var AUDIOBUFFSIZE = 1024;

const SaveTypes = {
	Savestate: "savestate",
	Disk: "disk",
	ISO: "iso",
	BaseImage: "baseimage",
}

class MyClass {
    constructor() {
        this.rom_name = '';
        this.rom_size = 0;
        this.mobileMode = false;
        this.iosMode = false;
        this.base_name = '';
        this.initCount = 0;
        this.baseImageSaved = false;
        this.isoSaved = false;
        this.moduleInitializing = true;
        this.exportFilesRequested = false;
        this.lblError = '';
        this.isoMounted = false;
        this.floppyMounted = false;
        this.canvasHeight = 480;
        this.ram = 32;
        this.initialHardDrive = 'hd_520';
        this.dosVersion = '7.1';
        this.iso_loaded = false;
        this.noIso = false;
        this.importedFileNames = [];
        this.isSpecialHandler = false;
        this.img_loaded = false;
        this.cueFile = '';
        this.hasBinCue = false;
        this.beforeEmulatorStarted = true;
        this.audioInited = false;
        this.dblistSavestates = [];
        this.dblistDisks = [];
        this.dblistBaseImages = [];
        this.dblistIsos = [];
        this.multiFiles = [];
        this.multiFileMode = false;
        this.singleFileUpload = false;
        this.noLocalSave = true;
        this.message = '';
        this.loading = true;
        this.isoName = '';
        this.loginModalOpened = false;
        this.noCloudSave = true;
        this.password = '';
        this.loggedIn = false;
        this.dosSaveStates = [];
        this.allSaveStates = [];
        this.baseHardDrive = new Uint8Array();
        this.compareCount = 0;
        this.doIntegrityCheck = false;
        this.cpu = 'auto';
        this.showLoadAndSavestate = false;
        this.loadSavestateAfterBoot = false;
        this.noCopyImport = false;
        this.changeCD = false;
        this.changeFloppy = false;
        this.loadFloppy = false;
        this.isDosMode = true;
        this.autoKeyboard = false;
        this.autoKeyboardTimer = 0;
        this.autoKeyboardInterval = 48*180; //three minutes (audioprocessrecurring gets called 48 times a second)
        this.lastCalledTime = new Date();
        this.fpscounter = 0;
        this.currentfps = 0;
        this.fpsInterval = 1000 / 60;
        this.then = Date.now();
        this.hasCloud = false;
        this.initialInstallation = false;
        this.hardDiskFallbackFromFloppy = false;
        this.ranWindowsSetup = false;
        this.win95InstallationFix = false;
        this.winNotFoundCommands = '';
        this.doswasmxBatFound = false;
        this.romList = [];
        this.settings = {
            CLOUDSAVEURL: "",
            ISOURL: "",
            DEFAULTIMG: ""
        };
        this.specialFileHandlers = 
        [
            '.7z',
            '.zip',
            '.bin',
            '.cue',
            '.img',
            '.iso'
        ];
        var Module = {};
        Module['canvas'] = document.getElementById('canvas');
        window['Module'] = Module;
        document.getElementById('file-upload').addEventListener('change', this.uploadRom.bind(this));
        document.getElementById('file-import').addEventListener('change', this.importFiles.bind(this));

        //comes from settings.js
        this.settings = window["DOSWASMSETTINGS"];

        if (this.settings.CLOUDSAVEURL)
        {
            this.hasCloud = true;
        }

        if (window["ROMLIST"].length > 0)
        {
            window["ROMLIST"].forEach(rom => {
                this.romList.push(rom);
            });
        }
        

        rivets.formatters.ev = function (value, arg) {
            return eval(value + arg);
        }
        rivets.formatters.ev_string = function (value, arg) {
            let eval_string = "'" + value + "'" + arg;
            return eval(eval_string);
        }

        rivets.bind(document.getElementById('maindiv'), { data: this });
        rivets.bind(document.getElementById('importModal'), { data: this });
        rivets.bind(document.getElementById('loginModal'), { data: this });
        rivets.bind(document.getElementById('settingsModal'), { data: this });
        rivets.bind(document.getElementById('divInstructions'), { data: this });
        
        this.detectBrowser();
        this.setupDragDropRom();
        this.createDB();
        this.retrieveSettings();

        if (this.hasCloud)
        {
            this.setupLogin();
        }


        $('#topPanel').show();
        $('#errorOuter').show();
        
    }

    detectBrowser(){
        if (navigator.userAgent.toLocaleLowerCase().includes('iphone'))
        {
            this.iosMode = true;
            try {
                let iosVersion = navigator.userAgent.substring(navigator.userAgent.indexOf("iPhone OS ") + 10);
                iosVersion = iosVersion.substring(0, iosVersion.indexOf(' '));
                iosVersion = iosVersion.substring(0, iosVersion.indexOf('_'));
                this.iosVersion = parseInt(iosVersion);
            } catch (err) { }
        }
        if (window.innerWidth < 600 || this.iosMode)
            this.mobileMode = true;
        else
            this.mobileMode = false;

        // firefox only supports 250 megs??
        if (navigator.userAgent.toLocaleLowerCase().includes('firefox'))
        {
            this.initialHardDrive = 'hd_250';
        }

        if (this.iosMode)
        {
            this.initialHardDrive = 'hd -size 25';
        }

        if (this.mobileMode)
        {
            this.canvasHeight = window.innerWidth / 2;
            console.log('detected mobile mode - canvasheight: ' + this.canvasHeight)
        }
    }

    //DRAG AND DROP ROM
    setupDragDropRom(){
        let dropArea = document.getElementById('dropArea');

        dropArea.addEventListener('dragenter', this.preventDefaults, false);
        dropArea.addEventListener('dragover', this.preventDefaults, false);
        dropArea.addEventListener('dragleave', this.preventDefaults, false);
        dropArea.addEventListener('drop', this.preventDefaults, false);
        
        dropArea.addEventListener('dragenter', this.dragDropHighlight, false);
        dropArea.addEventListener('dragover', this.dragDropHighlight, false);
        dropArea.addEventListener('dragleave', this.dragDropUnHighlight, false);
        dropArea.addEventListener('drop', this.dragDropUnHighlight, false);

        dropArea.addEventListener('drop', this.handleDrop, false);

    }

    preventDefaults(e){
        e.preventDefault();
        e.stopPropagation();
    }

    dragDropHighlight(e){
        $('#dropArea').css({"background-color": "lightblue"});
    }

    dragDropUnHighlight(e){
        $('#dropArea').css({"background-color": "inherit"});
    }

    handleDrop(e){
        myClass.initAudio();
        myClass.showProgress = true;

        let dt = e.dataTransfer;
        let files = dt.files;
        
        if (files.length == 1)
        {
            myClass.detectSingleFileUpload(files[0].name);
        }
        else if (files.length > 1)
        {
            myClass.handleMultipleFiles(files, 0);
            return;
        }

        var file = files[0];
        myClass.rom_name = file.name;
        myClass.extractBaseName();

        console.log(file);
        var reader = new FileReader();
        reader.onprogress = function (event) {
            myClass.handleProgress(event, file);
        };
        reader.onload = function (e) {
            console.log('finished loading');
            var byteArray = new Uint8Array(this.result);
            myClass.LoadEmulator(byteArray);
        }
        reader.readAsArrayBuffer(file);

    }

    handleProgress(event, file){
        console.log('loaded: ' + event.loaded);
        let loaded = event.loaded;
        let total = event.total;
        let percent = (loaded / total)*100;

        loaded = Math.ceil(loaded / 1000000);
        total = Math.ceil(total / 1000000);

        let formatted = file.name + ' ' + loaded + 'MB / ' + total + 'MB';
        
        document.getElementById('myProgress').style.width= percent + '%';
        document.getElementById('myProgress').innerHTML = formatted;
    }
    

    configureEmulator(){

        if (this.password)
            this.loginSilent();

        let size = localStorage.getItem('doswasmx-height');
        if (size) {
            console.log('size found');
            let sizeNum = parseInt(size);
            this.canvasHeight = sizeNum;
        }

        this.resizeCanvas();

        $('#canvasDiv').show();
        $('#divInstructions').show();

    }

    processPrintStatement(text) {
        console.log(text);

        //they tried to load an .img file that turned out to be a floppy disk
        if (text.includes('detected floppy disk'))
        {
            if (this.dblistDisks.length == 0 && !this.settings.DEFAULTIMG)
            {
                //this means they don't have a hard disk
                myClass.base_name = 'mydisk';
                myClass.initialInstallation = true;
            }
            else
            {
                //fall back to using their hard drive
                myClass.base_name = 'mydisk';
                myClass.hardDiskFallbackFromFloppy = true;
            }
        }

