// -----------------------------------------------------------------------------------
//
//	Lightbox v2.04
//	by Lokesh Dhakar - http://www.lokeshdhakar.com
//	Last Modification: 2/9/08
//
//	For more information, visit:
//	http://lokeshdhakar.com/projects/lightbox2/
//
//	Licensed under the Creative Commons Attribution 2.5 License - http://creativecommons.org/licenses/by/2.5/
//  	- Free for use in both personal and commercial projects
//		- Attribution requires leaving author name, author link, and the license info intact.
//	
//  Thanks: Scott Upton(uptonic.com), Peter-Paul Koch(quirksmode.com), and Thomas Fuchs(mir.aculo.us) for ideas, libs, and snippets.
//  		Artemy Tregubenko (arty.name) for cleanup and help in updating to latest ver of proto-aculous.
//
// -----------------------------------------------------------------------------------
/*

    Table of Contents
    -----------------
    Configuration

    Lightbox Class Declaration
    - initialize()
    - updateImageList()
    - start()
    - changeImage()
    - resizeImageContainer()
    - showImage()
    - updateDetails()
    - updateNav()
    - enableKeyboardNav()
    - disableKeyboardNav()
    - keyboardAction()
    - preloadNeighborImages()
    - end()
    - getWindowSize()
    - getPageSize()
    
    Function Calls
    - document.observe()
   
*/
// -----------------------------------------------------------------------------------

//
//  Configurationl
//
LightboxOptions = Object.extend({
    fileLoadingImage:        '/assets/img/lightbox/loading.gif',     
    fileBottomNavCloseImage: '/assets/img/lightbox/close.gif',
	directLinkImage:		 '/assets/img/lightbox/directlink.gif',

	directLinkTitle: 'View image outside lightbox',
	closeTitle:      'Close',
	nextLinkTitle:   'Next image in group',
	prevLinkTitle:   'Previous image in group',

    overlayOpacity: 0.8,   // controls transparency of shadow overlay

    animate: true,         // toggles resizing animations
    resizeSpeed: 8,        // controls the speed of the image resizing animations (1=slowest and 10=fastest)

    borderSize: 10,         //if you adjust the padding in the CSS, you will need to update this variable

	// When grouping images this is used to write: Image # of #.
	// Change it for non-english localization
	labelImage: "Image",
	labelOf: "of"
}, window.LightboxOptions || {});

// -----------------------------------------------------------------------------------

var Lightbox = Class.create();

Lightbox.prototype = {
    imageArray: [],
    activeImage: undefined,
    
    // initialize()
    // Constructor runs on completion of the DOM loading. Calls updateImageList and then
    // the function inserts html at the bottom of the page which is used to display the shadow 
    // overlay and the image container.
    //
    initialize: function() {    
        
        this.updateImageList();
        
        this.keyboardAction = this.keyboardAction.bindAsEventListener(this);

        if (LightboxOptions.resizeSpeed > 10) LightboxOptions.resizeSpeed = 10;
        if (LightboxOptions.resizeSpeed < 1)  LightboxOptions.resizeSpeed = 1;

	    this.resizeDuration = LightboxOptions.animate ? ((11 - LightboxOptions.resizeSpeed) * 0.15) : 0;
	    this.overlayDuration = LightboxOptions.animate ? 0.2 : 0;  // shadow fade in/out duration

        // When Lightbox starts it will resize itself from 250 by 250 to the current image dimension.
        // If animations are turned off, it will be hidden as to prevent a flicker of a
        // white 250 by 250 box.
        var size = (LightboxOptions.animate ? 250 : 1) + 'px';
        

        // Code inserts html at the bottom of the page that looks similar to this:
        //
        //  <div id="overlay"></div>
        //  <div id="lightbox">
        //      <div id="outerImageContainer">
        //          <div id="imageContainer">
        //              <img id="lightboxImage">
        //              <div style="" id="hoverNav">
        //                  <a href="#" id="prevLink"></a>
        //                  <a href="#" id="nextLink"></a>
        //              </div>
        //              <div id="loading">
        //                  <a href="#" id="loadingLink">
        //                      <img src="images/loading.gif">
        //                  </a>
        //              </div>
        //          </div>
        //      </div>
        //      <div id="imageDataContainer">
        //          <div id="imageData">
        //              <div id="imageDetails">
        //                  <span id="caption"></span>
        //                  <span id="numberDisplay"></span>
        //              </div>
        //              <div id="bottomNav">
        //                  <a href="#" id="bottomNavClose">
        //                      <img src="images/close.gif">
        //                  </a>
        //              </div>
        //          </div>
        //      </div>
        //  </div>

