index.js

const express = require('express');
const path = require('path');
const http = require('http');
const socketio = require('socket.io');
const Filter = require('bad-words');
const { generateMessage, generateLocationMessage } = require('./src/utils/messages');
const { addUser, removeUser, getUser, getUsersInRoom } = require('./src/utils/users');

const app = express();
const server = http.createServer(app);
const io = socketio(server);

const port = process.env.PORT || 3000;
const publicDirectoryPath = path.join(__dirname, './public');

app.use(express.static(publicDirectoryPath));

//socket.emit => event to specific client
//io.emit => event to every connected client
//socket.broadcast.emit => event to every connected client except current client

//io.to.emit => event to every connected client in same room
//socket.broadcast.io.emit => event every connected client except current client in same room 

io.on('connection', (socket) => {
    console.log('New WebSocket connection');

    socket.on('join', (options, callback) => {
        const {error, user} = addUser({ id: socket.id, ...options});
        if(error) {
            return callback(error);
        }

        socket.join(user.room);

        socket.emit('message', generateMessage('Admin', 'Welcome!'));
        socket.broadcast.to(user.room).emit('message', generateMessage('Admin', `${user.username} has joined!`));
        io.to(user.room).emit('roomData', {
            room: user.room,
            users: getUsersInRoom(user.room)
        });
        
        callback();
    });

    socket.on('sendMessage', (message, callback) => {
        const filter = new Filter();
        if(filter.isProfane(message)) {
            return callback('Profanity is not allowed!')
        }
        const user = getUser(socket.id);
        if(user) {
            io.to(user.room).emit('message', generateMessage(user.username, message));
        }
        callback();
    });

    socket.on('sendLocation', (locationObj, callback) => {
        const {latitude, longitude} = locationObj;
        const user = getUser(socket.id);
        if(user) {
            io.to(user.room).emit('locationMessage', generateLocationMessage(user.username, `https://google.com/maps?q=${latitude},${longitude}`));
        }
        callback();
    });

    socket.on('disconnect', () => {
        const user = removeUser(socket.id);
        if(user) {
            io.to(user.room).emit('message', generateMessage('Admin', `${user.username} has left!`));
            io.to(user.room).emit('roomData', {
                room: user.room,
                users: getUsersInRoom(user.room)
            });
        }
    });
});

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

module.exports = server;