waet-hammond-1

/**

 * core.js

 * 

 * Main script to run, calls all other core functions and manages loading/store to backend.

 * Also contains all global variables.

 */

/* create the web audio API context and store in audioContext*/

var audioContext; // Hold the browser web audio API

var projectXML; // Hold the parsed setup XML

var schemaXSD; // Hold the parsed schema XSD

var specification;

var interfaceContext;

var storage;

var popup; // Hold the interfacePopup object

var testState;

var currentTrackOrder = []; // Hold the current XML tracks in their (randomised) order

var audioEngineContext; // The custom AudioEngine object

var projectReturn; 

var returnUrl; // Holds the url to be redirected to at the end of the test

// Add a prototype to the bufferSourceNode to reference to the audioObject holding it

AudioBufferSourceNode.prototype.owner = undefined;

// Add a prototype to the bufferSourceNode to hold when the object was given a play command

AudioBufferSourceNode.prototype.playbackStartTime = undefined;

// Add a prototype to the bufferNode to hold the desired LINEAR gain

AudioBuffer.prototype.playbackGain = undefined;

// Add a prototype to the bufferNode to hold the computed LUFS loudness

AudioBuffer.prototype.lufs = undefined;

// Firefox does not have an XMLDocument.prototype.getElementsByName

// and there is no searchAll style command, this custom function will

// search all children recusrively for the name. Used for XSD where all

// element nodes must have a name and therefore can pull the schema node

XMLDocument.prototype.getAllElementsByName = function(name)

{

    name = String(name);

    var selected = this.documentElement.getAllElementsByName(name);

    return selected;

}

Element.prototype.getAllElementsByName = function(name)

{

    name = String(name);

    var selected = [];

    var node = this.firstElementChild;

    while(node != null)

    {

        if (node.getAttribute('name') == name)

        {

            selected.push(node);

        }

        if (node.childElementCount > 0)

        {

            selected = selected.concat(node.getAllElementsByName(name));

        }

        node = node.nextElementSibling;

    }

    return selected;

}

XMLDocument.prototype.getAllElementsByTagName = function(name)

{

    name = String(name);

    var selected = this.documentElement.getAllElementsByTagName(name);

    return selected;

}

Element.prototype.getAllElementsByTagName = function(name)

{

    name = String(name);

    var selected = [];

    var node = this.firstElementChild;

    while(node != null)

    {

        if (node.nodeName == name)

        {

            selected.push(node);

        }

        if (node.childElementCount > 0)

        {

            selected = selected.concat(node.getAllElementsByTagName(name));

        }

        node = node.nextElementSibling;

    }

    return selected;

}

// Firefox does not have an XMLDocument.prototype.getElementsByName

if (typeof XMLDocument.prototype.getElementsByName != "function") {

    XMLDocument.prototype.getElementsByName = function(name)

    {

        name = String(name);

        var node = this.documentElement.firstElementChild;

        var selected = [];

        while(node != null)

        {

            if (node.getAttribute('name') == name)

            {

                selected.push(node);

            }

            node = node.nextElementSibling;

        }

        return selected;

    }

}

window.onload = function() {

        // Function called once the browser has loaded all files.

        // This should perform any initial commands such as structure / loading documents

        // Create a web audio API context

        // Fixed for cross-browser support

        var AudioContext = window.AudioContext || window.webkitAudioContext;

        audioContext = new AudioContext;

        // Create test state

        testState = new stateMachine();

        // Create the popup interface object

        popup = new interfacePopup();

    // Create the specification object

        specification = new Specification();

        // Create the interface object

        interfaceContext = new Interface(specification);

        // Create the storage object

        storage = new Storage();

        // Define window callbacks for interface

        window.onresize = function(event){interfaceContext.resizeWindow(event);};

};

function loadProjectSpec(url) {

        // Load the project document from the given URL, decode the XML and instruct audioEngine to get audio data

        // If url is null, request client to upload project XML document

        var xmlhttp = new XMLHttpRequest();

        xmlhttp.open("GET",'test-schema.xsd',true);

        xmlhttp.onload = function()

        {

                schemaXSD = xmlhttp.response;

                var parse = new DOMParser();

                specification.schema = parse.parseFromString(xmlhttp.response,'text/xml');

                var r = new XMLHttpRequest();

                r.open('GET',url,true);

                r.onload = function() {

                        loadProjectSpecCallback(r.response);

