import json
import re
import sys
from pathlib import Path


def parse_wheel_filename(filename):
    """
    Wheel filename から情報を抽出
    例: flash_attn-2.6.3+cu124torch2.5-cp311-cp311-linux_x86_64.whl
        flash_attn-2.7.4+cu124torch2.6-cp311-cp311-linux_x86_64.whl
    """
    # Flash Attention wheelのパターンに合わせて正規表現を調整
    # PyTorchバージョンはパッチバージョンなしの形式 (例: torch2.5)
    pattern = (
        r"flash_attn-(\d+\.\d+\.\d+)\+cu(\d+)torch(\d+\.\d+)-cp(\d+)-cp\d+-(\w+)\.whl"
    )
    match = re.match(pattern, filename)

    if match:
        flash_version = match.group(1)
        cuda_version = f"{match.group(2)[:2]}.{match.group(2)[2:]}"  # 124 -> 12.4
        torch_version = match.group(3)
        python_version = f"{match.group(4)[:1]}.{match.group(4)[1:]}"  # 311 -> 3.11
        platform = match.group(5)  # linux, win32など

        return {
            "flash_version": flash_version,
            "cuda_version": cuda_version,
            "torch_version": torch_version,
            "python_version": python_version,
            "platform": platform,
        }
    return None


def generate_release_notes_from_assets(assets_info: dict):
    assets_names = [
        asset["name"] for asset in assets_info if asset["name"].endswith(".whl")
    ]
    if len(assets_names) == 0:
        sys.exit(1)

    assets_dict = {}

    for asset_name in assets_names:
        asset_info = parse_wheel_filename(asset_name)
        if asset_info is None:
            continue

        if asset_info["platform"] not in assets_dict:
            assets_dict[asset_info["platform"]] = {
                "flash_versions": set(),
                "python_versions": set(),
                "torch_versions": set(),
                "cuda_versions": set(),
            }
        assets_dict[asset_info["platform"]]["flash_versions"].add(
            asset_info["flash_version"]
        )
        assets_dict[asset_info["platform"]]["python_versions"].add(
            asset_info["python_version"]
        )
        assets_dict[asset_info["platform"]]["torch_versions"].add(
            asset_info["torch_version"]
        )
        assets_dict[asset_info["platform"]]["cuda_versions"].add(
            asset_info["cuda_version"]
        )

    notes = []

    for platform_name, data in sorted(assets_dict.items()):
        if any(len(data[key]) == 0 for key in data):
            continue

        platform_name = platform_name[:1].upper() + platform_name[1:]
        platform_name = platform_name.replace("_", " ", 1)

        notes.append(f"## {platform_name}")
        notes.append("")
        notes.append("| Flash-Attention | Python | PyTorch | CUDA |")
        notes.append("| --- | --- | --- | --- |")

        flash_versions = ", ".join(sorted(data["flash_versions"]))
        python_versions = ", ".join(sorted(data["python_versions"]))
        torch_versions = ", ".join(sorted(data["torch_versions"]))
        cuda_versions = ", ".join(sorted(data["cuda_versions"]))

        notes.append(
            f"| {flash_versions} | {python_versions} | {torch_versions} | {cuda_versions} |"
        )
        notes.append("")

    return "\n".join(notes)


def main():
    try:
        if len(sys.argv) != 2:
            sys.exit(1)

        assets_json_path = Path(sys.argv[1])
        if not assets_json_path.exists():
            sys.exit(1)

        with open(assets_json_path, "r") as f:
            assets_info = json.load(f)["assets"]

        if len(assets_info) == 0:
            sys.exit(1)

        text = generate_release_notes_from_assets(assets_info)
        if text:
            print(text)
    except Exception as e:
        print(f"Error: {e}", file=sys.stderr)
        sys.exit(1)


if __name__ == "__main__":
    main()