const Startup = (() => {

    let firstPixel = true;
    let splashPostfix = '';

    Input.on('click', 'create-button', create, false);
    Input.on('click', 'create-button-splash', create, true);

    function create(e, isSplash) {
        // If I'm creating from the splash menu, I append '-splash' so I get the corresponding values
        if (isSplash) {
            splashPostfix = '-splash';
        }
        else {
            splashPostfix = '';
        }

        console.log("New pixel");
    
        var width = Util.getValue('size-width' + splashPostfix);
        var height = Util.getValue('size-height' + splashPostfix);
        var selectedPalette = Util.getText('palette-button' + splashPostfix);
    
        newPixel(width, height);
        
        // If I'm not creating from the splash page, then this is not the first project I've created
        if (!isSplash)
            document.getElementById('new-pixel-warning').style.display = 'block';
    
        resetInput();
    
        //track google event
        if (typeof ga !== 'undefined')
            ga('send', 'event', 'Pixel Editor New', selectedPalette, width+'/'+height); /*global ga*/
    }

    /** TODO:
     *  - Remove firstPixel: it's enough to pass to newPixel whether it's been called from the splash page or not
     *  - Divide functions depending on their purpose:
     * 		- initLayers()
     * 		- initPalette()
     * 		- openLPE()
     */    

    /** Creates a new, empty file
     * 
     * @param {*} width Start width of the canvas
     * @param {*} height Start height of the canvas
     * @param {*} fileContent If fileContent != null, then the newPixel is being called from the open menu
     */
    function newPixel (width, height, fileContent = null) {
        // The palette is empty, at the beginning
        ColorModule.resetPalette();

        initLayers(width, height);
        initPalette();

        //fill background of canvas with bg color
        fillCheckerboard();
        fillPixelGrid();

        // Closing the "New Pixel dialogue"
        Dialogue.closeDialogue();
        // Updating the cursor of the current tool
        currentTool.updateCursor();

        // The user is now able to export the Pixel
        document.getElementById('export-button').classList.remove('disabled');
        documentCreated = true;

        // This is not the first Pixel anymore
        firstPixel = false;

        // Now, if I opened an LPE file
        if (fileContent != null) {
            loadLPE(fileContent);
            // Deleting the default layer
            deleteLayer(false);
        }
    }

    function initLayers(width, height) {
         // If this is the first pixel I'm creating since the app has started
         if (firstPixel) {
            // I configure the layers elements
            layerListEntry = layerList.firstElementChild;

            // Creating the first layer
            currentLayer = new Layer(width, height, canvas, layerListEntry);
            currentLayer.canvas.style.zIndex = 2;
        }
        else {
            // Deleting all the extra layers and canvases, leaving only one
            let nLayers = layers.length;
            for (let i=2; i < layers.length - nAppLayers; i++) {
                let currentEntry = layers[i].menuEntry;
                let associatedLayer;

                if (currentEntry != null) {
                    // Getting the associated layer
                    associatedLayer = getLayerByID(currentEntry.id);

                    // Deleting its canvas
                    associatedLayer.canvas.remove();

                    // Adding the id to the unused ones
                    unusedIDs.push(currentEntry.id);
                    // Removing the entry from the menu
                    currentEntry.remove();
                }
            }

            // Removing the old layers from the list
            for (let i=2; i<nLayers - nAppLayers; i++) {
                layers.splice(2, 1);
            }

            // Setting up the current layer
            layers[1] = new Layer(width, height, layers[1].canvas, layers[1].menuEntry);
            currentLayer = layers[1];
            currentLayer.canvas.style.zIndex = 2;
            
            // Updating canvas size to the new size
            for (let i=0; i<nLayers; i++) {
                layers[i].canvasSize = [width, height];
            }
        }

        // Adding the checkerboard behind it
        checkerBoard = new Layer(width, height, checkerBoardCanvas);

        // Creating the vfx layer on top of everything
        VFXLayer = new Layer(width, height, VFXCanvas);

        // Tmp layer to draw previews on
        TMPLayer = new Layer(width, height, TMPCanvas);
        
