window.onload = function(){
	navigationEffect = new effectMenu();
	
}

function effectMenu(){
	menu = document.getElementById("navigation-menu");
	menuElements = menu.getElementsByTagName("LI");
	ArrayElements = $A(menuElements);
	
	
	var total = ArrayElements.length;
	for(i=0;i<total;i++){
		if (!hasClass(ArrayElements[i], "current")) {
			ArrayElements[i].onmouseover = function(){
				var span = document.createElement("SPAN");
				var span2 = document.createElement("SPAN");
				span.className = "left";
				span2.className = "right";
				this.appendChild(span);
				this.appendChild(span2);
				this.style.zIndex = "5";
			}
			
			ArrayElements[i].onmouseout = function(){
				$A(this.getElementsByTagName("SPAN")).remove();
				this.removeAttribute("style");
			}
		}
		else{
				var span = document.createElement("SPAN");
				var span2 = document.createElement("SPAN");
				span.className = "left";
				span2.className = "right";
				ArrayElements[i].appendChild(span);
				ArrayElements[i].appendChild(span2);
				ArrayElements[i].style.zIndex = "5";
		}
	}
}

function hasClass(elemento, clase){
	return (elemento.className.indexOf(clase) != -1) ? true : false;
}

Array.prototype.remove = function(){
	var total = this.length;
	for(var i=0;i<total;i++)
		this[i].parentNode.removeChild(this[i]);
}

$A = function(elements){
	response = [];
	for(i=0;i<elements.length;i++)
		response.push(elements[i]);
	return response;
}

addEvent = function(event, element, func){
	if (window.addEventListener) {
		element.addEventListener(event, func, false);
	}
	else if (window.attachEvent) {
		var response = element.attachEvent("on" + event, func);
		return response;
	}
	else
		throw "No es posible lanzar el evento.";
		
}