var overlayOpacity = 0.8;	// controls transparency of shadow overlay

var animate = true;			// toggles resizing animations
var resizeSpeed = 7;		// controls the speed of the image resizing animations (1=slowest and 10=fastest)

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

// -----------------------------------------------------------------------------------
//	Global Variables
//
var imageArray = new Array;
var activeImage;

if(animate == true){
	overlayDuration = 0.2;	// shadow fade in/out duration
	if(resizeSpeed > 10){ resizeSpeed = 10;}
	if(resizeSpeed < 1){ resizeSpeed = 1;}
	resizeDuration = (11 - resizeSpeed) * 0.15;
} else { 
	overlayDuration = 0;
	resizeDuration = 0;
}

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

//
//	Lightbox Class Declaration
//	- initialize()
//	- start()
//	- changeImage()
//	- resizeImageContainer()
//	- showImage()
//	- updateDetails()
//	- updateNav()
//	- enableKeyboardNav()
//	- disableKeyboardNav()
//	- keyboardNavAction()
//	- preloadNeighborImages()
//	- end()
//
//	Structuring of code inspired by Scott Upton (http://www.uptonic.com/)
//
var Lightbox = Class.create();

Lightbox.prototype = {
	
	// 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();

		// 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 = document.getElementsByTagName("body").item(0);
		
		var objOverlay = document.createElement("div");
		objOverlay.setAttribute('id','overlay');
		objOverlay.style.display = 'none';
		objOverlay.onclick = function() { myLightbox.end(); }
		objBody.appendChild(objOverlay);
		

		
		var objLightbox = document.createElement("div");
		objLightbox.setAttribute('id','lightbox');
		objLightbox.style.display = 'none';
		objLightbox.onclick = function(e) {	// close Lightbox is user clicks shadow overlay
			if (!e) var e = window.event;
			var clickObj = Event.element(e).id;
			if ( clickObj == 'lightbox') {
				myLightbox.end();
			}
		};		

		objBody.appendChild(objLightbox);
			
		var objOuterImageContainer = document.createElement("div");
		objOuterImageContainer.setAttribute('id','outerImageContainer');
		objLightbox.appendChild(objOuterImageContainer);
		// loklok debug alert(animate);
		// 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.
		// if(animate){ alert(Element);	
			// Element.setWidth('outerImageContainer', 250);
			// Element.setHeight('outerImageContainer', 250);			
		// } else {	 alert("2");	
			// Element.setWidth('outerImageContainer', 1);
			// Element.setHeight('outerImageContainer', 1);			
		// }
		// alert("debug");
		var objImageContainer = document.createElement("div");
		objImageContainer.setAttribute('id','imageContainer');
		objOuterImageContainer.appendChild(objImageContainer);
	
		var objLightboxImage = document.createElement("img");
		objLightboxImage.setAttribute('id','lightboxImage');
		objImageContainer.appendChild(objLightboxImage);
	
		var objHoverNav = document.createElement("div");
		objHoverNav.setAttribute('id','hoverNav');
		objImageContainer.appendChild(objHoverNav);
	
		var objPrevLink = document.createElement("a");
		objPrevLink.setAttribute('id','prevLink');
		objPrevLink.setAttribute('href','#');
		objHoverNav.appendChild(objPrevLink);
		
		var objNextLink = document.createElement("a");
		objNextLink.setAttribute('id','nextLink');
		objNextLink.setAttribute('href','#');
		objHoverNav.appendChild(objNextLink);
	
		var objLoading = document.createElement("div");
		objLoading.setAttribute('id','loading');
		objImageContainer.appendChild(objLoading);
	
		var objLoadingLink = document.createElement("a");
		objLoadingLink.setAttribute('id','loadingLink');
		objLoadingLink.setAttribute('href','#');
		objLoadingLink.onclick = function() { myLightbox.end(); return false; }
		objLoading.appendChild(objLoadingLink);
	
		var objLoadingImage = document.createElement("img");
		objLoadingImage.setAttribute('src', 'http://www.hi-mobile.net/image/himobile/loading.gif');
		objLoadingLink.appendChild(objLoadingImage);

		var objImageDataContainer = document.createElement("div");
		objImageDataContainer.setAttribute('id','imageDataContainer');
		objLightbox.appendChild(objImageDataContainer);

		var objImageData = document.createElement("div");
		objImageData.setAttribute('id','imageData');
		objImageDataContainer.appendChild(objImageData);
	
		var objImageDetails = document.createElement("div");
		objImageDetails.setAttribute('id','imageDetails');
		objImageData.appendChild(objImageDetails);
	
		var objCaption = document.createElement("span");
		objCaption.setAttribute('id','caption');
		objImageDetails.appendChild(objCaption);
	
		var objNumberDisplay = document.createElement("span");
		objNumberDisplay.setAttribute('id','numberDisplay');
		objImageDetails.appendChild(objNumberDisplay);
		
		var objBottomNav = document.createElement("div");
		objBottomNav.setAttribute('id','bottomNav');
		objImageData.appendChild(objBottomNav);
	
		var objBottomNavCloseLink = document.createElement("a");
		objBottomNavCloseLink.setAttribute('id','bottomNavClose');
		objBottomNavCloseLink.setAttribute('href','#');
		objBottomNavCloseLink.onclick = function() { myLightbox.end(); return false; }
		objBottomNav.appendChild(objBottomNavCloseLink);
	
		var objBottomNavCloseImage = document.createElement("img");
		objBottomNavCloseImage.setAttribute('src', 'http://www.hi-mobile.net/image/himobile/loading.gif');
		objBottomNavCloseLink.appendChild(objBottomNavCloseImage);
	},