        //we detected a floppy disk
        if (text.includes('floppy disk mounted'))
        {
            setTimeout(() => {
                if (myClass.initialInstallation)
                {
                    myClass.sendDosCommands(
                        'imgmake \"' + this.base_name + ".img\" -t " + this.initialHardDrive + "\n" +
                        'imgmount c \"' + this.base_name + ".img\na:\n");
                }
                else if (myClass.hardDiskFallbackFromFloppy)
                {
                    //if they already have a hard disk we load it
                    //currently does not support this.settings.DEFAULTIMG + dragging .img floppy
                    if (this.dblistDisks.length > 0)
                    {
                        this.loadFromDatabase(SaveTypes.Disk);
                    }
                }
                else
                {
                    myClass.sendDosCommands("a:\n");
                }
                myClass.floppyMounted = true;
            }, 
            
            //TODO this is a hack
            //dos commands should queue up rather
            //than overwrite eachother
            500);
        }



        //this means we detected the windows cd
        if (text.includes("iso mounted root file: WIN98") || text.includes("iso mounted root file: WIN95"))
        {
            //auto start the setup process - only do this once
            if (!myClass.ranWindowsSetup)
            {
                myClass.ranWindowsSetup = true;
                setTimeout(() => {
                    myClass.initialInstallation = true;
                    myClass.sendDosCommands("d:setup.exe\n");
                }, 50);

                //set cpu to max during windows installation
                setTimeout(() => {
                    myClass.updateCpuNeil('cycles=max');
                }, 100);
            }
        }

        if (text.includes('windows not found') || text.includes('found noboot.txt'))
        {
            //if we don't detect a windows installation just send
            //them to the C drive
            setTimeout(() => {

                let dosCommands = "c:\n";

                //if we found a DOSWASMX.BAT we run it
                if (myClass.doswasmxBatFound)
                {
                    dosCommands += 'doswasmx.bat\n'
                }

                //add any additional commands appended based on the rom file
                dosCommands += myClass.winNotFoundCommands;

                //send it to the dos shell
                myClass.sendDosCommands(dosCommands);

                //clear it for next time
                myClass.winNotFoundCommands = '';
            }, 50);
        }

        if (text.includes('Parsing command line: d:setup.exe'))
        {
            //a bunch of hacks to get it to dismiss the install
            //warnings for win95rtm, win95osr2, and win98se
            if (myClass.initialInstallation)
            {
                setTimeout(() => {
                    myClass.sendKey(52); //enter
                }, 1000); 
                setTimeout(() => {
                    myClass.sendKey(49); //escape
                }, 3000);
                setTimeout(() => {
                    myClass.sendKey(52); //enter
                }, 3100);
            }
        }

        if (text.includes('Plug & Play OS reports itself inactive'))
        {
            //this is hack during windows 95 installation 
            //where it doesnt detect one of the restarts
            if (myClass.initialInstallation && !myClass.win95InstallationFix)
            {
                console.log('windows95 fix');
                myClass.win95InstallationFix = true;
                setTimeout(() => {
                    myClass.updateAutoexecAdditional("boot c:\r\n");
                    // myClass.saveDrive();    
                }, 100);
            }
        }

        if (text.includes('drive mounted C file: DOSWASMX.BAT'))
        {
            myClass.doswasmxBatFound = true;
        }

        if (text.includes('x =='))
        {
            if (text.includes('x == 2'))
            {
                //this means we are booting into windows
                myClass.isDosMode = false;
            }            
            else
            {
                if (text.includes('x == 0'))
                {
                    //this means we explicitly selected shutdown so go to DOS
                }
                else
                {
                    //otherwise they probably picked restart
                    //so send them back to windows
                    setTimeout(() => {
                        myClass.updateAutoexecAdditional("boot c:\r\n");
                    }, 100);
                }

                //save the hard disk every time we restart/shutdown
                if (!myClass.loggedIn)
                {
                    setTimeout(() => {
                        myClass.saveDrive();    
                    }, 100);
                }

                //we are back to the dos shell
                myClass.isoMounted = false;
                myClass.floppyMounted = false;
                myClass.isDosMode = true;
            }
        }

        if (text.includes('iso drive mounted'))
        {
            //we mounted a cd
            myClass.isoMounted = true;
        }

        //emulator has started event
        if (text.includes('DEBUG_ShowMsg: pixratio 1.000')
            && myClass.loadSavestateAfterBoot) {
            console.log('detected windows started');
            myClass.loadSavestateAfterBoot = false;

            if (myClass.loggedIn && !myClass.noCloudSave)
            {
                //we give it a 5 second delay because we
                //want to wait for the windows startup sound
                setTimeout(() => {
                    myClass.loadCloud();
                }, 5000);
            }
        }

        //this means its done exporting
        if (text.includes('echo DONE'))
        {
            if (this.exportFilesRequested)
            {
                this.exportFilesRequested = false;
                setTimeout(() => {
                    let filearray = FS.readFile("/export.zip");    
                    var file = new File([filearray], "export.zip", {type: "text/plain; charset=x-user-defined"});
                    saveAs(file);
                    Module._neil_clear_autoexec();
                }, 500);
            }
        }

        //this means its done importing
        if (text.includes('echo Import Finished'))
        {
            setTimeout(() => {
                Module._neil_clear_autoexec();
            }, 500);
        }
    }

    

    async initModule(){
        myClass.initCount++;
        myClass.finishInitialization();
        console.log('module initialized');
    }

    //need to wait for both indexedDB and wasm runtime
    finishInitialization()
    {
        if (myClass.initCount == 2)
        {
            myClass.moduleInitializing = false;
            myClass.message = '';

            //create some directories we will need
            FS.mkdir('/uploaded');
            FS.mkdir('/res');
            FS.mkdir('/save');

            $('#githubDiv').show();
            this.loading = false;

        }        
    }

    uploadBrowse() {
        this.initAudio();
        document.getElementById('file-upload').click();
    }

    importBrowse() {
        document.getElementById('file-import').click();
    }

    detectSingleFileUpload(fileName) {
        let fileExtension = fileName.substr(fileName.lastIndexOf('.')).toLocaleLowerCase();
        if (!this.specialFileHandlers.includes(fileExtension))
        {
            myClass.singleFileUpload = true;
        }
    }

    uploadRom(event) {
        myClass.initAudio();
        myClass.showProgress = true;

        if (event.currentTarget.files.length == 1)
        {
            myClass.detectSingleFileUpload(event.currentTarget.files[0].name);
        }
        else if (event.currentTarget.files.length > 1)
        {
            myClass.handleMultipleFiles(event.currentTarget.files, 0);
            return;
        }

        var file = event.currentTarget.files[0];
        myClass.rom_name = file.name;
        myClass.extractBaseName();

        console.log(file);
        var reader = new FileReader();
        reader.onprogress = function (event) {
            myClass.handleProgress(event, file);
        };
        reader.onload = function (e) {
            console.log('finished loading');
            var byteArray = new Uint8Array(this.result);
            myClass.LoadEmulator(byteArray);
        }
        reader.readAsArrayBuffer(file);
    }

    async parseMultipleFiles()
    {
        console.log('parseMultipleFiles', this.multiFiles);
        this.multiFileMode = true;

        //set some baseline default
        this.rom_name = 'blank.txt';
        let firstBytes = new Uint8Array(5);
        this.extractBaseName();



        for(let i = 0; i < this.multiFiles.length; i++)
        {
            let file = this.multiFiles[i];

            if (file.name.toLocaleLowerCase().endsWith('img'))
            {
                //we prioritize the img name as the rom_name
                //because we want to be sure it uses this as the
                //hard drive when it gets to the LoadEmulator stage
                this.rom_name = file.name;
                this.extractBaseName();

                this.baseHardDrive = file.data;
                let finalByteArray = await this.loadHardDriveDiffs(file.data);
                FS.writeFile('/' + this.base_name + '.img',finalByteArray);

                this.img_loaded = true;
            }
            else if (
                file.name.toLocaleLowerCase().endsWith('iso') || 
                file.name.toLocaleLowerCase().endsWith('.cue'))
            {
                FS.writeFile('/' + file.name,file.data);
                this.isoName = file.name;

                if (file.name.toLocaleLowerCase().endsWith('.cue'))
                {
                    this.hasBinCue = true;
                    this.cueFile = file.name;    
                }

                //if we didn't find an img then use this as the rom_name
                if (!this.rom_name)
                {
                    this.rom_name = file.name;
                    this.extractBaseName();
                }
            }
            else
            {
                //except bin/cue files
                if (file.name.toLocaleLowerCase().endsWith('.bin') )
                {
                    //will handle these manually
                    FS.writeFile('/' + file.name,file.data);
                }
                else
                {
                    //put them in the uploaded folder
                    FS.writeFile('/uploaded/' + file.name,file.data);
                }
                
            }
        }

        //FREE THE MEMORY
        this.multiFiles = null;

        //we want to avoid setting the iso bytes because they were set above
        this.noIso = true;

        this.LoadEmulator(firstBytes);

