#!/usr/bin/env python3
from __future__ import annotations

import argparse
import re
from pathlib import Path
from zipfile import ZIP_DEFLATED, ZipFile


IMAGE_ID_RE = re.compile(r"(?:_e)?_(\d+)\.[^.]+$")


def image_sort_key(path: Path) -> tuple[int, str]:
    match = IMAGE_ID_RE.search(path.name)
    if match:
        return int(match.group(1)), path.name
    return 10**12, path.name


def collect_first_n_images(img_dir: Path, limit: int) -> list[Path]:
    images = [p for p in img_dir.iterdir() if p.is_file() and IMAGE_ID_RE.search(p.name)]
    return sorted(images, key=image_sort_key)[:limit]


def build_zip(dataset_root: Path, output_zip: Path, image_limit: int) -> None:
    with ZipFile(output_zip, "w", compression=ZIP_DEFLATED) as zf:
        readme = dataset_root / "README.md"
        if readme.exists():
            zf.write(readme, readme.relative_to(dataset_root))

        puzzle_type_info = dataset_root / "puzzle_type_info.csv"
        if puzzle_type_info.exists():
            zf.write(puzzle_type_info, puzzle_type_info.relative_to(dataset_root))

        smart_data_dir = dataset_root / "SMART101-Data"
        for puzzle_dir in sorted(
            [p for p in smart_data_dir.iterdir() if p.is_dir()],
            key=lambda p: int(p.name),
        ):
            csv_files = sorted(puzzle_dir.glob("*.csv"))
            for csv_file in csv_files:
                zf.write(csv_file, csv_file.relative_to(dataset_root))

            img_dir = puzzle_dir / "img"
            if not img_dir.exists():
                continue

            for image_path in collect_first_n_images(img_dir, image_limit):
                zf.write(image_path, image_path.relative_to(dataset_root))


def main() -> None:
    parser = argparse.ArgumentParser(
        description="Create a SMART101 zip archive with all CSVs and only the first N images per img directory."
    )
    parser.add_argument(
        "--dataset-root",
        type=Path,
        default=Path(__file__).resolve().parent,
        help="Path containing README.md, puzzle_type_info.csv, and SMART101-Data/.",
    )
    parser.add_argument(
        "--output",
        type=Path,
        default=Path("SMART101-first20-images.zip"),
        help="Output zip file path.",
    )
    parser.add_argument(
        "--image-limit",
        type=int,
        default=20,
        help="Number of images to keep from each img directory.",
    )
    args = parser.parse_args()

    dataset_root = args.dataset_root.resolve()
    output_zip = args.output.resolve()
    output_zip.parent.mkdir(parents=True, exist_ok=True)

    build_zip(dataset_root, output_zip, args.image_limit)
    print(f"Created {output_zip}")


if __name__ == "__main__":
    main()