                };

        r.onerror = function() {

            document.getElementsByTagName('body')[0].innerHTML = null;

            var msg = document.createElement("h3");

            msg.textContent = "FATAL ERROR";

            var span = document.createElement("p");

            span.textContent = "There was an error when loading your XML file. Please check your path in the URL. After the path to this page, there should be '?url=path/to/your/file.xml'. Check the spelling of your filename as well. If you are still having issues, check the log of the python server or your webserver distribution for 404 codes for your file.";

            document.getElementsByTagName('body')[0].appendChild(msg);

            document.getElementsByTagName('body')[0].appendChild(span);

        }

                r.send();

        };

        xmlhttp.send();

};

function loadProjectSpecCallback(response) {

        // Function called after asynchronous download of XML project specification

        //var decode = $.parseXML(response);

        //projectXML = $(decode);

    // Check if XML is new or a resumption

    var parse = new DOMParser();

        var responseDocument = parse.parseFromString(response,'text/xml');

    var errorNode = responseDocument.getElementsByTagName('parsererror');

        if (errorNode.length >= 1)

        {

                var msg = document.createElement("h3");

                msg.textContent = "FATAL ERROR";

                var span = document.createElement("span");

                span.textContent = "The XML parser returned the following errors when decoding your XML file";

                document.getElementsByTagName('body')[0].innerHTML = null;

                document.getElementsByTagName('body')[0].appendChild(msg);

                document.getElementsByTagName('body')[0].appendChild(span);

                document.getElementsByTagName('body')[0].appendChild(errorNode[0]);

                return;

        }

    if (responseDocument.children[0].nodeName == "waet") {

        // document is a specification

        // Perform XML schema validation

        var Module = {

            xml: response,

            schema: schemaXSD,

            arguments:["--noout", "--schema", 'test-schema.xsd','document.xml']

        };

            projectXML = responseDocument;

        var xmllint = validateXML(Module);

        console.log(xmllint);

        if(xmllint != 'document.xml validates\n')

        {

            document.getElementsByTagName('body')[0].innerHTML = null;

            var msg = document.createElement("h3");

            msg.textContent = "FATAL ERROR";

            var span = document.createElement("h4");

            span.textContent = "The XML validator returned the following errors when decoding your XML file";

            document.getElementsByTagName('body')[0].appendChild(msg);

            document.getElementsByTagName('body')[0].appendChild(span);

            xmllint = xmllint.split('\n');

            for (var i in xmllint)

            {

                document.getElementsByTagName('body')[0].appendChild(document.createElement('br'));

                var span = document.createElement("span");

                span.textContent = xmllint[i];

                document.getElementsByTagName('body')[0].appendChild(span);

            }

            return;

        }

        // Build the specification

           specification.decode(projectXML);

        // Generate the session-key

        storage.initialise();

    } else if (responseDocument.children[0].nodeName == "waetresult") {

        // document is a result

        projectXML = document.implementation.createDocument(null,"waet");

        projectXML.children[0].appendChild(responseDocument.getElementsByTagName('waet')[0].getElementsByTagName("setup")[0].cloneNode(true));

        var child = responseDocument.children[0].children[0];

        while (child != null) {

            if (child.nodeName == "survey") {

                // One of the global survey elements

                if (child.getAttribute("state") == "complete") {

                    // We need to remove this survey from <setup>

                    var location = child.getAttribute("location");

                    var globalSurveys = projectXML.getElementsByTagName("setup")[0].getElementsByTagName("survey")[0];

                    while(globalSurveys != null) {

                        if (location == "pre" || location == "before") {

                            if (globalSurveys.getAttribute("location") == "pre" || globalSurveys.getAttribute("location") == "before") {

                                projectXML.getElementsByTagName("setup")[0].removeChild(globalSurveys);

                                break;

                            }

                        } else {

                            if (globalSurveys.getAttribute("location") == "post" || globalSurveys.getAttribute("location") == "after") {

                                projectXML.getElementsByTagName("setup")[0].removeChild(globalSurveys);

                                break;

                            }

                        }

                        globalSurveys = globalSurveys.nextElementSibling;

                    }

                } else {

                    // We need to complete this, so it must be regenerated by store

                    var copy = child;

                    child = child.previousElementSibling;

                    responseDocument.children[0].removeChild(copy);

                }

            } else if (child.nodeName == "page") {

                if (child.getAttribute("state") == "empty") {

                    // We need to complete this page

                    projectXML.children[0].appendChild(responseDocument.getElementById(child.getAttribute("ref")).cloneNode(true));

                    var copy = child;

                    child = child.previousElementSibling;

                    responseDocument.children[0].removeChild(copy);

                }

            }

            child = child.nextElementSibling;

        }

        // Build the specification

            specification.decode(projectXML);

        // Use the original

        storage.initialise(responseDocument);

