quiz.js

var states = {START:0,TEST_QUESTION:1,STARTING:2,SHOW_QUESTION:3,SHOW_ANSWER:4,END:5};

function Quizzes(){
	var quizzes = {};

	this.loadAll = function(){
		var files = fs.readdirSync('./quizzes');

		for(var f in files){
			try{
				var quizId = files[f];
				var path = ('./quizzes/'+quizId+'/questions.txt');
				var contentPath = 'content/'+quizId+'/';

				if(fs.existsSync(path)){
					console.log("# Loading Quiz: "+quizId);
					var quiz = new Quiz(quizId);
					var currentQuestion = false;

					var content = fs.readFileSync(path,'utf8');
					var i = 0;
					while (i < content.length)
					{
						var j = content.indexOf("\n", i);
						if (j == -1) j = content.length;
						var line = content.substr(i, j-i);
						line = line.replace("\r","");

						var sTitle = "title ";
						var sQuestion = "q ";
						var sAnswer = "a ";
						var sCorrectAnswer = "ac ";
						var sImg = "img ";
						var sQuestionEnd = "!";
						var sAdminCode = "admincode ";
						var sQuizCode = "quizcode ";
						var sTime = "time ";
						var sMarks = "marks ";

						if(line == sQuestionEnd){
							if(currentQuestion){
								quiz.addQuestion(currentQuestion);
							}
						}
						else if(line.startsWith(sTitle)){
							quiz.setTitle(line.substr(sTitle.length));
						}
						else if(line.startsWith(sImg)){
							if(!currentQuestion){
								quiz.setPic(contentPath  + line.substr(sImg.length));
							}
							else{
								currentQuestion.setPic(contentPath + line.substr(sImg.length));
							}
						}
						else if(line.startsWith(sAnswer)){
							if(currentQuestion){
								currentQuestion.addAnswer(line.substr(sAnswer.length));
							}
						}
						else if(line.startsWith(sCorrectAnswer)){
							if(currentQuestion){
								currentQuestion.addCorrectAnswer(line.substr(sCorrectAnswer.length));
							}
						}
						else if(line.startsWith(sQuestion)){
							currentQuestion = new Question();
							currentQuestion.setQuestion(line.substr(sQuestion.length));
						}
						else if(line.startsWith(sAdminCode)){
							quiz.setAdminCode(line.substr(sAdminCode.length));
						}
						else if(line.startsWith(sQuizCode)){
							quiz.setQuizCode(line.substr(sQuizCode.length));
						}
						else if(line.startsWith(sTime)){
							try {
								if(currentQuestion) currentQuestion.setTime(parseInt(line.substr(sTime.length)));
							}
							catch (e) {
							  console.log("# Invalid time: "+line);
							}
						}
						else if(line.startsWith(sMarks)){
							try {
								if(currentQuestion) currentQuestion.setMarks(parseInt(line.substr(sMarks.length)));
							}
							catch (e) {
							  console.log("# Invalid marks: "+line);
							}
						}

						i = j+1;
					}

					quizzes[quizId] = quiz;
					quiz.ready();
				}
			}
			catch(e){
				console.log(e);
				console.trace();
			}
		}
	}

	this.getList = function(){
		var result = [];
		for(var q in quizzes){
			result.push({quiz: q,link: '/quiz/'+q});
		}

		return result;
	}

	this.addParticipant = function(participant){
		var quizId = participant.getQuizId();
		if(quizId in quizzes)
		quizzes[quizId].addParticipant(participant);
	}

	this.isValidQuizId = function(quizId){
		if(typeof quizId === 'undefined') return false;
		if(quizId in quizzes) return true;
		return false;
	}

	this.isValidTeamname = function(quizId,teamname){
		if(quizId in quizzes)
		return quizzes[quizId].isValidTeamname(teamname);
	}

	this.getQuizDetails = function(quizId){
		if(quizId in quizzes)
		return quizzes[quizId].getDetails();
	}

