feat: persist volume, play mode and audio quality across restarts

Runtime playback settings were kept only in memory (AudioPlayer.volume,
PlayQueue.mode, each provider's quality field), so restarting the bot reset
them to defaults and users had to re-tune volume and quality every time (#125).

Persist and restore them via the repo's existing storage:
- Volume and play mode are per-bot, stored on new bot_instances columns
  (volume, play_mode) with a schema migration; restored when the instance is
  (re)built, written by cmdVol / cmdMode which every entry point (chat command,
  WebUI, REST) funnels through. Volume and mode are written independently so a
  transient !fm/!artist mode switch never overwrites the user's saved !mode.
- Per-provider audio quality is global (shared providers), stored in a new
  config.json `audioQuality` block; applied to the providers at startup and
  re-snapshotted on POST /api/music/quality.

Queue, current song, progress and FM/artist sessions stay ephemeral.

Adds tests for config sanitize/round-trip, DB player-settings + migration,
cmdVol/cmdMode persistence + construction-time restore, and quality persistence
through the REST endpoint. Documents the behavior in the README.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

README.md

@@ -414,6 +414,20 @@ sudo systemctl start tsmusicbot
 
 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
 
 ```

src/bot/instance.test.ts

@@ -6,6 +6,7 @@ import type { SpotifyController } from "../music/spotify/controller.js";
 import type { SpotifyOAuth } from "../music/spotify/spotify-oauth.js";
 import type { MusicProvider } from "../music/provider.js";
 import type { BotDatabase } from "../data/database.js";
+import { createDatabase } from "../data/database.js";
 import type { AvatarStore } from "../data/avatars.js";
 import type { BotConfig } from "../data/config.js";
 
@@ -832,6 +833,9 @@ describe("BotInstance — spotifyOAuth threading to the controller factory (C3.1
     const database = {
       getProfileConfig: () => ({}),
       getCustomAvatarPath: () => null,
+      getPlayerSettings: () => ({ volume: 75, playMode: "seq" }),
+      saveVolume: () => {},
+      savePlayMode: () => {},
     } as unknown as BotDatabase;
     const options: BotInstanceOptions = {
       id: "bot-oauth-test",
@@ -912,6 +916,136 @@ describe("spotifyPortsForBotId — per-bot go-librespot ports (Fix 3)", () => {
   });
 });
 
+// --- Persisting volume + play mode across restarts (#125) ------------------
+const cmdVol = (BotInstance.prototype as any).cmdVol as (this: unknown, cmd: any) => string;
+const cmdMode = (BotInstance.prototype as any).cmdMode as (this: unknown, cmd: any) => string;
+
+describe("BotInstance.cmdVol — persistence (#125)", () => {
+  function makeVolCtx() {
+    let stored = 75;
+    return {
+      id: "bot1",
+      player: {
+        setVolume: vi.fn((v: number) => { stored = v; }),
+        getVolume: vi.fn(() => stored),
+      },
+      database: { saveVolume: vi.fn() },
+      logger: { warn: vi.fn() },
+      emit: vi.fn(),
+      // The real private persist helper lives on the prototype; wire it so the
+      // test exercises the shipped persistence path end-to-end.
+      persistVolume: (BotInstance.prototype as any).persistVolume,
+    } as any;
+  }
+
+  it("saves the new volume via database.saveVolume (covers chat !vol AND the REST endpoint)", () => {
+    const ctx = makeVolCtx();
+    const res = cmdVol.call(ctx, { args: "40" });
+    expect(res).toBe("Volume set to 40%");
+    expect(ctx.player.setVolume).toHaveBeenCalledWith(40);
+    expect(ctx.database.saveVolume).toHaveBeenCalledWith("bot1", 40);
+    expect(ctx.emit).toHaveBeenCalledWith("stateChange");
+  });
+
+  it("does not persist an out-of-range volume", () => {
+    const ctx = makeVolCtx();
