import json
import os
import subprocess as SP
import sys
import shutil


def get_streams(path):
    proc = SP.Popen(
        [
            "ffprobe",
            "-probesize",
            str(0x7FFFFFFF),
            "-analyzeduration",
            str(0x7FFFFFFF),
            "-v",
            "fatal",
            "-i",
            path,
            "-show_streams",
            "-show_format",
            "-print_format",
            "json",
        ],
        stdout=SP.PIPE,
        stdin=SP.DEVNULL,
        bufsize=0,
    )
    data = json.load(proc.stdout)
    ret = proc.wait()
    if ret != 0:
        return [], {}
    return data["streams"], data["format"]

def ccextract(files):
    ccextractor = shutil.which("ccextractor") or shutil.which("ccextractorwinfull")
    if ccextractor is None and os.name=="nt":
            ccextractor=os.path.expandvars(os.path.join("${PROGRAMFILES(X86)}","CCExtractor","ccextractorwinfull.exe"))
    if not os.path.isfile(ccextractor):
        print("WARNING: CCExtractor not found")
        return []
    new_files=[]
    for file in files:
        outfile=os.path.splitext(file)[0]
        outfile=os.path.extsep.join([outfile, "cc.srt"])
        ret=SP.call([ccextractor, "-sc", "-sbs", "-autodash", "-trim","-nobom","-o", outfile, file])
        if ret==10:
            if os.path.isfile(outfile):
                os.unlink(outfile)
                continue
        new_files.append(outfile)
    return new_files


types = {"mpeg2video": "m2v", "ac3": "ac3", "dvd_subtitle": "sub.mkv", "eia_608": "srt"}

def demux(path):
    folder = os.path.dirname(path)
    basename = os.path.splitext(os.path.basename(path))[0]
    streams, _ = get_streams(path)
    cmd = [
        "ffmpeg",
        "-y",
        "-probesize",
        str(0x7FFFFFFF),
        "-analyzeduration",
        str(0x7FFFFFFF),
        "-i",
        path,
        "-strict",
        "-2",
    ]
    caption_files = []
    for stream in streams:
        codec = stream["codec_name"]
        ext = types.get(codec, codec)
        hex_id = stream["id"]
        codec_name = stream["codec_long_name"]
        outfile = os.path.join(folder, f"{basename}_{hex_id}")
        if codec == "dvd_nav_packet":
            continue
        outfile = os.path.extsep.join([outfile, ext])
        print(hex_id, codec_name, codec)
        if codec == "mpeg2video":
            caption_files.append(outfile)
        cmd += [
            "-map",
            f"0:#{hex_id}",
            "-vcodec",
            "copy",
            "-acodec",
            "copy",
            "-scodec",
            "copy",
            "-strict",
            "-2",
            outfile,
        ]
    SP.check_call(cmd)
    ccextract(caption_files)
    for file in os.listdir(folder):
        if os.path.isfile(file):
            if os.stat(file).st_size==0:
                os.unlink(file)

if __name__ == "__main__":
    demux(sys.argv[1])