server.js

// Add welcome message
//

var express = require('express');
var bodyParser = require('body-parser');
var app = express();
var server = require('http').createServer(app);
var io = require('socket.io')(server);
var port = process.env.PORT || 3000;

server.listen(port, "0.0.0.0");
console.log('on ', port);

var router = express.Router();

app.get('/', function(req, res){
  res.sendFile(__dirname + '/index.html');
});
app.get('/' + (process.env.ADMIN_ROUTE || 'admin'), function(req, res){
  res.sendFile(__dirname + '/admin.html');
});

router.post('/', function (req, res) {
  if (req.body && req.body.author && req.body.text) {
    messages.push(req.body);
  }
  res.json(req.body);
});

app.use(bodyParser.json());
app.use(function (req, res, next) {
  console.log('req');
  next();
});
app.use(router);


function emit(socket, name, data) {
  console.log('EMITTING', name, data);

  socket.emit('action', Object.assign({}, data, {
    type: name,
  }));
  socket.emit(name, data);
}

function on(socket, name, cb) {
  socket.on(name, cb);
  socket.on('action', (data) => {
    if (data.type === name) {
      cb(data);
    }
  })
}

// Chatroom

// members which are currently connected to the chat
var members = [];
var usernameNum = 0;

io.on('connection', function (socket) {
  console.log('connected!');

  socket.user = {
    username: 'Anonymous',
    created: (new Date).getTime()
  };

  // add the client's username to the global list
  members.push(socket.user);

  emit(socket, 'RECEIVE_MEMBERS', { members });
  emit(socket.broadcast, 'RECEIVE_MEMBERS', { members });
  emit(socket.broadcast, 'MEMBER_JOIN', { user: socket.user });

  // when the client emits 'new message', this listens and executes
  on(socket, 'CREATE_MESSAGE', function (data) {
    var message = data && data.message;

    Object.assign(message, {
      text: message.text,
      author: socket.user || { username: 'Anonymous' },
      date: (new Date).getTime()
    });

    // we tell the client to execute 'new message'
    socket.broadcast.emit('action', { type: 'RECEIVE_MESSAGE', message });
    socket.broadcast.emit('RECEIVE_MESSAGE', { type: 'RECEIVE_MESSAGE', message });
  });

  // when the client emits 'UPDATE_USER', this listens and executes
  on(socket, 'UPDATE_USER', function (event) {
    console.log(event);
    if (!event || !event.user || !event.user.username) {
      return;
    }

    var userUpdate = {
      username: event.user.username
    };

    var oldUser = Object.assign({}, socket.user);
    var user = Object.assign(socket.user, userUpdate);

    emit(socket, 'RECEIVE_USER', { user });
    emit(socket.broadcast, 'USER_UPDATE', { oldUser, user });
    emit(socket, 'RECEIVE_MEMBERS', { members });
    emit(socket.broadcast, 'RECEIVE_MEMBERS', { members });
  });

  on(socket, 'disconnect', function () {
    members = members.filter((user) => {
      return user !== socket.user;
    });

    // echo globally that this client has left
    emit(socket.broadcast, 'MEMBER_LEAVE', { user: socket.user });
    emit(socket.broadcast, 'RECEIVE_MEMBERS', { members });
  });
});