# Install LINE Python SDK and pyngrok
!pip install line-bot-sdk
!pip install pyngrok

# Import libraries
import json
import requests
from pyngrok import ngrok

from flask import Flask, request, abort
from linebot import LineBotApi, WebhookHandler
from linebot.exceptions import InvalidSignatureError
from linebot.models import MessageEvent, TextMessage, TextSendMessage

# First glance
from transformers import pipeline, Conversation
from transformers import BlenderbotTokenizer, BlenderbotForConditionalGeneration

model = BlenderbotForConditionalGeneration.from_pretrained("facebook/blenderbot-400M-distill")
tokenizer = BlenderbotTokenizer.from_pretrained("facebook/blenderbot-400M-distill")

inputs = tokenizer(["My friends are cool but they eat too many carbs."], return_tensors="pt")
next_reply_ids = model.generate(**inputs)
print("Bot: ", tokenizer.batch_decode(next_reply_ids, skip_special_tokens=True)[0])

# Bot:   That's unfortunate. Are they trying to lose weight or are they just trying to be healthier?

# Build a pipeline
conversational_pipeline = pipeline("conversational", model="facebook/blenderbot-400M-distill")
conversation = Conversation()

# Get response function
def get_response(conversation, sentence):
    conversation.add_user_input(sentence)
    output = conversational_pipeline([conversation])
    return output

# Line Channel ID (DON'T share it with others)
channel_id = "[YOUR_LINE_CHANNEL_ID]"

# Line Channel Secret (DON'T share it with others)
channel_secret = "[YOUR_LINE_CHANNEL_SECRET]"

# Issue a short-term token
def issueToken(client_id, client_secret):
  endpoint = "https://api.line.me/v2/oauth/accessToken"
  header = {'Content-Type': 'application/x-www-form-urlencoded'}
  body = {'grant_type': 'client_credentials',
          'client_id': client_id, 
          'client_secret': client_secret}
  response = requests.post(url=endpoint, data=body, headers=header)
  print(response)
  obj = json.loads(response.text)
  return obj

# Your Line Token (DON'T share it with others)
tokenDict = issueToken(channel_id, channel_secret)

# Assume tokenDict should look like that
# {
# 	'access_token': '[YOUR_LINE_CHANNEL_TOKEN]',
#  	'expires_in': 2592000,
#  	'token_type': 'Bearer'
# }

app = Flask(__name__)
handler = WebhookHandler(channel_secret)
line_bot_api = LineBotApi(tokenDict["access_token"])

@app.route("/callback", methods=['POST'])
def callback():
    signature = request.headers['X-Line-Signature']
    body = request.get_data(as_text=True)

    print("# Webhook event:\n", body)
    print('-'*100)

    # Handle webhook body
    try:
        handler.handle(body, signature)
    except InvalidSignatureError:
        print("Invalid signature. Please check your channel access token/channel secret.")
        abort(400)

    return "OK"

@handler.add(MessageEvent, message=TextMessage)
def handle_message(event):
    print(f"Message Return: {event}")
    line_bot_api.reply_message(event.reply_token, TextSendMessage(text=event.message.text.strip()))

# Ngrok configuration
!ngrok authtoken 2EkXz20Sxld1yr6MDyEw3wGe8FG_7E5Nh1H6fH1AHCHVdVCAw
!cat /root/.ngrok2/ngrok.yml

# Setting up http tunnel
http_tunnel = ngrok.connect(5000)
print(http_tunnel)

def setWebhook(endpoint, CHANNEL_ACCESS_TOKEN):
    endpointFixed = f"https://{endpoint.split('//')[-1]}/callback"
    url = "https://api.line.me/v2/bot/channel/webhook/endpoint"
    header = {'Content-Type': 'application/json', 'Authorization': 'Bearer ' + CHANNEL_ACCESS_TOKEN}
    body = json.dumps({'endpoint': endpointFixed})
    response = requests.put(url=url, data=body, headers=header)
    print(response)

setWebhook(http_tunnel.public_url, channelAccessToken)