nodejs simple chat server used@cacodaemon.de

server.js

var net = require('net');

function Clients () {
    var clients = new Array()
    var clientCounter = 0

    var Client = function (socket, name) {
        this.send = function(msg) {
            this.socket.write(msg + '\n')
        }

        this.toString = function() {
            return this.name
        }

        this.socket = socket
        this.name = name
        this.send('Hello, use /help to display available commands.')
    }

    var getClientBySocket = function(socket) {
        for (var i = clients.length - 1; i >= 0; i--) {
            if (clients[i].socket == socket) {
                return clients[i]
            }
        }
        return null
    }

    var getClientByname = function(name) {
        for (var i = clients.length - 1; i >= 0; i--) {
            if (clients[i].name == name) {
                return clients[i]
            }
        }
        return null
    }

    this.addClient = function (socket) {
        var client = new Client(socket, 'User_' + ++clientCounter)
        this.sendToAll('New user logged in.')
        clients.push(client)
        return client
    }

    this.sendToAll = function (msg) {
        for (var i = clients.length - 1; i >= 0; i--) {
            if (!clients[i]) {
                continue
            }
            clients[i].send(msg)
        }
    }

    this.sendToAllFromClient = function (msg, socket) {
        var client = getClientBySocket(socket)

        for (var i = clients.length - 1; i >= 0; i--) {
            if (!clients[i]) {
                continue
            }
            if (clients[i].socket == client.socket) {
                continue
            }
            clients[i].send(client + ': ' + msg)
        }
    }

    this.removeClient = function (socket) {
        for (var i = clients.length - 1; i >= 0; i--) {
            if (clients[i].socket != socket) {
                continue
            }
            clients.splice(i)
            return
        }
    }

    this.handleCommand = function (command, socket) {
        var client = getClientBySocket(socket)

        if (command.substring(0, 1) != '/') { //check is command
            return false
        }

        command = command.split(' ')
        var type = command[0]
        var value = command.length > 1 ? command[1] : null

        switch (type) {
            case '/name':
                this.sendToAll(client.name + ' changed his name to ' + value)
                client.name = value
                break
            case '/kick':
                var cmdClient = getClientByname(value)

                if (cmdClient == null) {
                    client.send('User not found!')
                    return
                }

                this.removeClient(cmdClient.socket)
                cmdClient.socket.end()
                break
            case '/quit':
                this.removeClient(socket)
                socket.end()
                break
            case '/private':
                var cmdClient = getClientByname(value)

                if (cmdClient == null) {
                    client.send('User not found!')
                    return
                }      

                var message = command.splice(2, command.length).join(' ')
                cmdClient.send(client + ' sends you a private message: ' + message)     

                break
            case '/users':
                var users = 'Users online: ' + clients.join(', ')
                client.send(users)
                break
            default:
                client.send('Unkown command: ' + type)
            case '/help':
                client.send('Available commands are:' + 
                    '/name <YouNewName>, ' +
                    '/kick <UserName>, ' +
                    '/private <UserName> <your private message>, ' +
                    '/quit, ' +
                    '/users, ' +
                    '/help')
                break
        }
        return true
    }
}

var clients = new Clients();

net.createServer(function (socket) {
	clients.addClient(socket)

 	socket.on('data', function(msgBuffer) {
        var msg = msgBuffer.toString()
        msg = msg.substring(0, msg.length - 1) //remove newline
        console.log(msg)

        if (clients.handleCommand(msg, socket)) {
            return
        }
        clients.sendToAllFromClient(msg, socket)
    });

    socket.on('end', function() {
        clients.removeClient(socket)
    });
}).listen(1337);