feat(anki): add media timing review before card creation

- Add draggable timing previews with audio playback and exact media ranges
- Support cancellation choices, including deleting existing cards

src/core/services/ipc.ts

@@ -19,6 +19,11 @@ import type {
   YoutubePickerResolveRequest,
   YoutubePickerResolveResult,
 } from '../../types';
+import type {
+  MediaTimingReviewActionResult,
+  MediaTimingReviewPreviewRequest,
+  MediaTimingReviewResolveRequest,
+} from '../../types/anki';
 import { IPC_CHANNELS, type OverlayHostedModal } from '../../shared/ipc/contracts';
 import {
   parseMpvCommand,
@@ -98,6 +103,13 @@ export interface IpcServiceDeps {
   onYoutubePickerResolve: (
     request: YoutubePickerResolveRequest,
   ) => Promise<YoutubePickerResolveResult>;
+  previewMediaTimingReview?: (
+    request: MediaTimingReviewPreviewRequest,
+  ) => Promise<MediaTimingReviewActionResult>;
+  stopMediaTimingReviewPreview?: (reviewId: string) => Promise<MediaTimingReviewActionResult>;
+  resolveMediaTimingReview?: (
+    request: MediaTimingReviewResolveRequest,
+  ) => MediaTimingReviewActionResult | Promise<MediaTimingReviewActionResult>;
   getAnkiConnectStatus: () => boolean;
   getRuntimeOptions: () => unknown;
   setRuntimeOption: (id: RuntimeOptionId, value: RuntimeOptionValue) => unknown;
@@ -221,6 +233,59 @@ function parseOverlayNotificationActionPayload(
   return { notificationId, actionId, ...(typeof noteId === 'number' ? { noteId } : {}) };
 }
 
+function parseMediaTimingReviewPreviewRequest(
+  payload: unknown,
+): MediaTimingReviewPreviewRequest | null {
+  if (!payload || typeof payload !== 'object') return null;
+  const record = payload as Record<string, unknown>;
+  if (
+    typeof record.reviewId !== 'string' ||
+    !record.reviewId ||
+    typeof record.startTime !== 'number' ||
+    !Number.isFinite(record.startTime) ||
+    typeof record.endTime !== 'number' ||
+    !Number.isFinite(record.endTime)
+  ) {
+    return null;
+  }
+  return {
+    reviewId: record.reviewId,
+    startTime: record.startTime,
+    endTime: record.endTime,
+  };
+}
+
+function parseMediaTimingReviewResolveRequest(
+  payload: unknown,
+): MediaTimingReviewResolveRequest | null {
+  if (!payload || typeof payload !== 'object') return null;
+  const record = payload as Record<string, unknown>;
+  if (typeof record.reviewId !== 'string' || !record.reviewId) return null;
+  const decision = record.decision;
+  if (!decision || typeof decision !== 'object') return null;
+  const decisionRecord = decision as Record<string, unknown>;
+  if (decisionRecord.action === 'use-original' || decisionRecord.action === 'discard') {
+    return { reviewId: record.reviewId, decision: { action: decisionRecord.action } };
+  }
+  if (
+    decisionRecord.action === 'confirm' &&
+    typeof decisionRecord.startTime === 'number' &&
+    Number.isFinite(decisionRecord.startTime) &&
+    typeof decisionRecord.endTime === 'number' &&
+    Number.isFinite(decisionRecord.endTime)
+  ) {
+    return {
+      reviewId: record.reviewId,
+      decision: {
+        action: 'confirm',
+        startTime: decisionRecord.startTime,
+        endTime: decisionRecord.endTime,
+      },
+    };
+  }
+  return null;
+}
+
 export interface IpcDepsRuntimeOptions {
   getMainWindow: () => WindowLike | null;
   getVisibleOverlayVisibility: () => boolean;
@@ -277,6 +342,9 @@ export interface IpcDepsRuntimeOptions {