	this.isValidQuizCode = function (quizId,quizCode){
		if(quizId in quizzes)
		return quizzes[quizId].isValidQuizCode(quizCode);
	}

	this.isValidAdminPassword = function(quizId,adminPassword){
		if(quizId in quizzes)
		return quizzes[quizId].isValidAdminPassword(adminPassword);
	}

	this.sendUpdates = function(participant){
		var quizId = participant.getQuizId();
		if(quizId in quizzes)
		quizzes[quizId].sendUpdates(participant);
	}

	this.getParticipant = function(quizId,participantId){
		if(quizId in quizzes)
		return quizzes[quizId].getParticipant(participantId);
	}

	this.startQuiz = function(quizId){
		if(quizId in quizzes)
		quizzes[quizId].startQuiz();
	}

	this.endQuiz = function(quizId){
		if(quizId in quizzes)
		quizzes[quizId].endQuiz();
	}

	this.showTestQuestion = function(quizId){
		if(quizId in quizzes)
		quizzes[quizId].showTestQuestion();
	}

	this.showNextQuestion = function(quizId){
		if(quizId in quizzes)
		quizzes[quizId].nextQuestion();
	}

	this.collectResponse = function(quizId,participant,response){
		if(quizId in quizzes)
		quizzes[quizId].collectResponse(participant,response);
	}

	this.cancelLastQuestion = function(quizId){
		if(quizId in quizzes)
		quizzes[quizId].cancelLastQuestion();
	}

	this.getLeaderboard = function(quizId){
		if(quizId in quizzes)
		return quizzes[quizId].getLeaderboard();
	}

	this.loadAll();
}

function Participants(){
	var participants = {};
	var teamnames = {};
	var leaderboard = new Leaderboard();

	this.addParticipant = function(participant){
		var uniqueId = participant.getUniqueId();
		if(typeof uniqueId === 'undefined' || !uniqueId) return;

		participants[uniqueId] = participant;

		if(participant.isRealParticipant){
			teamnames[participant.getTeamname()] = true;
			this.updateRanks();
		}
	}

	this.getParticipant = function(participantId){
		if(participantId in participants)
			return participants[participantId];
		else
			return false;
	}

	this.removeParticipant = function(uniqueId){
		if(uniqueId in participants)
			delete participants[uniqueId];
	}

	this.isValidTeamname = function(teamname){
		if(teamname.length<=3) return false;
		if(teamname in teamnames) return false;
		return true;
	}

	this.getAll = function(){
		return participants;
	}

	this.resetResponses = function(){
		for(var id in participants){
			if(participants[id] && participants[id].isRealParticipant){
				participants[id].resetResponse();
			}
		}
	}

	this.resetScores = function(){
		for(var id in participants){
			if(participants[id] && participants[id].isRealParticipant){
				participants[id].resetScore();
			}
		}
	}

	this.updateScores = function(answerId,marks){
		for(var id in participants){
			if(participants[id] && participants[id].isRealParticipant){
				participants[id].updateScore(answerId,marks);
			}
		}

		this.updateRanks();
	}

	this.revertScores = function(answerId,marks){
		for(var id in participants){
			if(participants[id] && participants[id].isRealParticipant){
				participants[id].revertScore(answerId,marks);
			}
		}

		this.updateRanks();
	}

	this.updateRanks = function(){
		leaderboard.updateRanks(participants);
	}

	this.getLeaderboard = function(){
		return leaderboard;
	}

	setInterval(function(participants){
		return function() {
			participants.updateRanks();
		}
	}(this)
	,5000);
}

function Participant(){
	var socket = false;

	this.initParent = function(pSocket){
		socket = pSocket;
		if(socket && socket.handshake && socket.handshake.session){
			if(typeof socket.handshake.session.unique_id === 'undefined'){
				console.log('# Participant connected.');
				socket.handshake.session.unique_id = socket.id;
			}

			socket.handshake.session.ready_for_quiz = true;
			socket.handshake.session.participantId = this.getUniqueId();
			socket.handshake.session.save();
		}
	}

