// -------------------------------------------------------------------
// Image Thumbnail Viewer Script- By Dynamic Drive, available at: http://www.dynamicdrive.com
// Last updated: July 7th, 2008- Fixed enlarged image not showing in IE sometimes
// -------------------------------------------------------------------

var thumbnailviewer={
	//Enable fading animation?
	enableTitle: false,
	//Enable fading animation?
	enableAnimation: true, 
	//Define HTML for footer interface
	definefooter: '<div class="footerbar">Затвори <strong>X</strong></div>', 
	//Define HTML for "loading" div
	defineLoading: '<img src="images/loading.gif" /> Loading Image...',
	scrollbarwidth: 16,
	imageSize: '600px',
	verName: 'ver',
	opacitystring: '',
	//Array to hold links with rel="thumbnail"
	targetlinks:[], 

	//write out HTML for Image Thumbnail Viewer plus loading div
	createthumbBox:function()
	{
		document.write('<div id="thumbBox" onClick="thumbnailviewer.closeit()"><div id="thumbImage"></div>' + this.definefooter + '</div>')
		document.write('<div id="thumbLoading">' + this.defineLoading + '</div>')
		this.thumbBox = document.getElementById("thumbBox");
		//Reference div that holds the shown image
		this.thumbImage = document.getElementById("thumbImage");
		//Reference "loading" div that will be shown while image is fetched
		this.thumbLoading=document.getElementById("thumbLoading");
		//create reference to common "body" across doctypes
		this.standardbody = (document.compatMode=="CSS1Compat")? document.documentElement : document.body;
	},

	//Centers a div element on the page
	centerDiv:function(divobj)
	{ 
		var ie = document.all && !window.opera;
		var dom=document.getElementById;
		var scroll_top=(ie)? this.standardbody.scrollTop : window.pageYOffset;
		var scroll_left=(ie)? this.standardbody.scrollLeft : window.pageXOffset;
		var docwidth=(ie)? this.standardbody.clientWidth : window.innerWidth-this.scrollbarwidth;
		var docheight=(ie)? this.standardbody.clientHeight: window.innerHeight;
		var docheightcomplete=(this.standardbody.offsetHeight>this.standardbody.scrollHeight)? this.standardbody.offsetHeight : this.standardbody.scrollHeight //Full scroll height of document
		//width of div element
		var objwidth=divobj.offsetWidth;
		//height of div element
		var objheight=divobj.offsetHeight;
		//Vertical position of div element: Either centered, or if element height larger than viewpoint height, 10px from top of viewpoint
		var topposition=(docheight>objheight)? scroll_top+docheight/2-objheight/2+"px" : scroll_top+10+"px";
		//Center div element horizontally
		divobj.style.left=docwidth/2-objwidth/2+"px";
		divobj.style.top=Math.floor(parseInt(topposition))+"px";
		divobj.style.visibility="visible";
	},

	//Show ThumbBox div
	showthumbBox:function()
	{
		//Hide "loading" div
		thumbnailviewer.thumbLoading.style.visibility="hidden";
		this.centerDiv(this.thumbBox);
		if (this.enableAnimation)
		{
			//Starting opacity value
			this.currentopacity=0.1;
			this.opacitytimer=setInterval("thumbnailviewer.opacityanimation()", 20);
		}
	},

	//Load image function that gets attached to each link on the page with rel="thumbnail"
	loadimage:function(link)
	{ 
		//if thumbox is visible on the page already
		if (this.thumbBox.style.visibility=="visible") 
		{
			//Hide it first (not doing so causes triggers some positioning bug in Firefox
			this.closeit();
		}
		
		//See the direction
		var horDirection = true;
		if (link.getAttribute("id") && link.getAttribute("id") == this.verName)
		{
			horDirection = false;
		}
		//Construct HTML for shown image
		var imageHTML = '';
		if (horDirection)
		{
			imageHTML='<img width="' + this.imageSize + '" src="'+link.getAttribute("href")+'" style="'+this.opacitystring+'" alt="Изображение" title="Затвори" />';
		}
		else
		{
			imageHTML='<img height="' + this.imageSize + '" src="'+link.getAttribute("href")+'" style="'+this.opacitystring+'" alt="Изображение" title="Затвори" />';
		}
		