+    const res = cmdVol.call(ctx, { args: "999" });
+    expect(res).toBe("Usage: !vol <0-100>");
+    expect(ctx.player.setVolume).not.toHaveBeenCalled();
+    expect(ctx.database.saveVolume).not.toHaveBeenCalled();
+  });
+
+  it("swallows a database error so the volume change still succeeds", () => {
+    const ctx = makeVolCtx();
+    ctx.database.saveVolume = vi.fn(() => { throw new Error("disk full"); });
+    const res = cmdVol.call(ctx, { args: "50" });
+    expect(res).toBe("Volume set to 50%");
+    expect(ctx.player.setVolume).toHaveBeenCalledWith(50);
+    expect(ctx.logger.warn).toHaveBeenCalled();
+  });
+});
+
+describe("BotInstance.cmdMode — persistence (#125)", () => {
+  function makeModeCtx() {
+    let mode = "seq";
+    return {
+      id: "bot1",
+      queue: {
+        setMode: vi.fn((m: string) => { mode = m; }),
+        getMode: vi.fn(() => mode),
+      },
+      database: { savePlayMode: vi.fn() },
+      logger: { warn: vi.fn() },
+      emit: vi.fn(),
+      persistPlayMode: (BotInstance.prototype as any).persistPlayMode,
+    } as any;
+  }
+
+  it("saves the new play mode via database.savePlayMode", () => {
+    const ctx = makeModeCtx();
+    const res = cmdMode.call(ctx, { args: "rloop" });
+    expect(res).toBe("Play mode set to: rloop");
+    expect(ctx.queue.setMode).toHaveBeenCalledWith("rloop");
+    expect(ctx.database.savePlayMode).toHaveBeenCalledWith("bot1", "rloop");
+    expect(ctx.emit).toHaveBeenCalledWith("stateChange");
+  });
+
+  it("does not persist an unknown mode", () => {
+    const ctx = makeModeCtx();
+    const res = cmdMode.call(ctx, { args: "bogus" });
+    expect(res).toBe("Usage: !mode <seq|loop|random|rloop>");
+    expect(ctx.queue.setMode).not.toHaveBeenCalled();
+    expect(ctx.database.savePlayMode).not.toHaveBeenCalled();
+  });
+});
+
+describe("BotInstance — restores persisted player settings on construction (#125)", () => {
+  const provider = { platform: "netease" } as unknown as MusicProvider;
+  function makeOptions(id: string, database: BotDatabase): BotInstanceOptions {
+    const logger: any = { info() {}, warn() {}, error() {}, debug() {}, child() { return logger; } };
+    return {
+      id,
+      name: "RestoreBot",
+      tsOptions: { host: "localhost", port: 9987, queryPort: 10011, nickname: "RestoreBot" } as any,
+      neteaseProvider: provider,
+      qqProvider: provider,
+      bilibiliProvider: provider,
+      youtubeProvider: provider,
+      database,
+      config: { spotify: {} } as unknown as BotConfig,
+      logger,
+      avatarStore: { read: () => null } as unknown as AvatarStore,
+      spotifyControllerFactory: () => ({ on: () => {} } as unknown as SpotifyController),
+    };
+  }
+
+  it("applies the saved volume + play mode from the database", () => {
+    const db = createDatabase(":memory:");
+    db.saveBotInstance({
+      id: "bot-restore", name: "B", serverAddress: "x", serverPort: 9987, nickname: "n",
+      defaultChannel: "", channelId: "", channelPassword: "", autoStart: false,
+      serverProtocol: "", ts6ApiKey: "", serverPassword: "",
+    });
+    db.saveVolume("bot-restore", 33);
+    db.savePlayMode("bot-restore", "loop");
+
+    const bot = new BotInstance(makeOptions("bot-restore", db));
+    const status = bot.getStatus();
+    expect(status.volume).toBe(33);
+    expect(status.playMode).toBe("loop");
+    db.close();
+  });
+
+  it("falls back to defaults for a bot with no saved settings", () => {
+    const db = createDatabase(":memory:");
+    const bot = new BotInstance(makeOptions("brand-new", db));
+    const status = bot.getStatus();
+    expect(status.volume).toBe(75);
+    expect(status.playMode).toBe("seq");
+    db.close();
+  });
+});
+
 describe("BotInstance.handleTextMessage — response chunking (#116)", () => {
