n@656: /**
n@656:  * core.js
n@656:  * 
n@656:  * Main script to run, calls all other core functions and manages loading/store to backend.
n@656:  * Also contains all global variables.
n@656:  */
n@656: 
n@656: 
n@656: /*
n@656:  * 
n@656:  * WARNING!!!
n@656:  * 
n@656:  * 	YOU ARE VIEWING THE DEV VERSION. THERE IS NO GUARANTEE THIS WILL BE FULLY FUNCTIONAL
n@656:  * 
n@656:  * WARNING!!!
n@656:  * 
n@656:  */
n@656: 
n@656: 
n@656: 
n@656: 
n@656: /* create the web audio API context and store in audioContext*/
n@657: var audioContext; // Hold the browser web audio API
n@657: var projectXML; // Hold the parsed setup XML
n@662: 
n@668: var testXMLSetups = []; // Hold the parsed test instances
n@668: var testResultsHolders =[]; // Hold the results from each test for publishing to XML
n@669: var currentTrackOrder = []; // Hold the current XML tracks in their (randomised) order
n@670: var currentTestHolder; // Hold any intermediate results during test - metrics
n@657: var audioEngineContext; // The custome AudioEngine object
n@657: var projectReturn; // Hold the URL for the return
n@657: var preTestQuestions = document.createElement('PreTest'); // Store any pre-test question response
n@657: var postTestQuestions = document.createElement('PostTest'); // Store any post-test question response
n@656: 
n@656: window.onload = function() {
n@656: 	// Function called once the browser has loaded all files.
n@656: 	// This should perform any initial commands such as structure / loading documents
n@656: 	
n@656: 	// Create a web audio API context
n@656: 	// Fixed for cross-browser support
n@656: 	var AudioContext = window.AudioContext || window.webkitAudioContext;
n@656: 	audioContext = new AudioContext;
n@656: 	
n@656: 	// Create the audio engine object
n@656: 	audioEngineContext = new AudioEngine();
n@656: };
n@656: 
n@656: function loadProjectSpec(url) {
n@656: 	// Load the project document from the given URL, decode the XML and instruct audioEngine to get audio data
n@656: 	// If url is null, request client to upload project XML document
n@656: 	var r = new XMLHttpRequest();
n@656: 	r.open('GET',url,true);
n@656: 	r.onload = function() {
n@656: 		loadProjectSpecCallback(r.response);
n@656: 	};
n@656: 	r.send();
n@656: };
n@656: 
n@656: function loadProjectSpecCallback(response) {
n@656: 	// Function called after asynchronous download of XML project specification
n@656: 	var decode = $.parseXML(response);
n@656: 	projectXML = $(decode);
n@656: 	
n@656: 	// Now extract the setup tag
n@656: 	var xmlSetup = projectXML.find('setup');
n@656: 	// Detect the interface to use and load the relevant javascripts.
n@656: 	var interfaceType = xmlSetup[0].attributes['interface'];
n@656: 	var interfaceJS = document.createElement('script');
n@656: 	interfaceJS.setAttribute("type","text/javascript");
n@656: 	if (interfaceType.value == 'APE') {
n@656: 		interfaceJS.setAttribute("src","ape.js");
n@657: 		
n@657: 		// APE comes with a css file
n@657: 		var css = document.createElement('link');
n@657: 		css.rel = 'stylesheet';
n@657: 		css.type = 'text/css';
n@657: 		css.href = 'ape.css';
n@657: 		
n@657: 		document.getElementsByTagName("head")[0].appendChild(css);
n@656: 	}
n@656: 	document.getElementsByTagName("head")[0].appendChild(interfaceJS);
n@656: }
n@656: 
n@656: function createProjectSave(destURL) {
n@656: 	// Save the data from interface into XML and send to destURL
n@656: 	// If destURL is null then download XML in client
n@656: 	// Now time to render file locally
n@656: 	var xmlDoc = interfaceXMLSave();
n@656: 	if (destURL == "null" || destURL == undefined) {
n@656: 		var parent = document.createElement("div");
n@656: 		parent.appendChild(xmlDoc);
n@656: 		var file = [parent.innerHTML];
n@656: 		var bb = new Blob(file,{type : 'application/xml'});
n@656: 		var dnlk = window.URL.createObjectURL(bb);
n@656: 		var a = document.createElement("a");
n@656: 		a.hidden = '';
n@656: 		a.href = dnlk;
n@656: 		a.download = "save.xml";
n@656: 		a.textContent = "Save File";
n@656: 		
n@656: 		var submitDiv = document.getElementById('download-point');
n@656: 		submitDiv.appendChild(a);
n@656: 	}
n@667: 	return submitDiv;
n@656: }
n@656: 
n@656: function AudioEngine() {
n@656: 	
n@656: 	// Create two output paths, the main outputGain and fooGain.
