from pathlib import Path

import aiofiles


# TODO Add documentation
async def get_current_commit() -> str | None:
    head_path: Path = Path(".git/HEAD")

    if not head_path.exists():
        return None

    async with aiofiles.open(head_path, "r", encoding="utf-8") as head_file:
        head_content: str = (await head_file.read()).strip()

    if not head_content.startswith("ref:"):
        return head_content

    head_ref_path: Path = Path(".git/").joinpath(" ".join(head_content.split(" ")[1:]))

    if not head_ref_path.exists():
        return None

    async with aiofiles.open(head_ref_path, "r", encoding="utf-8") as head_ref_file:
        head_ref_content: str = (await head_ref_file.read()).strip()

    return head_ref_content