var JaS = {
	// Customization parameters
	imagePath : "jas/",
	images : [
		["IMG1.jpg",],
		["IMG2.jpg",],
		["IMG3.jpg",],
		["IMG4.jpg", ],
		["IMG5.jpg", ],
		["IMG6.jpg",],
		["IMG7.jpg", ],
		["IMG8.jpg", ],
		["IMG9.jpg",],
		["IMG10.jpg", ],
		["IMG11.jpg",],
	],
	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",
	thumbnailContainerId: "jas-thumbnails",
	tagsContainerId: "jas-tags",
	tagsSelectAllId: "jas-select-all-tags",
	useImageText : true,
	useThumbnails : 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,
	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(document.getElementById){
			this.fadeContainer = document.getElementById(this.fadeContainerId);
			this.imageContainer = document.getElementById(this.imageContainerId);
			this.slideshowIsSupported = this.fadeContainer && this.imageContainer;
			if(this.slideshowIsSupported){
				this.allImages = this.images;
				this.currentImages = this.images;
				if(this.useImageText){
					this.imageTextContainer = document.getElementById(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 = document.getElementById(this.previousLinkId);
				this.previousLink.onclick = function(oEvent){
					var oEvent = (typeof oEvent != "undefined")? oEvent : event;
					JaS.preventDefaultEventBehavior(oEvent);
					JaS.previousImage();
				};
				this.nextLink = document.getElementById(this.nextLinkId);
				this.nextLink.onclick = function(oEvent){
					var oEvent = (typeof oEvent != "undefined")? oEvent : event;
					JaS.preventDefaultEventBehavior(oEvent);
					JaS.nextImage();
				};
				this.imageCounter = document.getElementById(this.imageCounterId);

				if(this.useKeyboardShortcuts){
					document.onkeydown = function(oEvent){
						var oEvent = (typeof oEvent != "undefined")? oEvent : event;
						JaS.applyKeyboardNavigation(oEvent);
					};
				}

				this.thumbnailContainer = document.getElementById(this.thumbnailContainerId);
				if(this.useThumbnails && this.thumbnailContainer){
					this.createThumbnails();
				}

				this.tagsContainer = document.getElementById(this.tagsContainerId);
				if(this.useTags && this.tagsContainer){
					this.tagsSelectAll = document.getElementById(this.tagsSelectAllId);
					if(this.tagsSelectAll){
						this.tagsSelectAll.onclick = function (oEvent){
							JaS.tagsSelectAll = this.checked;
							JaS.markAllTags();
						};
						this.createTagList();
					}
				}

				this.isInitialLoad = true;
				this.setImage();
				this.isInitialLoad = false;
			}
		}
	},

	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.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){
				
			}
		}
		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();
		}
	},


	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);
		}
	},

	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);
		}
	},

	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;
	},


	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);
// ---
// 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)
		}
	}
}
// ---
if(typeof Array.prototype.push != "function"){
	Array.prototype.push = ArrayPush;
	function ArrayPush(value){
		this[this.length] = value;
	}
}