n@656: 	// Output gain is default to 1 and any items for playback route here
n@656: 	// Foo gain is used for analysis to ensure paths get processed, but are not heard
n@656: 	// because web audio will optimise and any route which does not go to the destination gets ignored.
n@656: 	this.outputGain = audioContext.createGain();
n@656: 	this.fooGain = audioContext.createGain();
n@656: 	this.fooGain.gain = 0;
n@656: 	
n@656: 	// Use this to detect playback state: 0 - stopped, 1 - playing
n@656: 	this.status = 0;
n@656: 	
n@656: 	// Connect both gains to output
n@656: 	this.outputGain.connect(audioContext.destination);
n@656: 	this.fooGain.connect(audioContext.destination);
n@656: 	
n@673: 	// Create the timer Object
n@673: 	this.timer = new timer();
n@673: 	// Create session metrics
n@673: 	this.metric = new sessionMetrics(this);
n@673: 	
n@656: 	// Create store for new audioObjects
n@656: 	this.audioObjects = [];
n@656: 	
n@656: 	this.play = function() {
n@656: 		// Send play command to all playback buffers for synchronised start
n@656: 		// Also start timer callbacks to detect if playback has finished
n@656: 		if (this.status == 0) {
n@673: 			this.timer.startTest();
n@656: 			// First get current clock
n@656: 			var timer = audioContext.currentTime;
n@656: 			// Add 3 seconds
n@656: 			timer += 3.0;
n@656: 			
n@656: 			// Send play to all tracks
n@656: 			for (var i=0; i<this.audioObjects.length; i++)
n@656: 			{
n@656: 				this.audioObjects[i].play(timer);
n@656: 			}
n@656: 			this.status = 1;
n@656: 		}
n@656: 	};
n@656: 	
n@656: 	this.stop = function() {
n@656: 		// Send stop and reset command to all playback buffers
n@656: 		if (this.status == 1) {
n@656: 			for (var i=0; i<this.audioObjects.length; i++)
n@656: 			{
n@656: 				this.audioObjects[i].stop();
n@656: 			}
n@656: 			this.status = 0;
n@656: 		}
n@656: 	};
n@656: 	
n@656: 	this.selectedTrack = function(id) {
n@656: 		for (var i=0; i<this.audioObjects.length; i++)
n@656: 		{
n@656: 			if (id == i) {
n@656: 				this.audioObjects[i].outputGain.gain.value = 1.0;
n@656: 			} else {
n@656: 				this.audioObjects[i].outputGain.gain.value = 0.0;
n@656: 			}
n@656: 		}
n@656: 	};
n@656: 	
n@656: 	
n@656: 	this.newTrack = function(url) {
n@656: 		// Pull data from given URL into new audio buffer
n@656: 		// URLs must either be from the same source OR be setup to 'Access-Control-Allow-Origin'
n@656: 		
n@656: 		// Create the audioObject with ID of the new track length;
n@673: 		audioObjectId = this.audioObjects.length;
n@656: 		this.audioObjects[audioObjectId] = new audioObject(audioObjectId);
n@656: 
n@656: 		// AudioObject will get track itself.