    }

        /// CHECK FOR SAMPLE RATE COMPATIBILITY

        if (specification.sampleRate != undefined) {

                if (Number(specification.sampleRate) != audioContext.sampleRate) {

                        var errStr = 'Sample rates do not match! Requested '+Number(specification.sampleRate)+', got '+audioContext.sampleRate+'. Please set the sample rate to match before completing this test.';

                        alert(errStr);

                        return;

                }

        }

        // Detect the interface to use and load the relevant javascripts.

        var interfaceJS = document.createElement('script');

        interfaceJS.setAttribute("type","text/javascript");

        switch(specification.interface)

        {

                case "APE":

                interfaceJS.setAttribute("src","interfaces/ape.js");

                // APE comes with a css file

                var css = document.createElement('link');

                css.rel = 'stylesheet';

                css.type = 'text/css';

                css.href = 'interfaces/ape.css';

                document.getElementsByTagName("head")[0].appendChild(css);

                break;

                case "MUSHRA":

                interfaceJS.setAttribute("src","interfaces/mushra.js");

                // MUSHRA comes with a css file

                var css = document.createElement('link');

                css.rel = 'stylesheet';

                css.type = 'text/css';

                css.href = 'interfaces/mushra.css';

                document.getElementsByTagName("head")[0].appendChild(css);

                break;

                case "AB":

                interfaceJS.setAttribute("src","interfaces/AB.js?"+Math.random());

                // AB comes with a css file

                var css = document.createElement('link');

                css.rel = 'stylesheet';

                css.type = 'text/css';

                css.href = 'interfaces/AB.css?'+Math.random();

                document.getElementsByTagName("head")[0].appendChild(css);

                break;

                case "Bipolar":

                case "ACR":

                case "DCR":

                case "CCR":

                case "ABC":

                // Above enumerate to horizontal sliders

                interfaceJS.setAttribute("src","interfaces/horizontal-sliders.js");

                // horizontal-sliders comes with a css file

                var css = document.createElement('link');

                css.rel = 'stylesheet';

                css.type = 'text/css';

                css.href = 'interfaces/horizontal-sliders.css';

                document.getElementsByTagName("head")[0].appendChild(css);

                break;

                case "discrete":

                case "likert":

                // Above enumerate to horizontal discrete radios

                interfaceJS.setAttribute("src","interfaces/discrete.js");

                // horizontal-sliders comes with a css file

                var css = document.createElement('link');

                css.rel = 'stylesheet';

                css.type = 'text/css';

                css.href = 'interfaces/discrete.css';

                document.getElementsByTagName("head")[0].appendChild(css);

                break;

        }

        document.getElementsByTagName("head")[0].appendChild(interfaceJS);

        // Create the audio engine object

        audioEngineContext = new AudioEngine(specification);

}

function createProjectSave(destURL) {

        // Save the data from interface into XML and send to destURL

        // If destURL is null then download XML in client

        // Now time to render file locally

        var xmlDoc = interfaceXMLSave();

        var parent = document.createElement("div");

        parent.appendChild(xmlDoc);

        var file = [parent.innerHTML];

        if (destURL == "local") {

                var bb = new Blob(file,{type : 'application/xml'});

                var dnlk = window.URL.createObjectURL(bb);

                var a = document.createElement("a");

                a.hidden = '';

                a.href = dnlk;

                a.download = "save.xml";

                a.textContent = "Save File";

                popup.showPopup();

                popup.popupContent.innerHTML = "<span>Please save the file below to give to your test supervisor</span><br>";

                popup.popupContent.appendChild(a);

        } else {

                destUrlFull = destURL+"?key="+storage.SessionKey.key;

                var saveFilenamePrefix;

                // parse the querystring of destUrl, get the "id" (if any) and append it to destUrl

                if(typeof(returnUrl) !== "undefined"){

                        var qs = returnUrl.split("?");

                        if(qs.length == 2){

                                qs = qs[1];

                                qs = qs.split("&");

                                for(var n = 0; n < qs.length; n++){

                                        var pair = qs[n].split("=");

                                        if (pair[0] == "id") {

                                                saveFilenamePrefix = pair[1];

                                        }

                                }

                        }

                }

                if(typeof(saveFilenamePrefix) !== "undefined"){

                        destUrlFull+="&saveFilenamePrefix="+saveFilenamePrefix;

                }

                var xmlhttp = new XMLHttpRequest;

                xmlhttp.open("POST",destUrlFull,true);

                xmlhttp.setRequestHeader('Content-Type', 'text/xml');

                xmlhttp.onerror = function(){

                        console.log('Error saving file to server! Presenting download locally');

                        createProjectSave("local");