   onYoutubePickerResolve: (
     request: YoutubePickerResolveRequest,
   ) => Promise<YoutubePickerResolveResult>;
+  previewMediaTimingReview?: IpcServiceDeps['previewMediaTimingReview'];
+  stopMediaTimingReviewPreview?: IpcServiceDeps['stopMediaTimingReviewPreview'];
+  resolveMediaTimingReview?: IpcServiceDeps['resolveMediaTimingReview'];
   getAnkiConnectStatus: () => boolean;
   getRuntimeOptions: () => unknown;
   setRuntimeOption: (id: RuntimeOptionId, value: RuntimeOptionValue) => unknown;
@@ -370,6 +438,9 @@ export function createIpcDepsRuntime(options: IpcDepsRuntimeOptions): IpcService
       options.activatePlaybackWindowForOverlayInteraction ?? (() => false),
     runSubsyncManual: options.runSubsyncManual,
     onYoutubePickerResolve: options.onYoutubePickerResolve,
+    previewMediaTimingReview: options.previewMediaTimingReview,
+    stopMediaTimingReviewPreview: options.stopMediaTimingReviewPreview,
+    resolveMediaTimingReview: options.resolveMediaTimingReview,
     getAnkiConnectStatus: options.getAnkiConnectStatus,
     getRuntimeOptions: options.getRuntimeOptions,
     setRuntimeOption: options.setRuntimeOption,
@@ -491,6 +562,36 @@ export function registerIpcHandlers(deps: IpcServiceDeps, ipc: IpcMainRegistrar
     },
   );
 
+  ipc.handle(
+    IPC_CHANNELS.request.mediaTimingReviewPreview,
+    async (_event: unknown, payload: unknown) => {
+      const request = parseMediaTimingReviewPreviewRequest(payload);
+      if (!request || !deps.previewMediaTimingReview) {
+        return { ok: false, message: 'Timing preview is unavailable.' };
+      }
+      return await deps.previewMediaTimingReview(request);
+    },
+  );
+  ipc.handle(
+    IPC_CHANNELS.request.mediaTimingReviewStopPreview,
+    async (_event: unknown, reviewId: unknown) => {
+      if (typeof reviewId !== 'string' || !reviewId || !deps.stopMediaTimingReviewPreview) {
+        return { ok: false, message: 'Timing preview is unavailable.' };
+      }
+      return await deps.stopMediaTimingReviewPreview(reviewId);
+    },
+  );
+  ipc.handle(
+    IPC_CHANNELS.request.mediaTimingReviewResolve,
+    async (_event: unknown, payload: unknown) => {
+      const request = parseMediaTimingReviewResolveRequest(payload);
+      if (!request || !deps.resolveMediaTimingReview) {
+        return { ok: false, message: 'Timing review is unavailable.' };
+      }
+      return await deps.resolveMediaTimingReview(request);
+    },
+  );
+
   ipc.on(IPC_CHANNELS.command.openYomitanSettings, () => {
     deps.openYomitanSettings();
   });

src/core/services/media-timing-preview.test.ts

@@ -0,0 +1,144 @@
+import assert from 'node:assert/strict';
+import { EventEmitter } from 'node:events';
+import net from 'node:net';
+import { describe, test } from 'node:test';
+import { buildMediaTimingPreviewArgs, MediaTimingPreviewSession } from './media-timing-preview';
+
+describe('buildMediaTimingPreviewArgs', () => {
+  test('creates a hidden audio-only reusable mpv session', () => {
+    const args = buildMediaTimingPreviewArgs('/tmp/review.sock', {
+      mediaPath: '/video/show.mkv',
+      audioTrackId: 3,
+      volume: 55,
+    });
+
+    assert.ok(args.includes('--no-video'));
+    assert.ok(args.includes('--force-window=no'));
+    assert.ok(args.includes('--idle=yes'));
+    assert.ok(args.includes('--pause=yes'));
+    assert.ok(args.includes('--input-ipc-server=/tmp/review.sock'));
+    assert.ok(args.includes('--aid=3'));
