#!/usr/bin/env python3

'''
This script will perform a simple query to the DarkOwl Vision Test API.
A succesfull call will print {'answer': 'hoot'}
'''


import requests
import datetime
import hmac
import hashlib
import base64

publicKey = 'PUBLIC_KEY_HERE'
privateKey = 'PRIVATE_KEY_HERE'


def main():
    perform_query()

def perform_query():
    host = 'api.darkowl.com'
    endpoint = '/api/v1/test'

    url = f'https://{host}{endpoint}'

    date = datetime.datetime.utcnow().strftime('%a, %d %b %Y %H:%M:%S GMT')

    auth = generate_auth_header(endpoint, 'GET', privateKey, publicKey, date)
    headers = {'Authorization': auth, 'X-VISION-DATE': date, 'Accept': 'application/json'}
    r = requests.get(url, headers=headers)
    if r.status_code == 200:
        print(r.json())
    else:
        print(r.content)
        exit(1)

def generate_auth_header(abs_path,
                         http_method,
                         private_key,
                         public_key,
                         time_stamp):

    string2hash = http_method + abs_path + time_stamp
    bkey = bytes(source=private_key, encoding='UTF-8')
    bpayload = bytes(source=string2hash, encoding='UTF-8')
    hmacsha1 = hmac.new(bkey, bpayload, hashlib.sha1).digest()
    base64encoded = base64.b64encode(hmacsha1).decode('UTF-8')
    auth_header = f'OWL {public_key}:{base64encoded}'
    return auth_header

if __name__ == '__main__':
    main()