function Navi() {}

Navi.preloadImages = [];

Navi.preloadImage = function(src) {
	var im = new Image();
	im.src = src;
	Navi.preloadImages.push(im);
}

Navi.over = function(obj) {
	var tmp = $(obj).childElements();
	tmp[0].src = tmp[0].src.replace(/\.gif/, '_over.gif');
}

Navi.out = function(obj) {
	var tmp = $(obj).childElements();
	tmp[0].src = tmp[0].src.replace(/_over\.gif/, '.gif');	
}

Navi.go = function(obj) {
	window.location.href = obj.attributes['name'].value;
}

Navi.init = function(url) {
	if (url == undefined) {
		url = window.location.href.substring(window.location.href.lastIndexOf('/')+1);
		if (url == '' || url == 'index.html')
			url = '/';
	}
	
	var tmp = $$('div.naviitem');
	for (var x=0; x<tmp.length; x++) {
		if (tmp[x].attributes['name'].value == url) {
			tmp[x].addClassName('selected');
			var img = tmp[x].childElements()[0];
			img.src = img.src.replace(/\.gif/, '_sel.gif');
		} else {
			tmp[x].onmouseover = function() { Navi.over(this); } 
			tmp[x].onmouseout = function() { Navi.out(this); } 
			tmp[x].onclick = function() { Navi.out(this); Navi.go(this); } 
			var prefix = tmp[x].childElements();
			prefix = prefix[0].src.substring(0, prefix[0].src.length-4);
			Navi.preloadImage(prefix + "_over.gif");
		}
	}
	
}