+    assert.ok(args.includes('--volume=55'));
+    assert.equal(args.at(-2), '--');
+    assert.equal(args.at(-1), '/video/show.mkv');
+  });
+});
+
+test('preview session handles socket errors after connecting', async () => {
+  const socket = new net.Socket();
+  const child = new EventEmitter() as EventEmitter & { kill: () => boolean };
+  child.kill = () => true;
+  const session = new MediaTimingPreviewSession({
+    platform: 'linux',
+    spawnProcess: () => child as never,
+    connectSocket: () => {
+      queueMicrotask(() => socket.emit('connect'));
+      return socket;
+    },
+    removeSocketFile: () => undefined,
+    createSocketPath: () => '/tmp/review.sock',
+  });
+
+  await session.start({ mediaPath: '/video/show.mkv' });
+  assert.doesNotThrow(() => socket.emit('error', new Error('pipe closed')));
+  await assert.rejects(session.play(1, 2), /not ready/);
+  session.dispose();
+});
+
+test('preview session rejects a connection that finishes after disposal', async () => {
+  const socket = new net.Socket();
+  const child = new EventEmitter() as EventEmitter & { kill: () => boolean };
+  child.kill = () => true;
+  const session = new MediaTimingPreviewSession({
+    platform: 'linux',
+    spawnProcess: () => child as never,
+    connectSocket: () => socket,
+    removeSocketFile: () => undefined,
+    createSocketPath: () => '/tmp/review.sock',
+  });
+
+  const pendingStart = session.start({ mediaPath: '-playlist' });
+  session.dispose();
+  socket.emit('connect');
+
+  await assert.rejects(pendingStart, /closed/);
+  assert.equal(socket.destroyed, true);
+});
+
+test('preview session shares one startup across concurrent start calls', async () => {
+  const socket = new net.Socket();
+  const child = new EventEmitter() as EventEmitter & { kill: () => boolean };
+  child.kill = () => true;
+  let spawnCount = 0;
+  const session = new MediaTimingPreviewSession({
+    platform: 'linux',
+    spawnProcess: () => {
+      spawnCount += 1;
+      return child as never;
+    },
+    connectSocket: () => socket,
+    removeSocketFile: () => undefined,
+    createSocketPath: () => '/tmp/review.sock',
+  });
+
+  const firstStart = session.start({ mediaPath: '/video/show.mkv' });
+  const secondStart = session.start({ mediaPath: '/video/show.mkv' });
+  socket.emit('connect');
+
+  await Promise.all([firstStart, secondStart]);
+  assert.equal(spawnCount, 1);
+  session.dispose();
+});
+
+test('preview session can start again after a startup failure', async () => {
+  const socket = new net.Socket();
+  const child = new EventEmitter() as EventEmitter & { kill: () => boolean };
+  child.kill = () => true;
+  let spawnCount = 0;
+  const session = new MediaTimingPreviewSession({
+    platform: 'linux',
+    spawnProcess: () => {
+      spawnCount += 1;
+      if (spawnCount === 1) throw new Error('spawn failed');
+      return child as never;
+    },
+    connectSocket: () => {
+      queueMicrotask(() => socket.emit('connect'));
+      return socket;
+    },
+    removeSocketFile: () => undefined,
+    createSocketPath: () => '/tmp/review.sock',
+  });
+
+  await assert.rejects(session.start({ mediaPath: '/video/show.mkv' }), /spawn failed/);
+  await session.start({ mediaPath: '/video/show.mkv' });
+  assert.equal(spawnCount, 2);
+  session.dispose();
+});
+
+test('preview session bounds a connection attempt that never settles', async () => {
