import os
import time
import signal
import sys
from pathlib import Path
from redis import Redis
from rq import Queue

# Config via env (matches docker-compose)
LIB = Path(os.getenv("LIBRARY_ROOT", "/library"))
TRN = Path(os.getenv("TRANSCRIPT_ROOT", "/transcripts"))
REDIS_URL = os.getenv("REDIS_URL", "redis://redis:6379/0")
SCAN_INTERVAL = int(os.getenv("SCAN_INTERVAL", "30"))  # seconds

# Media types to track
MEDIA_EXT = {
    ".mp3", ".m4a", ".mp4", ".mkv", ".wav", ".flac", ".webm", ".ogg", ".opus"
}

# In-memory seen set to avoid re-enqueueing during a single run
_seen: set[str] = set()


def already_transcribed(p: Path) -> bool:
    """Heuristic: if <basename>.json exists in transcripts, consider it done."""
    base_json = TRN / f"{p.stem}.json"
    return base_json.exists()


def iter_media_files(root: Path):
    for path in root.rglob("*"):
        if not path.is_file():
            continue
        if path.suffix.lower() in MEDIA_EXT:
            yield path


def enqueue_new_files():
    q = Queue(connection=Redis.from_url(REDIS_URL))

    # Ensure target dirs exist
    TRN.mkdir(parents=True, exist_ok=True)
    LIB.mkdir(parents=True, exist_ok=True)

    new_jobs = 0
    for p in iter_media_files(LIB):
        key = str(p.resolve())
        if key in _seen:
            continue
        if already_transcribed(p):
            _seen.add(key)
            continue
        # Enqueue the worker to process this local file
        q.enqueue("worker.handle_local_file", key)
        _seen.add(key)
        new_jobs += 1
    return new_jobs


_shutdown = False


def _handle_sig(sig, frame):
    global _shutdown
    _shutdown = True


def main():
    signal.signal(signal.SIGINT, _handle_sig)
    signal.signal(signal.SIGTERM, _handle_sig)

    print(f"[scanner] Watching {LIB} → transcripts in {TRN}; interval={SCAN_INTERVAL}s", flush=True)
    while not _shutdown:
        try:
            jobs = enqueue_new_files()
            if jobs:
                print(f"[scanner] Enqueued {jobs} new file(s)", flush=True)
        except Exception as e:
            print(f"[scanner] Error: {e}", file=sys.stderr, flush=True)
        # Sleep between passes
        for _ in range(SCAN_INTERVAL):
            if _shutdown:
                break
            time.sleep(1)

    print("[scanner] Shutting down", flush=True)


if __name__ == "__main__":
    main()