app.js

/*
 * Copyright 2016-present, Facebook, Inc.
 * All rights reserved.
 *
 * This source code is licensed under the license found in the
 * LICENSE file in the root directory of this source tree.
 *
 */

/* jshint node: true, devel: true */
'use strict';

const 
  bodyParser = require('body-parser'),
  config = require('config'),
  crypto = require('crypto'),
  express = require('express'),
  https = require('https'),  
  request = require('request');

var app = express();
var msgs = ['大聲講話啊', '一起踹共啊', '快點打字啊'];

app.set('port', process.env.PORT || 5000);
app.use(bodyParser.json({ verify: verifyRequestSignature }));
app.use(express.static('public'));

/*
 * Be sure to setup your config values before running this code. You can 
 * set them using environment variables or modifying the config file in /config.
 *
 */

// App Secret can be retrieved from the App Dashboard
const APP_SECRET = (process.env.MESSENGER_APP_SECRET) ? 
  process.env.MESSENGER_APP_SECRET :
  config.get('appSecret');

// Arbitrary value used to validate a webhook
const VALIDATION_TOKEN = (process.env.MESSENGER_VALIDATION_TOKEN) ?
  (process.env.MESSENGER_VALIDATION_TOKEN) :
  config.get('validationToken');

// Generate a page access token for your page from the App Dashboard
const PAGE_ACCESS_TOKEN = (process.env.MESSENGER_PAGE_ACCESS_TOKEN) ?
  (process.env.MESSENGER_PAGE_ACCESS_TOKEN) :
  config.get('pageAccessToken');

if (!(APP_SECRET && VALIDATION_TOKEN && PAGE_ACCESS_TOKEN)) {
  console.error("Missing config values");
  process.exit(1);
}

/*
 * Use your own validation token. Check that the token used in the Webhook 
 * setup is the same token used here.
 *
 */
app.get('/webhook', function(req, res) {
  if (req.query['hub.mode'] === 'subscribe' &&
      req.query['hub.verify_token'] === VALIDATION_TOKEN) {
    console.log("Validating webhook");
    res.status(200).send(req.query['hub.challenge']);
  } else {
    console.error("Failed validation. Make sure the validation tokens match.");
    res.sendStatus(403);          
  }
});


/*
 * All callbacks for Messenger are POST-ed. They will be sent to the same
 * webhook. Be sure to subscribe your app to your page to receive callbacks
 * for your page. 
 * https://developers.facebook.com/docs/messenger-platform/implementation#subscribe_app_pages
 *
 */
app.post('/webhook', function (req, res) {

  var data = req.body;

  // Make sure this is a page subscription
  if (data.object == 'page') {
    // Iterate over each entry
    // There may be multiple if batched
    data.entry.forEach(function(pageEntry) {
      var pageID = pageEntry.id;
      var timeOfEvent = pageEntry.time;

      // Iterate over each messaging event
      pageEntry.messaging.forEach(function(messagingEvent) {
        if (messagingEvent.optin) {
          receivedAuthentication(messagingEvent);
        } else if (messagingEvent.message) {
          receivedMessage(messagingEvent);
        } else if (messagingEvent.delivery) {
          receivedDeliveryConfirmation(messagingEvent);
        } else if (messagingEvent.postback) {
          receivedPostback(messagingEvent);
        } else {
          console.log("Webhook received unknown messagingEvent: ", messagingEvent);
        }
      });
    });

    // Assume all went well.
    //
    // You must send back a 200, within 20 seconds, to let us know you've 
    // successfully received the callback. Otherwise, the request will time out.
    res.sendStatus(200);
  }
});

/*
 * Verify that the callback came from Facebook. Using the App Secret from 
 * the App Dashboard, we can verify the signature that is sent with each 
 * callback in the x-hub-signature field, located in the header.
 *
 * https://developers.facebook.com/docs/graph-api/webhooks#setup
 *
 */
function verifyRequestSignature(req, res, buf) {
  var signature = req.headers["x-hub-signature"];

  if (!signature) {
    // For testing, let's log an error. In production, you should throw an 
    // error.
    console.error("Couldn't validate the signature.");
  } else {
    var elements = signature.split('=');
    var method = elements[0];
    var signatureHash = elements[1];

    var expectedHash = crypto.createHmac('sha1', APP_SECRET)
                        .update(buf)
                        .digest('hex');

    if (signatureHash != expectedHash) {
      throw new Error("Couldn't validate the request signature.");
    }
  }
}