+  const child = new EventEmitter() as EventEmitter & { kill: () => boolean };
+  child.kill = () => true;
+  let nowMs = 0;
+  let connectAttempts = 0;
+  const session = new MediaTimingPreviewSession({
+    platform: 'linux',
+    spawnProcess: () => child as never,
+    connectSocket: () => {
+      connectAttempts += 1;
+      return new net.Socket();
+    },
+    now: () => {
+      const current = nowMs;
+      nowMs += 1_000;
+      return current;
+    },
+    schedule: (callback) => setTimeout(callback, 0),
+    cancelSchedule: (timeout) => clearTimeout(timeout),
+    removeSocketFile: () => undefined,
+    createSocketPath: () => '/tmp/review.sock',
+  });
+
+  await assert.rejects(session.start({ mediaPath: '/video/show.mkv' }), /Timed out starting/);
+  assert.equal(connectAttempts, 1);
+});

src/core/services/media-timing-preview.ts

@@ -0,0 +1,309 @@
+import { spawn, type ChildProcess } from 'child_process';
+import fs from 'fs';
+import net, { type Socket } from 'net';
+import os from 'os';
+import path from 'path';
+import { randomUUID } from 'crypto';
+
+const CONNECT_TIMEOUT_MS = 5_000;
+const CONNECT_ATTEMPT_TIMEOUT_MS = 500;
+const CONNECT_RETRY_MS = 40;
+
+export interface MediaTimingPreviewStartOptions {
+  mediaPath: string;
+  executablePath?: string;
+  audioTrackId?: number;
+  volume?: number;
+}
+
+type PreviewProcess = Pick<ChildProcess, 'kill' | 'once'>;
+
+interface MediaTimingPreviewDeps {
+  platform: NodeJS.Platform;
+  spawnProcess: (command: string, args: string[]) => PreviewProcess;
+  connectSocket: (socketPath: string) => Socket;
+  now: () => number;
+  schedule: (callback: () => void, delayMs: number) => ReturnType<typeof setTimeout>;
+  cancelSchedule: (timeout: ReturnType<typeof setTimeout>) => void;
+  removeSocketFile: (socketPath: string) => void;
+  createSocketPath: () => string;
+}
+
+export function buildMediaTimingPreviewArgs(
+  socketPath: string,
+  options: MediaTimingPreviewStartOptions,
+): string[] {
+  const args = [
+    '--no-config',
+    '--no-video',
+    '--audio-display=no',
+    '--force-window=no',
+    '--idle=yes',
+    '--keep-open=yes',
+    '--pause=yes',
+    '--terminal=no',
+    '--msg-level=all=warn',
+    `--input-ipc-server=${socketPath}`,
+  ];
+  if (typeof options.audioTrackId === 'number' && Number.isInteger(options.audioTrackId)) {
+    args.push(`--aid=${options.audioTrackId}`);
+  }
+  if (typeof options.volume === 'number' && Number.isFinite(options.volume)) {
+    args.push(`--volume=${Math.max(0, options.volume)}`);
+  }
+  args.push('--', options.mediaPath);
+  return args;
+}
+
+function createDefaultSocketPath(): string {
+  const suffix = `${process.pid}-${randomUUID()}`;
+  return process.platform === 'win32'
+    ? `\\\\.\\pipe\\subminer-timing-preview-${suffix}`
+    : path.join(os.tmpdir(), `subminer-timing-preview-${suffix}.sock`);
+}
+
+function removePosixSocketFile(socketPath: string): void {
+  if (process.platform === 'win32') return;
+  try {
+    fs.unlinkSync(socketPath);
+  } catch (error) {
+    if ((error as NodeJS.ErrnoException).code !== 'ENOENT') {
+      throw error;
+    }
+  }
+}
+
+export class MediaTimingPreviewSession {
+  private readonly deps: MediaTimingPreviewDeps;
+  private socketPath: string | null = null;
+  private socket: Socket | null = null;
+  private process: PreviewProcess | null = null;
+  private startupError: Error | null = null;
+  private startPromise: Promise<void> | null = null;
+  private retryWait: {
