// ---
/*
	JaS is developed by Robert Nyman, http://www.robertnyman.com
	For more information, please see http://www.robertnyman.com/jas
*/
var JaS = {
	// Customization parameters
	imagePath : "pictures/",
	images : [
		["1.jpg", "<h2>Picture One</h2>Lorem ipsum dolor sit amet, consectetuer adipiscing elit. In placerat mi in turpis. Donec in urna tristique metus lobortis posuere. In hac habitasse platea dictumst. Ut ac enim vitae ligula malesuada laoreet. Nunc malesuada tristique odio. Proin ornare aliquet nulla."],
		["2.jpg", "<h2>Picture One</h2>Lorem ipsum dolor sit amet, consectetuer adipiscing elit. In placerat mi in turpis. Donec in urna tristique metus lobortis posuere. In hac habitasse platea dictumst. Ut ac enim vitae ligula malesuada laoreet. Nunc malesuada tristique odio. Proin ornare aliquet nulla."],
		["3.jpg", "<h2>Picture One</h2>Lorem ipsum dolor sit amet, consectetuer adipiscing elit. In placerat mi in turpis. Donec in urna tristique metus lobortis posuere. In hac habitasse platea dictumst. Ut ac enim vitae ligula malesuada laoreet. Nunc malesuada tristique odio. Proin ornare aliquet nulla."],
		["4.jpg", "<h2>Picture One</h2>Lorem ipsum dolor sit amet, consectetuer adipiscing elit. In placerat mi in turpis. Donec in urna tristique metus lobortis posuere. In hac habitasse platea dictumst. Ut ac enim vitae ligula malesuada laoreet. Nunc malesuada tristique odio. Proin ornare aliquet nulla."],
		["5.jpg", "<h2>Picture One</h2>Lorem ipsum dolor sit amet, consectetuer adipiscing elit. In placerat mi in turpis. Donec in urna tristique metus lobortis posuere. In hac habitasse platea dictumst. Ut ac enim vitae ligula malesuada laoreet. Nunc malesuada tristique odio. Proin ornare aliquet nulla."],
		["6.jpg", "<h2>Picture One</h2>Lorem ipsum dolor sit amet, consectetuer adipiscing elit. In placerat mi in turpis. Donec in urna tristique metus lobortis posuere. In hac habitasse platea dictumst. Ut ac enim vitae ligula malesuada laoreet. Nunc malesuada tristique odio. Proin ornare aliquet nulla."]
	],
	fadeContainerId : "jas-container",
	imageContainerId : "jas-image",
	imageTextContainerId : "jas-image-text",
	previousLinkId : "previous-image",
	nextLinkId : "next-image",
	imageCounterId : "image-counter",
	startSlideShowId : "start-slideshow",
	stopSlideShowId : "stop-slideshow",	
	dimBackgroundOverlayId : "jas-dim-overlay",
	dimBackgroundId : "dim-background",
	noDimBackgroundId : "no-dim-background",
	thumbnailContainerId: "jas-thumbnails",
	tagsContainerId: "jas-tags",
	tagsSelectAllId: "jas-select-all-tags",
	useImageText : true,
	useThumbnails : true,
	allowDimmedBackground : true,
	automaticallyDimBackgroundWhenSlideShow : true,
	useTags : true,
	useKeyboardShortcuts : true,	
	useFadingIn : true,
	useFadingOut : true,
	useFadeWhenNotSlideshow : false,
	useFadeForSlideshow : true,
	useFadeAtInitialLoad : false,
	fadeIncrement : 0.1,	
	fadeInterval : 100, // Milliseconds	
	timeForSlideInSlideshow : 1500, // Milliseconds	
	
	// JaS function parameters
	allImages : null,
	currentImages : null,
	fadeContainer : null,
	imageContainer : null,
	imageTextContainer : null,
	previousLink : null,
	nextLink : null,
	dimBackgroundOverlay : null,
	dimBackgroundLink : null,
	noDimBackgroundLink : null,
	dimmingActivated : false,
	imageCounter : null,
	startSlideShowLink : null,
	stopSlideShowLink : null,
	thumbnailContainer : null,
	thumbnailCollection : [],
	currentThumbnailSelected : null,
	tagsContainer : null,
	tagsSelectAll : null,
	tagsList : null,
	tags : [],
	tagsCheckboxes : [],
	selectAllTags : true,
	imageText : null,
	imageText : "",
	imageSource : "",
	imageIndex : 0,
	fadingIn : true,
	fadeLevel : 0,
	fadeEndLevel : 1,
	fadeTimer : null,
	hasOpacitySupport : false,
	useMSFilter : false,
	useMSCurrentStyle : false,
	slideshowIsSupported : false,
	slideshowIsPlaying : false,
	functionAfterFade : null,
	isInitialLoad : false,
	
