LightboxOptions = Object.extend({
	fileLoadingImage:		'/_design/lightbox/loading.gif',	 
	fileBottomNavCloseImage: '/_design/lightbox/closelabel.gif',
	overlayOpacity: 0.8,   // controls transparency of shadow overlay
	animate: true,		 // toggles resizing animations
	resizeSpeed: 7,		// 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
	labelImage: "Image",
	labelOf: "of"
}, window.LightboxOptions || {});

var Lightbox = Class.create();

Lightbox.prototype = {
	imageArray: [],
	activeImage: undefined,

	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

		var size = (LightboxOptions.animate ? 250 : 1) + 'px';

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

		objBody.appendChild(Builder.node('div',{id:'overlay'}));

		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:'loading'}, 
						Builder.node('a',{id:'loadingLink', href: '#' }, 
							Builder.node('img', {src: LightboxOptions.fileLoadingImage})
						)
					)
				])
			),
			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 })
						)
					)
				])
			)
		]));

		$('overlay').hide().observe('click', (function() { this.end(); }).bind(this));
		$('lightbox').hide().observe('click', (function(event) { if (event.element().id == 'lightbox') 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));
		$('loadingLink').observe('click', (function(event) { event.stop(); this.end(); }).bind(this));
		$('bottomNavClose').observe('click', (function(event) { event.stop(); this.end(); }).bind(this));

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

	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: function(imageLink) {	

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

		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')){
			this.imageArray.push([imageLink.href, imageLink.title]);		 
		} else {
			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++; }
		}

		var arrayPageScroll = document.viewport.getScrollOffsets();
		var lightboxTop = arrayPageScroll[1] + (document.viewport.getHeight() / 10);
		var lightboxLeft = arrayPageScroll[0];
		this.lightbox.setStyle({ top: lightboxTop + 'px', left: lightboxLeft + 'px' }).show();
		
		this.changeImage(imageNum);
	},

	changeImage: function(imageNum) {   
		
		this.activeImage = imageNum; // update global var

		if (LightboxOptions.animate) this.loading.show();
		this.lightboxImage.hide();
		this.hoverNav.hide();
		this.prevLink.hide();
		this.nextLink.hide();
		this.imageDataContainer.setStyle({opacity: .0001});
		this.numberDisplay.hide();	  
		
		var imgPreloader = new Image();
		
		// once image is preloaded, resize image container


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

	//
	//  resizeImageContainer()
	//
	resizeImageContainer: function(imgWidth, imgHeight) {

		// get current width and height
		var widthCurrent  = this.outerImageContainer.getWidth();
		var heightCurrent = this.outerImageContainer.getHeight();

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

		// scalars based on change from old to new
		var xScale = (widthNew  / widthCurrent)  * 100;
		var yScale = (heightNew / heightCurrent) * 100;

		// calculate size difference between new and old image, and resize if necessary
		var wDiff = widthCurrent - widthNew;
		var hDiff = heightCurrent - heightNew;

		if (hDiff != 0) new Effect.Scale(this.outerImageContainer, yScale, {scaleX: false, duration: this.resizeDuration, queue: 'front'}); 
		if (wDiff != 0) new Effect.Scale(this.outerImageContainer, xScale, {scaleY: false, duration: this.resizeDuration, delay: this.resizeDuration}); 

		var timeout = 0;
		if ((hDiff == 0) && (wDiff == 0)){
			timeout = 100;
			if (Prototype.Browser.IE) timeout = 250;   
		}

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

			this.showImage();
		}).bind(this).delay(timeout / 1000);
	},
	
	showImage: function(){
		this.loading.hide();
		new Effect.Appear(this.lightboxImage, { 
			duration: this.resizeDuration, 
			queue: 'end', 
			afterFinish: (function(){ this.updateDetails(); }).bind(this) 
		});
		this.preloadNeighborImages();
	},

	updateDetails: function() {
	
		if (this.imageArray[this.activeImage][1] != ""){
			this.caption.update(this.imageArray[this.activeImage][1]).show();
		}
		
		if (this.imageArray.length > 1){
			this.numberDisplay.update( LightboxOptions.labelImage + ' ' + (this.activeImage + 1) + ' ' + LightboxOptions.labelOf + '  ' + this.imageArray.length).show();
		}

		new Effect.Parallel(
			[ 
				new Effect.SlideDown(this.imageDataContainer, { sync: true, duration: this.resizeDuration, from: 0.0, to: 1.0 }), 
				new Effect.Appear(this.imageDataContainer, { sync: true, duration: this.resizeDuration }) 
			], 
			{ 
				duration: this.resizeDuration, 
				afterFinish: (function() {
					// update overlay size and update nav
					var arrayPageSize = this.getPageSize();
					this.overlay.setStyle({ height: arrayPageSize[1] + 'px' });
					this.updateNav();
				}).bind(this)
			} 
		);
	},

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

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

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

		var escapeKey;
		if (event.DOM_VK_ESCAPE) {
			escapeKey = event.DOM_VK_ESCAPE;
		} else {
			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: 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: function() {
		this.disableKeyboardNav();
		this.lightbox.hide();
		new Effect.Fade(this.overlay, { duration: this.overlayDuration });
		$$('select', 'object', 'embed').each(function(node){ node.style.visibility = 'visible' });
	},

	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 {
			xScroll = document.body.offsetWidth;
			yScroll = document.body.offsetHeight;
		}
		
		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;
		}	
		
		if(yScroll < windowHeight){
			pageHeight = windowHeight;
		} else { 
			pageHeight = yScroll;
		}
	
		if(xScroll < windowWidth){	
			pageWidth = xScroll;		
		} else {
			pageWidth = windowWidth;
		}

		return [pageWidth,pageHeight];
	}
}

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