import asyncio
import uuid
import os
from pathlib import Path

AUDIO_TMP_DIR = "/tmp/apoena-audio"


async def extract_audio(url: str) -> Path:
    """Download audio-only from a URL using yt-dlp. Returns path to an mp3 temp file."""
    job_id = str(uuid.uuid4())
    outtmpl = f"{AUDIO_TMP_DIR}/{job_id}.%(ext)s"
    expected = Path(f"{AUDIO_TMP_DIR}/{job_id}.mp3")

    cmd = [
        "yt-dlp",
        "--no-warnings",
        "--quiet",
        "--extract-audio",
        "--audio-format", "mp3",
        "--audio-quality", "128K",
        "--format", "bestaudio/best",
        "--output", outtmpl,
        url,
    ]

    proc = await asyncio.create_subprocess_exec(
        *cmd,
        stdout=asyncio.subprocess.PIPE,
        stderr=asyncio.subprocess.PIPE,
    )
    _, stderr = await proc.communicate()

    if proc.returncode != 0:
        raise RuntimeError(stderr.decode().strip() or "yt-dlp failed with no output")

    if expected.exists():
        return expected

    # yt-dlp sometimes keeps the original extension even with --audio-format mp3
    # Find whatever file was created with this job_id prefix
    for f in Path(AUDIO_TMP_DIR).glob(f"{job_id}.*"):
        return f

    raise RuntimeError("yt-dlp produced no output file")