                };

                xmlhttp.onload = function() {

            console.log(xmlhttp);

            if (this.status >= 300) {

                console.log("WARNING - Could not update at this time");

                createProjectSave("local");

            } else {

                var parser = new DOMParser();

                var xmlDoc = parser.parseFromString(xmlhttp.responseText, "application/xml");

                var response = xmlDoc.getElementsByTagName('response')[0];

                                              window.onbeforeunload=null;

                if (response.getAttribute("state") == "OK") {

                    var file = response.getElementsByTagName("file")[0];

                                                              if(typeof(returnUrl) !== "undefined"){        

                                                                                                window.location = returnUrl;

                                                                                }

                    console.log("Save: OK, written "+file.getAttribute("bytes")+"B");

                    popup.popupContent.textContent = "Thank you. Your session has been saved.";

                      } else {

                    var message = response.getElementsByTagName("message");

                    console.log("Save: Error! "+message.textContent);

                    createProjectSave("local");

                }

            }

        };

                xmlhttp.send(file);

                popup.showPopup();

                popup.popupContent.innerHTML = null;

                popup.popupContent.textContent = "Submitting. Please Wait";

        popup.hideNextButton();

        popup.hidePreviousButton();

        }

}

function errorSessionDump(msg){

        // Create the partial interface XML save

        // Include error node with message on why the dump occured

        popup.showPopup();

        popup.popupContent.innerHTML = null;

        var err = document.createElement('error');

        var parent = document.createElement("div");

        if (typeof msg === "object")

        {

                err.appendChild(msg);

                popup.popupContent.appendChild(msg);

        } else {

                err.textContent = msg;

                popup.popupContent.innerHTML = "ERROR : "+msg;

        }

        var xmlDoc = interfaceXMLSave();

        xmlDoc.appendChild(err);

        parent.appendChild(xmlDoc);

        var file = [parent.innerHTML];

        var bb = new Blob(file,{type : 'application/xml'});

        var dnlk = window.URL.createObjectURL(bb);

        var a = document.createElement("a");

        a.hidden = '';

        a.href = dnlk;

        a.download = "save.xml";

        a.textContent = "Save File";

        popup.popupContent.appendChild(a);

}

// Only other global function which must be defined in the interface class. Determines how to create the XML document.

function interfaceXMLSave(){

        // Create the XML string to be exported with results

        return storage.finish();

}

function linearToDecibel(gain)

{

        return 20.0*Math.log10(gain);

}

function decibelToLinear(gain)

{

        return Math.pow(10,gain/20.0);

}

function randomString(length) {

    return Math.round((Math.pow(36, length + 1) - Math.random() * Math.pow(36, length))).toString(36).slice(1);

}

function interfacePopup() {

        // Creates an object to manage the popup

        this.popup = null;

        this.popupContent = null;

        this.popupTitle = null;

        this.popupResponse = null;

        this.buttonProceed = null;

        this.buttonPrevious = null;

        this.popupOptions = null;

        this.currentIndex = null;

        this.node = null;

        this.store = null;

        $(window).keypress(function(e){

                        if (e.keyCode == 13 && popup.popup.style.visibility == 'visible')

                        {

                                console.log(e);

                                popup.buttonProceed.onclick();

                                e.preventDefault();

                        }

                });

        this.createPopup = function(){

                // Create popup window interface

                var insertPoint = document.getElementById("topLevelBody");

                this.popup = document.getElementById('popupHolder');

                this.popup.style.left = (window.innerWidth/2)-250 + 'px';

                this.popup.style.top = (window.innerHeight/2)-125 + 'px';

                this.popupContent = document.getElementById('popupContent');

                this.popupTitle = document.getElementById('popupTitle');

                this.popupResponse = document.getElementById('popupResponse');

                this.buttonProceed = document.getElementById('popup-proceed');

                this.buttonProceed.onclick = function(){popup.proceedClicked();};

                this.buttonPrevious = document.getElementById('popup-previous');

                this.buttonPrevious.onclick = function(){popup.previousClick();};

        this.hidePopup();

                this.popup.style.zIndex = -1;

                this.popup.style.visibility = 'hidden';

        };

        this.showPopup = function(){

                if (this.popup == null) {

                        this.createPopup();

                }

                this.popup.style.zIndex = 3;

                this.popup.style.visibility = 'visible';

                var blank = document.getElementsByClassName('testHalt')[0];

                blank.style.zIndex = 2;

                blank.style.visibility = 'visible';

        };

        this.hidePopup = function(){

                this.popup.style.zIndex = -1;

                this.popup.style.visibility = 'hidden';

                var blank = document.getElementsByClassName('testHalt')[0];

                blank.style.zIndex = -2;

                blank.style.visibility = 'hidden';

                this.buttonPrevious.style.visibility = 'inherit';

