server.js

const path = require('path') ;
const http = require('http') ; 
const express = require('express') ;
const socketio = require('socket.io') ;
const formatMessage = require('./utils/messages') ; 
const {userJoin,getCurrentUser,userLeaves,getRoomUsers} = require('./utils/users')
const app = express() ;
const server = http.createServer(app);
const io = socketio(server) ;

// Set Static Folder
app.use(express.static(path.join(__dirname,'public'))) ;

const botName = 'Chatcord bot' ;

// Run when client connects 
io.on('connection', socket => {

    socket.on('joinRoom', ({username,room}) => {
        
        const user = userJoin(socket.id , username, room) ;

        socket.join(user.room) ;
        
        // Welcome current user
        socket.emit('message',formatMessage(botName,'Welcome to Realtime Chat App')) ;

        // Broadcast when a user connects
        socket.broadcast.to(user.room).emit('message' , formatMessage(botName,`${user.username} has joined the chat`)) ;


        // Users and Room Info
        io.to(user.room).emit('roomUsers',{
            room: user.room, 
            users: getRoomUsers(user.room)
        }) ;

    });
    
    // Listen for chatMessage
    socket.on('chatMessage', msg => {
        const user = getCurrentUser(socket.id) ;
        io.to(user.room).emit('message',formatMessage(user.username,msg)) ;
    }) ;

    // Runs when client disconnects
    socket.on('disconnect' , () => {
        const user = userLeaves(socket.id) ;
           
        if(user) {
            io.to(user.room).emit('message', formatMessage(botName,`${user.username} has left the chat`)) ;
        }
        
        io.to(user.room).emit('roomUsers',{
            room: user.room, 
            users: getRoomUsers(user.room)
        }) ;
    })
});

const PORT = 3000 || process.env.PORT ;

server.listen(PORT, () => console.log(`Server Running on port ${PORT}`)) ;