from .auth_password_hash_verify_password import parse_stored_hash


def password_needs_rehash(stored: str, iterations: int) -> bool:
    """Was this hash made more weakly than hashes are made today? Call it after
    a successful login and re-hash and save when it answers True."""
    if isinstance(iterations, bool) or not isinstance(iterations, int) or iterations < 1000:
        raise ValueError("iterations must be a whole number of at least 1000")
    stored_iterations, salt, expected = parse_stored_hash(stored)
    return stored_iterations < iterations or len(salt) < 16 or len(expected) != 32