"""Helpers for cryptography."""

from Crypto.Hash import SHA
from Crypto.PublicKey import RSA
from Crypto.Signature import pkcs1_15


def verify_signature(public_key_data: bytes, signature: bytes, data: bytes) -> bool:
    """Verify that the data was signed correctly.

    Args:
        public_key_data (bytes): Public key data
        signature (bytes): Signature to compare against
        data (bytes): Data which was signed

    Returns:
        bool: whether the signature is valid
    """
    key = RSA.import_key(public_key_data)
    digest = SHA.new(data)  # type: ignore
    signer = pkcs1_15.new(key)

    try:
        signer.verify(digest, signature)
        return True

    except (ValueError, TypeError):
        return False