import hashlib
from functools import lru_cache
from pathlib import Path

from flask import url_for


@lru_cache(maxsize=128)
def asset_version(file_path: str) -> str:
    path = Path(file_path)
    if not path.exists():
        return '0'
    return hashlib.md5(path.read_bytes()).hexdigest()[:10]


def asset_url(relative_path: str) -> str:
    base_path = Path(__file__).resolve().parent.parent / 'static' / relative_path
    return url_for('static', filename=relative_path, v=asset_version(str(base_path)))