    }

    handleMultipleFiles(files, index) {

        var file = files[index];
        console.log('processing file ' + (index+1) + ' of ' + files.length, file);

        var reader = new FileReader();

        reader.onprogress = function (event) {
            console.log('loaded: ' + event.loaded);
            let loaded = event.loaded;
            let total = event.total;
            let percent = (loaded / total)*100;

            loaded = Math.ceil(loaded / 1000000);
            total = Math.ceil(total / 1000000);

            let formatted = '(' + (index+1) + ' of ' + files.length + ') ' +
                file.name + ' ' + loaded + 'MB / ' + total + 'MB';
            
            document.getElementById('myProgress').style.width= percent + '%';
            document.getElementById('myProgress').innerHTML = formatted;
        };
        reader.onload = function (e) {
            var byteArray = new Uint8Array(this.result);
            myClass.multiFiles.push(
                {
                    name: file.name,
                    data: byteArray
                }
            )
            if ( (index+1)<files.length)
            {
                myClass.handleMultipleFiles(files, index + 1);
            }
            else
            {
                myClass.parseMultipleFiles();
            }

        }
        reader.readAsArrayBuffer(file);
    }


    //awful spaghetti code needs major refactoring!
    async LoadEmulator(byteArray){


        if (byteArray && byteArray.length)
        {
            this.rom_size = byteArray.length;
        }

        if (this.iso_loaded == false)
        {
            if (!this.noIso)
            {
                if (this.rom_name.toLocaleLowerCase().endsWith('.img'))
                {
                    this.baseHardDrive = byteArray;
                    let finalByteArray = await this.loadHardDriveDiffs(byteArray);
                    FS.writeFile('/' + this.base_name + '.img',finalByteArray);
                }
                else
                {
                    if (this.singleFileUpload)
                        FS.writeFile('/uploaded/' + myClass.rom_name,byteArray);
                    else
                    {
                        FS.writeFile(myClass.rom_name,byteArray);
                    }
                }
            }

            this.iso_loaded = true;



            if (this.rom_name.toLocaleLowerCase().endsWith('.img'))
            {
                //we prioritize drag/dropping an img
                //then we skip loading img
                this.img_loaded = true;
                this.noIso = true;
                this.LoadEmulator();
            }
            else if (!this.loggedIn)
            {

                if (this.dblistDisks.length == 0)
                {
                    if (this.settings.DEFAULTIMG)
                    {
                        this.load_file(this.settings.DEFAULTIMG);
                    }
                    else
                    {
                        //this means it is their initial windows installation
                        this.img_loaded = true;
                        this.initialInstallation = true;
                        this.LoadEmulator();
                    }
                }
                else
                {
                    //load their disk
                    this.loadFromDatabase(SaveTypes.Disk);
                }

            }            
            else
            {
                if (this.settings.ISOURL)
                {
                    this.load_file(this.settings.ISOURL + 'saves/' + this.base_name + '.img');
                }
                else
                {
                    this.load_file('saves/' + this.base_name + '.img');
                }
            }

            return;

        }
        if (this.img_loaded == false)
        {
            //this will be the base hard drive for applying diffs
            this.baseHardDrive = byteArray;

            let finalByteArray = await this.loadHardDriveDiffs(byteArray);
            FS.writeFile('/' + this.base_name + '.img',finalByteArray);

            this.img_loaded = true;
        }

        //write font file
        let responseText = await $.ajax({
                url: 'main.ttf',
                beforeSend: function (xhr) {
                xhr.overrideMimeType("text/plain; charset=x-user-defined");
                }
            });
        let responseBytes = new Uint8Array(responseText.length);
        for (let i = 0; i < responseText.length; i++) {
            responseBytes[i] = responseText.charCodeAt(i) & 0xff;
        }
        console.log('main.ttf',responseText.length);
        FS.writeFile('/res/arial.ttf',responseBytes);


        //write dosbox.conf
        var rando = Math.floor(Math.random() * Math.floor(100000));
        let file = './dosbox-x-for-web.conf?v=' + rando;
        responseText = await $.ajax({
            url: './' + file,
            beforeSend: function (xhr) {
                xhr.overrideMimeType("text/plain; charset=x-user-defined");
            }
        });
        console.log(file,responseText.length);


        let multiFileScript = '';
        if (this.multiFileMode)
        {
            //we want to copy the files to the C drive
            multiFileScript = 
                'mount e .\r\n' +
                'xcopy e:\\uploaded\\*.* c:\\uploaded /I /E\r\nmount -u e\r\n';
            if (this.noIso && this.isoName)
            {
                multiFileScript += 'imgmount d \"' + this.isoName + '\"\r\n';
            }
        }


        if (this.initialInstallation)
        {
            if (this.rom_name.toLocaleLowerCase().endsWith('.iso'))
            {
                responseText = responseText.replace('[autoexec]',
                    '[autoexec]\r\nimgmount d \"' + this.rom_name +
                    '\"\r\nECHO Initial Install\r\n' + 
                    'imgmake \"' + this.base_name + ".img\" -t " + this.initialHardDrive + "\r\n" +
                    'imgmount c \"' + this.base_name + ".img\"\r\nd:\r\n");
            }
            else if (this.hasBinCue)
            {
                responseText = responseText.replace('[autoexec]',
                    '[autoexec]\r\nimgmount d \"' + this.cueFile + '\"\r\n' +
                    '\"\r\nECHO Initial Install\r\n' + 
                    'imgmake \"' + this.base_name + ".img\" -t " + this.initialHardDrive + "\r\n" +
                    'imgmount c \"' + this.base_name + ".img\"\r\nd:\r\n");
            }
            else if (this.rom_name.toLocaleLowerCase().endsWith('.img'))
            {
                responseText = responseText.replace('[autoexec]',
                    '[autoexec]\r\nimgmount c \"' + this.rom_name + '\"\r\n' +
                    'c:\r\n' +
                    'boot c:');
            }
            else if (this.rom_name.toLocaleLowerCase().endsWith('.zip') ||
                     this.rom_name.toLocaleLowerCase().endsWith('.7z'))
            {
                let sanitized = this.sanitizeName(this.rom_name);

                // we want to always copy to the C drive so that 
                // Save Drive will save our changes 
                responseText = responseText.replace('[autoexec]',
                    '[autoexec]\r\nmount d \"' + this.rom_name + '\"\r\n' +
                    'imgmake \"' + this.base_name + ".img\" -t " + this.initialHardDrive + "\r\n" +
                    'imgmount c \"' + this.base_name + ".img\"\r\n" +
                    'XCOPY D:\ C:\\' + sanitized + ' /I /E\r\nmount -u d\r\n' +
                    'c:\r\ncd ' + sanitized + '\r\n');
            }
            else
            {
                responseText = responseText.replace('[autoexec]',
                    '[autoexec]\r\n' +
                    'imgmake \"' + this.base_name + ".img\" -t " + this.initialHardDrive + "\r\n" +
                    'imgmount c \"' + this.base_name + ".img\r\n" +
                    'mount e .\r\n' +
                    'e:\r\ncd uploaded\r\n'
                    //the reason we don't want to copy to the c drive on initial install
                    //is because the copy operation is super slow
                    //'xcopy e:\\uploaded\\*.* c:\\uploaded /I /E\r\nmount -u e\r\nc:\r\ncd uploaded\r\n'
                    );
            }
        }
        else if (this.noIso)
        {
            responseText = responseText.replace('[autoexec]',
                '[autoexec]\r\nimgmount c \"' + this.base_name +
                '.img\"\r\n' + multiFileScript + 'boot c:');
        }
        else if (this.rom_name.toLocaleLowerCase().endsWith('.iso'))
        {
            responseText = responseText.replace('[autoexec]',
                '[autoexec]\r\nimgmount c \"' + this.base_name +
                '.img\"\r\nimgmount d \"' + this.base_name +
                '.iso\"\r\n' + multiFileScript + 'boot c:');
        }
        else if (this.rom_name.toLocaleLowerCase().endsWith('.zip') || 
                 this.rom_name.toLocaleLowerCase().endsWith('.7z'))
        {
            let sanitized = this.sanitizeName(this.rom_name);

            responseText = responseText.replace('[autoexec]',
                '[autoexec]\r\nimgmount c \"' + this.base_name +
                '.img\"\r\nmount d \"' + this.rom_name +
                '\"\r\nXCOPY D:\ C:\\' + sanitized + ' /I /E\r\n' +
                'mount -u d\r\n' + multiFileScript + 'boot c:');
            this.winNotFoundCommands = 'cd ' + sanitized + '\r\n';
        }
        else
        {
            //if it's a single unremarkable file we just copy it to C:
            if (this.singleFileUpload)
            {
                multiFileScript = 
                    'mount e .\r\n' +
                    'xcopy e:\\uploaded\\*.* c:\\uploaded /I /E\r\nmount -u e\r\n';
            }

            //as a last resort we always atleast try to boot into windows
            responseText = responseText.replace('[autoexec]',
                '[autoexec]\r\nimgmount c \"' + this.base_name +
                '.img\"\r\n' + multiFileScript + 'boot c:');
        }

        //ram override
        responseText = responseText.replace("memsize=32","memsize=" + this.ram);

