/**
 * Image roll over object
 * Revision 1.1	15/09/08 - Fixed Preload bug
 */
ro={
	//The following constants give the class to use in the html and 
	//the image postfix to add for the rolled state
	rollClass: 'wh-roll',
	overSrcAddOn: '_on',
	//No need to change below
	preloads: [],
	init: function(){
		var oversrc;
		var imgs = document.images;
		for (var i=0;i<imgs.length;i++){
			if(!WH.cssjs('check',imgs[i],ro.rollClass)){
				continue;
			}
			oversrc = ro.addExt(imgs[i].src);
			ro.preloads[i]=new Image();
			ro.preloads[i].src = oversrc;
			WH.addEvent(imgs[i],'mouseover',ro.roll,false);
			WH.addEvent(imgs[i],'mouseout',ro.roll,false);
		}
	},
	roll: function(e){
		var t = WH.getTarget(e);
		var s = t.src;
		if (e.type =='mouseover'){
			t.src = ro.addExt(s);
		}
		if (e.type =='mouseout'){
			t.src = ro.remExt(s);
		}
	},
	addExt:function(a){
		lastdot = a.lastIndexOf(".");
		if (lastdot==-1){
			return a;
		} else {
			var ext = a.slice(lastdot,a.length);
			return a.slice(0,lastdot) + ro.overSrcAddOn + ext;
		}
		
	},
	remExt:function(a){
		lastdot = a.lastIndexOf(ro.overSrcAddOn + '.');
		if (lastdot==-1){
			return a;
		} else {
			var ext = a.slice(lastdot+ro.overSrcAddOn.length,a.length);
			return a.slice(0,lastdot) + ext;
		}		
	}
}
WH.addEvent(window,'load',ro.init,false);