// IXF1.11 :: Image cross-fade 
// *****************************************************
// DOM scripting by brothercake -- http://www.brothercake.com/
//******************************************************
//global object
var ixf = { 'clock' : null, 'count' : 1, 'movecount' : 1 }
/*******************************************************



/*****************************************************************************
 List the images that need to be cached
*****************************************************************************/

ixf.imgs = Array();
ixf.hcontainer;
ixf.direction = 0;
ixf.directionx;
ixf.directiony;

function cacheImages () {
	ixf.imgs = pictures;
	
	/*****************************************************************************
	*****************************************************************************/
	
	//cache the images
	ixf.imgsLen = ixf.imgs.length;
	ixf.cache = [];
	for(var i=0; i<ixf.imgsLen; i++)
	{
		ixf.cache[i] = new Image;
		ixf.cache[i].src = ixf.imgs[i];
	}
}

function getElementsByClass(searchClass,node,tag){
		var classElements = new Array();
		if ( node == null )
			node = document;
		if ( tag == null )
			tag = '*';
		var els = node.getElementsByTagName(tag);
		var elsLen = els.length;
		var pattern = new RegExp("(^|\\s)"+searchClass+"(\\s|$)");
		for (i = 0, j = 0; i < elsLen; i++) {
			if ( pattern.test(els[i].className) ) {
				classElements[j] = els[i];
				j++;
			}
		}
		return classElements;
}


//crossfade setup function
function crossfade()
{
	ixf.hcontainer = getElementsByClass('movecontainer',document,'div')[0];
	counter++;
	quot = (counter%(pictures.length));

	//if the timer is not already going
	if(ixf.clock == null)
	{
		//copy the image object 
		ixf.obj = arguments[0];
		
		//copy the image src argument 
		ixf.src = arguments[1];
		
		//store the supported form of opacity
		if(typeof ixf.obj.style.opacity != 'undefined')
		{
			ixf.type = 'w3c';
		}
		else if(typeof ixf.obj.style.MozOpacity != 'undefined')
		{
			ixf.type = 'moz';
		}
		else if(typeof ixf.obj.style.KhtmlOpacity != 'undefined')
		{
			ixf.type = 'khtml';
		}
		else if(typeof ixf.obj.filters == 'object')
		{
			//weed out win/ie5.0 by testing the length of the filters collection (where filters is an object with no data)
			//then weed out mac/ie5 by testing first the existence of the alpha object (to prevent errors in win/ie5.0)
			//then the returned value type, which should be a number, but in mac/ie5 is an empty string
			ixf.type = (ixf.obj.filters.length > 0 && typeof ixf.obj.filters.alpha == 'object' && typeof ixf.obj.filters.alpha.opacity == 'number') ? 'ie' : 'none';
		}
		else
		{
			ixf.type = 'none';
		}
		
		//change the image alt text if defined
		if(typeof arguments[3] != 'undefined' && arguments[3] != '')
		{
			ixf.obj.alt = arguments[3];
		}
		
		//if any kind of opacity is supported
		if(ixf.type != 'none')
		{
			//create a new image object and append it to body
			//detecting support for namespaced element creation, in case we're in the XML DOM
			ixf.newimg = ixf.hcontainer.appendChild((typeof document.createElementNS != 'undefined') ? document.createElementNS('http://www.w3.org/1999/xhtml', 'img') : document.createElement('img'));

			//set positioning classname
			ixf.newimg.className = 'idupe';
			
			//set src to new image src
			ixf.newimg.src = ixf.src

			ixf.direction = Math.floor(Math.random()*4);
			
			
			switch(ixf.direction)
			{
				case 0:
					ixf.directionx = -1;
					ixf.directiony = -1;
					break
				case 1:
					ixf.directionx = 1;
					ixf.directiony = -1;
					break
				case 2:
					ixf.directionx = 1;
					ixf.directiony = 1;
					break
				case 3:
					ixf.directionx = -1;
					ixf.directiony = 1;
					break
			}

			//move it to superimpose original image
			//ixf.newimg.style.left = -100 * ixf.directionx + "px";
			//ixf.newimg.style.top = -100 * ixf.directiony + "px";
			ixf.newimg.style.left = "0px";
			ixf.newimg.style.top = "0px";	
			/*if(ixf.directionx > 0){
				if(ixf.directiony >0){
					ixf.newimg.style.left = "0px";
					ixf.newimg.style.top = "0px";			
				}else{
					ixf.newimg.style.left = "0px";
					ixf.newimg.style.bottom = "0px";			
				}
			}else{
				if(ixf.directiony >0){
					ixf.newimg.style.right = "0px";
					ixf.newimg.style.top = "0px";
				}else{
					ixf.newimg.style.right = "0px";
					ixf.newimg.style.bottom = "0px";			
				}		
			}*/
			
			//copy and convert fade duration argument 
			ixf.length = parseInt(arguments[2], 10) * 1000;
			
			//create fade resolution argument as 20 steps per transition
			ixf.resolution = parseInt(arguments[2], 10) * 20;
			
			//start the timer
			//ixf.newimg.jQuery.effect("scale", { percent: 200 }, 1000);
			ixf.clock = setInterval('ixf.crossfade()', ixf.length/ixf.resolution);
		}
		
		//otherwise if opacity is not supported
		else
		{
			//just do the image swap
			ixf.obj.src = ixf.src;
		}
		
	}
};


