import subprocess
from typing import Optional


def git_head_version(revision: Optional[str] = None, check: bool = True):
    def run_captured(*args):
        res = subprocess.run(
            args,
            stdout=subprocess.PIPE,
            stderr=subprocess.STDOUT,
            text=True,
            check=check,
        )
        return res.stdout

    args = ["git", "describe", "--tags", "--always"]
    if revision:
        args += revision
    vers = run_captured(*args).rstrip()
    if vers.startswith("v") and "." in vers:
        vers = vers[1:]
    if check and not vers:
        raise ValueError(
            "Failed to generate spark version identifier. Please re-run pack_sdk.py with --spark-version <VERSION>"
        )
    return vers