	init : function (){
    	if($){
			this.fadeContainer = $(this.fadeContainerId);
			this.imageContainer = $(this.imageContainerId);
			this.slideshowIsSupported = this.fadeContainer && this.imageContainer;
			if(this.slideshowIsSupported){
				this.allImages = this.images;
				this.currentImages = this.images;
				if(this.useImageText){
					this.imageTextContainer = $(this.imageTextContainerId);
					if(!this.imageTextContainer){
						this.useImageText = false;
					}
				}
				this.hasOpacitySupport = typeof this.fadeContainer.style.filter != "undefined" || typeof this.fadeContainer.style.opacity != "undefined";
				this.useMSFilter = typeof this.fadeContainer.style.filter != "undefined";
				this.useMSCurrentStyle = typeof this.fadeContainer.currentStyle != "undefined";
				
				this.previousLink = $(this.previousLinkId);
				this.previousLink.onclick = JaS.previousLinkClick;
				this.nextLink = $(this.nextLinkId);
				this.nextLink.onclick = JaS.nextLinkClick;
				this.imageCounter = $(this.imageCounterId);
				this.startSlideShowLink = $(this.startSlideShowId);
				if(this.startSlideShowLink){
					this.startSlideShowLink.style.display = "inline";
				}
				this.startSlideShowLink.onclick = JaS.startSlideShowClick;
				this.stopSlideShowLink = $(this.stopSlideShowId);
				if(this.stopSlideShowLink){
					this.stopSlideShowLink.style.display = "none";
				}
				this.stopSlideShowLink.onclick = JaS.stopSlideshowClick;
				
				if(this.allowDimmedBackground){
					this.dimBackgroundOverlay = $(this.dimBackgroundOverlayId);
					this.dimBackgroundLink = $(this.dimBackgroundId);
					this.noDimBackgroundLink = $(this.noDimBackgroundId);
					if(this.dimBackgroundOverlay && this.dimBackgroundLink && this.noDimBackgroundLink){
						this.dimBackgroundLink.onclick = JaS.dimBackgroundClick;
						this.noDimBackgroundLink.onclick = JaS.noDimackgroundClick;
						this.noDimBackgroundLink.style.display = "none";
						this.dimmingActivated = true;
					}
				}
				
				if(this.useKeyboardShortcuts){
					document.onkeydown = JaS.documentKeyDown;
				}
				
				this.thumbnailContainer = $(this.thumbnailContainerId);
				if(this.useThumbnails && this.thumbnailContainer){
					this.createThumbnails();
				}
				
				this.tagsContainer = $(this.tagsContainerId);
				if(this.useTags && this.tagsContainer){
					this.tagsSelectAll = $(this.tagsSelectAllId);
					if(this.tagsSelectAll){
						this.tagsSelectAll.onclick = JaS.tagsSelectAllClick;
						this.createTagList();
					}
				}
				
				this.isInitialLoad = true;
				this.setImage();
				this.isInitialLoad = false;
			}
		}
	},
	
	previousLinkClick : function(oEvent){
		var oEvent = (typeof oEvent != "undefined")? oEvent : event;
		JaS.preventDefaultEventBehavior(oEvent);
		JaS.previousImage();
	},
	
	nextLinkClick : function(oEvent){
		var oEvent = (typeof oEvent != "undefined")? oEvent : event;
		JaS.preventDefaultEventBehavior(oEvent);
		JaS.nextImage();
	},
	
	startSlideShowClick : function(oEvent){
		var oEvent = (typeof oEvent != "undefined")? oEvent : event;
		JaS.preventDefaultEventBehavior(oEvent);
		JaS.startSlideshow();
	},
	
	stopSlideshowClick : function(oEvent){
		var oEvent = (typeof oEvent != "undefined")? oEvent : event;
		JaS.preventDefaultEventBehavior(oEvent);
		JaS.stopSlideshow();
	},
	
	dimBackgroundClick : function(oEvent){
		var oEvent = (typeof oEvent != "undefined")? oEvent : event;
		JaS.preventDefaultEventBehavior(oEvent);
		JaS.dimBackground();
	},
	
	documentKeyDown : function(oEvent){
		var oEvent = (typeof oEvent != "undefined")? oEvent : event;
		JaS.applyKeyboardNavigation(oEvent);
	},
	