        };

        this.postNode = function() {

                // This will take the node from the popupOptions and display it

                var node = this.popupOptions[this.currentIndex];

                this.popupResponse.innerHTML = null;

                this.popupTitle.textContent = node.specification.statement;

                if (node.specification.type == 'question') {

                        var textArea = document.createElement('textarea');

                        switch (node.specification.boxsize) {

                        case 'small':

                                textArea.cols = "20";

                                textArea.rows = "1";

                                break;

                        case 'normal':

                                textArea.cols = "30";

                                textArea.rows = "2";

                                break;

                        case 'large':

                                textArea.cols = "40";

                                textArea.rows = "5";

                                break;

                        case 'huge':

                                textArea.cols = "50";

                                textArea.rows = "10";

                                break;

                        }

            if (node.response == undefined) {

                node.response = "";

            } else {

                textArea.value = node.response;

            }

                        this.popupResponse.appendChild(textArea);

                        textArea.focus();

            this.popupResponse.style.textAlign="center";

            this.popupResponse.style.left="0%";

                } else if (node.specification.type == 'checkbox') {

            if (node.response == undefined) {

                node.response = Array(node.specification.options.length);

            }

            var index = 0;

            var max_w = 0;

                        for (var option of node.specification.options) {

                                var input = document.createElement('input');

                                input.id = option.name;

                                input.type = 'checkbox';

                                var span = document.createElement('span');

                                span.textContent = option.text;

                                var hold = document.createElement('div');

                                hold.setAttribute('name','option');

                                hold.style.padding = '4px';

                                hold.appendChild(input);

                                hold.appendChild(span);

                                this.popupResponse.appendChild(hold);

                if (node.response[index] != undefined){

                    if (node.response[index].checked == true) {

                        input.checked = "true";

                    }

                }

                var w = $(span).width();

                if (w > max_w)

                    max_w = w;

                index++;

                        }

            max_w += 12;

            this.popupResponse.style.textAlign="";

            var leftP = ((max_w/500)/2)*100;

            this.popupResponse.style.left=leftP+"%";

                } else if (node.specification.type == 'radio') {

            if (node.response == undefined) {

                node.response = {name: "", text: ""};

            }

            var index = 0;

            var max_w = 0;

                        for (var option of node.specification.options) {

                                var input = document.createElement('input');

                                input.id = option.name;

                                input.type = 'radio';

                                input.name = node.specification.id;

                                var span = document.createElement('span');

                                span.textContent = option.text;

                                var hold = document.createElement('div');

                                hold.setAttribute('name','option');

                                hold.style.padding = '4px';

                                hold.appendChild(input);

                                hold.appendChild(span);

                                this.popupResponse.appendChild(hold);

                if (input.id == node.response.name) {

                    input.checked = "true";

                }

                var w = $(span).width();

                if (w > max_w)

                    max_w = w;

                        }

            max_w += 12;

            this.popupResponse.style.textAlign="";

            var leftP = ((max_w/500)/2)*100;

            this.popupResponse.style.left=leftP+"%";

                } else if (node.specification.type == 'number') {

                        var input = document.createElement('input');

                        input.type = 'textarea';

                        if (node.min != null) {input.min = node.specification.min;}

                        if (node.max != null) {input.max = node.specification.max;}

                        if (node.step != null) {input.step = node.specification.step;}

            if (node.response != undefined) {

                input.value = node.response;

            }

                        this.popupResponse.appendChild(input);

            this.popupResponse.style.textAlign="center";

            this.popupResponse.style.left="0%";

                }

                if(this.currentIndex+1 == this.popupOptions.length) {

                        if (this.node.location == "pre") {

                                this.buttonProceed.textContent = 'Start';

                        } else {

                                this.buttonProceed.textContent = 'Submit';

                        }

                } else {

                        this.buttonProceed.textContent = 'Next';

                }

                if(this.currentIndex > 0)

                        this.buttonPrevious.style.visibility = 'visible';

                else

                        this.buttonPrevious.style.visibility = 'hidden';

        };

        this.initState = function(node,store) {

                //Call this with your preTest and postTest nodes when needed to

                // initialise the popup procedure.

                if (node.options.length > 0) {

                        this.popupOptions = [];

                        this.node = node;

                        this.store = store;

                        for (var opt of node.options)

                        {

                                this.popupOptions.push({

                                        specification: opt,

                                        response: null

                                });

                        }                        

                        this.currentIndex = 0;

                        this.showPopup();

                        this.postNode();

                } else {

                        advanceState();

                }

        };

        this.proceedClicked = function() {

                // Each time the popup button is clicked!