   it("splits a long command response into multiple sends, each under the byte cap", async () => {
     const ctx = makeGateCtx({ adminGroups: [] });

src/bot/instance.ts

@@ -39,6 +39,15 @@ import type { SpotifyOAuth } from "../music/spotify/spotify-oauth.js";
 /** Reply sent when a non-admin invokes an admin-only chat command. */
 export const COMMAND_DENIED_MESSAGE = "⛔ 需要管理员权限（该命令仅限管理员服务器组）";
 
+/** Maps the persisted / command-line play-mode string to the PlayMode enum.
+ *  Shared by the !mode command and the restart-restore path (#125). */
+const PLAY_MODE_BY_VALUE: Record<string, PlayMode> = {
+  seq: PlayMode.Sequential,
+  loop: PlayMode.Loop,
+  random: PlayMode.Random,
+  rloop: PlayMode.RandomLoop,
+};
+
 /** Fallback message when Spotify audio can't be served (backend unavailable
  *  OR a per-track playTrack failure against a dead/failed sidecar). */
 const SPOTIFY_UNAVAILABLE_MESSAGE =
@@ -188,6 +197,19 @@ export class BotInstance extends EventEmitter {
     this.player = new AudioPlayer(this.logger);
     this.queue = new PlayQueue();
 
+    // Restore persisted per-bot player settings (#125): volume + play mode
+    // survive restarts. getPlayerSettings returns validated values (the in-memory
+    // defaults when the row/column is absent), so this is a harmless no-op for a
+    // brand-new bot and reproduces the saved state for an existing one.
+    try {
+      const settings = this.database.getPlayerSettings(this.id);
+      this.player.setVolume(settings.volume);
+      const restoredMode = PLAY_MODE_BY_VALUE[settings.playMode];
+      if (restoredMode) this.queue.setMode(restoredMode);
+    } catch (err) {
+      this.logger.warn({ err }, "Failed to restore player settings — using defaults");
+    }
+
     // Structural typing (like localProvider.sweepUnreferenced): only the real
     // JellyfinProvider exposes createPlaybackReporter, so the netease fallback
     // provider simply leaves reporting off.
@@ -1136,10 +1158,36 @@ export class BotInstance extends EventEmitter {
     const vol = parseInt(cmd.args, 10);
     if (isNaN(vol) || vol < 0 || vol > 100) return "Usage: !vol <0-100>";
     this.player.setVolume(vol);
+    // Persist so the volume survives a restart (#125). Both the chat !vol command
+    // and the WebUI/REST volume endpoint funnel through here, so one write covers
+    // every entry point. Only volume is written — play mode is saved independently.
+    this.persistVolume();
     this.emit("stateChange");
     return `Volume set to ${vol}%`;
   }
 
+  /** Persist the current volume (#125). Best-effort: a DB error must never break
+   *  the volume change itself. */
+  private persistVolume(): void {
+    try {
+      this.database.saveVolume(this.id, this.player.getVolume());
+    } catch (err) {
+      this.logger.warn({ err }, "Failed to persist volume");
+    }
+  }
+
+  /** Persist the current play mode (#125). Best-effort, mirrors persistVolume.
+   *  Called ONLY from the explicit !mode command — NOT from FM/artist mode, whose
+   *  Random/Loop switch is a transient side effect that must not overwrite the
+   *  user's saved preference. */
+  private persistPlayMode(): void {
+    try {
+      this.database.savePlayMode(this.id, this.queue.getMode());
+    } catch (err) {
+      this.logger.warn({ err }, "Failed to persist play mode");
+    }
+  }
+
   private cmdNow(): string {
     const song = this.queue.current();
     if (!song) return "Nothing is playing";
@@ -1205,15 +1253,12 @@ export class BotInstance extends EventEmitter {
   }
 
   private cmdMode(cmd: ParsedCommand): string {
-    const modeMap: Record<string, PlayMode> = {
+    const mode = PLAY_MODE_BY_VALUE[cmd.args];
-      seq: PlayMode.Sequential,
-      loop: PlayMode.Loop,
-      random: PlayMode.Random,
-      rloop: PlayMode.RandomLoop,
-    };
-    const mode = modeMap[cmd.args];