        // Pixel grid
        pixelGrid = new Layer(width, height, pixelGridCanvas);
        // Setting the general canvasSize
        canvasSize = currentLayer.canvasSize;

        if (firstPixel) {
            // Cloning the entry so that when I change something on the first layer, those changes aren't
            // propagated to the other ones
            layerListEntry = layerListEntry.cloneNode(true);
            // Adding the first layer and the checkerboard to the list of layers
            layers.push(checkerBoard);
            layers.push(currentLayer);
            layers.push(VFXLayer);
            layers.push(TMPLayer);
            layers.push(pixelGrid);
        }
    }

    function initPalette() {
        // Get selected palette
        let selectedPalette = Util.getText('palette-button' + splashPostfix);

        //remove current palette
        colors = document.getElementsByClassName('color-button');
        while (colors.length > 0) {
            colors[0].parentElement.remove();
        }

        // If the user selected a palette and isn't opening a file, I load the selected palette
        if (selectedPalette != 'Choose a palette...') {
            //if this palette isnt the one specified in the url, then reset the url
            if (!palettes[selectedPalette].specified)
            history.pushState(null, null, '/pixel-editor');
            
            //fill the palette with specified colours
            createColorPalette(palettes[selectedPalette].colors,true);
        }
        // Otherwise, I just generate 2 semirandom colours
        else {
            //this wasn't a specified palette, so reset the url
            history.pushState(null, null, '/pixel-editor');

            //generate default colors
            var fg = new Color("hsv", Math.floor(Math.random()*360), 50, 50).rgb;
            var bg = new Color("hsv", Math.floor(Math.random()*360), 80, 100).rgb;

            //convert colors to hex
            var defaultForegroundColor = Color.rgbToHex(fg);
            var defaultBackgroundColor = Color.rgbToHex(bg);

            //add colors to palette
            ColorModule.addColor(defaultForegroundColor).classList.add('selected');
            ColorModule.addColor(defaultBackgroundColor);

            //set current drawing color as foreground color
            currentLayer.context.fillStyle = '#'+defaultForegroundColor;
            currentGlobalColor = '#' + defaultForegroundColor;
            selectedPalette = 'none';
        }
    }

    // REFACTOR: should probably moved to a FileManagement class or something
    function loadLPE(fileContent) {
        // I add every layer the file had in it
        for (let i=0; i<fileContent['nLayers']; i++) {
            let layerData = fileContent['layer' + i];
            let layerImage = fileContent['layer' + i + 'ImageData'];

            if (layerData != null) {
                // Setting id
                let createdLayer = addLayer(layerData.id, false);
                // Setting name
                createdLayer.menuEntry.getElementsByTagName("p")[0].innerHTML = layerData.name;

                // Adding the image (I can do that because they're sorted by increasing z-index)
                let img = new Image();
                img.onload = function() {
                    createdLayer.context.drawImage(img, 0, 0);
                    createdLayer.updateLayerPreview();

                    if (i == (fileContent['nLayers'] - 1)) {
                        createPaletteFromLayers();
                    }
                };

                img.src = layerImage;

                // Setting visibility and lock options
                if (!layerData.isVisible) {
                    createdLayer.hide();
                }
                if (layerData.isLocked) {
                    createdLayer.lock();
                }
            }
        }
    }
    
    function resetInput() {
        //reset new form
        Util.setValue('size-width', 64);
        Util.setValue('size-height', 64);
    
        Util.setText('palette-button', 'Choose a palette...');
        Util.setText('preset-button', 'Choose a preset...');
    }

    function newFromTemplate(preset, x, y) {
        if (preset != '') {
            const presetProperties = PresetModule.propertiesOf(preset);
            Util.setText('palette-button-splash', presetProperties.palette);
            Util.setText('palette-button', presetProperties.palette);
    
            x = presetProperties.width;
            y = presetProperties.height;
        }
        newPixel(x, y);
    }

    return {
        create,
        newPixel,
        newFromTemplate
    }
})();