMS = [
+      "jellyfin",
+      "netease",
+      "qq",
+      "bilibili",
+      "youtube",
+      "kugou",
+      "spotify",
+      "local",
+    ];
+    res.json({
+      enabled: config ? ALL_PLATFORMS.filter((p) => isProviderEnabled(config, p)) : ALL_PLATFORMS,
+      default: config ? defaultPlatform(config) : "netease",
+    });
+  });
+
+  // ─── Jellyfin home-page data ───────────────────────────────────────────
+  // The concrete JellyfinProvider surface these endpoints consume; the router
+  // only knows the MusicProvider interface, so narrow structurally (same
+  // pattern as localProvider.uploadAudio above).
+  type JellyfinHomeProvider = MusicProvider & {
+    getLatestAlbums?: (limit?: number) => Promise<Album[]>;
+    getMostPlayed?: (limit?: number) => Promise<Song[]>;
+    getFavoriteSongs?: (limit?: number) => Promise<Song[]>;
+    getGenres?: (limit?: number) => Promise<{ id: string; name: string }[]>;
+    getGenreSongs?: (genreId: string, limit?: number) => Promise<Song[]>;
+  };
+  const jellyfinHome = jellyfinProvider as JellyfinHomeProvider | undefined;
+
+  /** 501 when no provider is wired, 400 when the source is disabled. */
+  function jellyfinOrReject(res: Response): JellyfinHomeProvider | null {
+    if (!jellyfinHome) {
+      res.status(501).json({ error: "Jellyfin provider not configured" });
+      return null;
+    }
+    if (config && !isProviderEnabled(config, "jellyfin")) {
+      res.status(400).json({ error: "音源未启用：jellyfin (provider disabled)" });
+      return null;
+    }
+    return jellyfinHome;
+  }
+
+  router.get("/jellyfin/latest-albums", async (req, res) => {
+    try {
+      const p = jellyfinOrReject(res);
+      if (!p) return;
+      const limit = parseInt(req.query.limit as string) || 12;
+      res.json({ albums: (await p.getLatestAlbums?.(limit)) ?? [] });
+    } catch (err) {
+      logger.error({ err }, "Jellyfin latest albums failed");
+      res.status(500).json({ error: (err as Error).message });
+    }
+  });
+
+  router.get("/jellyfin/most-played", async (req, res) => {
+    try {
+      const p = jellyfinOrReject(res);
+      if (!p) return;
+      const limit = parseInt(req.query.limit as string) || 12;
+      res.json({ songs: (await p.getMostPlayed?.(limit)) ?? [] });
+    } catch (err) {
+      logger.error({ err }, "Jellyfin most played failed");
+      res.status(500).json({ error: (err as Error).message });
+    }
+  });
+
+  // Favorites are account-level data — guests don't get them (matches the
+  // requireNotGuest gate on /user/playlists).
+  router.get("/jellyfin/favorites", requireNotGuest, async (req, res) => {
+    try {
+      const p = jellyfinOrReject(res);
+      if (!p) return;
+      const limit = parseInt(req.query.limit as string) || 100;
+      res.json({ songs: (await p.getFavoriteSongs?.(limit)) ?? [] });
+    } catch (err) {
+      logger.error({ err }, "Jellyfin favorites failed");
+      res.status(500).json({ error: (err as Error).message });
+    }
+  });
+
+  router.get("/jellyfin/genres", async (req, res) => {
+    try {
+      const p = jellyfinOrReject(res);
+      if (!p) return;
+      const limit = parseInt(req.query.limit as string) || 30;
+      res.json({ genres: (await p.getGenres?.(limit)) ?? [] });
+    } catch (err) {
+      logger.error({ err }, "Jellyfin genres failed");
+      res.status(500).json({ error: (err as Error).message });
+    }
+  });
+
+  router.get("/jellyfin/genre/:id/songs", async (req, res) => {
+    try {
+      const p = jellyfinOrReject(res);
+      if (!p) return;
+      const limit = parseInt(req.query.limit as string) || 100;
+      res.json({ songs: (await p.getGenreSongs?.(req.params.id, limit)) ?? [] });
+    } catch (err) {
+      logger.error({ err }, "Jellyfin genre songs failed");
+      res.status(500).json({ error: (err as Error).message });
+    }
+  });
+
   // Get current quality
   router.get("/quality", requireNotGuest, (_req, res) => {
     res.json({
@@ -286,6 +522,9 @@ export function createMusicRouter(
       qq: qqProvider.getQuality(),
       bilibili: bilibiliProvider.getQuality(),
       local: localProvider?.getQuality() ?? "original",
+      kugou: kugouProvider?.getQuality() ?? "128",
+      spotify: spotifyProvider?.getQuality() ?? "320",
+      jellyfin: jellyfinProvider?.getQuality() ?? "direct",
     });
   });
 
