import base64
import binascii
import json
import urllib2
import logging

from hashlib import sha1
from logging.handlers import TimedRotatingFileHandler
from Crypto.Cipher import AES

'''main defines'''
# Silk Prod
#_KEY = binascii.a2b_hex("428f62982c5e1db32d1e9f3b66f75ba9973810eb60c1001e4e581b50cc879fc8")
#_IV = binascii.a2b_hex("29e4c7dc1c6f8cebcf86a04f34725c8f")
#PROVIDER = "silknet"
#LICENSE_SERVER_URL = "https://license.widevine.com/cenc/getlicense"
#ALLOWED_TRACK_TYPES = "SD_HD"

# silk Test
_KEY = binascii.a2b_hex("a3dff872487bdc5c104aa12e90ec1fe40858f56fca8b7b6f1ecd561099993a8c")
_IV = binascii.a2b_hex("73d395265dbcd512dc488e4a532cf00e")
PROVIDER = "silknet"
LICENSE_SERVER_URL = "https://license.uat.widevine.com/cenc/getlicense"
ALLOWED_TRACK_TYPES = "SD_HD"
ALLOW_UNVERIFIED_PLATFORM = True

PARSEFIRST = False

'''logger init'''
log = logging.getLogger('proxy')
log.setLevel(logging.DEBUG)
aFormat = logging.Formatter('[%(asctime)s][%(levelname)s] %(message)s', datefmt='%Y-%m-%d %H:%M:%S')
consoleHandler = logging.StreamHandler()
consoleHandler.setLevel(logging.DEBUG)
consoleHandler.setFormatter(aFormat)
fh = TimedRotatingFileHandler(filename = 'vwproxy.log', when='midnight')
fh.setFormatter(aFormat)
log.addHandler(fh)
log.addHandler(consoleHandler)

'''functions'''
def generateSignature(text_to_sign):
	"""Ingest License Request and Encrypt"""
	try:
		hashed_text = sha1(text_to_sign).digest()
		cipher = AES.new(_KEY, AES.MODE_CBC, _IV)
		padding = binascii.a2b_hex("" if len(hashed_text) % 16 == 0
									else (16 -(len(hashed_text) % 16)) * "00")
		aes_msg = cipher.encrypt(hashed_text + padding)
		signature = base64.b64encode(aes_msg)
		return signature
	except Exception as e:
		log.error('error generating signature' + str(e))
		return -1

def sendRequest(message):
	"""Send HTTP request via urllib2"""
	try:
		f = urllib2.urlopen(LICENSE_SERVER_URL + "/" + PROVIDER, message)
		return f.read()
	except urllib2.HTTPError as e:
		log.error('error in request from WV license server: ' + str(e.errno) + ' | ' + e.message)
		return {'status': -1, 'errno': str(e.errno), 'message': e.message}

def buildCertificateRequest(request):
	"""Builds JSON requests to be sent to the license server."""
	request = json.dumps({'payload': base64.standard_b64encode(request)})
	signature = generateSignature(request)
	if signature:
		certificate_request = json.dumps({"request": base64.standard_b64encode(request),
										"signature": signature,
										"signer": PROVIDER})
		return certificate_request
	else:
		log.error('sigrature error in buildCertificateRequest()')

def parseLicRequest(request):
	# payload = base64.standard_b64encode(request)
	req = json.dumps({
		"payload": base64.standard_b64encode(request),
		"provider": PROVIDER,
		"parse_only": True,
		"allowed_track_types":ALLOWED_TRACK_TYPES,
		"allow_unverified_platform":ALLOW_UNVERIFIED_PLATFORM
	})
	signature = generateSignature(req)
	parseServerRequest = json.dumps({
		"request": base64.standard_b64encode(req),
		"signature": signature,
		"signer": PROVIDER
	})
	# return json.loads(sendRequest(parseServerRequest))
	return json.loads(sendRequest(parseServerRequest))