                var node = this.popupOptions[this.currentIndex];

                if (node.specification.type == 'question') {

                        // Must extract the question data

                        var textArea = $(popup.popupContent).find('textarea')[0];

                        if (node.specification.mandatory == true && textArea.value.length == 0) {

                                alert('This question is mandatory');

                                return;

                        } else {

                                // Save the text content

                                console.log("Question: "+ node.specification.statement);

                                console.log("Question Response: "+ textArea.value);

                                node.response = textArea.value;

                        }

                } else if (node.specification.type == 'checkbox') {

                        // Must extract checkbox data

                        console.log("Checkbox: "+ node.specification.statement);

                        var inputs = this.popupResponse.getElementsByTagName('input');

                        node.response = [];

                        for (var i=0; i<node.specification.options.length; i++) {

                                node.response.push({

                                        name: node.specification.options[i].name,

                                        text: node.specification.options[i].text,

                                        checked: inputs[i].checked

                                });

                                console.log(node.specification.options[i].name+": "+ inputs[i].checked);

                        }

                } else if (node.specification.type == "radio") {

                        var optHold = this.popupResponse;

                        console.log("Radio: "+ node.specification.statement);

                        node.response = null;

                        var i=0;

                        var inputs = optHold.getElementsByTagName('input');

                        while(node.response == null) {

                                if (i == inputs.length)

                                {

                                        if (node.specification.mandatory == true)

                                        {

                                                alert("This radio is mandatory");

                                        } else {

                                                node.response = -1;

                                        }

                                        return;

                                }

                                if (inputs[i].checked == true) {

                                        node.response = node.specification.options[i];

                                        console.log("Selected: "+ node.specification.options[i].name);

                                }

                                i++;

                        }

                } else if (node.specification.type == "number") {

                        var input = this.popupContent.getElementsByTagName('input')[0];

                        if (node.mandatory == true && input.value.length == 0) {

                                alert('This question is mandatory. Please enter a number');

                                return;

                        }

                        var enteredNumber = Number(input.value);

                        if (isNaN(enteredNumber)) {

                                alert('Please enter a valid number');

                                return;

                        }

                        if (enteredNumber < node.min && node.min != null) {

                                alert('Number is below the minimum value of '+node.min);

                                return;

                        }

                        if (enteredNumber > node.max && node.max != null) {

                                alert('Number is above the maximum value of '+node.max);

                                return;

                        }

                        node.response = input.value;

                }

                this.currentIndex++;

                if (this.currentIndex < this.popupOptions.length) {

                        this.postNode();

                } else {

                        // Reached the end of the popupOptions

                        this.hidePopup();

                        for (var node of this.popupOptions)

                        {

                                this.store.postResult(node);

                        }

            this.store.complete();

                        advanceState();

                }

        };

        this.previousClick = function() {

                // Triggered when the 'Back' button is clicked in the survey

                if (this.currentIndex > 0) {

                        this.currentIndex--;

                        this.postNode();

                }

        };

        this.resize = function(event)

        {

                // Called on window resize;

                if (this.popup != null) {

                        this.popup.style.left = (window.innerWidth/2)-250 + 'px';

                        this.popup.style.top = (window.innerHeight/2)-125 + 'px';

                        var blank = document.getElementsByClassName('testHalt')[0];

                        blank.style.width = window.innerWidth;

                        blank.style.height = window.innerHeight;

                }

        };

    this.hideNextButton = function() {

        this.buttonProceed.style.visibility = "hidden";

    }

    this.hidePreviousButton = function() {

        this.buttonPrevious.style.visibility = "hidden";

    }

    this.showNextButton = function() {

        this.buttonProceed.style.visibility = "visible";

    }

    this.showPreviousButton = function() {

        this.buttonPrevious.style.visibility = "visible";

    }

}

function advanceState()

{

        // Just for complete clarity

        testState.advanceState();

}

function stateMachine()

{

        // Object prototype for tracking and managing the test state

        this.stateMap = [];

        this.preTestSurvey = null;

        this.postTestSurvey = null;

        this.stateIndex = null;

        this.currentStateMap = null;

        this.currentStatePosition = null;

    this.currentStore = null;

        this.initialise = function(){

                // Get the data from Specification

                var pageHolder = [];

                for (var page of specification.pages)

                {

            var repeat = page.repeatCount;

            while(repeat >= 0)

            {

                pageHolder.push(page);

                repeat--;

            }

                }

                if (specification.randomiseOrder)

                {

                        pageHolder = randomiseOrder(pageHolder);

                }

                for (var i=0; i<pageHolder.length; i++)

                {

                        pageHolder[i].presentedId = i;