        //dos version override
        responseText = responseText.replace("ver=7.1","ver=" + this.dosVersion);
        
        console.log(responseText);
        FS.writeFile('/dosbox-x.conf',responseText);


        this.configureEmulator();
        Module.callMain();
        this.findSavestateInDatabase();
        this.beforeEmulatorStarted = false;
        this.updateAutoexecAdditional = Module.cwrap('neil_update_autoexec_additional', null, ['string']);
        this.showToast = Module.cwrap('neil_show_toast', null, ['string']);
        this.sendKey = Module.cwrap('neil_send_key', null, ['number']);
        this.updateCpuNeil = Module.cwrap('neil_update_cpu', null, ['string']);
        this.changeIso = Module.cwrap('neil_change_iso', null, ['string']);
        this.changeFloppyDisk = Module.cwrap('neil_change_floppy', null, ['string']);
        this.loadFloppyDisk = Module.cwrap('neil_load_floppy', null, ['string']);
        this.sendDosCommands = Module.cwrap('neil_send_dos_commands', null, ['string']);
    }

    sanitizeName(name){
        
        //get rid of the extension
        if (name.includes('.'))
        {
            name = name.substr(0,name.lastIndexOf('.'))
        }

        //get rid of non alphanumeric and make it uppercase
        name = name.replace(/[^0-9a-z]/gi, '').toLocaleUpperCase();

        //trim
        if (name.length > 6)
        {
            name = name.substr(0,6);
        }
        else if (name.length<3) // as long as its atleast 3 long we leave it
        {
            //fill in the gaps with random numbers
            var rando = Math.floor(Math.random() * Math.floor(100000));
            name += rando;
            if (name.length > 6) name = name.substr(0,6);
        }

        return name;
    }

    readRomProp(key){
        let myselect = document.getElementById('romselect');
        try
        {
            return myselect.options[myselect.selectedIndex].attributes[key].value;
        }
        catch(err)
        {
            return '';
        }
    }

    loadRomAndSavestate(){
        this.loadSavestateAfterBoot = true;
        this.loadRom();
    }

    extractRomName(name){
        if (name.includes('/'))
        {
            name = name.substr(name.lastIndexOf('/')+1);
        }

        return name;
    }

    async loadRom(noIso) {
        
        this.initAudio();
        

        if (noIso)
        {
            this.noIso = true;
            this.LoadEmulator();
        }
        else
        {
            let romurl = this.readRomProp("value");
            let ram = this.readRomProp("ram");
            this.rom_name = this.extractRomName(romurl);
            if (ram)
            {
                this.ram = ram;
            }
            if (this.settings.ISOURL)
            {
                romurl = this.settings.ISOURL + romurl;
            }
            this.extractBaseName();

            this.load_file(romurl);
        }
    }

    async initAudio() {

        if (!this.audioInited)
        {
            this.audioInited = true;
            this.audioContext = new AudioContext({
                latencyHint: 'interactive',
                sampleRate: 48000,
            });
            this.gainNode = this.audioContext.createGain();
            this.gainNode.gain.value = 0.5;
            this.gainNode.connect(this.audioContext.destination);
    
            //point at where the emulator is storing the audio buffer
            this.audioBufferResampled = new Int16Array(Module.HEAP16.buffer,Module._neilGetSoundBufferResampledAddress(),64000);
    
            this.audioWritePosition = 0;
            this.audioReadPosition = 0;
            this.audioBackOffCounter = 0;
    
    
            this.pcmPlayer = this.audioContext.createScriptProcessor(AUDIOBUFFSIZE, 2, 2);
            this.pcmPlayer.onaudioprocess = this.AudioProcessRecurring.bind(this);
            this.pcmPlayer.connect(this.gainNode);
        }

    }

    countFPS(){
        this.fpscounter++;
        let delta = (new Date().getTime() - this.lastCalledTime.getTime())/1000;
        if (delta>1)
        {
            this.currentfps = this.fpscounter;
            this.fpscounter = 0;
            this.lastCalledTime = new Date();

            console.log(this.currentfps);
        }
    }

    //this method keeps getting called when it needs more audio
    //data to play so we just keep streaming it from the emulator
    AudioProcessRecurring(audioProcessingEvent){

        if (this.beforeEmulatorStarted)
        {
            return;
        }

        if (this.autoKeyboard)
        {
            this.tickAutoKeyboard();
        }


        var sampleRate = audioProcessingEvent.outputBuffer.sampleRate;
        let outputBuffer = audioProcessingEvent.outputBuffer;
        let outputData1 = outputBuffer.getChannelData(0);
        let outputData2 = outputBuffer.getChannelData(1);

        this.audioWritePosition = Module._neilGetAudioWritePosition();


        //the bytes are arranged L,R,L,R,etc.... for each speaker
        for (let sample = 0; sample < AUDIOBUFFSIZE; sample++) {

            if (this.audioWritePosition != this.audioReadPosition) {
                outputData1[sample] = (this.audioBufferResampled[this.audioReadPosition] / 32768);
                outputData2[sample] = (this.audioBufferResampled[this.audioReadPosition + 1] / 32768);

                this.audioReadPosition += 2;

                //wrap back around within the ring buffer
                if (this.audioReadPosition == 64000) {
                    this.audioReadPosition = 0;
                }
            }
            else {
                //if there's nothing to play then just play silence
                outputData1[sample] = 0;
                outputData2[sample] = 0;
            }

        }

        //calculate remaining audio in buffer
        let audioBufferRemaining = 0;
        let readPositionTemp = this.audioReadPosition;
        let writePositionTemp = this.audioWritePosition;
        for(let i = 0; i < 64000; i++)
        {
            if (readPositionTemp != writePositionTemp)
            {
                readPositionTemp += 2;
                audioBufferRemaining += 2;

                if (readPositionTemp == 64000) {
                    readPositionTemp = 0;
                }
            }
        }

    }

    extractBaseName(){
        try
        {
            this.base_name = this.rom_name.substr(0,this.rom_name.lastIndexOf('.'));
        }
        catch{
            this.base_name = 'blank';
        }
    }

    async load_file(path) {

        console.log('loading ' + path);
        myClass.load_url_request(path);
    }

    load_url_request(path){

        //check cache
        let cleanPath = path.substr(path.lastIndexOf('/')+1);
        if (cleanPath.endsWith('.img'))
        {
            let baseImageName = cleanPath.replace(".img",".baseimage");
            if (myClass.dblistBaseImages.includes(baseImageName))
            {
                myClass.loadFromDatabase(SaveTypes.BaseImage);
                return;
            }
        }
        if (cleanPath.endsWith('.iso'))
        {
            if (myClass.dblistIsos.includes(cleanPath))
            {
                myClass.loadFromDatabase(SaveTypes.ISO);
                return;
            }
        }

        this.showProgress = true;

        var req = new XMLHttpRequest();
        req.open("GET", path);
        req.overrideMimeType("text/plain; charset=x-user-defined");
        req.onerror = () => console.log(`Error loading ${path}: ${req.statusText}`);
        req.responseType = "arraybuffer";

        req.onprogress = function (event) {
            let loaded = event.loaded;
            let total = event.total;
            let percent = (loaded / total)*100;

            loaded = Math.ceil(loaded / 1000000);
            total = Math.ceil(total / 1000000);

            let formatted = loaded + 'MB / ' + total + 'MB';
            
            document.getElementById('myProgress').style.width= percent + '%';
            document.getElementById('myProgress').innerHTML = formatted;
        };
        req.onload = function (e) {
            console.log('request loaded',e,req);
            var arrayBuffer = req.response; // Note: not oReq.responseText
            try{
                if (req.status==404)
                {
                    console.log('request returned 404');

                    if (myClass.loggedIn)
                    {
                        myClass.load_file(myClass.settings.DEFAULTIMG);
                    }
                }
                else if (arrayBuffer) {
                    var byteArray = new Uint8Array(arrayBuffer);
                    myClass.LoadEmulator(byteArray);
                }
                else{
                    this.lblError = 'Error downloading data. Try reloading browser.';
                    console.log('error downloading')
                    console.log(req);
                }
            }
            catch(error){
                console.log(error);
                toastr.error('Error Loading Save');
            }
        };

        req.send();
    }

    
    newRom(){
        location.reload();
    }

    onError(message){
        console.log('error triggered',event);
        if (
            !message.includes('user has exited the lock')
            )
        {
            this.lblError = message;
        }
    }

