import argparse
import os
import base64
from cryptography.hazmat.primitives.ciphers import Cipher, algorithms, modes
from cryptography.hazmat.primitives import padding


def decrypt_file(encrypted_file_path, output_file_path=None):
    key_Mes = "fb8MH7yIuVUeCp5W4S9cKFtsHaxXIP/zvkO36wNNcO4="
    key = base64.b64decode(key_Mes.encode("ascii"))

    with open(encrypted_file_path, 'rb') as f:
        encrypted_data = f.read()

        cipher = Cipher(
            algorithms.AES(key),
            modes.ECB()
        )

        decryptor = cipher.decryptor()
        padded_data = decryptor.update(encrypted_data) + decryptor.finalize()

        # Remove PKCS7 padding
        unpadder = padding.PKCS7(128).unpadder()
        data = unpadder.update(padded_data) + unpadder.finalize()

        if output_file_path is None:
            output_file_path = encrypted_file_path.replace('.enc', '.dec')
        
        with open(output_file_path, 'wb') as output_file:
            output_file.write(data)
        
        print(f"Decrypted to: {output_file_path}")


def main():
    parser = argparse.ArgumentParser(description='Decrypt file')
    parser.add_argument('-p', '--path', help='Path to encrypted file', required=True)
    parser.add_argument('-o', '--out_file', help='Output file path', default=None)
    args = parser.parse_args()
    return args


if __name__ == '__main__':
    args = main()
    decrypt_file(args.path, args.out_file)