	this.getUniqueId = function(){
		if(socket && socket.handshake && socket.handshake.session && socket.handshake.session.unique_id){
			return socket.handshake.session.unique_id;
		}

		return false;
	}

	this.getQuizId = function(){
		if(socket && socket.handshake && socket.handshake.session && socket.handshake.session.quiz_id){
			return socket.handshake.session.quiz_id;
		}

		return false;
	}

	this.updateSocket = function(pSocket){
		socket = pSocket;
	}

	this.sendUpdates = function(quizState,params){
		if(typeof params!=='undefined' && typeof params.fields!=='undefined'){
			var fields = params.fields;
			for(var f in fields){
				if(fields[f]=='rank'){
					if(this.isRealParticipant){
						quizState.stateParams.rank = this.getRank();
					}
				}
			}
		}

		socket.emit('quiz_state_update',quizState);
	}
}

function Spectator(pSocket){
	this.__proto__ = new Participant();
	this.isSpectator = true;

	this.initParent(pSocket);

	this.getUserType = function(){
		return 'spectator';
	}
}

function RealParticipant(pSocket,pTeamname){
	this.__proto__ = new Participant();
	this.isRealParticipant = true;

	var teamname;
	var response = false;
	var score = 0;
	var rank = 1;
	var lastCorrect = null;

	this.initParentParent = function(pSocket){
		this.initParent(pSocket);
	}

	this.getTeamname = function(){
		return teamname;
	}

	this.setTeamname = function(pTeamname){
		teamname = pTeamname;
	}

	this.setResponse = function(answerId){
		response = answerId;
	}

	this.getResponse = function(){
		return response;
	}

	this.resetResponse = function(){
		response = false;
		this.resetLastCorrect();
	}

	this.updateScore = function(answerId,marks){
		if(answerId == response){
			score += marks;
			this.setLastCorrect(true);
		}
		else{
			this.setLastCorrect(false);
		}
	}

	this.revertScore = function(answerId,marks){
		if(answerId == response){
			score -= marks;
		}
	}

	this.resetScore = function(){
		score = 0;
	}

	this.getScore = function(){
		return score;
	}

	this.getRank = function(){
		return rank;
	}

	this.setRank = function(pRank){
		rank = pRank;
	}

	this.setLastCorrect = function(pLastCorrect){
		lastCorrect = pLastCorrect;
	}

	this.isLastCorrect = function(){
		return lastCorrect;
	}

	this.resetLastCorrect = function(){
		lastCorrect = null;
	}

	this.initParentParent(pSocket);
	this.setTeamname(pTeamname);
}

function OfficialParticipant(pSocket,pTeamname){
	this.__proto__ = new RealParticipant();
	this.isOfficialParticipant = true;

	this.initParentParent(pSocket);
	this.setTeamname(pTeamname);

	this.getUserType = function(){
		return 'official_participant';
	}
}

function UnofficialParticipant(pSocket,pTeamname){
	this.__proto__ = new RealParticipant();
	this.isUnofficialParticipant = true;

	this.initParentParent(pSocket);
	this.setTeamname(pTeamname);

	this.getUserType = function(){
		return 'unofficial_participant';
	}
}

function Administrator(pSocket){
	this.__proto__ = new Participant();
	this.isAdministrator = true;

	this.initParent(pSocket);
	this.getUserType = function(){
		return 'admin';
	}
}

function Questions(){
	var currentQuestion = 0;
	var questions = [];

	this.hasNext = function(){
		if(0<=currentQuestion && currentQuestion<questions.length) return true;
		return false;
	}

	this.next = function(){
		var question = questions[currentQuestion];
		currentQuestion++;
		return question;
	}

	this.addQuestion = function(question){
		questions.push(question);
	}

	this.resetPosition = function(){
		currentQuestion = 0;
	}
}

function Question(){
	var question = "";
	var answers = [];
	var correctAnswerId = 0;
	var pic = "";
	var time = 30;
	var marks = 5;