    //prevent dropdown from popping up from keyboard events
    dropdownKeyDown(e){
        e.preventDefault();
        e.stopPropagation();
    }

    fullscreen() {
        let el = document.getElementById('canvasDiv');

        if (el.webkitRequestFullScreen) {
            el.webkitRequestFullScreen();
        }
        else {
            el.mozRequestFullScreen();
        }
    }

    zoomIn(){
        this.canvasHeight += 30;
        document.getElementById('canvasDiv').style.height = + this.canvasHeight + 'px'
        localStorage.setItem('doswasmx-height', this.canvasHeight.toString());
        this.resizeCanvas();
        console.log('zoom in');
    }

    zoomOut(){
        this.canvasHeight -= 30;
        localStorage.setItem('doswasmx-height', this.canvasHeight.toString());
        this.resizeCanvas();
        console.log('zoom out');
    }

    resizeCanvas(){
        document.getElementById('canvasDiv').style.height = this.canvasHeight + 'px';
    }

    saveDrive()
    {
        let bytes = FS.readFile('/' + this.base_name + '.img'); //this is a Uint8Array
        this.saveToDatabase(bytes, SaveTypes.Disk);
    }

    readFromLocalStorage(localStorageName, name){
        if (localStorage.getItem(localStorageName))
        {
            if (localStorage.getItem(localStorageName)=="true")
                this[name] = true;
            else if (localStorage.getItem(localStorageName)=="false")
                this[name] = false;
            else
                this[name] = localStorage.getItem(localStorageName);
        }
    }

    writeToLocalStorage(localStorageName, name){

        if (typeof(this[name]) == 'boolean')
        {
            if (this[name])
                localStorage.setItem(localStorageName, 'true');
            else        
                localStorage.setItem(localStorageName, 'false');
        }
        else
        {
            localStorage.setItem(localStorageName, this[name]);
        }

    }

    retrieveSettings(){
        this.readFromLocalStorage('doswasmx-ram','ram');
        this.readFromLocalStorage('doswasmx-initialhd','initialHardDrive');
        this.readFromLocalStorage('doswasmx-dosversion','dosVersion');
    }

    saveOptions(){
        this.ram = this.ramTemp;
        this.initialHardDrive = this.initialHardDriveTemp;
        this.dosVersion = this.dosVersionTemp;

        this.writeToLocalStorage('doswasmx-ram','ram');
        this.writeToLocalStorage('doswasmx-initialhd','initialHardDrive');
        this.writeToLocalStorage('doswasmx-dosversion','dosVersion');
    }

    createDB() {

        if (window["indexedDB"]==undefined){
            console.log('indexedDB not available');
            return;
        }

        var request = indexedDB.open('DOSWASMXDB');
        request.onupgradeneeded = function (ev) {
            console.log('upgrade needed');
            let db = ev.target.result;
            let objectStore = db.createObjectStore('DOSWASMXSTATES', { autoIncrement: true });
            objectStore.transaction.oncomplete = function (event) {
                console.log('db created');
            };
        }

        request.onsuccess = function (ev) {
            var db = ev.target.result;
            var romStore = db.transaction("DOSWASMXSTATES", "readwrite").objectStore("DOSWASMXSTATES");
            try {
                //rewrote using cursor instead of getAllKeys
                //for compatibility with MS EDGE
                romStore.openCursor().onsuccess = function (ev) {
                    var cursor = ev.target.result;
                    if (cursor) {
                        let rom = cursor.key.toString();
                        if (rom.endsWith('.savestate'))
                        {
                            myClass.dblistSavestates.push(rom);
                        }
                        if (rom.endsWith('.disk'))
                        {
                            myClass.dblistDisks.push(rom);
                        }
                        if (rom.endsWith('.iso'))
                        {
                            myClass.dblistIsos.push(rom);
                        }
                        if (rom.endsWith('.baseimage'))
                        {
                            myClass.dblistBaseImages.push(rom);
                        }
                        cursor.continue();
                    }
                    else {
                        myClass.initCount++;
                        myClass.finishInitialization();
                    }
                }

            } catch (error) {
                console.log('error reading keys');
                console.log(error);
            }

        }

    }

    findSavestateInDatabase() {

        let imgKey = myClass.base_name;
        if (!myClass.loggedIn) imgKey = 'win95';
        imgKey += + '.savestate';

        myClass.dblistSavestates.forEach(save => {
            if (save == imgKey)
            {
                console.log('found savestate in indexedDB');
                myClass.noLocalSave = false;
            }
        });
    }

    
    /**
     * Description
     * @param {any} data
     * @param {SaveTypes} saveType
     * @returns {any}
     */
    saveToDatabase(data, saveType) {

        if (!window["indexedDB"]==undefined){
            console.log('indexedDB not available');
            return;
        }
        
        console.log('save to database called: ', data.length);

        var request = indexedDB.open('DOSWASMXDB');
        request.onsuccess = function (ev) {
            var db = ev.target.result;
            var transaction = db.transaction("DOSWASMXSTATES", "readwrite");
            var romStore = transaction.objectStore("DOSWASMXSTATES");
            let imgKey = myClass.base_name;
            if (!myClass.loggedIn) imgKey = 'win95';

            if (saveType == SaveTypes.Savestate)
            {
                imgKey = imgKey + '.savestate';
            }
            if (saveType == SaveTypes.Disk)
            {
                imgKey = imgKey + '.disk';
            }
            if (saveType == SaveTypes.ISO)
            {
                imgKey = imgKey + '.iso';
            }
            if (saveType == SaveTypes.BaseImage)
            {
                imgKey = imgKey + '.baseimage'
            }

            var addRequest = romStore.put(data, imgKey);
            addRequest.onsuccess = function (event) {
                console.log('data onsuccess');
                //these take a long time so we want to let the user know
                if (saveType != SaveTypes.Savestate)
                {
                    toastr.info('Please Wait...');   
                }
            };
            addRequest.onerror = function (event) {
                toastr.error('Error Saving Data');
                console.log('error adding data');
                console.log(event);
            };
            transaction.oncomplete = function(event) {
                console.log('transaction completed');
                if (saveType == SaveTypes.Savestate)
                {
                    myClass.showToast("State Saved")
                    toastr.info('State Saved');
                }
                if (saveType == SaveTypes.Disk)
                {
                    myClass.showToast("Hard Drive Saved")
                    toastr.info('Hard Drive Saved');
                }
                if (saveType == SaveTypes.BaseImage)
                {
                    myClass.showToast("Base Image Saved")
                    toastr.info('Base Image Saved');
                    myClass.baseImageSaved = true;
                    myClass.cacheIsoAndBaseImage();
                }
                if (saveType == SaveTypes.ISO)
                {
                    myClass.showToast("ISO Saved")
                    toastr.info('ISO Saved');
                    myClass.isoSaved = true;
                    myClass.cacheIsoAndBaseImage();

                }
            }
        }
    }


    /**
     * Description
     * @param {SaveTypes} saveType
     * @returns {any}
     */
    loadFromDatabase(saveType) {

        var request = indexedDB.open('DOSWASMXDB');
        request.onsuccess = function (ev) {
            var db = ev.target.result;
            var romStore = db.transaction("DOSWASMXSTATES", "readwrite").objectStore("DOSWASMXSTATES");
            let imgKey = myClass.base_name;
            if (!myClass.loggedIn) imgKey = 'win95';

            if (saveType == SaveTypes.Savestate)
            {
                imgKey = imgKey + '.savestate';
            }
            if (saveType == SaveTypes.Disk)
            {
                imgKey = imgKey + '.disk';
            }
            if (saveType == SaveTypes.ISO)
            {
                imgKey = imgKey + '.iso';
            }
            if (saveType == SaveTypes.BaseImage)
            {
                imgKey = imgKey + '.baseimage';
            }


            var rom = romStore.get(imgKey);
            rom.onsuccess = function (event) {
                if (saveType == SaveTypes.Savestate)
                {
                    let byteArray = rom.result; //Uint8Array
                    FS.writeFile('/save/1.sav',byteArray);
                    Module._neil_unserialize();
                }
                if (saveType == SaveTypes.Disk)
                {
                    if (myClass.hardDiskFallbackFromFloppy)
                    {
                        let byteArray = rom.result; //Uint8Array
                        let imgName = '/' + myClass.base_name + '.img';
                        FS.writeFile(imgName,byteArray);
                        myClass.sendDosCommands('imgmount c \"' + myClass.base_name + ".img\na:\n");
                    }
                    else if (!myClass.loggedIn)
                    {
                        let byteArray = rom.result; //Uint8Array
                        let imgName = '/' + myClass.base_name + '.img';
                        FS.writeFile(imgName,byteArray);
                        console.log('loaded drive from db: ' + imgName);
                        myClass.img_loaded = true;
                        myClass.LoadEmulator();
                    }
                    else
                    {
                        //TODO - if we are logged in then this is the
                        //base image so we need to apply the diff drive
                    }
                }
                if (saveType == SaveTypes.ISO || saveType == SaveTypes.BaseImage)
                {
                    let byteArray = rom.result; //Uint8Array
                    myClass.LoadEmulator(byteArray);
                }
            };
            rom.onerror = function (event) {
                toastr.error('error getting rom from store');
            }
        }
        request.onerror = function (ev) {
            toastr.error('error loading from db')
        }

    }

    clearHardDrive(){

        let romToDelete = 'win95.disk';

        if (!window["indexedDB"]==undefined){
            console.log('indexedDB not available');
            return;
        }
        
        var request = indexedDB.open('DOSWASMXDB');
        request.onsuccess = function (ev) {
            var db = ev.target.result;
            var transaction = db.transaction("DOSWASMXSTATES", "readwrite");
            let request = transaction.objectStore("DOSWASMXSTATES").delete(romToDelete);

            try {
                // report that the data item has been deleted
                transaction.oncomplete = function() {
                    toastr.success('Hard Drive Deleted');
                    $('#settingsModal').modal('hide');
                    myClass.dblistDisks = [];
                };

