import subprocess
from pathlib import Path


def convert_mp4_to_wav(
        input_mp4: str,
        ffmpeg_path: str = r"d:\ffmpeg\ffmpeg.exe",
        output_path: str = None  # 新增输出路径参数
):
    """
    将指定MP4文件转换为WAV格式
    参数：
    input_mp4 - 输入的MP4文件路径
    ffmpeg_path - FFmpeg可执行文件路径
    output_path - 可选输出路径（可指定完整路径或目录）
    """
    input_path = Path(input_mp4)

    # 处理输出路径逻辑
    if output_path:
        output_path = Path(output_path)
        if output_path.is_dir():  # 如果传入的是目录
            output_path = output_path / f"{input_path.stem}.wav"
        output_path.parent.mkdir(parents=True, exist_ok=True)
    else:
        # 默认输出到wav目录
        output_dir = Path("wav")
        output_dir.mkdir(exist_ok=True)
        output_path = output_dir / f"{input_path.stem}.wav"

    cmd = [
        ffmpeg_path,
        "-i", str(input_path),
        "-acodec", "pcm_s16le",
        "-ac", "1",
        "-ar", "16000",
        "-y",
        str(output_path)  # 使用处理后的输出路径
    ]

    try:
        # 执行转换命令
        subprocess.run(cmd, check=True, capture_output=True)
        print(f"转换成功：{input_path} -> {output_path}")
    except subprocess.CalledProcessError as e:
        print(f"转换失败：{e.stderr.decode('gbk')}")
    except FileNotFoundError:
        print(f"FFmpeg未找到，请确认路径是否正确：{ffmpeg_path}")