		//Use title attr of the link as description?
		if (this.enableTitle && link.getAttribute("title")) 
		{
			imageHTML+='<br />'+link.getAttribute("title");
		}
		//Center and display "loading" div while we set up the image to be shown
		this.centerDiv(this.thumbLoading);
		//Populate thumbImage div with shown image's HTML (while still hidden)
		this.thumbImage.innerHTML=imageHTML;
		//Reference shown image itself
		this.featureImage=this.thumbImage.getElementsByTagName("img")[0];
		if (this.featureImage.complete)
		{
			thumbnailviewer.showthumbBox();
		}
		else
		{
			//When target image has completely loaded
			this.featureImage.onload=function()
			{ 
				//Display "thumbbox" div to the world!
				thumbnailviewer.showthumbBox();
			}
		}
		//Target IE5.0 browsers only. Address IE image cache not firing onload bug: panoramio.com/blog/onload-event/
		if (document.all && !window.createPopup) 
		{
			this.featureImage.src=link.getAttribute("href");
		}
		//If an error has occurred while loading the image to show
		this.featureImage.onerror=function()
		{ 
			//Hide "loading" div, game over
			thumbnailviewer.thumbLoading.style.visibility="hidden";
		}
	},

	//Sets the opacity of "thumbimage" div per the passed in value setting (0 to 1 and in between)
	setimgopacity:function(value)
	{
		var targetobject=this.featureImage;
		//IE syntax
		if (targetobject.filters && targetobject.filters[0])
		{
			if (typeof targetobject.filters[0].opacity=="number") 
			{
				//IE6
				targetobject.filters[0].opacity=value*100;
			}
			else
			{
				//IE 5.5
				targetobject.style.filter="alpha(opacity="+value*100+")";
			}
		}
		else if (typeof targetobject.style.MozOpacity!="undefined")
		{
			//Old Mozilla syntax
			targetobject.style.MozOpacity=value;
		}
		else if (typeof targetobject.style.opacity!="undefined")
		{
			//Standard opacity syntax
			targetobject.style.opacity=value;
		}
		else
		{
			//Non of the above, stop opacity animation
			this.stopanimation();
		}
	},

	//Gradually increase opacity function
	opacityanimation:function()
	{
		this.setimgopacity(this.currentopacity);
		this.currentopacity+=0.1;
		if (this.currentopacity>1)
		{
			this.stopanimation();
		}
	},

	stopanimation:function()
	{
		if (typeof this.opacitytimer!="undefined")
		{
			clearInterval(this.opacitytimer);
		}
	},

	//Close "thumbbox" div function
	closeit:function()
	{
		this.stopanimation();
		this.thumbBox.style.visibility="hidden";
		this.thumbImage.innerHTML="";
		this.thumbBox.style.left="-2000px";
		this.thumbBox.style.top="-2000px";
	},

	//Clean up routine on page unload
	cleanup:function()
	{
		this.thumbLoading=null;
		if (this.featureImage) 
		{
			this.featureImage.onload=null;
		}
		this.featureImage=null;
		this.thumbImage=null;
		for (var i=0; i<this.targetlinks.length; i++)
		{
			this.targetlinks[i].onclick=null
		}
		this.thumbBox=null
	},
	
	//assign a function to execute to an event handler (ie: onunload)
	dotask:function(target, functionref, tasktype)
	{
		var tasktype=(window.addEventListener)? tasktype : "on"+tasktype
		if (target.addEventListener)
		{
			target.addEventListener(tasktype, functionref, false);
		}
		else if (target.attachEvent)
		{
			target.attachEvent(tasktype, functionref)
		}
	},

	//Initialize thumbnail viewer script by scanning page and attaching appropriate function to links with rel="thumbnail"
	init:function()
	{
		if (!this.enableAnimation) 
		{
			this.opacitystring="";
		}
		else
		{
			//Include the opacity
			if (navigator.appName == "Microsoft Internet Explorer")
			{
				this.opacitystring = 'filter:progid:DXImageTransform.Microsoft.alpha(opacity=10); -moz-opacity: 0.1; opacity: 0.1';
			}
			else
			{
				this.opacitystring = '-moz-opacity: 0.1; opacity: 0.1';
			}
		}
		var pagelinks=document.getElementsByTagName("a")
		for (var i=0; i<pagelinks.length; i++)
		{
			if (pagelinks[i].getAttribute("rel") && pagelinks[i].getAttribute("rel")=="thumbnail")
			{
				pagelinks[i].onclick=function()
				{
					//Stop any currently running fade animation on "thumbbox" div before proceeding
					thumbnailviewer.stopanimation();
					//Load image
					thumbnailviewer.loadimage(this);
					return false;
				}
				//store reference to target link
				this.targetlinks[this.targetlinks.length]=pagelinks[i];
			}
		}
		//Reposition "thumbbox" div when page is resized
		this.dotask(window, function(){if (thumbnailviewer.thumbBox.style.visibility=="visible") thumbnailviewer.centerDiv(thumbnailviewer.thumbBox)}, "resize");
	}
}

//Output HTML for the image thumbnail viewer
thumbnailviewer.createthumbBox();
//Initialize script on page load
thumbnailviewer.dotask(window, function(){thumbnailviewer.init()}, "load");
thumbnailviewer.dotask(window, function(){thumbnailviewer.cleanup()}, "unload")