n@656: 		this.audioObjects[audioObjectId].constructTrack(url);
n@656: 	};
n@656: 	
n@656: }
n@656: 
n@656: function audioObject(id) {
n@656: 	// The main buffer object with common control nodes to the AudioEngine
n@656: 	
n@656: 	this.id = id;
n@656: 	this.state = 0; // 0 - no data, 1 - ready
n@656: 	this.url = null; // Hold the URL given for the output back to the results.
n@673: 	this.metric = new metricTracker();
n@656: 	
n@656: 	// Create a buffer and external gain control to allow internal patching of effects and volume leveling.
n@656: 	this.bufferNode = audioContext.createBufferSource();
n@656: 	this.outputGain = audioContext.createGain();
n@656: 	
n@656: 	// Default output gain to be zero
n@656: 	this.outputGain.gain.value = 0.0;
n@656: 	
n@656: 	// Connect buffer to the audio graph
n@656: 	this.bufferNode.connect(this.outputGain);
n@656: 	this.outputGain.connect(audioEngineContext.outputGain);
n@656: 	
n@656: 	// the audiobuffer is not designed for multi-start playback
n@656: 	// When stopeed, the buffer node is deleted and recreated with the stored buffer.
n@656: 	this.buffer;
n@656: 	
n@656: 	this.play = function(startTime) {
n@656: 		this.bufferNode.start(startTime);
n@656: 	};
n@656: 	
n@656: 	this.stop = function() {
n@656: 		this.bufferNode.stop(0);
n@656: 		this.bufferNode = audioContext.createBufferSource();
n@656: 		this.bufferNode.connect(this.outputGain);
n@656: 		this.bufferNode.buffer = this.buffer;
n@656: 		this.bufferNode.loop = true;
n@656: 	};
n@656: 
n@656: 	this.constructTrack = function(url) {
n@656: 		var request = new XMLHttpRequest();
n@656: 		this.url = url;
n@656: 		request.open('GET',url,true);
n@656: 		request.responseType = 'arraybuffer';
n@656: 		
n@656: 		var audioObj = this;
n@656: 		
n@656: 		// Create callback to decode the data asynchronously
n@656: 		request.onloadend = function() {
n@656: 			audioContext.decodeAudioData(request.response, function(decodedData) {
n@656: 				audioObj.buffer = decodedData;
n@656: 				audioObj.bufferNode.buffer = audioObj.buffer;
n@656: 				audioObj.bufferNode.loop = true;
n@656: 				audioObj.state = 1;
n@656: 			}, function(){
n@656: 				// Should only be called if there was an error, but sometimes gets called continuously
n@656: 				// Check here if the error is genuine
n@656: 				if (audioObj.state == 0 || audioObj.buffer == undefined) {
n@656: 					// Genuine error
n@656: 					console.log('FATAL - Error loading buffer on '+audioObj.id);
n@656: 				}
n@656: 			});
n@656: 		};
n@656: 		request.send();
n@656: 	};
n@656: 	
n@673: }
n@673: 
n@673: function timer()
n@673: {
n@673: 	/* Timer object used in audioEngine to keep track of session timings
n@673: 	 * Uses the timer of the web audio API, so sample resolution
n@673: 	 */
n@673: 	this.testStarted = false;
n@673: 	this.testStartTime = 0;
n@673: 	this.testDuration = 0;
n@673: 	this.minimumTestTime = 0; // No minimum test time
n@673: 	this.startTest = function()
n@673: 	{
n@673: 		if (this.testStarted == false)
n@673: 		{
n@673: 			this.testStartTime = audioContext.currentTime;
n@673: 			this.testStarted = true;
n@673: 			this.updateTestTime();
