// JavaScript Document

var swap_out = new Array();
var swap_over = new Array();

var swap_img_out = new Array();
var swap_img_over = new Array();

var swap_elements = new Array();

var nav;
	
function swapInit() {
	nav = document.getElementById("subnav");
	se1 = document.getElementsByName("btn");
	
	for(var i = 0; i < se1.length; i++)
	{
		swap_elements.push(se1[i]);
	}
	
	se2 = document.getElementsByName("img");
	
	for(var i = 0; i < se1.length; i++)
	{
		swap_elements.push(se2[i]);
	}
		
	for(var i = 0; i < swap_elements.length; i++){
	
		if(swap_elements[i]!=null)
		{
			id = swap_elements[i].id;

			if(id!="leistungen"){
				if(swap_elements[i].name=="btn")
				{
					id = id.replace(/btn/,"img");
				}
				else
				{
					id = id.replace(/img/,"btn");
				}
				
			}	

			var img = document.getElementById(id);

			// preload Out-Image
			swap_out[i] = new Image();
			swap_out[i].src = swap_elements[i].src;
	
			if(img)
			{
				swap_img_out[i] = new Image();
				swap_img_out[i].src = img.src;		
			}
			
			// preload Over-Image
			tmp_src = swap_out[i].src.replace(/_a\./,"_b.");
			swap_over[i] = new Image();
			swap_over[i].src = tmp_src;
			
			if(img)
			{
				tmp_src2 = img.src.replace(/_a\./,"_b.");
				swap_img_over[i] = new Image();
				swap_img_over[i].src = tmp_src2;
			}
			
		// Evenlistener für alle Buttons	
			swap_elements[i].onmouseover = new Function("swapImg("+i+")");
			swap_elements[i].onmouseout = new Function("swapImg("+i+")");
		}
	}
}

function swapImg(i){
	id = swap_elements[i].id;
	
	if(swap_elements[i].name=="btn")
	{
		id = id.replace(/btn/,"img");
	}
	else
	{
		id = id.replace(/img/,"btn");
	}
			
	//id = id.replace(/btn/,"img");
	var img;
	if(swap_elements[i].id=="leistungen")
	{
			

		if(nav.style.visibility!="visible")		
			nav.style.visibility="visible";
		else
			nav.style.visibility="hidden";

	}	
		
		if(id)
		{
			img = document.getElementById(id);
		}
		
	if(swap_elements[i].src == swap_out[i].src)
	{
		swap_elements[i].src = swap_over[i].src;
		if(img && swap_img_over[i])
		{
			img.src = swap_img_over[i].src;			
		}
	}
	else
	{
		swap_elements[i].src = swap_out[i].src;
		if(img && swap_img_out[i])
		{
			img.src = swap_img_out[i].src;		
		}
	}
}