	tagsSelectAllClick : function (oEvent){
		JaS.tagsSelectAll = this.checked;
		JaS.markAllTags();
	},
	
	noDimackgroundClick : function(oEvent){
		var oEvent = (typeof oEvent != "undefined")? oEvent : event;
		JaS.preventDefaultEventBehavior(oEvent);
		JaS.noDimBackground();
	},
	
	setImage : function (){
		if(this.currentImages.length > 0){
			this.imageContainer.style.visibility = "visible";
			this.imageSource = this.currentImages[this.imageIndex][0];
			this.imageText = this.currentImages[this.imageIndex][1];
			if(this.useFadingOut && (this.slideshowIsPlaying && this.useFadeForSlideshow) || (!this.slideshowIsPlaying && this.useFadeWhenNotSlideshow) && (this.useFadeAtInitialLoad && this.isInitialLoad || !this.isInitialLoad)){
				this.fadeOut();
			}
			else{
				this.displayImageCount();
				this.imageContainer.setAttribute("src", (this.imagePath + this.imageSource));
				this.setImageText();
				this.previousLink.style.visibility = (this.imageIndex > 0)? "visible" : "hidden";
				this.nextLink.style.visibility = (this.imageIndex < (this.currentImages.length - 1))? "visible" : "hidden";
				if((this.useFadeAtInitialLoad && this.isInitialLoad || !this.isInitialLoad) && ((this.slideshowIsPlaying && this.useFadeForSlideshow) || (!this.slideshowIsPlaying && this.useFadeWhenNotSlideshow))){
					this.fadeIn();
				}
			}
			if(this.useThumbnails){
				this.markCurrentThumbnail();
			}
		}
		else{
			this.imageSource = "";
			this.imageText = "";
			this.displayImageCount();
			this.imageContainer.style.visibility = "hidden";
			this.setImageText();
		}
	},
	
	displayImageCount : function (){
    	if(this.imageCounter){
			this.imageCounter.innerHTML = (((this.currentImages.length > 0)? this.imageIndex : -1) + 1) + " / " + this.currentImages.length;
		}
	},
	
	nextImage : function (){
		if(this.imageIndex < (this.currentImages.length - 1)){
			++this.imageIndex;
			this.setImage();
		}
		else if(this.slideshowIsPlaying){
			this.stopSlideshow();
			this.imageIndex = 0;
			this.setImage();
		}
	},
	
	previousImage : function (){
		if(this.imageIndex > 0){
			--this.imageIndex;
			this.setImage();
		}         
	},

	setImageText : function (){
		this.imageTextContainer.setAttribute("alt", this.imageText);
    	if(this.useImageText && typeof this.imageText == "string"){
			this.imageTextContainer.innerHTML = this.imageText;
		}
	},
	
	setDimBackgroundSize : function(){
         var oDimBackground = this.dimBackgroundOverlay.style;
         var intWidth = document.body.offsetWidth;
         var intXScroll = (typeof window.pageXOffset != "undefined")? window.pageXOffset : document.body.scrollLeft;
         var intHeight = (typeof window.innerHeight != "undefined")? window.innerHeight : (document.documentElement)? document.documentElement.clientHeight : document.body.clientHeight;
         var intYScroll = (typeof window.window.pageYOffset != "undefined")? window.window.pageYOffset : (document.documentElement)? document.documentElement.scrollTop : document.documentElement.scrollTop;
         oDimBackground.width = intWidth + intXScroll + "px";
         oDimBackground.height = intHeight + intYScroll + "px";
	},
	
	dimBackground : function (){
         this.setDimBackgroundSize();
         this.dimBackgroundOverlay.style.display = "block";
		 this.noDimBackgroundLink.style.display = "inline";		
	},
	
	noDimBackground : function (fromStopSlideshow){
		this.dimBackgroundOverlay.style.display = "none";
		this.noDimBackgroundLink.style.display = "none";
		if(!fromStopSlideshow){
			this.stopSlideshow();
		}
	},
		
	startSlideshow : function (){
		if(this.currentImages.length > 0){
			this.startSlideShowLink.style.display = "none";
			this.stopSlideShowLink.style.display = "inline";
			this.slideshowIsPlaying = true;
			this.fadeTimer = setTimeout("JaS.nextImage()", JaS.timeForSlideInSlideshow);
			if(this.dimmingActivated  && this.automaticallyDimBackgroundWhenSlideShow){
				this.dimBackground();
			}
		}
	},
	