//crossfade timer function
ixf.crossfade = function()
{
	//decrease the counter on a linear scale
	ixf.count -= (1 / ixf.resolution);
	ixf.movecount +=0.5;
	
	//if the counter has reached the bottom
	if(ixf.movecount > 30)
	{
		//clear the timer
		clearInterval(ixf.clock);
		ixf.clock = null;
		
		//reset the counter
		ixf.count = 1;
		ixf.movecount = 1;
		
		//set the original image to the src of the new image
		ixf.obj.src = ixf.src;
		
		ixf.obj.style.left = "0px";
		ixf.obj.style.top = "0px";
		//jQuery('#vctagid').effect("scale", { percent: 80 }, 1000); 
			/*if(ixf.directionx > 0){
				if(ixf.directiony >0){
					ixf.obj.style.left = "0";
					ixf.obj.style.top = "0";
					ixf.obj.style.right = "";
					ixf.obj.style.bottom = "";
				}else{
					ixf.obj.style.left = "0";
					ixf.obj.style.bottom = "0";
					ixf.obj.style.right = "";
					ixf.obj.style.top = "";
				}
			}else{
				if(ixf.directiony >0){
					ixf.obj.style.right = "0";
					ixf.obj.style.top = "0";
					ixf.obj.style.left = "";
					ixf.obj.style.bottom = "";
				}else{
					ixf.obj.style.right = "0";
					ixf.obj.style.bottom = "0";	
					ixf.obj.style.top = "";
					ixf.obj.style.left = "";
				}		
			}*/
		
		ixf.obj.opacity = 1;
		
		ixf.obj.width = ixf.newimg.width;
		ixf.obj.height = ixf.newimg.height;
		
		//remove the duplicate image
		ixf.newimg.parentNode.removeChild(ixf.newimg);
		
	}else{
	
		//set new opacity value on both elements
		//using whatever method is supported
		
		opacitycounter = 11-ixf.movecount;
		
		switch(ixf.type)
		{
			case 'ie' :
				//ixf.obj.filters.alpha.opacity = opacitycounter * 10;
				ixf.newimg.filters.alpha.opacity = (10 - opacitycounter) * 10;
				break;
				
			case 'khtml' :
				//ixf.obj.style.KhtmlOpacity = ixf.count;
				ixf.newimg.style.KhtmlOpacity = (1 - ixf.count);
				break;
				
			case 'moz' : 
				//restrict max opacity to prevent a visual popping effect in firefox
				//ixf.obj.style.MozOpacity = (ixf.movecount/10 > 1.1 ? 0.9999999 : ixf.movecount/10);
				ixf.newimg.style.MozOpacity = (1 - opacitycounter/10);
				
				break;
				
			default : 
				//restrict max opacity to prevent a visual popping effect in firefox
				//ixf.obj.style.opacity = ( opacitycounter/10 > 1.1 ? 0.9999999 :  opacitycounter/10);
				ixf.newimg.style.opacity = (0.9 - opacitycounter/10);
		}
		
		//now that we've gone through one fade iteration 
		//we can show the image that's fading in
		ixf.newimg.style.visibility = 'visible';
		
		step_scale = 0.3;
		speedfactor = 1;
		//keep new image in position with original image
		//in case text size changes mid transition or something
		//ixf.newimg.width = parseFloat(ixf.newimg.width) - ((31-ixf.movecount) * step_scale);

		/*}else{
			if(ixf.directionx > 0){
				if(ixf.directiony > 0){
					ixf.newimg.style.left = parseFloat(ixf.newimg.style.left) + (11-ixf.movecount) + "px";
					ixf.newimg.style.top = parseFloat(ixf.newimg.style.top) + (11-ixf.movecount) + "px";			
				}else{
					ixf.newimg.style.left = parseFloat(ixf.newimg.style.left) + (11-ixf.movecount) + "px";
					ixf.newimg.style.bottom = parseFloat(ixf.newimg.style.bottom) + (11-ixf.movecount) + "px";			
				}
			}else{
				if(ixf.directiony > 0){
					ixf.newimg.style.right = parseFloat(ixf.newimg.style.right) + (11-ixf.movecount) + "px";
					ixf.newimg.style.top = parseFloat(ixf.newimg.style.top) + (11-ixf.movecount) + "px";
				}else{
					ixf.newimg.style.right = parseFloat(ixf.newimg.style.right) + (11-ixf.movecount) + "px";
					ixf.newimg.style.bottom = parseFloat(ixf.newimg.style.bottom) +(11-ixf.movecount) + "px";			
				}		
			}
		}*/
		
		//ixf.newimg.style.left = parseFloat(ixf.newimg.style.left) + ixf.directionx*((11-ixf.movecount)) + "px";
		//ixf.newimg.style.top = parseFloat(ixf.newimg.style.top) + ixf.directiony*((11-ixf.movecount)) + "px";			
		
		//ixf.newimg.height = parseFloat(ixf.newimg.height) - (11-ixf.movecount) + "px";
	
	}
};

//get real position method
ixf.getRealPosition = function()
{
	this.pos = (arguments[1] == 'x') ? arguments[0].offsetLeft : arguments[0].offsetTop;
	this.tmp = arguments[0].offsetParent;
	while(this.tmp != null)
	{
		this.pos += (arguments[1] == 'x') ? this.tmp.offsetLeft : this.tmp.offsetTop;
		this.tmp = this.tmp.offsetParent;
	}
	
	return this.pos;
};