Communications for chat client using message.socket.io

client.js

var ChatRoom = function ChatRoom(chatList, inputArea, list) {
	var _chatList = chatList,
		_inputText = inputArea,
		_userList = list,
		_nickList = [];
		
	/*
	 * Handle three events from the communications layer 
	 */
	this.expose = {
		'joined': {
			'eventHandler': '__api__joined'
		},
		'left': {
			'eventHandler': '__api__left'
		},
		'said': {
			'eventHandler': '__api__said'
		}
	};
	
	this.__api__joined = function __api__joined(comInstance, args) {
		this._addMetaLine(args['nick'] + " joined");
		this.addUser(args['nick']);
	}
	
	this.__api__left = function __api__left(comInstance, args) {
		this._addMetaLine(args['nick'] + " left");
		this.delUser(args['nick']);
	}
	
	this.__api__said = function __api__said(comInstance, args) {
		this._addChat(args['nick'], args['text']);
	}
	
	this.addUser = function addUser(nick) {
		_nickList.push(nick);
		this._addUserHTML(nick);
	}
	
	this.delUser = function delUser(nick) {
		/*
		 * Remove the user from our user list
		 */
		for(var i = 0, max = _nickList.length; i < max; i++) {
			if(nick === _nickList[i]) {
				arrayRemove(_nickList, i);
				break;
			}
		}
		
		/*
		 * Rebuild the user list html entity
		 */
		_userList.innerHTML = '';
		
		for(var i = 0, max = _nickList.length; i < max; i++) {
			this._addUserHTML(_nickList[i]);	
		}
	}
	
	this._addChat = function addChat(nick, text) {
		this._addLine(nick + ": " + text);
	}
	this._addLine = function addLine(chatText) {
		_chatList.innerHTML += "<li class='chat'>" + chatText + "</li>";
		_chatList.scrollTop = _chatList.scrollHeight;
	}
	
	this._addMetaLine = function addMetaLine(text) {
		_chatList.innerHTML += "<li class='meta'>" + text + "</li>";
		_chatList.scrollTop = _chatList.scrollHeight;
	}
	
	this._addUserHTML = function addUserHTML(nick) {
		_userList.innerHTML += "<li>" + nick + "</li>";
	}
}

server.js

ChatRoom = function ChatRoom() {
	/*
	 * Expose two functions to the communications layer, joining and talking
	 */ 
	this.expose = {
		'say': {
			'function': '__api__say'
		},
		'join': {
			'function': '__api__join'
		}
	};
	
	this.nickList = [];
	this.clients = [];
	this.chatLines = [];
}

ChatRoom.prototype.__proto__ = EventEmitter.prototype;

ChatRoom.prototype.__api__say = function __api__say(comInstance, args, callback) {
	var text = args.text,
		nick,
		lineObj;
		
	if(undefined === text) {
		callback(new Error("Client did not say shit"));
	}
	else {
		nick = this.clients[comInstance.getInstanceId()];
		
		lineObj = {'nick': nick, 'text': text};
		this.chatLines.push(lineObj);
		
		callback(null, {});
		
		this.emit('said', 'room', lineObj);
	}
}

ChatRoom.prototype.__api__join = function __api__join(comInstance, args, callback) {
	var nick = args.nick;
		
	if(undefined === nick) {
		callback(new Error("Client did not specify nickname"));
	}
	else if(!this.isNickAvailable(nick)) {
		callback(new Error("Nickname is already in use"));
	}
	else {
		this.clients[comInstance.getInstanceId()] = nick;
		
		comInstance.subscribeObject(this, 'joined');
		comInstance.subscribeObject(this, 'left');
		comInstance.subscribeObject(this, 'said');
		
		callback(null, {'users': this.nickList, history: this.chatLines.slice(-10)});
		
		this.emit('joined', 'room', {'nick': nick});
		
		this.nickList.push(nick);
	}
}