        var objBody = $$('body')[0];

		objBody.appendChild(Builder.node('div',{id:'overlay'}));
	
		objBody.appendChild(Builder.node('div',{id:'loading'}, 
			Builder.node('img', {src: LightboxOptions.fileLoadingImage})
		));
			
        objBody.appendChild(Builder.node('div',{id:'lightbox'}, [
            Builder.node('div',{id:'outerImageContainer'}, 
                Builder.node('div',{id:'imageContainer'}, [
                    Builder.node('img',{id:'lightboxImage'}), 
                    Builder.node('div',{id:'hoverNav'}, [
                        Builder.node('a',{id:'prevLink', href: '#' }),
                        Builder.node('a',{id:'nextLink', href: '#' })
                    ]),
                ])
            ),
            Builder.node('div', {id:'imageDataContainer'},
                Builder.node('div',{id:'imageData'}, [
                    Builder.node('div',{id:'imageDetails'}, [
                        Builder.node('span',{id:'caption'}),
                        Builder.node('span',{id:'numberDisplay'})
                    ]),
                    Builder.node('div',{id:'bottomNav'}, [
                        Builder.node('a',{id:'bottomNavClose', href: '#' },
                            Builder.node('img', { src: LightboxOptions.fileBottomNavCloseImage })
                        ),
                        Builder.node('a',{id:'directLink', href: '#' },
                        	Builder.node('img', { src: LightboxOptions.directLinkImage })
                        )
                    ])
                ])
            )
        ]));


		$('overlay').hide().observe('click', (function() { this.end(); }).bind(this));
		$('lightbox').hide().observe('click', (function(event) { if (event.element().id == 'lightbox') this.end(); }).bind(this));
		$('loading').hide().observe('click', (function() { event.stop(); this.end(); }).bind(this));
		$('outerImageContainer').setStyle({ width: size, height: size });
		$('prevLink').observe('click', (function(event) { event.stop(); this.changeImage(this.activeImage - 1); }).bindAsEventListener(this));
		$('nextLink').observe('click', (function(event) { event.stop(); this.changeImage(this.activeImage + 1); }).bindAsEventListener(this));
		$('bottomNavClose').observe('click', (function(event) { event.stop(); this.end(); }).bind(this));
		$('directLink').observe('click', (function(event) {}).bind(this));

        var th = this;
        (function(){
            var ids = 
                'overlay lightbox loading outerImageContainer imageContainer lightboxImage hoverNav prevLink nextLink ' + 
                'imageDataContainer imageData imageDetails caption numberDisplay bottomNav bottomNavClose directLink';   
            $w(ids).each(function(id){ th[id] = $(id); });
        }).defer();
    },

    //
    // updateImageList()
    // Loops through anchor tags looking for 'lightbox' references and applies onclick
    // events to appropriate links. You can rerun after dynamically adding images w/ajax.
    //
    updateImageList: function() {   
        this.updateImageList = Prototype.emptyFunction;

        document.observe('click', (function(event){
            var target = event.findElement('a[rel^=lightbox]') || event.findElement('area[rel^=lightbox]');
            if (target) {
                event.stop();
                this.start(target);
            }
        }).bind(this));
    },
    
    //
    //  start()
    //  Display overlay and lightbox. If image is part of a set, add siblings to imageArray.
    //
    start: function(imageLink) {    

        $$('select', 'object', 'embed').each(function(node){ node.style.visibility = 'hidden' });

        // stretch overlay to fill page and fade in
        var arrayPageSize = this.getPageSize();
        $('overlay').setStyle({ width: arrayPageSize[0] + 'px', height: arrayPageSize[1] + 'px' });

        new Effect.Appear(this.overlay, { duration: this.overlayDuration, from: 0.0, to: LightboxOptions.overlayOpacity });

        this.imageArray = [];
        var imageNum = 0;       

        if ((imageLink.rel == 'lightbox')){
            // if image is NOT part of a set, add single image to imageArray
            this.imageArray.push([imageLink.href, imageLink.title]);         
        } else {
            // if image is part of a set..
            this.imageArray = 
                $$(imageLink.tagName + '[href][rel="' + imageLink.rel + '"]').
                collect(function(anchor){ return [anchor.href, anchor.title]; }).
                uniq();
            
            while (this.imageArray[imageNum][0] != imageLink.href) { imageNum++; }
        }

        this.changeImage(imageNum);
    },

	centreImageContainer: function(imageWidth, imageHeight) {
        // calculate top and left offset for the lightbox 
        var arrayPageScroll = document.viewport.getScrollOffsets();

        var lightboxTop = arrayPageScroll[1];
        
        var borderPad = 44;

