#!/usr/bin/env python

import hashlib
import time

from optparse import OptionParser

# your secret, can be overridden using the --secret parameter.
secret='ADBbUSKOv5WxGCi9yEesRg8u'


parser = OptionParser()
parser.add_option("-d", "--dns-mask", dest="dnsmask",
                  help="DNS mask for content.bitsontherun.com, e.g. 'videos.yoursite.com'")
parser.add_option("-u", "--urlpath", dest="urlpath", help="URL path, e.g. 'videos/a1b2c3d4.mp4'")
parser.add_option("-s", "--secret", dest="secret", help="Your secret key")
parser.add_option("-t", "--timeout", dest="timeout", type="int", help="Timeout, in seconds, from now")

(options, args) = parser.parse_args()

if not options.urlpath:
    parser.error("You need to specify the urlpath parameter")
if options.secret:
    secret = options.secret
if not options.timeout:
    # default timeout is one hour. Usage of smaller timeouts is
    # discouraged.
    options.timeout = 3600

expiry_timestamp = int(time.time()) + options.timeout
sign_data = '%s:%d:%s' % (options.urlpath, expiry_timestamp, secret)
signature = hashlib.md5(sign_data).hexdigest()

print("URL: http://%s/%s?exp=%d&sig=%s" % \
      (options.dnsmask or 'content.bitsontherun.com',
      options.urlpath, expiry_timestamp, signature))