	this.setQuestion = function(pQuestion){
		question = pQuestion;
	}

	this.setPic = function(pPic){
		pic = pPic;
	}

	this.setMarks = function(pMarks){
		marks = pMarks;
	}

	this.getMarks = function(){
		return marks;
	}

	this.setTime = function(pTime){
		time = pTime;
	}

	this.getTime = function(){
		return time;
	}

	this.addAnswer = function(pAnswer){
		answers.push(pAnswer);
	}

	this.addCorrectAnswer = function(pAnswer){
		answers.push(pAnswer);
		correctAnswerId = answers.length;
	}

	this.getQuestionOnly = function(){
		return {question:question,answers:answers,pic:pic,time:time,marks:marks};
	}

	this.getAnswerId = function(){
		return correctAnswerId;
	}
}

function Leaderboard(){
	var official_participants = [];
	var unofficial_participants = [];
	var updating = false;

	this.get = function(){
		var leaderboard = {};
		leaderboard['official'] = [];
		leaderboard['unofficial'] = [];

		for(var i=0;i<official_participants.length;i++){
			var p = official_participants[i];
			leaderboard['official'].push({team: entities.encode(p.getTeamname()), score: p.getScore(), rank: p.getRank(), isLastCorrect: p.isLastCorrect()});
		}

		for(var i=0;i<unofficial_participants.length;i++){
			var p = unofficial_participants[i];
			leaderboard['unofficial'].push({team: entities.encode(p.getTeamname()), score: p.getScore(), rank: p.getRank(), isLastCorrect: p.isLastCorrect()});
		}

		return leaderboard;
	}

	this.updateRank = function(participant){
		var participantScore = participant.getScore();
		var participantArray = [];

		if(participant.isOfficialParticipant) participantArray = official_participants;
		else if (participant.isUnofficialParticipant) participantArray = unofficial_participants;

		var curRank = 1;

		for(var i=0;i<participantArray.length;i++){
			var curScore = participantArray[i].getScore();
			if(i>0 && curScore != participantArray[i-1].getScore()){
				curRank ++;
			}

			if(participantScore >= curScore ){
				break;
			}
		}

		participant.setRank(curRank);
	}

	this.updateRanks = function(participants){
		if(!updating){
			updating = true;
			var tmp_official_participants = []
			var tmp_unofficial_participants = []

			for(var i in participants){
				var p = participants[i];

				if(p.isOfficialParticipant){
					tmp_official_participants.push(p);
				}
				else if(p.isUnofficialParticipant){
					tmp_unofficial_participants.push(p);
				}
			}

			tmp_official_participants.sort(function(a, b) {
				if(a.getScore()!=b.getScore()) return - a.getScore() + b.getScore();
				else{
					return a.getTeamname().localeCompare(b.getTeamname());
				}
			});

			tmp_unofficial_participants.sort(function(a, b) {
				if(a.getScore()!=b.getScore()) return - a.getScore() + b.getScore();
				else{
					return a.getTeamname().localeCompare(b.getTeamname());
				}
			});

			official_participants = tmp_official_participants;
			unofficial_participants = tmp_unofficial_participants;

			for(p in official_participants){
				var participant = official_participants[p];
				this.updateRank(participant);
			}

			for(p in unofficial_participants){
				var participant = unofficial_participants[p];
				this.updateRank(participant);
			}

			updating = false;
		}
	}
}

function Timer(){
	var timer = false;
	var callback_fn = false;

	this.start = function(seconds,callback){
		callback_fn = callback;

		timer = setTimeout(function(){
			callback_fn();
		}, seconds * 1000);
	}

	this.clear = function(){
		if(timer){
			clearTimeout(globalTimer);
		}

		if(callback_fn){
			callback_fn();
		}
	}
}

function Responses(){
}

function Response(){
}

function QuizState(pQuizId){
	var quizId = pQuizId;
	var curState = states.START;
	var stateParams = false;
	var hiddenParams = false;