@@ -305,6 +544,37 @@ export function createMusicRouter(
     if (!platform || platform === "bilibili") {
       bilibiliProvider.setQuality(quality);
     }
+    if ((!platform || platform === "kugou") && kugouProvider) {
+      kugouProvider.setQuality(quality);
+    }
+    if ((!platform || platform === "spotify") && spotifyProvider) {
+      spotifyProvider.setQuality(quality);
+    }
+    // Safe in the platform-less broadcast: JellyfinProvider.setQuality ignores
+    // values outside its own tier list (direct/320/192/128).
+    if ((!platform || platform === "jellyfin") && jellyfinProvider) {
+      jellyfinProvider.setQuality(quality);
+    }
+
+    // Persist the (post-apply) per-provider quality so it survives a restart
+    // (#125). Snapshotting each provider's getQuality() AFTER setQuality captures
+    // exactly what each one accepted (jellyfin ignores foreign tiers, kugou maps
+    // aliases), so replaying these on startup reproduces this state faithfully.
+    if (config && configPath) {
+      config.audioQuality = {
+        netease: neteaseProvider.getQuality(),
+        qq: qqProvider.getQuality(),
+        bilibili: bilibiliProvider.getQuality(),
+        kugou: kugouProvider?.getQuality() ?? config.audioQuality.kugou,
+        jellyfin: jellyfinProvider?.getQuality() ?? config.audioQuality.jellyfin,
+      };
+      try {
+        saveConfig(configPath, config);
+      } catch (err) {
+        logger.warn({ err }, "Failed to persist audio quality");
+      }
+    }
+
     logger.info({ quality, platform }, "Audio quality changed");
     res.json({ success: true, quality });
   });

src/web/api/player.ts

@@ -39,6 +39,11 @@ export function createPlayerRouter(
     if (platform === "bilibili") return "-b";
     if (platform === "qq") return "-q";
     if (platform === "youtube") return "-y";
+    if (platform === "kugou") return "-k";
+    if (platform === "jellyfin") return "-j";
+    // The flag-less default is now the configured default platform (jellyfin
+    // unless disabled), so netease needs an explicit flag.
+    if (platform === "netease") return "-n";
     return "";
   };
 
@@ -52,6 +57,11 @@ export function createPlayerRouter(
     res.status(403).json({ error: "本地音频播放已关闭" });
   }
 