n@673: 		}
n@673: 	};
n@673: 	this.stopTest = function()
n@673: 	{
n@673: 		if (this.testStarted)
n@673: 		{
n@673: 			this.testDuration = this.getTestTime();
n@673: 			this.testStarted = false;
n@673: 		} else {
n@673: 			console.log('ERR: Test tried to end before beginning');
n@673: 		}
n@673: 	};
n@673: 	this.updateTestTime = function()
n@673: 	{
n@673: 		if (this.testStarted)
n@673: 		{
n@673: 			this.testDuration = audioContext.currentTime - this.testStartTime;
n@673: 		}
n@673: 	};
n@673: 	this.getTestTime = function()
n@673: 	{
n@673: 		this.updateTestTime();
n@673: 		return this.testDuration;
n@673: 	};
n@673: }
n@673: 
n@673: function sessionMetrics(engine)
n@673: {
n@673: 	/* Used by audioEngine to link to audioObjects to minimise the timer call timers;
n@673: 	 */
n@673: 	this.engine = engine;
n@673: 	this.lastClicked = -1;
n@673: 	this.data = -1;
n@673: 	
n@673: 	this.sliderMoveStart = function(id)
n@673: 	{
n@673: 		if (this.data == -1)
n@673: 		{
n@673: 			this.data = id;
n@673: 		} else {
n@673: 			console.log('ERROR: Metric tracker detecting two moves!');
n@673: 			this.data = -1;
n@673: 		}
n@673: 	};
n@673: 	this.sliderMoved = function()
n@673: 	{
n@673: 		var time = engine.timer.getTestTime();
n@673: 		var id = this.data;
n@673: 		this.data = -1;
n@673: 		var sliderObj = document.getElementsByClassName('track-slider')[id];
n@673: 		var position = Number(sliderObj.style.left.substr(0,sliderObj.style.left.length-2));
n@673: 		if (engine.timer.testStarted)
n@673: 		{
n@673: 			engine.audioObjects[id].metric.moved(time,position);
n@673: 		} else {
n@673: 			engine.audioObjects[id].metric.initialised(position);
n@673: 		}
n@673: 	};
n@673: 	
n@673: 	this.sliderPlayed = function(id)
n@673: 	{
n@673: 		var time = engine.timer.getTestTime();
n@673: 		if (engine.timer.testStarted)
n@673: 		{
n@673: 			if (this.lastClicked >= 0)
n@673: 			{
n@673: 				engine.audioObjects[this.lastClicked].metric.listening(time);
n@673: 			}
n@673: 			this.lastClicked = id;
n@673: 			engine.audioObjects[id].metric.listening(time);
n@673: 		}
n@673: 	};
n@673: }
n@673: 
n@673: function metricTracker()
n@673: {
n@673: 	/* Custom object to track and collect metric data
n@673: 	 * Used only inside the audioObjects object.
n@673: 	 */
n@673: 	
n@673: 	this.listenedTimer = 0;
n@673: 	this.listenStart = 0;
n@673: 	this.initialPosition = 0;
n@673: 	this.movementTracker = [];
n@673: 	this.wasListenedTo = false;
n@673: 	this.wasMoved = false;
n@673: 	this.hasComments = false;
n@673: 	
n@673: 	this.initialised = function(position)
n@673: 	{
n@673: 		this.initialPosition = position;
n@673: 	};
n@673: 	
n@673: 	this.moved = function(time,position)
n@673: 	{
n@673: 		this.wasMoved = true;
n@673: 		this.movementTracker[this.movementTracker.length] = [time, position];
n@673: 	};
n@673: 	
n@673: 	this.listening = function(time)
n@673: 	{
n@673: 		if (this.listenStart == 0)
n@673: 		{
n@673: 			this.wasListenedTo = true;
n@673: 			this.listenStart = time;
n@673: 		} else {
n@673: 			this.listenedTimer += (time - this.listenStart);
n@673: 			this.listenStart = 0;
n@673: 		}
n@673: 	};
n@674: }