            } catch (error) {
                toastr.error('Error Deleting Disk');
                console.log(error);
            }
        }

    }


    clearDatabase() {

        var request = indexedDB.deleteDatabase('DOSWASMXDB');
        request.onerror = function (event) {
            console.log("Error deleting database.");
            toastr.error("Error deleting database");
        };

        request.onsuccess = function (event) {
            console.log("Database deleted successfully");
            toastr.error("Database deleted successfully");
        };

    }

    async unzipFile(arrayBuffer){

        const data = new Blob([ arrayBuffer ])
        let file = new File([data], 'win95.zip');

        document.getElementById('myProgress').innerHTML = 'Decompressing...';

        let zipReader = new zip.ZipReader(new zip.BlobReader(file));
        let entries = await zipReader.getEntries()
        let blob = await entries[0].getData(new zip.BlobWriter());
        let byteArray = new Uint8Array(await blob.arrayBuffer());
        document.getElementById('myProgress').innerHTML = 'Finished Decompressing';


        myClass.LoadEmulator(byteArray);
    }

    toggleFPS(){
        Module._neil_toggle_fps();
    }

    exportModal(){
        $("#exportModal").modal();
    }

    settingsModal(){

        this.ramTemp = this.ram;
        this.initialHardDriveTemp = this.initialHardDrive;
        this.dosVersionTemp = this.dosVersion;
        
        $("#settingsModal").modal();
    }

    settingsSubmit(){
        this.saveOptions();
        $('#settingsModal').modal('hide');
        toastr.info("Settings Saved");
    }

    importModal(importType){
        myClass.noCopyImport = false;
        myClass.changeCD = false;
        myClass.loadCD = false;
        myClass.changeFloppy = false;
        myClass.loadFloppy = false;
        if (importType == 'noCopy')
        {
            myClass.noCopyImport = true;
        }
        if (importType == 'changeCD')
        {
            myClass.changeCD = true;
        }
        if (importType == 'changeFloppy')
        {
            myClass.changeFloppy = true;
        }
        if (importType == 'loadFloppy')
        {
            myClass.loadFloppy = true;
        }
        if (importType == 'loadCD')
        {
            myClass.loadCD = true;
        }
        myClass.importStatus = '';
        $("#importModal").modal();
    }

    exportFiles(){
        console.log('exportFiles');
        $('#exportModal').modal('hide');
        this.exportFilesRequested = true;
        Module._neil_export_files();
    }

    saveStateLocal(){
        console.log('saveStateLocal');
        this.noLocalSave = false;
        Module._neil_serialize();
    }

    loadStateLocal(){
        console.log('loadStateLocal');
        myClass.loadFromDatabase(SaveTypes.Savestate);
    }

    //when it returns from emscripten
    SaveStateEvent()
    {
        console.log('js savestate event');
        let compressed = FS.readFile('/save/1.sav'); //this is a Uint8Array
        
        if (!myClass.loggedIn)
        {
            myClass.saveToDatabase(compressed, SaveTypes.Savestate);
            return;
        }

        var saveMessage = "Cloud State Saved";
        
        var xhr = new XMLHttpRequest;
        xhr.open("POST", this.settings.CLOUDSAVEURL + "/SendStaveState?name=" + this.base_name + '.savestate.doswasmx' + 
            "&password=" + this.password + "&emulator=doswasmx", true);
        xhr.send(compressed);

        xhr.onreadystatechange = function() {
            try{
                if (xhr.readyState === 4) {
                    let result = xhr.response;
                    if (result=="\"Success\""){
                        myClass.noCloudSave = false;
                        toastr.info(saveMessage);
                        myClass.showToast(saveMessage);
                    }else{
                        toastr.error('Error Saving Cloud Save');
                    }
                }
            }
            catch(error){
                console.log(error);
                toastr.error('Error Loading Cloud Save');
            }
            
        }
    }

    async loadHardDriveDiffs(byteArray){

        await myClass.getSaveStates();

        let promise = new Promise(function (resolve, reject) {

            let foundCloudDrive = false;

            for(let i = 0; i < myClass.allSaveStates.length; i++)
            {
                let element = myClass.allSaveStates[i];
                if (element.Name==myClass.base_name + ".doswasmx")
                {
                    foundCloudDrive = true;
                    console.log('foundCloudDrive');
                }
            }

            // we didnt find a cloud drive
            if (!foundCloudDrive)
            {
                resolve(byteArray);
                return;
            }

            toastr.info('Found Diff Drive');

            var oReq = new XMLHttpRequest();
            oReq.open("GET", myClass.settings.CLOUDSAVEURL + "/LoadStaveState?name=" + myClass.base_name + '.doswasmx' +
                "&password=" + myClass.password, true);
            oReq.responseType = "arraybuffer";

            oReq.onload = function (oEvent) {
                var arrayBuffer = oReq.response; // Note: not oReq.responseText
                try{
                    if (arrayBuffer) {
                        var byteArray = new Uint8Array(arrayBuffer);
                        myClass.applyHardDriveDiffs(byteArray, resolve);
                    }
                    else{
                        reject();
                    }
                }
                catch(error){
                    console.log(error);
                    reject();
                }
                
            };

            oReq.send(null);

        });

        return promise;
    }

    async applyHardDriveDiffs(byteArrayDiffs, resolve){
        console.log('applyHardDriveDiffs');

        let pointer = 0;

        byteArrayDiffs = await this.decompressArrayBuffer(byteArrayDiffs.buffer);

        //start with a copy of the hold hard drive
        let newHardDrive = new Uint8Array(this.baseHardDrive);

        while(pointer < byteArrayDiffs.length)
        {
            let index = byteArrayDiffs[pointer] + (byteArrayDiffs[pointer+1]*256)
		    	 + (byteArrayDiffs[pointer+2]*256*256) + (byteArrayDiffs[pointer+3]*256*256*256);
            pointer += 4;
            
            let length = byteArrayDiffs[pointer] + (byteArrayDiffs[pointer+1]*256)
		    	 + (byteArrayDiffs[pointer+2]*256*256) + (byteArrayDiffs[pointer+3]*256*256*256);
            pointer += 4;

            //apply the diffs
            for (let i = 0; i < length; i++)
            {
                newHardDrive[index] = byteArrayDiffs[pointer];
                pointer++;
                index++;
            }
        }

        resolve(newHardDrive);
    }

    async saveHardDriveDiffs(){

        //pause dosbox
        Module._neil_toggle_pause();

        this.message += 'Calculating Diffs...';
        await new Promise(resolve => {setTimeout(resolve, 20); });

        let compareHardDrive = new Uint8Array();
        compareHardDrive = FS.readFile('/' + this.base_name + '.img'); //this is a Uint8Array

        let chunkSize = 10000;
        let arrayChunks = []; //array of Uint8SubArrays each of size chunk
        
        this.diffCount = 0;
        let progressCounter = 5000000; //we update progress every 5 million
        for (let i = 0; i < this.baseHardDrive.length; i++) {
            if (this.baseHardDrive[i] != compareHardDrive[i])
            {
                let end = i + chunkSize;
                if (end >= this.baseHardDrive.length)
                {
                    end = this.baseHardDrive.length-1;
                }

                let subArray = compareHardDrive.subarray(i,end);
                arrayChunks.push(
                    {
                        index: i,
                        data: subArray
                    });

                
                i += chunkSize-1;
                this.diffCount++;

            }

            if (i > progressCounter)
            {

                let percent = Math.floor( (i / this.baseHardDrive.length)*100 );

                this.message = "Diffs: " + this.diffCount +
                ", <b>" + percent + "%</b>";

                await new Promise(resolve => {setTimeout(resolve, 20); });

                progressCounter += 5000000;
            }
        }

        
        this.arrayChunks = arrayChunks;
        console.log(arrayChunks);

        let finalsize = 0;

        for(let i = 0; i < arrayChunks.length; i++)
        {
            //8 bytes for the two ints representing index and length
            finalsize += 8;

            let chunk = arrayChunks[i];
            finalsize += chunk.data.length;
        }

        this.message = "Generating Final Array...";
        await new Promise(resolve => {setTimeout(resolve, 20); });


        let finalArray = new Uint8Array(finalsize);
        let pointer = 0;
        for(let i = 0; i < arrayChunks.length; i++)
        {
            let chunk = arrayChunks[i];
            let index = chunk.index;

            // index (little endian)
            finalArray[pointer] = index & 0xFF;
            finalArray[pointer+1] = (index >> 8) & 0xFF;
            finalArray[pointer+2] = (index >> 16) & 0xFF;
            finalArray[pointer+3] = (index >> 24) & 0xFF;

            pointer += 4;

            let length = chunk.data.length;