+  function requesterName(req: any): string {
+    const name = req.user?.username;
+    return typeof name === "string" && name.trim() ? name.trim() : "游客";
+  }
+
   router.post("/:botId/play", authorize({ capability: "player.control" }), async (req, res) => {
     try {
       const bot = (req as any).bot;
@@ -65,7 +75,7 @@ export function createPlayerRouter(
         res.status(400).json({ error: "Invalid command" });
         return;
       }
-      const response = await bot.executeCommand(cmd);
+      const response = await bot.executeCommand(cmd, undefined, requesterName(req));
       res.json({ message: response });
     } catch (err) {
       res.status(500).json({ error: (err as Error).message });
@@ -81,7 +91,7 @@ export function createPlayerRouter(
         res.status(400).json({ error: "Invalid command" });
         return;
       }
-      const response = await bot.executeCommand(cmd);
+      const response = await bot.executeCommand(cmd, undefined, requesterName(req));
       res.json({ message: response });
     } catch (err) {
       res.status(500).json({ error: (err as Error).message });
@@ -115,11 +125,11 @@ export function createPlayerRouter(
         return;
       }
       const provider = bot.getProviderFor(
-        platform === "bilibili" || platform === "qq" || platform === "youtube" || platform === "local"
+        platform === "bilibili" || platform === "qq" || platform === "youtube" || platform === "local" || platform === "kugou" || platform === "jellyfin"
           ? platform
           : "netease"
       );
-      const message = await bot.startFm(provider);
+      const message = await bot.startFm(provider, requesterName(req));
       res.json({
         ok:
           !message.startsWith("No FM songs") &&
@@ -197,7 +207,7 @@ export function createPlayerRouter(
           .json({ error: "position must be a finite non-negative number" });
         return;
       }
-      bot.getPlayer().seek(position);
+      bot.seek(position);
       res.json({ message: `Seeked to ${Math.floor(position)}s`, seekOffset: position });
     } catch (err) {
       res.status(500).json({ error: (err as Error).message });
@@ -270,7 +280,7 @@ export function createPlayerRouter(
         `!playlist ${platformFlag(platform)} ${playlistId}`.trim(),
         "!"
       )!;
-      const response = await bot.executeCommand(cmd);
+      const response = await bot.executeCommand(cmd, undefined, requesterName(req));
       res.json({ message: response });
     } catch (err) {
       res.status(500).json({ error: (err as Error).message });
@@ -290,7 +300,7 @@ export function createPlayerRouter(
       // Use the bot's own provider lookup — it already knows about youtube,
       // which the router's constructor params did not.
       const provider = bot.getProviderFor(
-        platform === "bilibili" || platform === "qq" || platform === "youtube" || platform === "local"
+        platform === "bilibili" || platform === "qq" || platform === "youtube" || platform === "local" || platform === "kugou" || platform === "jellyfin"
           ? platform
           : "netease"
       );
@@ -331,7 +341,7 @@ export function createPlayerRouter(
       const queue = bot.getQueueManager();
       queue.clear();
       for (const song of queueable) {
-        queue.add({ ...song, platform: provider.platform });
+        queue.add({ ...song, platform: provider.platform, requestedBy: requesterName(req) });
       }
       // Sweep AFTER the queue is rebuilt: the previous queue's local uploads are
       // released and deleted, but an empty/failed playlist (early return above)
@@ -383,7 +393,7 @@ export function createPlayerRouter(
         return;
       }
       const provider = bot.getProviderFor(
-        platform === "bilibili" || platform === "qq" || platform === "youtube" || platform === "local"
+        platform === "bilibili" || platform === "qq" || platform === "youtube" || platform === "local" || platform === "kugou" || platform === "jellyfin"
           ? platform
           : "netease"
       );
@@ -417,7 +427,7 @@ export function createPlayerRouter(
       const queue = bot.getQueueManager();
       queue.clear();
       for (const song of queueable) {
-        queue.add({ ...song, platform: provider.platform });
+        queue.add({ ...song, platform: provider.platform, requestedBy: requesterName(req) });
       }
       // Sweep AFTER the queue is rebuilt (see play-playlist).
       bot.cleanupQueuedLocalSongs?.("queue_replaced");
@@ -451,7 +461,11 @@ export function createPlayerRouter(
     }
   });
 
-  // Play a single song by ID — resolves URL on demand
+  // Play a single song by ID — resolves URL on demand. Funnels through
+  // bot.playSingleSong so the config.playKeepsQueue decision (clear-and-play vs
+  // insert-and-jump, keeping the queue) lives in one place shared with chat
+  // !play. Serialized via runExclusive like /play-now-song so concurrent
+  // requests can't interleave the queue mutation + playback (#119).
   router.post("/:botId/play-song", authorize({ capability: "player.control" }), async (req, res) => {
     try {
       const bot = (req as any).bot;
@@ -464,23 +478,16 @@ export function createPlayerRouter(
         rejectDisabledLocalAudio(res);
         return;
       }
-      const queue = bot.getQueueManager();
-      bot.getPlayer().stop();
-      queue.clear();
-      queue.add(song);
-      queue.play();
-
-      bot.getPlayer().resetFailures();
-      const ok = await bot.resolveAndPlay(queue.current()!);
-      // Sweep AFTER the new song is queued+resolved, so replaying a local song
-      // that was still in the queue doesn't delete the file we're about to play.
-      bot.cleanupQueuedLocalSongs?.("queue_replaced");
-      if (!ok) {
-        res.json({ ok: false, message: `无法播放「${song.name || song.id}」（区域/版权限制）` });
-        return;
-      }
-
-      res.json({ ok: true, message: `正在播放：${song.name || 'Unknown'} - ${song.artist || 'Unknown'}` });
+      // The cleanupQueuedLocalSongs sweep now lives inside playSingleSong's
+      // clear branch — do NOT also call it here, or it would delete retained
+      // local uploads in keep-queue mode.
+      const body = await bot.runExclusive(async () => {
+        const ok = await bot.playSingleSong({ ...song }, requesterName(req));
+        return ok
+          ? { ok: true, message: `正在播放：${song.name || 'Unknown'} - ${song.artist || 'Unknown'}` }
+          : { ok: false, message: `无法播放「${song.name || song.id}」（区域/版权限制）` };
+      });
+      res.json(body);
     } catch (err) {
       res.status(500).json({ error: (err as Error).message });
     }
@@ -512,7 +519,7 @@ export function createPlayerRouter(
         // after natural track end without queue.clear()).
         const insertedAt =
           queue.getCurrentIndex() < 0 ? queue.size() : queue.getCurrentIndex() + 1;
-        queue.addNext(song);
+        queue.addNext({ ...song, requestedBy: requesterName(req) });
 