	this.get = function(){
		return curState;
	}

	this.setShowTestQuestion = function(pStateParams){
			console.log('# Quiz state changed to TEST_QUESTION ['+quizId+']');
			curState = states.TEST_QUESTION;
			stateParams = pStateParams;
	}

	this.setStart = function(pStateParams){
		console.log('# Quiz state changed to START ['+quizId+']');
		curState = states.START;
		stateParams = pStateParams;
	}

	this.setStarting = function(pStateParams){
		console.log('# Quiz state changed to STARTING ['+quizId+']');
		curState = states.STARTING;
		stateParams = pStateParams;
	}

	this.setShowQuestion = function(pStateParams){
		console.log('# Quiz state changed to SHOW_QUESTION ['+quizId+']');
		curState = states.SHOW_QUESTION;
		stateParams = pStateParams;
	}

	this.setShowAnswer = function(pStateParams){
		console.log('# Quiz state changed to SHOW_ANSWER ['+quizId+']');
		curState = states.SHOW_ANSWER;
		stateParams = pStateParams;
	}

	this.setEnd = function(pStateParams){
		console.log('# Quiz state changed to END ['+quizId+']');
		curState = states.END;
		stateParams = pStateParams;
	}

	this.setHiddenParams = function(pHiddenParams){
		hiddenParams = pHiddenParams;
	}

	this.getHiddenParams = function(){
		return hiddenParams;
	}

	this.getSummary = function(){
		var obj = {};
		obj.state = curState;
		obj.stateParams = stateParams;
		return obj;
	}
}

function Quiz(pQuizId){
	var quizId = pQuizId;
	var timer = new Timer();
	var participants = new Participants();
	var questions = new Questions();
	var quizState = new QuizState(quizId);
	var adminPassword = '';
	var quizCode = '';

	var title = false;
	var pic = false;

	var startWaitTime = 5;

	this.addParticipant = function(participant){
		participants.addParticipant(participant);
	}

	this.getParticipant = function(participantId){
		return participants.getParticipant(participantId);
	}

	this.removeParticipant = function(uniqueId){
		participants.removeParticipant(uniqueId);
	}

	this.nextQuestion = function(){
		var curState = quizState.get();
		if(!(curState==states.STARTING || curState==states.SHOW_ANSWER)) return;

		if(questions.hasNext()){
			var question = questions.next();
			this.showQuestion(question);
		}
		else{
			this.endQuiz();
		}
	}

	this.showTestQuestion = function(){
		var curState = quizState.get();
		if(!(curState==states.START)) return;

		participants.resetResponses();

		var testQuestion = new Question();
		testQuestion.setQuestion('What is the name of the largest continent in the world?');
		testQuestion.addAnswer('Africa');
		testQuestion.addCorrectAnswer('Asia');
		testQuestion.addAnswer('North America');
		testQuestion.addAnswer('South America');
		testQuestion.addAnswer('Antartica');
		testQuestion.addAnswer('Europe');
		testQuestion.setTime(15);

		quizState.setShowTestQuestion(testQuestion.getQuestionOnly());
		quizState.setHiddenParams({answerId: testQuestion.getAnswerId(),test:true, marks: testQuestion.getMarks()});

		this.sendUpdatesToEveryone({});

		timer.start(testQuestion.getTime(),function(quiz){
			return function(){
				quiz.showAnswer();
			}
		}(this));
	}

	this.showQuestion = function(question){
		participants.resetResponses();
		quizState.setShowQuestion(question.getQuestionOnly());
		quizState.setHiddenParams({answerId: question.getAnswerId(),marks: question.getMarks()});

		this.sendUpdatesToEveryone({});

		timer.start(question.getTime(),function(quiz){
			return function(){
				quiz.showAnswer();
			}
		}(this));
	}

	this.collectResponse = function(participant,response){
		var curState = quizState.get();
		if(!(curState==states.SHOW_QUESTION || curState==states.TEST_QUESTION)) return;

