#!/usr/bin/env python3

import argparse
import json
from pathlib import Path

from PIL import Image


def parse_args() -> argparse.Namespace:
    parser = argparse.ArgumentParser(
        description="Convert an image file into a JSON matrix of RGBA pixels."
    )
    parser.add_argument("input_image", type=Path, help="Source image path")
    parser.add_argument("output_json", type=Path, help="Destination JSON path")
    return parser.parse_args()


def image_to_matrix(image_path: Path) -> dict:
    with Image.open(image_path) as image:
        rgba_image = image.convert("RGBA")
        width, height = rgba_image.size
        pixel_map = rgba_image.load()
        rows = [
            [list(pixel_map[x, y]) for x in range(width)]
            for y in range(height)
        ]

    return {
        "source": image_path.name,
        "width": width,
        "height": height,
        "mode": "RGBA",
        "pixels": rows,
    }


def main() -> None:
    args = parse_args()
    data = image_to_matrix(args.input_image)
    args.output_json.parent.mkdir(parents=True, exist_ok=True)
    args.output_json.write_text(json.dumps(data, indent=2), encoding="utf-8")
    print(
        f"Wrote {args.output_json} with {data['width']}x{data['height']} RGBA pixels"
    )


if __name__ == "__main__":
    main()