def buildLicenseRequest(request, haveContentId = False, content_id = 0):
	# payload = base64.standard_b64encode(request)
	reqRaw = {
		"payload": base64.standard_b64encode(request),
		"provider": PROVIDER,
		"allowed_track_types":ALLOWED_TRACK_TYPES,
		"allow_unverified_platform":ALLOW_UNVERIFIED_PLATFORM
	}
	log.debug(reqRaw)
	if haveContentId:
		reqRaw["content_id"] = content_id

	req = json.dumps(reqRaw)

	signature = generateSignature(req)
	parseServerRequest = json.dumps({
		"request": base64.standard_b64encode(req),
		"signature": signature,
		"signer": PROVIDER
	})

	return parseServerRequest

'''kinda' __main__'''
def application(env, start_response):

	log.debug("CONTENT_LENGTH: " + env.get('CONTENT_LENGTH', 0))
	try:
		if env.get('REQUEST_METHOD') == 'OPTIONS':
			log.info('sending OPTIONS')
			start_response('200 OK', [('Content-Type','text/html')])
			return ['OK']
		elif env.get('REQUEST_METHOD') == 'GET' or int(env.get('CONTENT_LENGTH', 0)) < 1: #TODO add other methods in exception
			log.error('got empty request')
			start_response('400', [('Content-Type','text/html')])
			return ['bad request']
		elif int(env.get('CONTENT_LENGTH', 0)) < 50:
			log.info('building certificate request')
			data = env['wsgi.input'].read()
			answer = json.loads(sendRequest(buildCertificateRequest(data)))
			if answer['status'] == 'OK' and answer.has_key('license'):
				#TODO Populate responses
				log.info('sending lic anwser')
				start_response('200 OK', [('Content-Type','text/html')])
				return [base64.standard_b64decode(answer["license"])]
			else:
				start_response('400 Error', [('Content-Type','text/html')])
				return ['go home']
		else:
			log.debug('building license request')

			data = env['wsgi.input'].read()
			print(env['wsgi.input'].read())
			if True:#all(j in env.keys() for j in ['HTTP_X_QRV_CONTENT_ID', 'HTTP_X_QRV_SID']):
				# content_id = env.get('HTTP_X_QRV_CONTENT_ID', 0)
				# SID = env.get('HTTP_X_QRV_SID', 0)
				# log.debug("sid: " + SID + ' ' + "content_id: " + content_id)
				if PARSEFIRST:
					answer = parseLicRequest(data)
					if answer['status'] == 'OK':
						#TODO Populate responses
						log.debug("content_id: " + json.dumps(base64.standard_b64decode(answer["pssh_data"]["content_id"])))
						log.debug(answer["pssh_data"])
						log.debug('client info: ' + json.dumps(answer["client_info"], indent=4))
						answer = json.loads(sendRequest(buildLicenseRequest(data, haveContentId=True, content_id=answer["pssh_data"]["content_id"])))
						if answer['status'] == 'OK' and answer.has_key('license'):
							log.info(answer["license"])
							start_response('200 OK', [('Content-Type','text/html')])
							return [base64.standard_b64decode(answer["license"])]
					else:
						start_response('400 Error', [('Content-Type','text/html')])
						return ['go home']
				else:
					answer = json.loads(sendRequest(buildLicenseRequest(data, haveContentId=False)))
					if answer.has_key('status') and answer['status'] == 'OK' and answer.has_key('license'):
						start_response('200 OK', [('Content-Type','text/html')])
						return [base64.standard_b64decode(answer["license"])]
					else:
						if answer.has_key('status'):
							log.error('request denied. status: ' + answer['status'])
							start_response('500', [('Content-Type','text/html')])
							return ['request error']
						else:
							log.error('request error, no status code')
							start_response('500', [('Content-Type','text/html')])
							return ['request error']
			else:
				log.error('error parsing request header from client.')
				start_response('400', [('Content-Type','text/html')])
				return ['bad request']
	except Exception as e:
		log.error('error: ' + e.message)