		var submittedAnswerId = response.answerId;
		participant.setResponse(submittedAnswerId);
	}

	this.showAnswer = function(){
		var curState = quizState.get();
		if(!(curState==states.SHOW_QUESTION || curState==states.TEST_QUESTION)) return;

		var hiddenParams = quizState.getHiddenParams();
		var answerId = hiddenParams.answerId;
		var test = hiddenParams.test;
		var marks = hiddenParams.marks;

		participants.updateScores(answerId,marks);

		var params = {answerId:answerId};
		if(typeof hiddenParams!='undefined' && typeof hiddenParams.test !=='undefined') params.test = true;
		quizState.setShowAnswer(params);

		this.sendUpdatesToEveryone({fields: ['rank']});

		if(test){
			setTimeout(
			function(gameWorld){
				return function(){
					quizState.setStart(gameWorld.getDetails());
					gameWorld.sendUpdatesToEveryone({});
				}
			}(this),5000);
		}
	}

	this.cancelLastQuestion = function(){
		var curState = quizState.get();
		if(!(curState==states.SHOW_ANSWER)) return;

		var hiddenParams = quizState.getHiddenParams();
		var answerId = hiddenParams.answerId;
		var marks = hiddenParams.marks;

		participants.revertScores(answerId,marks);
		participants.resetResponses();
	}

	this.getLeaderboard = function(){
		return participants.getLeaderboard().get();
	}

	this.startQuiz = function(){
		var curState = quizState.get();
		if(!(curState==states.START)) return;

		participants.resetScores();
		questions.resetPosition();

		quizState.setStarting({seconds: startWaitTime});
		this.sendUpdatesToEveryone({});

		timer.start(startWaitTime,function(quiz){
			return function(){
				quiz.nextQuestion();
			}
		}(this));
	}

	this.endQuiz = function(){
		var curState = quizState.get();
		if(!(curState==states.SHOW_QUESTION || curState==states.SHOW_ANSWER)) return;

		quizState.setEnd();
		this.sendUpdatesToEveryone({});

		setTimeout(
		function(gameWorld){
			return function(){
				quizState.setStart(gameWorld.getDetails());
				gameWorld.sendUpdatesToEveryone({});
			};
		}(this),10000);
	}

	this.isValidTeamname = function(teamname){
		return participants.isValidTeamname(teamname);
	}

	this.sendUpdatesToEveryone = function(params){
		var allParticipants = participants.getAll();
		for(var p in allParticipants){
			this.sendUpdates(allParticipants[p],params);
		}
	}

	this.sendUpdates = function(participant,params){
		var summary = quizState.getSummary();
		participant.sendUpdates(summary,params);
	}

	this.setTitle = function(pTitle){
		this.title = pTitle;
	}

	this.getTitle = function(){
		return this.title;
	}

	this.setPic = function(pPic){
		this.pic = pPic;
	}

	this.getPic = function(){
		return this.pic;
	}

	this.getDetails = function(){
		var details = {};
		details.desc = this.getTitle();
		details.pic = this.getPic();
		return details;
	}

	this.addQuestion = function(question){
		questions.addQuestion(question);
	}

	this.isValidAdminPassword = function(pAdminPassword){
		if(adminPassword == "") return true;
		if(adminPassword == pAdminPassword) return true;
		return false;
	}

	this.isValidQuizCode = function(pQuizCode){
		if(quizCode == '') return true;
		return quizCode == pQuizCode;
	}

	this.setAdminCode = function(pAdminCode){
		if(pAdminCode.length > 20) console.log("# Invalid admin code. Must be less or equal to 20 characters");
		else adminPassword = pAdminCode;
	}

	this.setQuizCode = function(pQuizCode){
		if(pQuizCode.length > 20) console.log("# Invalid quiz code. Must be less or equal to 20 characters");
		else quizCode = pQuizCode;
	}

	this.ready = function(){
		quizState.setStart(this.getDetails());
		this.sendUpdatesToEveryone({});
	}
}