     if (mode === undefined) return "Usage: !mode <seq|loop|random|rloop>";
     this.queue.setMode(mode);
+    // Persist so the play mode survives a restart (#125). The chat !mode command
+    // and the WebUI/REST mode endpoint both funnel through here.
+    this.persistPlayMode();
     this.emit("stateChange");
     return `Play mode set to: ${cmd.args}`;
   }

src/data/config.test.ts

@@ -92,6 +92,60 @@ describe("config", () => {
     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");

src/data/config.ts

@@ -38,6 +38,22 @@ export interface JellyfinConfig {
   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;
+}
+
 /**
  * Providers gated by `enabledProviders`. Not listed here:
  *  - "local"   → governed by the existing `localAudioEnabled` flag
@@ -102,6 +118,8 @@ export interface BotConfig {
   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
@@ -162,6 +180,15 @@ export function getDefaultConfig(): BotConfig {
       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"],
   };
 }
@@ -317,6 +344,20 @@ export function loadConfig(path: string): BotConfig {
         )
       : defaults.enabledProviders;
 
+    // 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,
@@ -324,6 +365,7 @@ export function loadConfig(path: string): BotConfig {
       guestMode: gm,
       spotify,
       jellyfin,
+      audioQuality,
       enabledProviders,
     };
   }

src/data/database.test.ts

@@ -131,6 +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",

src/data/database.ts

@@ -55,6 +55,26 @@ 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;
@@ -75,6 +95,9 @@ 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;
@@ -119,6 +142,15 @@ 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);
@@ -161,6 +193,8 @@ 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
     );
 
@@ -321,6 +355,12 @@ 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 = ?`);
 
@@ -406,6 +446,36 @@ 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;

src/index.ts

@@ -100,6 +100,15 @@ async function main() {
   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).

src/web/api/music.test.ts

@@ -1,9 +1,19 @@
-import { describe, it, expect, vi, beforeEach } from "vitest";
+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, type BotConfig } from "../../data/config.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 } from "./music.js";
 
 const empty: SearchResult = { songs: [], albums: [], playlists: [] };
@@ -147,3 +157,122 @@ describe("music router provider gating (enabledProviders) + jellyfin endpoints",
     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");
+  });
+});

src/web/api/music.ts

@@ -2,7 +2,7 @@ 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 { isProviderEnabled, defaultPlatform, 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";
@@ -16,7 +16,10 @@ export function createMusicRouter(
   config?: BotConfig,
   kugouProvider?: MusicProvider,
   spotifyProvider?: MusicProvider,
-  jellyfinProvider?: 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();
@@ -480,6 +483,26 @@ export function createMusicRouter(
     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/server.ts

@@ -151,7 +151,7 @@ export function createWebServer(options: WebServerOptions): WebServer {
   );
   app.use(
     "/api/music",
-    createMusicRouter(options.neteaseProvider, options.qqProvider, options.bilibiliProvider, logger, options.localProvider, options.config, options.kugouProvider, options.spotifyProvider, options.jellyfinProvider)
+    createMusicRouter(options.neteaseProvider, options.qqProvider, options.bilibiliProvider, logger, options.localProvider, options.config, options.kugouProvider, options.spotifyProvider, options.jellyfinProvider, options.configPath)
   );
   app.use("/api/player", createPlayerRouter(
     options.botManager, logger, options.database,