#!/bin/python3
import os
import sys
import logging
import argparse

from lib import decryption_functs

logging.basicConfig(format='%(levelname)s\t- %(message)s')
logger = logging.getLogger()
logger.setLevel(logging.INFO)

#send to stdout contents of decrypted file
# encrypted file - encryption metadata
def decryptFile(args):

    parser = argparse.ArgumentParser()

    parser.add_argument('encrypted', nargs='?', default=None)
    parser.add_argument('metadata', nargs='?', default=None)

    args = parser.parse_args()

    if len(args) != 2:
        logger.error("Need encrypted file and it's metadata.")
        sys.exit(-1)

    # If first argument is not a file or not found
    if (not os.path.isfile(args.encrypted)):
        logger.error("File '" + args.encrypted + "' not found.")
        sys.exit(-1)

    if (not os.path.isfile(args.metadata)):
        logger.error("File '" + args.metadata + "' not found.")
        sys.exit(-1)

    #Get private key to decrypt
    privateKey = decryption_functs.load_private_key(args.metadata)

    #Decrypt file
    with open(args.encrypted, 'rb') as f:
        content = f.read()

    content = decryption_functs.decrypt_file(privateKey, content)
    
    # Send decrypted content to stdout 
    sys.stdout.write(content)


if __name__ == '__main__':
    decryptFile(sys.argv[1:])