#!/usr/bin/env python3
"""Extract a paired WildShadow MP4 clip to the frame-folder training layout."""

from __future__ import annotations

import argparse
import subprocess
from pathlib import Path


def extract(video: Path, destination: Path) -> None:
    if not video.is_file():
        raise FileNotFoundError(video)
    destination.mkdir(parents=True, exist_ok=True)
    subprocess.run([
        "ffmpeg", "-hide_banner", "-loglevel", "error", "-y", "-i", str(video),
        "-vsync", "0", "-start_number", "0", str(destination / "rgb_%06d.png"),
    ], check=True)


def main() -> None:
    parser = argparse.ArgumentParser(description=__doc__)
    parser.add_argument("--shadow", required=True, type=Path)
    parser.add_argument("--shadow-free", required=True, type=Path)
    parser.add_argument("--output", required=True, type=Path)
    args = parser.parse_args()
    extract(args.shadow, args.output / "origin")
    extract(args.shadow_free, args.output / "shadow_free")


if __name__ == "__main__":
    main()