from __future__ import annotations

import logging
import subprocess
import tempfile
from pathlib import Path

logger = logging.getLogger(__name__)

TARGET_SAMPLE_RATE = 48000
TARGET_BITRATE = "64k"
TARGET_FORMAT = "ogg"
TARGET_CODEC = "libopus"


def check_ffmpeg_available() -> bool:
    try:
        result = subprocess.run(["ffmpeg", "-version"], capture_output=True, timeout=5)
        return result.returncode == 0
    except (FileNotFoundError, subprocess.TimeoutExpired):
        return False


def transcode_to_ogg_opus(
    input_data: bytes,
    input_format: str = "mp3",
    sample_rate: int = TARGET_SAMPLE_RATE,
    bitrate: str = TARGET_BITRATE,
) -> bytes | None:
    if not check_ffmpeg_available():
        logger.warning("[FeishuAudio] FFmpeg not available, skipping transcode")
        return None

    with tempfile.NamedTemporaryFile(suffix=f".{input_format}", delete=False) as infile:
        infile.write(input_data)
        input_path = infile.name

    output_path = input_path + f".{TARGET_FORMAT}"

    try:
        cmd = [
            "ffmpeg",
            "-y",
            "-i",
            input_path,
            "-ar",
            str(sample_rate),
            "-b:a",
            bitrate,
            "-c:a",
            TARGET_CODEC,
            output_path,
        ]
        result = subprocess.run(cmd, capture_output=True, timeout=60)
        if result.returncode != 0:
            logger.error(
                "[FeishuAudio] FFmpeg transcode failed: %s",
                result.stderr.decode(errors="replace")[:300],
            )
            return None

        output_bytes = Path(output_path).read_bytes()
        logger.info(
            "[FeishuAudio] Transcode complete: %d -> %d bytes",
            len(input_data),
            len(output_bytes),
        )
        return output_bytes
    except Exception as e:
        logger.error("[FeishuAudio] Transcode error: %s", e)
        return None
    finally:
        Path(input_path).unlink(missing_ok=True)
        Path(output_path).unlink(missing_ok=True)