#!/usr/bin/env python3
# -*- coding: utf-8 -*-

import sys
import os

import requests
from requests.structures import CaseInsensitiveDict
import json

from time import sleep


# set transcription service API endpoint and token (retrieved from operating system's ENV variables)
#   + sample endpoints:
#       - [dev]     "https://development.sendpotion.com/api/transcript"
#       - [staging] "https://staging.sendpotion.com/api/transcript"
API_ENDPOINT = os.environ.get("TRANSCRIPTION_API_ENDPOINT")
API_TOKEN = os.environ.get("TRANSCRIPTION_API_TOKEN")


#
# Using potions internal transcription API endpoint, get a transcription for a given (wav) audio recording
#   + returns a triple:
#       - Boolean ......... indicating success (True) or failure (False)
#       - String / None ... transcription text (or None in failure case)
#       - Float / None .... transcription confidence score (or None in failure case)
#
def get_transcription(wav_fname):

    # validate that transcription service API endpoint and token are set
    if (API_ENDPOINT is None) or (API_TOKEN is None):
        # terminate
        print("TRANSCRIPTION_API_ENDPOINT and TRANSCRIPTION_API_TOKEN environment variables MUST be set!")
        sys.exit(1)

    # set request header to contain (bearer) API token
    headers = CaseInsensitiveDict()
    headers["Accept"] = "application/json"
    headers["Authorization"] = "Bearer " + str(API_TOKEN)

    # set files field (data is empty)
    files = {'wav': open(wav_fname, 'rb')}

    # issue POST request and save response as response object
    response = requests.post(url = API_ENDPOINT, headers = headers, files = files)

    # test for auth error
    # test for timeout

    # check if the status code is not an error code (i.e., 4xx or 5xx)
    success = False
    if response:
        # extracting response text 
        response_text = response.text
        response_json = json.loads(response_text)
        #print(response_json)

        if response.ok:   # synch call
            success = True
            trans_text = response_json["transcriptObj"]["text"]
            trans_score = float(response_json["transcriptObj"]["confidence"])
        else:             # fallback to asynch call
            # wait up to 60 seconds for the transcription to be ready; try every 5 seconds
            wait = 0

            while wait < 60:
                sleep(5)
                wait += 5

                # issue GET request using the previously returned reqiestId and save response as response object
                response_get = requests.get(url = API_ENDPOINT + ':' + response_json["requestId"])

                # check if the status code is not an error code (i.e., 4xx or 5xx)
                if response_get.ok:
                    response_get_text = response_get.text
                    response_get_json = json.loads(response_get_text)

                    success = True
                    trans_text = response_get_json["transcriptObj"]["text"]
                    trans_score = float(response_get_json["transcriptObj"]["confidence"])
                    break

            # in case no successful response is received even after a 60 seconds waiting period -> proceed without transcription
            #if not response_get.ok:
            #    print("Response: FAILED.")

    #else:
    #    print("ERROR: {} ({})" . format(response.status_code, response.text))

    if success:
        return success, trans_text, trans_score
    else:
        return False, None, None