/*
 * Authorization Event
 *
 * The value for 'optin.ref' is defined in the entry point. For the "Send to 
 * Messenger" plugin, it is the 'data-ref' field. Read more at 
 * https://developers.facebook.com/docs/messenger-platform/webhook-reference#auth
 *
 */
function receivedAuthentication(event) {
  var senderID = event.sender.id;
  var recipientID = event.recipient.id;
  var timeOfAuth = event.timestamp;

  // The 'ref' field is set in the 'Send to Messenger' plugin, in the 'data-ref'
  // The developer can set this to an arbitrary value to associate the 
  // authentication callback with the 'Send to Messenger' click event. This is
  // a way to do account linking when the user clicks the 'Send to Messenger' 
  // plugin.
  var passThroughParam = event.optin.ref;

  console.log("Received authentication for user %d and page %d with pass " +
    "through param '%s' at %d", senderID, recipientID, passThroughParam, 
    timeOfAuth);

  // When an authentication is received, we'll send a message back to the sender
  // to let them know it was successful.
  sendTextMessage(senderID, "Authentication successful");
}


/*
 * Message Event
 *
 * This event is called when a message is sent to your page. The 'message' 
 * object format can vary depending on the kind of message that was received.
 * Read more at https://developers.facebook.com/docs/messenger-platform/webhook-reference#received_message
 *
 * For this example, we're going to echo any text that we get. If we get some 
 * special keywords ('button', 'generic', 'receipt'), then we'll send back
 * examples of those bubbles to illustrate the special message bubbles we've 
 * created. If we receive a message with an attachment (image, video, audio), 
 * then we'll simply confirm that we've received the attachment.
 * 
 */
function receivedMessage(event) {

  var senderID = event.sender.id;
  var sender = event.sender;
  var recipientID = event.recipient.id;
  var timeOfMessage = event.timestamp;
  var message = event.message;

  var messageText = message.text;
  var messageAttachments = message.attachments;

  if (messageText) {
    gulis(senderID, messageText, 'text');
  } else if (messageAttachments) {
    gulis(senderID, messageAttachments, 'attachments');
  } else {
    // TODO
  }
}


/*
 * Delivery Confirmation Event
 *
 * This event is sent to confirm the delivery of a message. Read more about 
 * these fields at https://developers.facebook.com/docs/messenger-platform/webhook-reference#message_delivery
 *
 */
function receivedDeliveryConfirmation(event) {
  var senderID = event.sender.id;
  var recipientID = event.recipient.id;
  var delivery = event.delivery;
  var messageIDs = delivery.mids;
  var watermark = delivery.watermark;
  var sequenceNumber = delivery.seq;

  if (messageIDs) {
    messageIDs.forEach(function(messageID) {
      console.log("Received delivery confirmation for message ID: %s", 
        messageID);
    });
  }

  console.log("All message before %d were delivered.", watermark);
}


/*
 * Postback Event
 *
 * This event is called when a postback is tapped on a Structured Message. Read
 * more at https://developers.facebook.com/docs/messenger-platform/webhook-reference#postback
 * 
 */
function receivedPostback(event) {
  var senderID = event.sender.id;
  var recipientID = event.recipient.id;
  var timeOfPostback = event.timestamp;

  // The 'payload' param is a developer-defined field which is set in a postback 
  // button for Structured Messages.
  var payload = event.postback.payload;

  console.log("Received postback for user %d and page %d with payload '%s' " + 
    "at %d", senderID, recipientID, payload, timeOfPostback);