	//
	// 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() {	
		if (!document.getElementsByTagName){ return; }
		var anchors = document.getElementsByTagName('a');
		var areas = document.getElementsByTagName('area');

		// loop through all anchor tags
		for (var i=0; i<anchors.length; i++){
			var anchor = anchors[i];
			
			var relAttribute = String(anchor.getAttribute('rel'));
			
			// use the string.match() method to catch 'lightbox' references in the rel attribute
			if (anchor.getAttribute('href') && (relAttribute.toLowerCase().match('lightbox'))){
				anchor.onclick = function () {myLightbox.start(this); return false;}
			}
		}

		// loop through all area tags
		// todo: combine anchor & area tag loops
		for (var i=0; i< areas.length; i++){
			var area = areas[i];
			
			var relAttribute = String(area.getAttribute('rel'));
			
			// use the string.match() method to catch 'lightbox' references in the rel attribute
			if (area.getAttribute('href') && (relAttribute.toLowerCase().match('lightbox'))){
				area.onclick = function () {myLightbox.start(this); return false;}
			}
		}
	},
	
	
	//
	//	start()
	//	Display overlay and lightbox. If image is part of a set, add siblings to imageArray.
	//
	start: function(imageLink) {	

		hideSelectBoxes();
		hideFlash();

		// stretch overlay to fill page and fade in
		var arrayPageSize = getPageSize();
		Element.setWidth('overlay', arrayPageSize[0]);
		Element.setHeight('overlay', arrayPageSize[1]);

		new Effect.Appear('overlay', { duration: overlayDuration, from: 0.0, to: overlayOpacity });
    
		imageArray = [];
		imageNum = 0;		
    
    
    
    
		if (!document.getElementsByTagName){ return; }
		var anchors = document.getElementsByTagName( imageLink.tagName);

		// if image is NOT part of a set..
		if((imageLink.getAttribute('rel') == 'lightbox')){
			// add single image to imageArray
			imageArray.push(new Array(imageLink.getAttribute('href'), imageLink.getAttribute('title')));			
		} else {
		// if image is part of a set..

			// loop through anchors, find other images in set, and add them to imageArray
			for (var i=0; i<anchors.length; i++){
				var anchor = anchors[i];
				if (anchor.getAttribute('href') && (anchor.getAttribute('rel') == imageLink.getAttribute('rel'))){
					imageArray.push(new Array(anchor.getAttribute('href'), anchor.getAttribute('title')));
				}
			}
			imageArray.removeDuplicates();
			while(imageArray[imageNum][0] != imageLink.getAttribute('href')) { imageNum++;}
		}

		// calculate top and left offset for the lightbox 
		var arrayPageScroll = getPageScroll();
		var lightboxTop = arrayPageScroll[1] + (arrayPageSize[3] / 10);
		var lightboxLeft = arrayPageScroll[0];
		Element.setTop('lightbox', lightboxTop);
		Element.setLeft('lightbox', lightboxLeft);

		Element.show('lightbox');
		
		this.changeImage(imageNum);
	},

	//
	//	changeImage()
	//	Hide most elements and preload image in preparation for resizing image container.
	//
	changeImage: function(imageNum) {	
		
		if(activeImage==undefined)
		Element.hide('imageDataContainer');
		
		
		activeImage = imageNum;	// update global var

		// hide elements during transition
		if(animate){ Element.show('loading');}
		Element.hide('lightboxImage');
		Element.hide('hoverNav');
		Element.hide('prevLink');
		Element.hide('nextLink');
		Element.hide('numberDisplay');		
		
		imgPreloader = new Image();
		
		// once image is preloaded, resize image container
		imgPreloader.onload=function(){
			Element.setSrc('lightboxImage', imageArray[activeImage][0]);
			myLightbox.resizeImageContainer(imgPreloader.width, imgPreloader.height);
			
			imgPreloader.onload=function(){};	//	clear onLoad, IE behaves irratically with animated gifs otherwise 
		}
		imgPreloader.src = imageArray[activeImage][0];
	},

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

		// get curren width and height
		this.widthCurrent = Element.getWidth('outerImageContainer');
		this.heightCurrent = Element.getHeight('outerImageContainer');

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

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

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

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

		// if new and old image are same size and no scaling transition is necessary, 
		// do a quick pause to prevent image flicker.
		if((hDiff == 0) && (wDiff == 0)){
			if (navigator.appVersion.indexOf("MSIE")!=-1){ pause(250); } else { pause(100);} 
		}