            // length (little endian)
            finalArray[pointer] = length & 0xFF;
            finalArray[pointer+1] = (length >> 8) & 0xFF;
            finalArray[pointer+2] = (length >> 16) & 0xFF;
            finalArray[pointer+3] = (length >> 24) & 0xFF;

            pointer += 4;

            for(let j = 0; j < chunk.data.length; j++)
            {
                finalArray[pointer] = chunk.data[j]
                pointer++;
            }
        }

        //compress drive
        finalArray = await this.compressArrayBuffer(finalArray.buffer);

        console.log('diffSize: ' + finalsize + ' compressedSize: ' + finalArray.length);
        
        if (this.doIntegrityCheck)
        {
            this.message = 'Doing Integrity Check...';
        }
        else
        {
            Module._neil_toggle_pause();
            this.message = 'Sending to server...';
        }


        var saveMessage = "Saved: " + finalArray.length.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ",");
        
        var xhr = new XMLHttpRequest;
        xhr.open("POST", this.settings.CLOUDSAVEURL + "/SendStaveState?name=" + this.base_name + '.doswasmx' + 
            "&password=" + this.password + "&emulator=doswasmx", true);
        xhr.send(finalArray);

        xhr.onreadystatechange = function() {
            try{
                if (xhr.readyState === 4) {
                    let result = xhr.response;
                    if (result=="\"Success\""){
                        toastr.info(saveMessage);
                        
                        if (myClass.doIntegrityCheck)
                        {
                            myClass.integrityCheck(compareHardDrive);
                        }
                        else
                        {
                            myClass.message = '';
                        }

                    }else{
                        toastr.error('Error Saving Cloud Save');
                    }
                }
            }
            catch(error){
                console.log(error);
                toastr.error('Error Loading Cloud Save');
            }
            
        }

    }

    async compressArrayBuffer(input) {
        //create the stream
        const cs = new CompressionStream("gzip");
        //create the writer
        const writer = cs.writable.getWriter();
        //write the buffer to the writer 
        writer.write(input);
        writer.close();
        //create the output 
        const output = [];
        const reader = cs.readable.getReader();
        let totalSize = 0;
        //go through each chunk and add it to the output
        while (true) {
          const { value, done } = await reader.read();
          if (done) break;
          output.push(value);
          totalSize += value.byteLength;
        }
        const concatenated = new Uint8Array(totalSize);
        let offset = 0;
        //finally build the compressed array and return it 
        for (const array of output) {
          concatenated.set(array, offset);
          offset += array.byteLength;
        }
        console.log('compressed', concatenated);

        return concatenated;
    }

    async decompressArrayBuffer(input) {
        //create the stream
        const ds = new DecompressionStream("gzip");
        //create the writer
        const writer = ds.writable.getWriter();
        //write the buffer to the writer thus decompressing it 
        writer.write(input);
        writer.close();
        //create the output
        const output = [];
        //create the reader
        const reader = ds.readable.getReader();
        let totalSize = 0;
        //go through each chunk and add it to the output
        while (true) {
         const { value, done } = await reader.read();
         if (done) break;
         output.push(value);
         totalSize += value.byteLength;
        }
        const concatenated = new Uint8Array(totalSize);
        let offset = 0;
        //finally build the compressed array and return it 
        for (const array of output) {
         concatenated.set(array, offset);
         offset += array.byteLength;
        }

        return concatenated;
    }

    exportHardDrive(){
        let imgName = this.base_name + '.img';
        let exportName = imgName;
        if (!this.loggedIn)
        {
            exportName = 'hdd.img';
        }
        let filearray = FS.readFile(imgName);    
        var file = new File([filearray], exportName, {type: "text/plain; charset=x-user-defined"});
        saveAs(file);
    }

    importFiles(event){
        console.log('import files');

        if (!myClass.noCopyImport)
        {
            var rando = Math.floor(Math.random() * Math.floor(1000));
            myClass.importFolderName = 'Imp' + rando;
            FS.mkdir('/' + myClass.importFolderName);
        }

        this.isSpecialHandler = false; 
        this.importedFileNames = [];
        let files = event.currentTarget.files;

        for(let i = 0; i < files.length; i++)
        {
            this.importedFileNames.push(files[i].name);
            let fileExtension = files[i].name.substr(files[i].name.lastIndexOf('.')).toLocaleLowerCase();
            if (this.specialFileHandlers.includes(fileExtension))
            {
                this.isSpecialHandler = true;
            }
        }

        myClass.processImportFiles(files, 0)
    }

    processImportFiles(files, index){
        var file = files[index];
        console.log('processing file ' + (index+1) + ' of ' + files.length, file);

        var reader = new FileReader();

        reader.onprogress = function (event) {
            let loaded = event.loaded;
            let total = event.total;

            loaded = Math.ceil(loaded / 1000000);
            total = Math.ceil(total / 1000000);

            console.log('loaded: ' + event.loaded);
            myClass.importStatus = '(' + (index+1) + ' of ' + files.length + ') ' +
                file.name + ' ' + loaded + 'MB / ' + total + 'MB';
        };
        reader.onload = function (e) {
            var byteArray = new Uint8Array(this.result);

            if (myClass.noCopyImport || myClass.isSpecialHandler || myClass.changeFloppy || myClass.loadFloppy)
            {
                FS.writeFile('/' + file.name, byteArray);
            }
            else
            {
                FS.writeFile('/' + myClass.importFolderName + '/' + file.name, byteArray);
            }

            if ( (index+1)<files.length)
            {
                myClass.processImportFiles(files, index + 1);
            }
            else
            {
                $('#importModal').modal('hide');
                if (myClass.noCopyImport)
                {
                    Module._neil_exit_to_dos();
                }
                else if (myClass.changeFloppy)
                {
                    let filename = myClass.importedFileNames[0];
                    toastr.info('changing floppy ' + filename);
                    myClass.changeFloppyDisk(filename);
                }
                else if (myClass.loadFloppy)
                {
                    let filename = myClass.importedFileNames[0];
                    toastr.info('loading floppy ' + filename);
                    myClass.loadFloppyDisk(filename);
                }
                else if (myClass.changeCD)
                {
                    for(let i = 0; i < myClass.importedFileNames.length; i++)
                    {
                        let filename = myClass.importedFileNames[i];
                        if (filename.toLocaleLowerCase().endsWith('.iso') ||
                        filename.toLocaleLowerCase().endsWith('.cue'))
                        {
                            toastr.info('changing to ' + filename);
                            myClass.changeIso(filename);
                        }
                    }
                }
                else
                {
                    let importCommands = 
                        "mount e .\r\n" +
                        "xcopy e:\\" + myClass.importFolderName +
                        "\\*.* c:" + myClass.importFolderName  + " /I /E\r\n" +
                        "mount -u e\r\n" +
                        "boot c:\r\n";

                    if (myClass.isSpecialHandler)
                    {
                        importCommands = '';

                        for(let i = 0; i < myClass.importedFileNames.length; i++)
                        {
                            let filename = myClass.importedFileNames[i];
                            if (filename.toLocaleLowerCase().endsWith('.zip') ||
                                filename.toLocaleLowerCase().endsWith('.7z'))
                            {
                                //long folder names break with xcopy
                                let importFolder = myClass.sanitizeName(filename);

                                importCommands += 'mount e \"' + filename +
                                    "\"\r\nxcopy e:\ c:\\" + importFolder + 
                                    " /i /e\r\n" +
                                    'mount -u e\r\n';
                                myClass.winNotFoundCommands = 'cd ' + importFolder + '\r\n';
                            }
                            if (filename.toLocaleLowerCase().endsWith('.iso'))
                            {
                                importCommands += 
                                    'mount -u d\r\n' + //unmount existing iso if there is one
                                    'imgmount d \"' + filename + '\"\r\n'; //mount new iso
                                myClass.winNotFoundCommands = 'd:\r\n';
                            }
                            if (filename.toLocaleLowerCase().endsWith('.cue'))
                            {
                                importCommands += 
                                    'mount -u d\r\n' + //unmount existing iso if there is one
                                    'imgmount d \"' + filename + '\"\r\n'; //mount new iso
                                myClass.winNotFoundCommands = 'd:\r\n';
                            }
                            if (filename.toLocaleLowerCase().endsWith('.img'))
                            {
                                importCommands += 
                                    'mount -u c\r\n' + //unmount existing img if there is one
                                    'imgmount c \"' + filename + '\"\r\n'; //mount new iso
                            }
                        }

                        importCommands += 
                            'boot c:\r\n'; //boot windows
                    }

                    myClass.updateAutoexecAdditional(importCommands);
                    Module._neil_exit_to_dos();
                }
            }

        }
        reader.readAsArrayBuffer(file);
    }

    exitToDos(){
        Module._neil_exit_to_dos();
    }

    cacheIsoAndBaseImage(){

        if (!this.baseImageSaved)
        {
            //pause emulator
            Module._neil_toggle_pause();
            this.saveToDatabase(this.baseHardDrive, SaveTypes.BaseImage);
            return;
        }

        if (!this.isoSaved)
        {
            try
            {
                let bytes = FS.readFile('/' + this.base_name + ".iso");
                this.saveToDatabase(bytes, SaveTypes.ISO);
                return;
            }
            catch(error){
                console.log('no iso found');
                //this means we did not have an iso                
            }
        }

