var Dom = YAHOO.util.Dom;
var Anim = YAHOO.util.Anim;
var Event = YAHOO.util.Event;
	

	
	var newClass = '';
	var animationTween = false;
	
	function changeBackground(e, newClassName){
		
		newClass = newClassName;
		
		var bgLayer1 = Dom.get('hpLayer1');
		var bgLayer2 = Dom.get('hpLayer2');
		
		var oldClass = bgLayer2.className;
		
		if (animationTween === false && newClass!=oldClass){
		
		
			Dom.replaceClass(bgLayer1, bgLayer1.className, newClass);
				
			var attributes = {
				opacity : {
					 to : 0.0
				}
			}
		
			var animation = new Anim(bgLayer2,attributes,0.5,YAHOO.util.Easing.easeOut);
				
			animation.onStart.subscribe(
											function(){
												animationTween = true;
	
											}
										 ); 
		
			animation.onComplete.subscribe(
											function(){
												

												Dom.replaceClass(Dom.get('hpLayer2'), Dom.get('hpLayer2').className, Dom.get('hpLayer1').className);
												Dom.setStyle(Dom.get('hpLayer2'), 'opacity', 1.0);
												animationTween = false;
												
												/*
												alert(Dom.get('hpLayer1').getAttribute('class'));
												alert(newClass);
												*/
												
												if (Dom.get('hpLayer1').className != newClass) {

													changeBackground(null, newClass);
												}
										   }
										  );
			animation.animate();
		}
	}



	function homepagePicsInit() {
		var hpLinks = Dom.getElementsByClassName('homepagelink');
		for (var i = 0; i<hpLinks.length; i++) {
			var hpLink = hpLinks[i];
			Event.addListener(hpLink, 'mouseover', changeBackground, hpLink.name);
		}
		

		//preload background
      preload_image_object = new Image();
      // set image url
      image_url = new Array();
      image_url[0] = "/images/layout/homepage/barevna_geometrie.jpg";
      image_url[1] = "/images/layout/homepage/dokonaly_styl.jpg";
      image_url[2] = "/images/layout/homepage/drevo_i_kov.jpg";
      image_url[3] = "/images/layout/homepage/harmonie_odstinu.jpg";
	  image_url[4] = "/images/layout/homepage/hra_barev.jpg";
	  image_url[5] = "/images/layout/homepage/jednoducha_elegance.jpg";

       var i = 0;
       for(i=0; i<=5; i++) {
         preload_image_object.src = image_url[i];
    	}

  
		
		
	}
	
	Event.onDOMReady(homepagePicsInit);