#
# Requirements: argon2-cffi
#

import argon2
import argparse
import getpass
import sys

#
# WARNING: Changing any of the parameters below will affect password generation
#

# Default SALT to use; this cannot be random since passgeny must
# generate predictable passwords
PASSGENY_SALT_DEFAULT = b"Passgeny v1"
# Memory cost expresssed in kb
PASSGENY_ARGON2_MEMORY_COST = 8192
# Number of iterations
PASSGENY_ARGON2_TIME_COST = 6
# Number of parallel threads
PASSGENY_ARGON2_PARALLEL = 4
# Hash length - 512 bits by default
PASSGENY_ARGON2_HASH_LEN = 64

def argon2_hash(message):
    return argon2.low_level.hash_secret_raw(
            message,
            PASSGENY_SALT_DEFAULT,
            type = argon2.Type.ID,
            memory_cost = PASSGENY_ARGON2_MEMORY_COST,
            time_cost = PASSGENY_ARGON2_TIME_COST,
            parallelism = PASSGENY_ARGON2_PARALLEL,
            hash_len = PASSGENY_ARGON2_HASH_LEN)

def passgeny_hash(master_password, token_list):
    message = b''

    # Construct the message to be hashed
    for x in token_list:
        message += x.encode() + b'\0'

    message += master_password.encode() + b'\0'
    return argon2_hash(message)

mpw = getpass.getpass("Master password: ")
print(passgeny_hash(mpw, ("1", "2", "3")))