// dialogflow
const dialogflow = require('dialogflow');

// server and websocket
const WebSocket = require('ws');
const http = require('http');
const path = require('path');
const express = require('express');

const webSocketsServerPort = 8000;
const serverpath = '/ws';
const app = express();
const router = express.Router();

router.get('/', function (req, res) {
  res.sendFile(path.join(__dirname + '/index.html'));
});

app.use(express.static(__dirname + '/../client'));

app.use('/', router);

var server = http.createServer(app);

server.listen(process.env.port || webSocketsServerPort, function () {
  console.log((new Date()) + ' Server is listening on port ' +
        webSocketsServerPort);
});

const wss = new WebSocket.Server({ server: server, path: serverpath });

wss.on('connection', function connection (ws) {
  ws.id = wss.getUniqueID();

  console.log(ws.id + ' connected');

  ws.on('message', function incoming (message) {
    promptQuery(message, ws);
  });

  ws.on('close', function (connection) {
    // close user connection
  });
});

const projectId = 'digitalerdemenztest';

const sessionClient = new dialogflow.SessionsClient({
  keyFilename: 'dialogflow_cred_dem.json'
});

// Send request and log result
function promptQuery (prompt, wsock) {
  let sessionId = wsock.id;
  let sessionPath = sessionClient.sessionPath(projectId, sessionId);

  const request = {
    session: sessionPath,
    queryInput: {
      text: {
        text: prompt,
        languageCode: 'de-DE'
      }
    }
  };

  sessionClient
    .detectIntent(request)
    .then(responses => {
      const result = responses[0].queryResult;
      console.log(`  Query: ${result.queryText}`);
      console.log(`  Response: ${result.fulfillmentText}`);
      if (result.intent) {
        console.log(`  Intent: ${result.intent.displayName}`);
      } else {
        console.log(`  No intent matched.`);
      }
      wsock.send(JSON.stringify(result));

      // checkIntent(result)
    })
    .catch(err => {
      console.error('ERROR:', err);
    });
}

// create unique id
wss.getUniqueID = function () {
  function s4 () {
    return Math.floor((1 + Math.random()) * 0x10000).toString(16).substring(1);
  }
  return s4() + s4() + '-' + s4();
};