                }

                for (var i=0; i<specification.pages.length; i++)

                {

                        if (specification.testPages <= i && specification.testPages != 0) {break;}

                        this.stateMap.push(pageHolder[i]);

            storage.createTestPageStore(pageHolder[i]);

            for (var element of pageHolder[i].audioElements) {

                var URL = pageHolder[i].hostURL + element.url;

                var buffer = null;

                for (var buffObj of audioEngineContext.buffers) {

                    if (URL == buffObj.url) {

                        buffer = buffObj;

                        break;

                    }

                }

                if (buffer == null) {

                    buffer = new audioEngineContext.bufferObj();

                    buffer.getMedia(URL);

                    audioEngineContext.buffers.push(buffer);

                }

            }

                }

                if (specification.preTest != null) {this.preTestSurvey = specification.preTest;}

                if (specification.postTest != null) {this.postTestSurvey = specification.postTest;}

                if (this.stateMap.length > 0) {

                        if(this.stateIndex != null) {

                                console.log('NOTE - State already initialise');

                        }

                        this.stateIndex = -1;

                } else {

                        console.log('FATAL - StateMap not correctly constructed. EMPTY_STATE_MAP');

                }

        };

        this.advanceState = function(){

                if (this.stateIndex == null) {

                        this.initialise();

                }

                 $('#box-holders').fadeTo(200, 0.1, function(){

                         $('#box-holders').fadeTo(200, 1);

                });

                storage.update();

                if (this.stateIndex == -1) {

                        this.stateIndex++;

                        console.log('Starting test...');

                        if (this.preTestSurvey != null)

                        {

                                popup.initState(this.preTestSurvey,storage.globalPreTest);

                        } else {

                                this.advanceState();

                        }

                } else if (this.stateIndex == this.stateMap.length)

                {

                        // All test pages complete, post test

                        console.log('Ending test ...');

                        this.stateIndex++;

                        if (this.postTestSurvey == null) {

                                this.advanceState();

                        } else {

                                popup.initState(this.postTestSurvey,storage.globalPostTest);

                        }

                } else if (this.stateIndex > this.stateMap.length)

                {

                        createProjectSave(specification.projectReturn);

                }

                else

                {

                        if (this.currentStateMap == null)

                        {

                                this.currentStateMap = this.stateMap[this.stateIndex];

                                if (this.currentStateMap.randomiseOrder)

                                {

                                        this.currentStateMap.audioElements = randomiseOrder(this.currentStateMap.audioElements);

                                }

                this.currentStore = storage.testPages[this.stateIndex];

                                if (this.currentStateMap.preTest != null)

                                {

                                        this.currentStatePosition = 'pre';

                                        popup.initState(this.currentStateMap.preTest,storage.testPages[this.stateIndex].preTest);

                                } else {

                                        this.currentStatePosition = 'test';

                                }

                                interfaceContext.newPage(this.currentStateMap,storage.testPages[this.stateIndex]);

                                return;

                        }

                        switch(this.currentStatePosition)

                        {

                        case 'pre':

                                this.currentStatePosition = 'test';

                                break;

                        case 'test':

                                this.currentStatePosition = 'post';

                                // Save the data

                                this.testPageCompleted();

                                if (this.currentStateMap.postTest == null)

                                {

                                        this.advanceState();

                                        return;

                                } else {

                                        popup.initState(this.currentStateMap.postTest,storage.testPages[this.stateIndex].postTest);

                                }

                                break;

                        case 'post':

                                this.stateIndex++;

                                this.currentStateMap = null;

                                this.advanceState();

                                break;

                        };

                }

        };

        this.testPageCompleted = function() {

                // Function called each time a test page has been completed

                var storePoint = storage.testPages[this.stateIndex];

                // First get the test metric

                var metric = storePoint.XMLDOM.getElementsByTagName('metric')[0];

                if (audioEngineContext.metric.enableTestTimer)

                {

                        var testTime = storePoint.parent.document.createElement('metricresult');

                        testTime.id = 'testTime';

                        testTime.textContent = audioEngineContext.timer.testDuration;

                        metric.appendChild(testTime);

                }

                var audioObjects = audioEngineContext.audioObjects;

                for (var ao of audioEngineContext.audioObjects) 

                {

                        ao.exportXMLDOM();

                }

                for (var element of interfaceContext.commentQuestions)

                {

                        element.exportXMLDOM(storePoint);

                }

                pageXMLSave(storePoint.XMLDOM, this.currentStateMap);

        storePoint.complete();

        };

}

function AudioEngine(specification) {

        // Create two output paths, the main outputGain and fooGain.

