app.js

'use strict';

// Modules needed in the app
const express = require('express');
const bodyParser = require('body-parser');
const answers = require('./services/answers-service.js');
const wiki = require('./services/wiki-service.js');

// Creating our main app
var app = express();

// Set the port for our application
// process.env.PORT lets the port be set by Heroku
var port = process.env.PORT || 3000;

// Set the view engine to ejs
app.set('view engine', 'ejs');

// Parse application/x-www-form-urlencoded
app.use(bodyParser.urlencoded({ extended: false }));
// parse application/json
app.use(bodyParser.json());

// Make express look in the public directory for assets (css/js/img)
app.use(express.static(__dirname + '/public'));

// Set the home page route
app.get('/',(req, res) => {
	// Ejs render automatically looks in the views folder
	res.render('index');
});

// GET method route for testing the routes
app.get('/test', (req, res) => {
	// res.send('Hello world, I am a chat bot');
	console.log('▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸', req.query);

	wiki.executeSearch(req.query.criteria, (response) => {
		res.status(200).json(response);
	});
});

// POST method route fot Verify the communication
app.get('/webhook/', (req, res) => {
	if (req.query['hub.verify_token'] === 'my-super-secret') {
		res.send(req.query['hub.challenge']);
	} else {
		res.send('Error, wrong validation token');
	}
});

// For getting the entry messages
app.post('/webhook/', (req, res) => {
	var messaging_events = req.body.entry[0].messaging;

	for (var k = 0; k < messaging_events.length; k++) {
		var event = req.body.entry[0].messaging[k],
			sender = event.sender.id,
			text;

		if (event.message && event.message.text) {
			text = event.message.text;
			// Handle a text message from this sender
			console.log('▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸', text);

			// Let's echo messages back.
			// answers.sendTextMessage(sender, "Text received, echo: " + text.substring(0, 200));

			// Send back a Structured Message if user sends a message "Generic".
			// if (text === 'Generic') {
			// 	answers.sendGenericMessage(sender);

			// 	continue;
			// } else {
			// 	answers.sendTextMessage(sender, "Text received, echo: " + text.substring(0, 200));
			// }
			answers.sendWikiResultMessage(sender, text.substring(0, 50));
		}
		// When the user clicks on a message button or card though, we send back a postback function.
		if (event.postback) {
			text = JSON.stringify(event.postback);

			console.log('▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸▸', text);

			answers.sendTextMessage(sender, "Postback received: " + text.substring(0, 200));
			continue;
		}
	}

	res.sendStatus(200);
});

app.listen(port, () => {
	console.log('Node-Messenger-Bot app is running on http://localhost:' + port);
});