#!/usr/bin/env python
#coding: utf-8

"""
Generate an TOTP token (hex value for user.oath file and qrcode).

usage:
gen_otp.py [user [machine [periode [digits]]]]

dependancies:
pip3 install qrcode
"""

import base64
import binascii
import secrets
import sys
import yaml

import qrcode

VAR_FILE = "../group_vars/all/totp.yml"

with open(VAR_FILE) as f:
    VARS = yaml.safe_load(f)

USAGE = "gen_otp.py [user [machine [periode [digits]]]]"
USER = "user"
MACHINE = VARS.get('totp_machine', 'machine')
PERIODE = VARS.get('totp_periode', 60)
DIGITS = VARS.get('totp_digits', 6)

if len(sys.argv) == 2 and sys.argv[1] in ['-h', 'help', '--help']:
    print(USAGE)
    exit(0)
if len(sys.argv) == 5:
    DIGITS = int(sys.argv[4])
if len(sys.argv) >= 4:
    PERIODE = int(sys.argv[3])
if len(sys.argv) >= 3:
    MACHINE = sys.argv[2]
if len(sys.argv) >= 2:
    USER = sys.argv[1]

token = secrets.token_bytes(15)
token_hex = binascii.hexlify(token).decode('utf-8')
token_b32 = base64.b32encode(token).decode('utf-8')
uri = "otpauth://totp/{user}@{machine}?secret={secret}&digits={digits}&period={periode}".format(
    user=USER,
    machine=MACHINE,
    secret=token_b32,
    digits=DIGITS,
    periode=PERIODE)

print("hex:", token_hex)
print("base32:", token_b32)
print("uri:", uri)
qr = qrcode.QRCode()
qr.add_data(uri)
qr.print_ascii(tty=True)