		// work out offset of lightbox from top of viewport
		// IE and Firefox don't like document.viewport.getHeight()
		// IE returns 0, Firefox seems to return the height of the whole document, not the viewport
        //var offset = (document.viewport.getHeight() / 20);
        var offset = (this.getWindowSize()[1] - (imageHeight + borderPad)) / 2;

		// push up to take lightbox bottom into account
		offset -= this.imageDataContainer.getHeight() / 2;
        
        // ensure there is some offset at least; looks poop otherwise
        if (offset <= 0) { offset = 10; }
        lightboxTop += offset;
        
        var lightboxLeft = arrayPageScroll[0];
        this.lightbox.setStyle({ top: lightboxTop + 'px', left: lightboxLeft + 'px' }).show();
    },

    //
    //  changeImage()
    //  Hide most elements and preload image in preparation for resizing image container.
    //
    changeImage: function(imageNum) {   
        
        this.activeImage = imageNum; // update global var

		// show loading graphic
        if (LightboxOptions.animate) {
        	var arrayPageScroll = document.viewport.getScrollOffsets();
        	var loadingTop = arrayPageScroll[1];
        	loadingTop += (this.getWindowSize()[1] - (this.loading.getHeight())) / 2;
        	var loadingLeft = arrayPageScroll[0];
        	this.loading.setStyle({ top: loadingTop + 'px', left: loadingLeft + 'px' }).show();
        }
        
        // hide elements during transition
        this.lightboxImage.hide();
        this.hoverNav.hide();
        this.prevLink.hide();
        this.nextLink.hide();
		// HACK: Opera9 does not currently support scriptaculous opacity and appear fx
        //this.imageDataContainer.setStyle({opacity: .0001});
        this.imageDataContainer.hide();

        this.numberDisplay.hide();      
        
		// oops, hiding this helps
		this.caption.hide();
		
		//this.directLink.setHref(this.imageArray[this.activeImage][0]);
		
		this.directLink.href = this.imageArray[this.activeImage][0];
		
		this.directLink.title =     LightboxOptions.directLinkTitle;
		this.bottomNavClose.title = LightboxOptions.closeTitle;
		this.nextLink.title =       LightboxOptions.nextLinkTitle;
		this.prevLink.title =       LightboxOptions.prevLinkTitle;
		
		var imgPreloader = new Image();
        
        // once image is preloaded, resize image container


        imgPreloader.onload = (function(){
            this.lightboxImage.src = this.imageArray[this.activeImage][0];
            this.centreImageContainer(imgPreloader.width, imgPreloader.height);
            this.resizeImageContainer(imgPreloader.width, imgPreloader.height);
        }).bind(this);
        imgPreloader.src = this.imageArray[this.activeImage][0];
    },

    //
    //  resizeImageContainer()
    //
    resizeImageContainer: function(imgWidth, imgHeight) {
        // get new width and height
        var widthNew  = (imgWidth  + LightboxOptions.borderSize * 2);
        var heightNew = (imgHeight + LightboxOptions.borderSize * 2);

		// effects give me more trouble than they're worth
		this.outerImageContainer.setStyle({ width: widthNew + 'px', height: heightNew + 'px' });

		this.prevLink.setStyle({ height: imgHeight + 'px' });
		this.nextLink.setStyle({ height: imgHeight + 'px' });
		this.imageDataContainer.setStyle({ width: widthNew + 'px' }).show();

		this.showImage();
    },
    
    //
    //  showImage()
    //  Display image and begin preloading neighbors.
    //
    showImage: function(){
        this.loading.hide();

        this.updateDetails();

		//this.lightboxImage.show();
		new Effect.Appear(this.lightboxImage, { 
            duration: this.resizeDuration, 
            queue: 'end', 
            afterFinish: (function(){ }).bind(this) 
        });
        
        this.preloadNeighborImages();
    },

    //
    //  updateDetails()
    //  Display caption, image number, and bottom nav.
    //
    updateDetails: function() {
    
        // if caption is not null
        if (this.imageArray[this.activeImage][1] != ""){
            this.caption.update(this.imageArray[this.activeImage][1]).show();
        }
        
        // if image is part of set display 'Image x of x' 
        if (this.imageArray.length > 1){
            this.numberDisplay.update( LightboxOptions.labelImage + ' ' + (this.activeImage + 1) + ' ' + LightboxOptions.labelOf + '  ' + this.imageArray.length).show();
        }

		this.updateNav();
    },

    //
    //  updateNav()
    //  Display appropriate previous and next hover navigation.
    //
    updateNav: function() {

        this.hoverNav.show();               