+    timeout: ReturnType<typeof setTimeout>;
+    resolve: () => void;
+  } | null = null;
+  private disposed = false;
+
+  constructor(deps: Partial<MediaTimingPreviewDeps> = {}) {
+    this.deps = {
+      platform: process.platform,
+      spawnProcess: (command, args) => spawn(command, args, { stdio: 'ignore' }),
+      connectSocket: (socketPath) => net.createConnection(socketPath),
+      now: Date.now,
+      schedule: (callback, delayMs) => setTimeout(callback, delayMs),
+      cancelSchedule: (timeout) => clearTimeout(timeout),
+      removeSocketFile: removePosixSocketFile,
+      createSocketPath: createDefaultSocketPath,
+      ...deps,
+    };
+  }
+
+  async start(options: MediaTimingPreviewStartOptions): Promise<void> {
+    if (this.disposed) throw new Error('Preview session is closed');
+    if (this.socket) return;
+    if (this.startPromise) return await this.startPromise;
+
+    const startPromise = this.startOnce(options);
+    this.startPromise = startPromise;
+    try {
+      await startPromise;
+    } catch (error) {
+      this.releaseResources();
+      throw error;
+    } finally {
+      if (this.startPromise === startPromise) this.startPromise = null;
+    }
+  }
+
+  private async startOnce(options: MediaTimingPreviewStartOptions): Promise<void> {
+    const mediaPath = options.mediaPath.trim();
+    if (!mediaPath) throw new Error('No media source is available for preview');
+
+    const socketPath = this.deps.createSocketPath();
+    this.socketPath = socketPath;
+    if (this.deps.platform !== 'win32') {
+      this.deps.removeSocketFile(socketPath);
+    }
+
+    const command = options.executablePath?.trim() || 'mpv';
+    this.startupError = null;
+    const child = this.deps.spawnProcess(
+      command,
+      buildMediaTimingPreviewArgs(socketPath, { ...options, mediaPath }),
+    );
+    this.process = child;
+    child.once('error', (error) => {
+      if (this.process !== child) return;
+      this.startupError = error;
+    });
+    child.once('exit', () => {
+      if (this.process !== child) return;
+      if (!this.socket && !this.disposed && !this.startupError) {
+        this.startupError = new Error('The hidden mpv preview player exited during startup');
+      }
+      this.socket?.destroy();
+      this.socket = null;
+      this.process = null;
+    });
+
+    await this.connectWithRetry(socketPath);
+  }
+
+  async play(startTime: number, endTime: number): Promise<void> {
+    if (!this.socket || this.socket.destroyed) {
+      throw new Error('Preview player is not ready');
+    }
+    if (!Number.isFinite(startTime) || !Number.isFinite(endTime) || endTime <= startTime) {
+      throw new Error('Preview timing is invalid');
+    }
+
+    this.send(['set_property', 'pause', true]);
+    this.send(['set_property', 'ab-loop-a', startTime]);
+    this.send(['set_property', 'ab-loop-b', endTime]);
+    this.send(['seek', startTime, 'absolute+exact']);
+    this.send(['set_property', 'pause', false]);
+  }
+
+  async stop(): Promise<void> {
+    if (!this.socket || this.socket.destroyed) return;
+    this.send(['set_property', 'pause', true]);
+  }
+
+  dispose(): void {
+    if (this.disposed) return;
+    this.disposed = true;
+    this.releaseResources();
+  }
+
+  private releaseResources(): void {
+    this.cancelRetryWait();
+    try {
+      this.send(['quit']);
+    } catch {
+      // The process may already have exited.
