#!/usr/bin/env python3

import argparse
import struct
import subprocess
from pathlib import Path


def main() -> int:
    parser = argparse.ArgumentParser(description="Convert a GC menu DDS jacket to PSP RGBA4444")
    parser.add_argument("input_dds")
    parser.add_argument("output_orpj")
    args = parser.parse_args()

    command = [
        "ffmpeg", "-hide_banner", "-loglevel", "error", "-i", args.input_dds,
        "-vf", "crop=197:197:0:0,scale=128:128:flags=lanczos",
        "-frames:v", "1", "-f", "rawvideo", "-pix_fmt", "rgba", "-",
    ]
    result = subprocess.run(command, stdout=subprocess.PIPE, check=False)
    expected = 128 * 128 * 4
    if result.returncode != 0 or len(result.stdout) != expected:
        raise SystemExit(f"ffmpeg produced {len(result.stdout)} bytes, expected {expected}")

    pixels = bytearray(128 * 128 * 2)
    for index in range(128 * 128):
        r, g, b, a = result.stdout[index * 4:index * 4 + 4]
        value = (r >> 4) | ((g >> 4) << 4) | ((b >> 4) << 8) | ((a >> 4) << 12)
        struct.pack_into("<H", pixels, index * 2, value)

    output = Path(args.output_orpj)
    output.parent.mkdir(parents=True, exist_ok=True)
    header = struct.pack("<4sHHHHI", b"ORPJ", 1, 128, 128, 0, len(pixels))
    output.write_bytes(header + pixels)
    return 0


if __name__ == "__main__":
    raise SystemExit(main())