        // if not first image in set, display prev image button
        if (this.activeImage > 0) this.prevLink.show();

        // if not last image in set, display next image button
        if (this.activeImage < (this.imageArray.length - 1)) this.nextLink.show();
        
        this.enableKeyboardNav();
    },

    //
    //  enableKeyboardNav()
    //
    enableKeyboardNav: function() {
        document.observe('keydown', this.keyboardAction); 
    },

    //
    //  disableKeyboardNav()
    //
    disableKeyboardNav: function() {
        document.stopObserving('keydown', this.keyboardAction); 
    },

    //
    //  keyboardAction()
    //
    keyboardAction: function(event) {
        var keycode = event.keyCode;

        var escapeKey;
        if (event.DOM_VK_ESCAPE) {  // mozilla
            escapeKey = event.DOM_VK_ESCAPE;
        } else { // ie
            escapeKey = 27;
        }

        var key = String.fromCharCode(keycode).toLowerCase();
        
        if (key.match(/x|o|c/) || (keycode == escapeKey)){ // close lightbox
            this.end();
        } else if ((key == 'p') || (keycode == 37)){ // display previous image
            if (this.activeImage != 0){
                this.disableKeyboardNav();
                this.changeImage(this.activeImage - 1);
            }
        } else if ((key == 'n') || (keycode == 39)){ // display next image
            if (this.activeImage != (this.imageArray.length - 1)){
                this.disableKeyboardNav();
                this.changeImage(this.activeImage + 1);
            }
        }
    },

    //
    //  preloadNeighborImages()
    //  Preload previous and next images.
    //
    preloadNeighborImages: function(){
        var preloadNextImage, preloadPrevImage;
        if (this.imageArray.length > this.activeImage + 1){
            preloadNextImage = new Image();
            preloadNextImage.src = this.imageArray[this.activeImage + 1][0];
        }
        if (this.activeImage > 0){
            preloadPrevImage = new Image();
            preloadPrevImage.src = this.imageArray[this.activeImage - 1][0];
        }
    
    },

    //
    //  end()
    //
    end: function() {
        this.disableKeyboardNav();
        this.lightbox.hide();
        this.loading.hide();
        new Effect.Fade(this.overlay, { duration: this.overlayDuration });
        $$('select', 'object', 'embed').each(function(node){ node.style.visibility = 'visible' });
    },

    //
    //  getWindowSize()
    //
    getWindowSize: function() {
	        
		var windowWidth, windowHeight;
		
		if (self.innerHeight) {	// all except Explorer
			if(document.documentElement.clientWidth){
				windowWidth = document.documentElement.clientWidth; 
			} else {
				windowWidth = self.innerWidth;
			}
			windowHeight = self.innerHeight;
		} else if (document.documentElement && document.documentElement.clientHeight) { // Explorer 6 Strict Mode
			windowWidth = document.documentElement.clientWidth;
			windowHeight = document.documentElement.clientHeight;
		} else if (document.body) { // other Explorers
			windowWidth = document.body.clientWidth;
			windowHeight = document.body.clientHeight;
		}	

		return [windowWidth,windowHeight];
	},
	
	//
    //  getPageSize()
    //
    getPageSize: function() {
	        
	     var xScroll, yScroll;
		
		if (window.innerHeight && window.scrollMaxY) {	
			xScroll = window.innerWidth + window.scrollMaxX;
			yScroll = window.innerHeight + window.scrollMaxY;
		} else if (document.body.scrollHeight > document.body.offsetHeight){ // all but Explorer Mac
			xScroll = document.body.scrollWidth;
			yScroll = document.body.scrollHeight;
		} else { // Explorer Mac...would also work in Explorer 6 Strict, Mozilla and Safari
			xScroll = document.body.offsetWidth;
			yScroll = document.body.offsetHeight;
		}
		
		var windowSize = this.getWindowSize();
		var windowWidth = windowSize[0];
		var windowHeight = windowSize[1];
		
		// for small pages with total height less then height of the viewport
		if(yScroll < windowHeight){
			pageHeight = windowHeight;
		} else { 
			pageHeight = yScroll;
		}
	
		// for small pages with total width less then width of the viewport
		if(xScroll < windowWidth){	
			pageWidth = xScroll;		
		} else {
			pageWidth = windowWidth;
		}

		return [pageWidth,pageHeight];
	}
}

document.observe('dom:loaded', function () { new Lightbox(); });