         if (wasIdle) {
           // Promote the just-added song to current and start it.
@@ -554,7 +561,7 @@ export function createPlayerRouter(
         const queue = bot.getQueueManager();
         const insertedAt =
           queue.getCurrentIndex() < 0 ? queue.size() : queue.getCurrentIndex() + 1;
-        queue.addNext(song);
+        queue.addNext({ ...song, requestedBy: requesterName(req) });
         queue.playAt(insertedAt);
         bot.getPlayer().resetFailures();
         const ok = await bot.resolveAndPlay(queue.current()!);
@@ -586,7 +593,7 @@ export function createPlayerRouter(
       const body = await bot.runExclusive(async () => {
         const queue = bot.getQueueManager();
         const wasIdle = bot.getPlayer().getState() === "idle";
-        queue.add(song);
+        queue.add({ ...song, requestedBy: requesterName(req) });
 
         // If nothing was playing, start this newly-added song immediately.
         if (wasIdle) {
@@ -614,7 +621,7 @@ export function createPlayerRouter(
         return;
       }
       const provider = bot.getProviderFor(
-        platform === "bilibili" || platform === "qq" || platform === "youtube" || platform === "local"
+        platform === "bilibili" || platform === "qq" || platform === "youtube" || platform === "local" || platform === "kugou" || platform === "jellyfin"
           ? platform
           : "netease"
       );
@@ -626,7 +633,7 @@ export function createPlayerRouter(
       }
 
       const queue = bot.getQueueManager();
-      queue.add({ ...song, platform: provider.platform });
+      queue.add({ ...song, platform: provider.platform, requestedBy: requesterName(req) });
 
       // If nothing is playing, start the first song
       if (bot.getPlayer().getState() === "idle") {
@@ -677,6 +684,7 @@ export function createPlayerRouter(
       coverUrl: r.coverUrl,
       platform: r.platform,
       playedAt: r.playedAt,
+      requestedBy: r.requestedBy,
     }));
     res.json({ history });
   });

