import websocket,hmac
from websocket import create_connection
from datetime import datetime
import hashlib
import websocket
import json
import struct
import wave
import pickle
import pyaudio

try:
    import thread
except ImportError:
    import _thread as thread
import time
import sig_key

def on_message(ws, message):
    print(message)

def on_error(ws, error):
    print(error)

def on_close(ws):
    print("### closed ###")

def on_open(ws):
    def run(*args):
        for i in range(3):
            time.sleep(1)
            ws.send("Hello %d" % i)
        time.sleep(1)
        ws.close()
        print("thread terminating...")
    thread.start_new_thread(run, ())


# HTTP verb
method = "GET"
# Service name
service = "transcribe"
# AWS Region
region = "us-east-1"
# Amazon Transcribe streaming endpoint
endpoint = "https://transcribe-streaming.us-east-1.amazonaws.com:8443"
# Host
host = "transcribe-streaming.us-east-1.amazonaws.com:8443"
# Date and time of request
amz_date = datetime.now().strftime('%Y%m%dT%H%MZ')#'YYYMMDDTHHMMSSZ'
# Date without time for credential scope
print(amz_date)
datestamp = datetime.now().strftime('%Y%m%d')
canonical_uri = "/stream-transcription-websocket"
canonical_headers = "host:" + host + "\n"
signed_headers = "host"
algorithm = "AWS4-HMAC-SHA256"
access_key = sig_key.access_key
credential_scope = datestamp + "/" + region + "/" + service + "/" + "aws4_request"
canonical_querystring  = "X-Amz-Algorithm=" + algorithm
canonical_querystring += "&X-Amz-Credentials="+ access_key + "/" + credential_scope
canonical_querystring += "&X-Amz-Date=" + amz_date
canonical_querystring += "&X-Amz-Expires=300"
# canonical_querystring += "&X-Amz-Security-Token=" + token
canonical_querystring += "&X-Amz-SignedHeaders=" + signed_headers
canonical_querystring += "&language-code=en-US&media-encoding=pcm&sample-rate=16000"
payload_hash =hashlib.sha256("".encode('utf-8')).hexdigest()
algorithm = 'AWS4-HMAC-SHA256'
print(method)
print(canonical_uri)
print(canonical_querystring)
print(signed_headers)
print(payload_hash)
canonical_request = (method + '\n' + canonical_uri + '\n'
+ canonical_querystring + '\n'
+ canonical_headers + '\n'
+ signed_headers + '\n'
+ payload_hash)

string_to_sign = algorithm + '\n' +  amz_date + '\n' +  credential_scope + '\n' +  hashlib.sha256(canonical_request.encode('utf-8')).hexdigest()

# ************* TASK 3: CALCULATE THE SIGNATURE *************
# Create the signing key using the function defined above.
signing_key = sig_key.getSignatureKey(sig_key.secret_key, datestamp, region, service)

# Sign the string_to_sign using the signing_key
signature = hmac.new(signing_key, (string_to_sign).encode('utf-8'), hashlib.sha256).hexdigest()

canonical_querystring += "&X-Amz-Signature=" + signature
request_url = endpoint + canonical_uri + "?" + canonical_querystring
print(request_url)



if __name__ == "__main__":
    websocket.enableTrace(True)
    ws = websocket.WebSocketApp(request_url.replace('https','wss'),

                              on_message = on_message,
                              on_error = on_error,
                              on_close = on_close)
    ws.on_open = on_open
    ws.run_forever()