Method execute

src/tools/media/ffmpeg-tools.ts:79–146

(a: z.infer<typeof TransformArgs>)

  isReadOnly = false; isDestructive = true; argsSchema = TransformArgs;

  async execute(a: z.infer<typeof TransformArgs>): Promise<ToolResult> {
    // ---- concat: join an ordered list of clips into one final video ----
    // Uses the concat demuxer. Default -c copy is lossless + fast and works when
    // all clips share codec/resolution (the typical same-preset AI-generated case);
    // reencode:true normalizes mismatched sources.
    if (a.operation === 'concat') {
      const inputs = a.inputs ?? [];
      if (inputs.length < 2) {
        return { content: 'concat requires "inputs" with at least 2 clip paths, in play order.', isError: true };
      }
      const listLines = inputs.map(f => `file '${path.resolve(f).replace(/'/g, "'\\''")}'`);
      const listPath = path.join(os.tmpdir(), `qodex-concat-${Date.now()}-${Math.random().toString(36).slice(2)}.txt`);
      try {
        await fs.writeFile(listPath, listLines.join('\n') + '\n', 'utf8');
        const cargs: string[] = [];
        if (a.overwrite) cargs.push('-y');
        cargs.push('-f', 'concat', '-safe', '0', '-i', listPath);
        if (a.reencode) cargs.push('-c:v', 'libx264', '-crf', '18', '-preset', 'veryfast', '-pix_fmt', 'yuv420p');
        else cargs.push('-c', 'copy');
        cargs.push(a.output);
        const r = await runProcess('ffmpeg', cargs, { timeoutMs: (a.timeout_seconds ?? 600) * 1000 });
        if (r.notFound) return { content: notInstalledMessage('ffmpeg', FFMPEG_HINT), isError: true };
        if (r.timedOut) return { content: 'ffmpeg concat timed out. For many/long clips use background_job_start.', isError: true };
        if (!r.ok) {
          const hint = a.reencode ? '' : '\nIf clips differ in codec/resolution, retry with reencode:true (or normalize them first with resize/convert).';
          return { content: `ffmpeg concat failed:\n${r.stderr.trim().slice(-1500)}${hint}`, isError: true };
        }
        return { content: `✓ concat ${inputs.length} clips → ${a.output}` };
      } finally {
        try { await fs.unlink(listPath); } catch { /* ignore temp cleanup */ }
      }
    }

    if (!a.input) return { content: `Operation "${a.operation}" requires "input".`, isError: true };
    const input: string = a.input;
    const args: string[] = [];
    if (a.overwrite) args.push('-y');

    switch (a.operation) {
      case 'convert':
        args.push('-i', input, a.output);
        break;
      case 'trim':
        if (!a.start) return { content: 'trim requires "start".', isError: true };
        args.push('-i', input, '-ss', a.start);
        if (a.end) args.push('-to', a.end);
        args.push('-c', 'copy', a.output);
        break;
      case 'extract_frame':
        args.push('-ss', a.start ?? '0', '-i', input, '-frames:v', '1', a.output);
        break;
      case 'resize': {
        if (!a.width && !a.height) return { content: 'resize requires width and/or height.', isError: true };
        const w = a.width ?? -1, h = a.height ?? -1;
        args.push('-i', input, '-vf', `scale=${w}:${h}`, a.output);
        break;
      }
      case 'extract_audio':