        // Output gain is default to 1 and any items for playback route here

        // Foo gain is used for analysis to ensure paths get processed, but are not heard

        // because web audio will optimise and any route which does not go to the destination gets ignored.

        this.outputGain = audioContext.createGain();

        this.fooGain = audioContext.createGain();

        this.fooGain.gain = 0;

        // Use this to detect playback state: 0 - stopped, 1 - playing

        this.status = 0;

        // Connect both gains to output

        this.outputGain.connect(audioContext.destination);

        this.fooGain.connect(audioContext.destination);

        // Create the timer Object

        this.timer = new timer();

        // Create session metrics

        this.metric = new sessionMetrics(this,specification);

        this.loopPlayback = false;

        this.pageStore = null;

        // Create store for new audioObjects

        this.audioObjects = [];

        this.buffers = [];

        this.bufferObj = function()

        {

                this.url = null;

                this.buffer = null;

                this.xmlRequest = new XMLHttpRequest();

                this.xmlRequest.parent = this;

                this.users = [];

        this.progress = 0;

        this.status = 0;

                this.ready = function()

                {

            if (this.status >= 2)

            {

                this.status = 3;

            }

                        for (var i=0; i<this.users.length; i++)

                        {

                                this.users[i].state = 1;

                                if (this.users[i].interfaceDOM != null)

                                {

                                        this.users[i].bufferLoaded(this);

                                }

                        }

                };

                this.getMedia = function(url) {

                        this.url = url;

                        this.xmlRequest.open('GET',this.url,true);

                        this.xmlRequest.responseType = 'arraybuffer';

                        var bufferObj = this;

                        // Create callback to decode the data asynchronously

                        this.xmlRequest.onloadend = function() {

                // Use inbuilt WAVE decoder first

                if (this.status == -1) {return;}

                var waveObj = new WAVE();

                if (waveObj.open(bufferObj.xmlRequest.response) == 0)

                {

                    bufferObj.buffer = audioContext.createBuffer(waveObj.num_channels,waveObj.num_samples,waveObj.sample_rate);

                    for (var c=0; c<waveObj.num_channels; c++)

                    {

                        var buffer_ptr = bufferObj.buffer.getChannelData(c);

                        for (var n=0; n<waveObj.num_samples; n++)

                        {

                            buffer_ptr[n] = waveObj.decoded_data[c][n];

                        }

                    }

                    delete waveObj;

                } else {

                    audioContext.decodeAudioData(bufferObj.xmlRequest.response, function(decodedData) {

                        bufferObj.buffer = decodedData;

                    }, function(e){

                        // Should only be called if there was an error, but sometimes gets called continuously

                        // Check here if the error is genuine

                        if (bufferObj.xmlRequest.response == undefined) {

                            // Genuine error

                            console.log('FATAL - Error loading buffer on '+audioObj.id);

                            if (request.status == 404)

                            {

                                console.log('FATAL - Fragment '+audioObj.id+' 404 error');

                                console.log('URL: '+audioObj.url);

                                errorSessionDump('Fragment '+audioObj.id+' 404 error');

                            }

                            this.parent.status = -1;

                        }

                    });

                }

                if (bufferObj.buffer != undefined)

                {

                    bufferObj.status = 2;

                    calculateLoudness(bufferObj,"I");

                }

                        };

            // Create callback for any error in loading

            this.xmlRequest.onerror = function() {

                this.parent.status = -1;

                for (var i=0; i<this.parent.users.length; i++)

                {

                    this.parent.users[i].state = -1;

                    if (this.parent.users[i].interfaceDOM != null)

                    {

                        this.parent.users[i].bufferLoaded(this);

                    }

                }

            }

                        this.progress = 0;

                        this.progressCallback = function(event){

                                if (event.lengthComputable)

                                {

                                        this.parent.progress = event.loaded / event.total;

                                        for (var i=0; i<this.parent.users.length; i++)

                                        {

                                                if(this.parent.users[i].interfaceDOM != null)

                                                {

                                                        if (typeof this.parent.users[i].interfaceDOM.updateLoading === "function")

                                                        {

                                                                this.parent.users[i].interfaceDOM.updateLoading(this.parent.progress*100);

                                                        }

                                                }

                                        }

                                }

                        };

                        this.xmlRequest.addEventListener("progress", this.progressCallback);

            this.status = 1;

                        this.xmlRequest.send();

                };

        this.registerAudioObject = function(audioObject)

        {

            // Called by an audioObject to register to the buffer for use

            // First check if already in the register pool

            for (var objects of this.users)

            {

                if (audioObject.id == objects.id){return 0;}

            }

            this.users.push(audioObject);

            if (this.status == 3 || this.status == -1)