		Element.setHeight('prevLink', imgHeight);
		Element.setHeight('nextLink', imgHeight);
		Element.setWidth( 'imageDataContainer', widthNew);

		this.showImage();
	},
	
	//
	//	showImage()
	//	Display image and begin preloading neighbors.
	//
	showImage: function(){
		Element.hide('loading');
		new Effect.Appear('lightboxImage', { duration: resizeDuration, queue: 'end', afterFinish: function(){	myLightbox.updateDetails(); } });
		this.preloadNeighborImages();
	},

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

		new Effect.Parallel(
			[ new Effect.SlideDown( 'imageDataContainer', { sync: true, duration: resizeDuration, from: 1.0, to: 1.0 }), 
			  new Effect.Appear('imageDataContainer', { sync: true, duration: resizeDuration }) ], 
			{ duration: resizeDuration, afterFinish: function() {
				// update overlay size and update nav
				var arrayPageSize = getPageSize();
				Element.setHeight('overlay', arrayPageSize[1]);
				myLightbox.updateNav();
				}
			} 
		);
	},

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

		Element.show('hoverNav');				

		// if not first image in set, display prev image button
		if(activeImage != 0){
			Element.show('prevLink');
			document.getElementById('prevLink').onclick = function() {
				myLightbox.changeImage(activeImage - 1); return false;
			}
		}

		// if not last image in set, display next image button
		if(activeImage != (imageArray.length - 1)){
			Element.show('nextLink');
			document.getElementById('nextLink').onclick = function() {
				myLightbox.changeImage(activeImage + 1); return false;
			}
		}
		
		this.enableKeyboardNav();
	},

	//
	//	enableKeyboardNav()
	//
	enableKeyboardNav: function() {
		document.onkeydown = this.keyboardAction; 
	},

	//
	//	disableKeyboardNav()
	//
	disableKeyboardNav: function() {
		document.onkeydown = '';
	},

	//
	//	keyboardAction()
	//
	keyboardAction: function(e) {
		if (e == null) { // ie
			keycode = event.keyCode;
			escapeKey = 27;
		} else { // mozilla
			keycode = e.keyCode;
			escapeKey = e.DOM_VK_ESCAPE;
		}

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

	},

	//
	//	preloadNeighborImages()
	//	Preload previous and next images.
	//
	preloadNeighborImages: function(){

		if((imageArray.length - 1) > activeImage){
			preloadNextImage = new Image();
			preloadNextImage.src = imageArray[activeImage + 1][0];
		}
		if(activeImage > 0){
			preloadPrevImage = new Image();
			preloadPrevImage.src = imageArray[activeImage - 1][0];
		}
	
	},

	//
	//	end()
	//
	end: function() {
		this.disableKeyboardNav();
		Element.hide('lightbox');
		new Effect.Fade('overlay', { duration: overlayDuration});
		showSelectBoxes();
		showFlash();
	}
}

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

//
// listenKey()
//
function listenKey () {	document.onkeypress = getKey; }
	
// ---------------------------------------------------

function showSelectBoxes(){
	var selects = document.getElementsByTagName("select");
	for (i = 0; i != selects.length; i++) {
		selects[i].style.visibility = "visible";
	}
}

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

function hideSelectBoxes(){
	var selects = document.getElementsByTagName("select");
	
	for (i = 0; i != selects.length; i++) {
		selects[i].style.visibility = "hidden";
	}
	
	var selects = document.getElementsByTagName("class");
	
	for (i = 0; i != selects.length; i++) {
		selects[i].style.visibility = "hidden";
	}
	
	
}

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

function showFlash(){
	var flashObjects = document.getElementsByTagName("object");
	for (i = 0; i < flashObjects.length; i++) {
		flashObjects[i].style.visibility = "visible";
	}

	var flashEmbeds = document.getElementsByTagName("embed");
	for (i = 0; i < flashEmbeds.length; i++) {
		flashEmbeds[i].style.visibility = "visible";
	}
}

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

function hideFlash(){
	var flashObjects = document.getElementsByTagName("object");
	for (i = 0; i < flashObjects.length; i++) {
		flashObjects[i].style.visibility = "hidden";
	}

	var flashEmbeds = document.getElementsByTagName("embed");
	for (i = 0; i < flashEmbeds.length; i++) {
		flashEmbeds[i].style.visibility = "hidden";
	}

}


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

//
// pause(numberMillis)
// Pauses code execution for specified time. Uses busy code, not good.
// Help from Ran Bar-On [ran2103@gmail.com]
//

function pause(ms){
	var date = new Date();
	curDate = null;
	do{var curDate = new Date();}
	while( curDate - date < ms);
}
/*
function pause(numberMillis) {
	var curently = new Date().getTime() + sender;
	while (new Date().getTime();	
}
*/
// ---------------------------------------------------



function initLightbox() { myLightbox = new Lightbox(); }
Event.observe(window, 'load', initLightbox, false);