	stopSlideshow : function (){
		if(this.currentImages.length > 0){
			this.startSlideShowLink.style.display = "inline";
			this.stopSlideShowLink.style.display = "none";
			this.slideshowIsPlaying = false;
			this.setFadeParams(false, 1, 0);
			this.setFade();
			clearTimeout(this.fadeTimer);
			if(this.dimmingActivated && this.automaticallyDimBackgroundWhenSlideShow){
				this.noDimBackground(true);
			}
		}
	},
	
	fadeIn : function (){
		this.setFadeParams(true, 0, 1);
		this.functionAfterFade = null;
		this.fade();
		if(this.slideshowIsPlaying){
			this.functionAfterFade = "this.startSlideshow()";
		}
	},
	
	fadeOut : function (){
		this.setFadeParams(false, 1, 0);
		this.functionAfterFade = "this.fadeOutDone()";
		this.fade();
	},
	
	fadeOutDone : function (){
        this.displayImageCount();
		this.imageContainer.setAttribute("src", (this.imagePath + this.imageSource));
		this.setImageText();
		if(this.useFadingIn){
			this.fadeIn();
		}
		else{
			this.fadeLevel = 1;
			this.setFade();
		}
	},
	
	fade : function (){
		if((this.fadingIn && this.fadeLevel < this.fadeEndLevel) || !this.fadingIn && this.fadeLevel > this.fadeEndLevel){
			this.fadeLevel = (this.fadingIn)? this.fadeLevel + this.fadeIncrement : this.fadeLevel - this.fadeIncrement;
			// This line is b/c of a floating point bug in JavaScript
			this.fadeLevel = Math.round(this.fadeLevel * 10) / 10;
			this.setFade();
			this.fadeTimer = setTimeout("JaS.fade()", this.fadeInterval);
		}
		else{
			clearTimeout(this.fadeTimer);
			if(this.functionAfterFade){
				eval(this.functionAfterFade);
			}
		}
	},
	
	setFade : function (){
		if(this.useMSFilter){
			this.fadeContainer.style.filter = "progid:DXImageTransform.Microsoft.Alpha(opacity=" + (this.fadeLevel * 100) + ")";
		}
		else{
			this.fadeContainer.style.opacity = this.fadeLevel;
		}
	},
	
	setFadeParams : function (bFadingIn, intStartLevel, intEndLevel){
		this.fadingIn = bFadingIn;
		this.fadeLevel = intStartLevel;
		this.fadeEndLevel = intEndLevel;
	},
	
	createThumbnails : function (){
		this.thumbnailContainer.innerHTML = "";
		this.thumbnailCollection = [];
    	var oThumbnailsList = document.createElement("ul");
		var oListItem;
		var oThumbnail;
		var oCurrentImage;
		for(var i=0; i<this.currentImages.length; i++){
        	oCurrentImage = this.currentImages[i];
			oListItem = document.createElement("li");
			oThumbnail = document.createElement("img");
			oThumbnail.setAttribute("id", ("jas-thumbnail-" + i));
			oThumbnail.setAttribute("src", (this.imagePath + oCurrentImage[0]));
			oThumbnail.setAttribute("alt", oCurrentImage[1]);
			oThumbnail.setAttribute("title", oCurrentImage[1]);
			oThumbnail.onclick = JaS.thumbnailClick;
			this.thumbnailCollection.push(oThumbnail);
			oListItem.appendChild(oThumbnail);
			oThumbnailsList.appendChild(oListItem);			
        }
		this.thumbnailContainer.appendChild(oThumbnailsList);
		if(this.thumbnailCollection.length > 0){
			this.markCurrentThumbnail();
		}
		if(this.slideshowIsPlaying){
			this.stopSlideshow();
		}
	},
	
	thumbnailClick : function (oEvent){
		JaS.imageIndex = parseInt(this.getAttribute("id").replace(/\D*(\d+)$/, "$1"), 10);
		JaS.setImage();
	},
	
	markCurrentThumbnail : function (){
		if(this.currentThumbnailSelected){
	        this.currentThumbnailSelected.className = "";
			// Sometimes, in IE, the image loses its reference to its parent
			if(this.currentThumbnailSelected.parentNode){
				this.currentThumbnailSelected.parentNode.className = "";
			}
		}
		this.currentThumbnailSelected = this.thumbnailCollection[this.imageIndex];
		this.currentThumbnailSelected.className = "selected";
		this.currentThumbnailSelected.parentNode.className = "selected-parent";
	},
	