src/web/api/saved-queues.test.ts

@@ -0,0 +1,119 @@
+import { describe, it, expect } from "vitest";
+import express from "express";
+import request from "supertest";
+import pino from "pino";
+import { createDatabase, SHARED_QUEUE_OWNER, type BotDatabase } from "../../data/database.js";
+import type { BotManager } from "../../bot/manager.js";
+import { createSavedQueuesRouter } from "./saved-queues.js";
+
+const song = (id: string) => ({
+  id,
+  name: id,
+  artist: "",
+  album: "",
+  platform: "netease" as const,
+  coverUrl: "",
+  duration: 1,
+});
+
+function mount(enabled: boolean, opts: { queue?: unknown[] } = {}) {
+  const db = createDatabase(":memory:");
+  const loads: Array<{ songs: unknown[]; mode: string; by?: string }> = [];
+  const bot = {
+    getQueueManager: () => ({ list: () => opts.queue ?? [song("a"), song("b")] }),
+    loadSavedQueue: async (songs: unknown[], mode: string, by?: string) => {
+      loads.push({ songs, mode, by });
+    },
+  };
+  const botManager = { getBot: (_id: string) => bot } as unknown as BotManager;
+  const app = express();
+  app.use(express.json());
+  app.use((req, _res, next) => {
+    (req as unknown as { user: unknown }).user = { id: "u1", username: "alice", role: "member" };
+    next();
+  });
+  app.use(
+    "/api/saved-queues",
+    createSavedQueuesRouter(db, botManager, () => enabled, pino({ level: "silent" })),
+  );
+  return { app, db, loads };
+}
+
+describe("saved-queues router", () => {
+  it("403s every route when the feature is disabled", async () => {
+    const { app } = mount(false);
+    expect((await request(app).get("/api/saved-queues")).status).toBe(403);
+    expect((await request(app).post("/api/saved-queues").send({ botId: "b", name: "x" })).status).toBe(403);
+    expect((await request(app).post("/api/saved-queues/1/load").send({ botId: "b" })).status).toBe(403);
+    expect((await request(app).delete("/api/saved-queues/1")).status).toBe(403);
+  });
+
+  it("saves the current queue (private) and lists it back", async () => {
+    const { app } = mount(true);
+    const save = await request(app).post("/api/saved-queues").send({ botId: "b", name: "night" });
+    expect(save.status).toBe(200);
+    expect(save.body.queue.name).toBe("night");
+    expect(save.body.queue.songCount).toBe(2);
+    expect(save.body.queue.ownerId).toBe("u1");
+
+    const list = await request(app).get("/api/saved-queues");
+    expect(list.status).toBe(200);
+    expect(list.body.queues.map((q: { name: string }) => q.name)).toContain("night");
+  });
+
+  it("saves to the shared bucket when shared:true", async () => {
+    const { app, db } = mount(true);
+    const save = await request(app).post("/api/saved-queues").send({ botId: "b", name: "party", shared: true });
+    expect(save.status).toBe(200);
+    expect(save.body.queue.ownerId).toBe(SHARED_QUEUE_OWNER);
+    expect(db.listSavedQueues(SHARED_QUEUE_OWNER, false).map((q) => q.name)).toEqual(["party"]);
+  });
+
+  it("rejects saving an empty queue", async () => {
+    const { app } = mount(true, { queue: [] });
+    const save = await request(app).post("/api/saved-queues").send({ botId: "b", name: "empty" });
+    expect(save.status).toBe(400);
+  });
+
+  it("requires botId and name", async () => {
+    const { app } = mount(true);
+    expect((await request(app).post("/api/saved-queues").send({ name: "x" })).status).toBe(400);
+    expect((await request(app).post("/api/saved-queues").send({ botId: "b" })).status).toBe(400);
+  });
+
+  it("loads a shared queue (replace by default) into the bot", async () => {
+    const { app, db, loads } = mount(true);
+    const saved = db.saveQueue(SHARED_QUEUE_OWNER, "party", [song("a"), song("b")]);
+    const load = await request(app).post(`/api/saved-queues/${saved.id}/load`).send({ botId: "b" });
+    expect(load.status).toBe(200);
+    expect(load.body).toMatchObject({ ok: true, loaded: 2, mode: "replace" });
+    expect(loads).toHaveLength(1);
+    expect(loads[0].mode).toBe("replace");
+    expect(loads[0].by).toBe("alice");
+  });
+
+  it("loads in append mode when requested", async () => {
+    const { app, db, loads } = mount(true);
+    const saved = db.saveQueue("u1", "mine", [song("a")]);
+    const load = await request(app).post(`/api/saved-queues/${saved.id}/load`).send({ botId: "b", mode: "append" });
+    expect(load.status).toBe(200);
+    expect(loads[0].mode).toBe("append");
+  });
+
+  it("404s loading another user's private queue (no existence leak)", async () => {
+    const { app, db } = mount(true);
+    db.saveQueue("someoneElse", "private", [song("z")]);
+    const other = db.listSavedQueues("someoneElse", false)[0];
+    const load = await request(app).post(`/api/saved-queues/${other.id}/load`).send({ botId: "b", mode: "replace" });
+    expect(load.status).toBe(404);
+  });
+
+  it("deletes an own queue but 404s another user's private one", async () => {
+    const { app, db } = mount(true);
+    const mine = db.saveQueue("u1", "mine", [song("a")]);
+    const theirs = db.saveQueue("someoneElse", "private", [song("z")]);
+    expect((await request(app).delete(`/api/saved-queues/${theirs.id}`)).status).toBe(404);
+    expect((await request(app).delete(`/api/saved-queues/${mine.id}`)).status).toBe(200);
+    expect(db.getSavedQueue(mine.id)).toBeNull();
+  });
+});