        Module._neil_toggle_pause();
        
        //reset variables
        this.baseImageSaved = false;
        this.isoSaved = false;
    }

    saveCloud(){
        Module._neil_serialize();
    }

    loadCloud(){

        var oReq = new XMLHttpRequest();
        oReq.open("GET", this.settings.CLOUDSAVEURL + "/LoadStaveState?name=" + this.base_name + '.savestate.doswasmx' +
         "&password=" + this.password, true);
        oReq.responseType = "arraybuffer";

        oReq.onload = function (oEvent) {
            var arrayBuffer = oReq.response; // Note: not oReq.responseText
            try{
                if (arrayBuffer) {
                    var byteArray = new Uint8Array(arrayBuffer);
                    FS.writeFile('/save/1.sav',byteArray);
                    Module._neil_unserialize();
                }
                else{
                    toastr.error('Error Loading Cloud Save');
                }
            }
            catch(error){
                console.log(error);
                toastr.error('Error Loading Cloud Save');
            }
            
        };

        oReq.send(null);
    }

    async setupLogin() {
        //prevent submit on enter 
        $('#txtPassword').bind("keypress", function (e) {
            if (e.keyCode == 13) {
                e.preventDefault();
                myClass.loginSubmit();
                return false;
            }
        });

        let pw = localStorage.getItem('doswasmx-password');
        if (pw==null)
            this.password = '';
        else
            this.password = pw;

        if (this.password){
            await this.loginSilent();
        }
            
    }

    loginModal(){
        $("#loginModal").modal();
        this.loginModalOpened = true;
        setTimeout(() => {
            //focus on textbox
            $("#txtPassword").focus();
        }, 500);
    }

    logout(){
        this.loggedIn = false;
        this.password = '';
        localStorage.setItem('doswasmx-password', this.password);
    }

    async loginSubmit(){
        $('#loginModal').modal('hide');
        this.loginModalOpened = false;
        let result = await this.loginToServer();
        if (result=='Success'){
            toastr.success('Logged In');
            localStorage.setItem('doswasmx-password', this.password);
            await this.getSaveStates();
            this.postLoginProcess();            
        }
        else{
            toastr.error('Login Failed');
            this.password = '';
            localStorage.setItem('doswasmx-password', '');
        }
    }

    async loginSilent(){
        if (!this.hasCloud)
            return;
        
        let result = await this.loginToServer();
        if (result=='Success'){
            await this.getSaveStates();
            this.postLoginProcess();
        }
    }

    postLoginProcess(){
        //filter by .doswasmx extension and sort by date
        this.dosSaveStates = this.allSaveStates.filter((state)=>{
            return state.Name.endsWith('.savestate.doswasmx')
        });
        this.dosSaveStates.forEach(state => {
            state.Date = this.convertCSharpDateTime(state.Date);
        });
        this.dosSaveStates.sort((a,b)=>{ return b.Date.getTime() - a.Date.getTime() });
        this.loggedIn = true;
    }

    convertCSharpDateTime(initialDate) {
        let dateString = initialDate;
        dateString = dateString.substring(0, dateString.indexOf('T'));
        let timeString = initialDate.substr(initialDate.indexOf("T") + 1);
        let dateComponents = dateString.split('-');
        let timeComponents = timeString.split(':');
        let myDate = null;

        myDate = new Date(parseInt(dateComponents[0]), parseInt(dateComponents[1]) - 1, parseInt(dateComponents[2]),
            parseInt(timeComponents[0]), parseInt(timeComponents[1]), parseInt(timeComponents[2]));
        return myDate;
    }

    async loginToServer(){
        let result = await $.get(this.settings.CLOUDSAVEURL + '/Login?password=' + this.password);
        console.log('login result: ' + result);
        return result;
    }

    async getSaveStates(){
        if (!this.loggedIn)
            return;

        let result = await $.get(this.settings.CLOUDSAVEURL + '/GetSaveStates?password=' + this.password);
        console.log('getSaveStates result: ', result);
        this.allSaveStates = result;
        result.forEach(element => {
            if (element.Name==this.base_name + ".savestate.doswasmx")
                this.noCloudSave = false;
        });
    }


    
    //USE THIS FOR DOING AN INTEGRITY CHECK ON DIFFED HARD DRIVE -
    async integrityCheck(newHardDriveBytes) {

        let finalByteArray = await this.loadHardDriveDiffs(this.baseHardDrive); //hard drive with applied diffs

        //compare bytes

        this.message += 'Calculating Diffs...';
        await new Promise(resolve => {setTimeout(resolve, 20); });

        let compareHardDrive = finalByteArray;

        let chunkSize = 10000;
        let arrayChunks = []; //array of Uint8SubArrays each of size chunk
        
        this.diffCount = 0;
        let progressCounter = 5000000; //we update progress every 5 million
        for (let i = 0; i < newHardDriveBytes.length; i++) {
            if (newHardDriveBytes[i] != compareHardDrive[i])
            {
                let end = i + chunkSize;
                if (end >= newHardDriveBytes.length)
                {
                    end = newHardDriveBytes.length-1;
                }

                let subArray = compareHardDrive.subarray(i,end);
                arrayChunks.push(
                    {
                        index: i,
                        data: subArray
                    });

                
                i += chunkSize;
                this.diffCount++;

            }

            if (i > progressCounter)
            {

                let percent = Math.floor( (i / newHardDriveBytes.length)*100 );

                this.message = "Diffs: " + this.diffCount +
                ", <b>" + percent + "%</b>";

                await new Promise(resolve => {setTimeout(resolve, 20); });

                progressCounter += 5000000;
            }
        }

        console.log(arrayChunks);

        let finalsize = 0;

        for(let i = 0; i < arrayChunks.length; i++)
        {
            //8 bytes for the two ints representing index and length
            finalsize += 8;

            let chunk = arrayChunks[i];
            finalsize += chunk.data.length;
        }

        this.message = "Generating Final Array Size: " + finalsize.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ",");

        this.message = "Diffs: " + this.diffCount +
            " Final Array Size: " + finalsize.toString().replace(/\B(?=(\d{3})+(?!\d))/g, ",") +
            " <b>DONE</b>";

        console.log('integrity check results', arrayChunks, this.diffCount);
        
        if (arrayChunks.length>0)
        {
            toastr.error("Failed integrity check");
        }
        else
        {
            toastr.success("Passed integrity check");
        }

        setTimeout(() => {
            myClass.message = '';
        }, 2000);

        Module._neil_toggle_pause();

    }

    togglePause(){
        Module._neil_toggle_pause();
    }

    updateCPU(value){
        this.cpu = value;
        if (value == 'auto')
        {
            this.updateCpuNeil('cycles=auto');
        }
        else if (value == 'max')
        {
            this.updateCpuNeil('cycles=max');
        }
        else
        {
            this.updateCpuNeil('cycles=fixed ' + value);
        }
    }

    sendCtrlAltDel(){
        Module._neil_send_ctrlaltdel();
    }

    toggle16BitColorFix(){
        Module._neil_toggle_16_bit_color_fix();
    }

    toggleAlwaysUseBackbuffer(){
        Module._neil_toggle_always_use_backbuffer();
    }

    toggleAutoKeybaord(){
        this.autoKeyboard = !this.autoKeyboard;

        if (this.autoKeyboard)
        {
            this.autoKeyboardTimer = this.autoKeyboardInterval;
            toastr.info('Auto Keyboard Enabled');
        }
        else
        {
            toastr.info('Auto Keyboard Disabled');
        }
    }

    //used to automate keyboard buttons on a timer (useful for certain games)
    tickAutoKeyboard(){
        this.autoKeyboardTimer--;
        if (this.autoKeyboardTimer==0)
        {
            this.showToast("Autokeyboard...")
            
            this.sendKey(48) //F12

            setTimeout(() => {
                myClass.sendKey(52); //enter
            }, 600);

            setTimeout(() => {
                myClass.sendKey(52); //enter
            }, 3000);

            this.autoKeyboardTimer = this.autoKeyboardInterval;
        }
    }

    turboSpeed()
    {
        Module._neil_turbo();
    }
    
}


let myClass = new MyClass();
window["myApp"] = myClass; //so that I can reference from EM_ASM

window["Module"] = {
    onRuntimeInitialized: myClass.initModule,
    canvas: document.getElementById('canvas'),
    print: (text) => myClass.processPrintStatement(text),
    // printErr: (text) => myClass.print(text)
}

var script = document.createElement('script');
script.src = 'main.js'
document.getElementsByTagName('head')[0].appendChild(script);


window.onerror = function(message) {
    console.log('window.onerror',message);
    myClass.onError(message);
}

window.onunhandledrejection = function(error) {
    console.log('window.onunhandledrejection',error);
    myClass.onError(error.reason.message);
}