	createTagList : function (){
		var strCurrentTag;
		var arrCurrentTag;
		var oRegExp;
		for(var i=0; i<this.images.length; i++){
			arrCurrentTag = this.images[i][2].replace(/\s*(,)\s*/,  "$1").split(",");
			for(var j=0; j<arrCurrentTag.length; j++){
            	strCurrentTag = arrCurrentTag[j];
				oRegExp = new RegExp(strCurrentTag, "i");
				if(this.tags.toString().search(oRegExp) == -1){
					this.tags.push(strCurrentTag);
				}
            }
        }
		this.tagsList = document.createElement("ul");
		var oListItem;
		var oTagCheckbox;
		var oLabel;
		for(var k=0; k<this.tags.length; k++){
			oTag = this.tags[k];
			oListItem = document.createElement("li");
			oTagCheckbox = document.createElement("input");
			oTagCheckbox.setAttribute("type", "checkbox");
			oTagCheckbox.setAttribute("id", ("jas-" + oTag));
			oTagCheckbox.setAttribute("value", oTag);
			oTagCheckbox.checked = true;
			oTagCheckbox.onclick = JaS.tagCheckboxClick;
			oLabel = document.createElement("label");
			oLabel.setAttribute("for", ("jas-" + oTag));
			oLabel.innerHTML = oTag;
			this.tagsCheckboxes.push(oTagCheckbox);
			oListItem.appendChild(oTagCheckbox);
			oListItem.appendChild(oLabel);
			this.tagsList.appendChild(oListItem);
		}
		this.tagsContainer.appendChild(this.tagsList);
		// This loop is necessary since IE can only mark checkboxes as checked after they've been added to the document
		for(var l=0; l<this.tagsCheckboxes.length; l++){
			this.tagsCheckboxes[l].checked = true;		
		}
	},
	
	tagCheckboxClick : function (oEvent){
		JaS.applyTagFilter();
	},
	
	applyTagFilter : function (){
		this.currentImages = [];
		var arrCurrentTags = [];
		var oCheckbox;
		for(var i=0; i<this.tagsCheckboxes.length; i++){
        	oCheckbox = this.tagsCheckboxes[i];
			if(oCheckbox.checked){
				arrCurrentTags.push(oCheckbox.value);
			}
        }
		var oRegExp;
		var oImage;
		for(var j=0; j<this.images.length; j++){
        	oImage = this.images[j];
			for(var k=0; k<arrCurrentTags.length; k++){
				oRegExp = new RegExp(arrCurrentTags[k], "i");
				if(oImage[2].search(oRegExp) != -1){
					this.currentImages.push(oImage);
					break;
				}
			}
        }
		
		if(this.useThumbnails){
			this.createThumbnails();
		}
		this.imageIndex = 0;
		this.setImage();
	},
	
	markAllTags : function (){
		for(var i=0; i<this.tagsCheckboxes.length; i++){
			this.tagsCheckboxes[i].checked = this.tagsSelectAll;
        }
		this.applyTagFilter();
	},
	
	closeSession : function (oEvent){
		JaS = null;
		delete JaS;
	},
	
	applyKeyboardNavigation : function (oEvent){
    	var intKeyCode = oEvent.keyCode;
    	if(!oEvent.altKey){
			switch(intKeyCode){
				case 32:
					this.slideshowIsPlaying = (this.slideshowIsPlaying)? false : true;
					if(this.slideshowIsPlaying){
						this.startSlideshow();
					}
					else{
						this.stopSlideshow();
					}
					this.preventDefaultEventBehavior(oEvent);
					break;
				case 37:
				case 38:
					this.previousImage();
					this.preventDefaultEventBehavior(oEvent);
					break;
				case 39:
				case 40:
					this.nextImage();
					this.preventDefaultEventBehavior(oEvent);
					break;
			}
		}
	},
	
	preventDefaultEventBehavior : function (oEvent){
		if(oEvent){
			oEvent.returnValue = false;
			if(oEvent.preventDefault){
				oEvent.preventDefault();
			}
		}
	}
};
// ---
addEvent(window, "load", function(){JaS.init();}, false);
addEvent(window, "unload", function(){JaS.closeSession();}, false);
// ---
// Utility functions
function addEvent(oObject, strEvent, oFunction, bCapture){
	if(oObject){
		if(oObject.addEventListener){
			oObject.addEventListener(strEvent, oFunction, bCapture);
		}
		else if(window.attachEvent){
			oObject.attachEvent(("on" + strEvent), oFunction)
		}
	}
}
// ---
function $(strId){
	return document.getElementById(strId);
}
// ---
if(typeof Array.prototype.push != "function"){
	Array.prototype.push = ArrayPush;
	function ArrayPush(value){
		this[this.length] = value;
	}
}
// ---