feat: Add YouTube subtitle generation script

youtube_to_srt.py

@@ -0,0 +1,86 @@
+#!/usr/bin/env -S uv run --script
+# /// script
+# dependencies = ["yt-dlp"]
+# ///
+import argparse
+import logging
+import re
+import subprocess
+import tempfile
+from pathlib import Path
+
+import yt_dlp
+
+VIDEO_TO_SRT = Path(__file__).resolve().with_name("video_to_srt.py")
+MAX_FILENAME_BYTES = 240
+
+logger = logging.getLogger(__name__)
+
+
+def parse_args() -> tuple[argparse.Namespace, list[str]]:
+    """Parse command-line arguments; unknown options are returned to be forwarded to video_to_srt.py."""
+    parser = argparse.ArgumentParser(
+        description="Download a YouTube video's audio and transcribe it with video_to_srt.py. "
+        "Options not listed here (--model, --speed-up, --language, --chunk-minutes, --api-key, --no-diarize, ...) are passed through.",
+        formatter_class=argparse.ArgumentDefaultsHelpFormatter,
+    )
+    parser.add_argument("video", help="YouTube URL or video id")
+    parser.add_argument("--output-dir", "-d", type=Path, default=Path.cwd(), help="Directory for the SRT file")
+    return parser.parse_known_args()
+
+
+def sanitize(text: str) -> str:
+    """Make text safe for a filename: path separators and other reserved characters become '-', whitespace collapses."""
+    # [\\/:*?"<>|\x00-\x1f] = characters not allowed on common filesystems, plus control characters
+    text = re.sub(r'[\\/:*?"<>|\x00-\x1f]', "-", text)
+    return re.sub(r"\s+", " ", text).strip()
+
+
+def format_date(upload_date: str | None) -> str:
+    """Convert yt-dlp's YYYYMMDD upload date to yyyy-mm-dd ('unknown-date' if missing)."""
+    if not upload_date or len(upload_date) != 8:
+        return "unknown-date"
+    return f"{upload_date[:4]}-{upload_date[4:6]}-{upload_date[6:]}"
+
+
+def build_filename(info: dict) -> str:
+    """Build '<author> -- @<channel> -- <title> -- <yyyy-mm-dd>.srt' from yt-dlp metadata.
+
+    Author is the channel's display name, channel is its @handle (falls back to the channel id).
+    The title is shortened so the whole name stays under MAX_FILENAME_BYTES.
+    """
+    author = sanitize(info.get("uploader") or info.get("channel") or "unknown")
+    handle = (info.get("uploader_id") or info.get("channel_id") or "unknown").lstrip("@")
+    suffix = f" -- @{sanitize(handle)} -- "
+    date = f" -- {format_date(info.get('upload_date'))}.srt"
+    title = sanitize(info.get("title") or info["id"])
+    budget = MAX_FILENAME_BYTES - len(f"{author}{suffix}{date}".encode())
+    while len(title.encode()) > budget:
+        title = title[:-1]
+    return f"{author}{suffix}{title.strip()}{date}"
+
+
+def download_audio(url: str, directory: Path) -> tuple[Path, dict]:
+    """Download the best audio-only stream into `directory`. Returns (file path, yt-dlp metadata)."""
+    options = {"format": "bestaudio/best", "outtmpl": str(directory / "%(id)s.%(ext)s"), "noplaylist": True, "quiet": True}
+    with yt_dlp.YoutubeDL(options) as downloader:
+        info = downloader.extract_info(url, download=True)
+        return Path(downloader.prepare_filename(info)), info
+
+
+def main() -> None:
+    """Download the audio, transcribe it with video_to_srt.py and save the SRT under the metadata-based name."""
+    logging.basicConfig(level=logging.INFO, format="%(asctime)s %(levelname)s: %(message)s")
+    args, forwarded = parse_args()
+    url = args.video if "/" in args.video else f"https://www.youtube.com/watch?v={args.video}"
+    args.output_dir.mkdir(parents=True, exist_ok=True)
+
+    with tempfile.TemporaryDirectory() as temp_directory:
+        audio, info = download_audio(url=url, directory=Path(temp_directory))
+        output = args.output_dir / build_filename(info=info)
+        logger.info("Downloaded %s, writing %s", audio.name, output)
+        subprocess.run([str(VIDEO_TO_SRT), str(audio), "--output", str(output), *forwarded], check=True)
+
+
+if __name__ == "__main__":
+    main()