  // When a postback is called, we'll send a message back to the sender to 
  // let them know it was successful
  var msg = msgs[Math.floor(Math.random() * msgs.length)];

  sendTextMessage(senderID, '已加入 ' + payload + '，' + msg);
}

/*
 * Send a text message using the Send API.
 *
 */
function sendTextMessage(recipientId, messageText) {
  var messageData = {
    recipient: {
      id: recipientId
    },
    message: {
      text: messageText
    }
  };

  callSendAPI(messageData);
}

/*
 * Call the Send API. The message data goes in the body. If successful, we'll 
 * get the message id in a response 
 *
 */
function callSendAPI(messageData) {
  request({
    uri: 'https://graph.facebook.com/v2.6/me/messages',
    qs: { access_token: PAGE_ACCESS_TOKEN },
    method: 'POST',
    json: messageData

  }, function (error, response, body) {
    if (!error && response.statusCode == 200) {

      var recipientId = body.recipient_id;
      var messageId = body.message_id;

      console.log("Successfully sent generic message with id %s to recipient %s", 
        messageId, recipientId);
    } else {
      console.error("Unable to send message.");
      // console.error(response);
      // console.error(error);
    }
  });  
}

var carousel = [
  {
      title: "統一獅",
      subtitle: "中韓職棒熱身賽－警察廳vs統一獅",
      image_url: "https://i.ytimg.com/vi/pkC6NAvJlCE/hqdefault.jpg",
      buttons: [{
        type: "postback",
        title: "參上",
        payload: "#統一獅",
      }]
  },
  {
      title: "佼心食堂",
      subtitle: "梁家輝、彭于晏",
      image_url: "https://s.yimg.com/uu/api/res/1.2/VWWR2E0ETGDrq8zIFfo3gw--/Zmk9ZmlsbDtweW9mZj0wO3c9MjM0O2g9MTU0O3NtPTE7YXBwaWQ9eXRhY2h5b24-/http://media.zenfs.com/en-US/video/video.pd2upload.com/video.yahootwlive.com@0940b788-2c38-3579-9b7d-2f8aca2652c5_FULL.jpg",
      buttons: [{
        type: "postback",
        title: "參上",
        payload: "#佼心食堂"
      }]
  },
  {
      title: "唐立淇測風向",
      subtitle: "勞工問題效應，還會持續至何時？",
      image_url: "https://s.yimg.com/uu/api/res/1.2/fuJ1wSLEroKuuFzAm1LyQQ--/Zmk9ZmlsbDtweW9mZj0wO3c9MTQ2O2g9ODI7c209MTthcHBpZD15dGFjaHlvbg--/https://media.zenfs.com/creatr-images/GLB/2016-06-27/444747c0-3c93-11e6-a7e7-ed25d9b81d27_snaps-5-about-on-yahoo-legacy_it.jpg",
      buttons: [{
        type: "postback",
        title: "參上",
        payload: "#唐立淇測風向"
      }]
  },
  {
      title: "影音名人堂",
      subtitle: "【雞排炸新聞】相親後被要求卸妝給對方看",
      image_url: "https://s.yimg.com/uu/api/res/1.2/MP8vyb9sINNRuYQNmdy6nA--/Zmk9ZmlsbDtweW9mZj0wO3c9MTQ2O2g9ODI7c209MTthcHBpZD15dGFjaHlvbg--/http://media.zenfs.com/en-US/video/video.pd2upload.com/video.yahooscreen.com@2112bd55-c1ae-35b8-bfaa-816a6381f917_FULL.png",
      buttons: [{
        type: "postback",
        title: "參上",
        payload: "#影音名人堂"
      }]
  }
];

function gulis(recipientId, message, messageType) {

  var uri = 'http://hack.wjhuang.net:3000/bot/index';
  var messageData;

  if (messageType == 'text' && message.indexOf('踹共') === 0) {

    messageData = {
      recipient :{
          id: recipientId
      },
      message: {
        attachment: {
          type: "template",
          payload: {
            template_type: "generic",
            elements: carousel
          }
        }
      }
    };

    callSendAPI(messageData);
  }
  else {
      request.post(uri, {
          form: {
              userid: recipientId,
              message: message || '',
              platform: 'facebook',
              type: messageType,
              user: true
          }
      }, function (error, response, body) {
          // do nothing
      });
  };
}

// Start server
// Webhooks must be available via SSL with a certificate signed by a valid 
// certificate authority.
app.listen(app.get('port'), function() {
  console.log('Node app is running on port', app.get('port'));
});

module.exports = app;