+    }
+    this.socket?.end();
+    this.socket?.destroy();
+    this.socket = null;
+    const child = this.process;
+    this.process = null;
+    child?.kill();
+    if (this.socketPath && this.deps.platform !== 'win32') {
+      try {
+        this.deps.removeSocketFile(this.socketPath);
+      } catch {
+        // mpv may still be releasing the socket. The OS temp directory owns cleanup.
+      }
+    }
+    this.socketPath = null;
+  }
+
+  private send(command: Array<string | number | boolean>): void {
+    if (!this.socket || this.socket.destroyed) {
+      throw new Error('Preview player is not connected');
+    }
+    this.socket.write(`${JSON.stringify({ command })}\n`);
+  }
+
+  private async connectWithRetry(socketPath: string): Promise<void> {
+    const deadline = this.deps.now() + CONNECT_TIMEOUT_MS;
+    while (!this.disposed && this.deps.now() < deadline) {
+      if (this.startupError) {
+        throw this.startupError;
+      }
+      try {
+        const remainingMs = deadline - this.deps.now();
+        if (remainingMs <= 0) break;
+        const socket = await this.connectOnce(
+          socketPath,
+          Math.min(CONNECT_ATTEMPT_TIMEOUT_MS, remainingMs),
+        );
+        if (this.disposed) {
+          socket.destroy();
+          throw new Error('Preview session is closed');
+        }
+        this.socket = socket;
+        return;
+      } catch {
+        if (this.disposed) {
+          throw new Error('Preview session is closed');
+        }
+        const remainingMs = deadline - this.deps.now();
+        if (remainingMs <= 0) break;
+        await this.waitForRetry(Math.min(CONNECT_RETRY_MS, remainingMs));
+      }
+    }
+    if (this.startupError) {
+      throw this.startupError;
+    }
+    if (this.disposed) {
+      throw new Error('Preview session is closed');
+    }
+    throw new Error('Timed out starting the hidden mpv preview player');
+  }
+
+  private waitForRetry(delayMs: number): Promise<void> {
+    return new Promise<void>((resolve) => {
+      const timeout = this.deps.schedule(() => {
+        if (this.retryWait?.timeout === timeout) this.retryWait = null;
+        resolve();
+      }, delayMs);
+      this.retryWait = { timeout, resolve };
+    });
+  }
+
+  private cancelRetryWait(): void {
+    const pending = this.retryWait;
+    this.retryWait = null;
+    if (!pending) return;
+    this.deps.cancelSchedule(pending.timeout);
+    pending.resolve();
+  }
+
+  private connectOnce(socketPath: string, timeoutMs: number): Promise<Socket> {
+    return new Promise<Socket>((resolve, reject) => {
+      let timeout: ReturnType<typeof setTimeout> | null = null;
+      let settled = false;
+      const clearAttemptTimeout = (): void => {
+        if (timeout !== null) this.deps.cancelSchedule(timeout);
+        timeout = null;
+      };
+      const socket = this.deps.connectSocket(socketPath);
+      const onConnect = (): void => {
+        if (settled) return;
+        settled = true;
+        clearAttemptTimeout();
+        socket.off('error', onError);
+        socket.on('error', () => {
+          socket.destroy();
+          if (this.socket === socket) this.socket = null;
+        });
+        socket.once('close', () => {
+          if (this.socket === socket) this.socket = null;
+        });
+        resolve(socket);
+      };
+      const onError = (error: Error): void => {
+        if (settled) return;
+        settled = true;
+        clearAttemptTimeout();
+        socket.off('connect', onConnect);
+        socket.destroy();
+        reject(error);
+      };
+      socket.once('connect', onConnect);
+      socket.once('error', onError);
+      timeout = this.deps.schedule(() => {
+        if (settled) return;
+        settled = true;
+        timeout = null;
+        socket.off('connect', onConnect);
+        socket.off('error', onError);
+        socket.destroy();
+        reject(new Error('Timed out connecting to the hidden mpv preview player'));
+      }, timeoutMs);
+    });
+  }
+}