/* JS */

(function () {

	// run init() when page loads
	if (window.addEventListener) {
		window.addEventListener('load', init, false);
	} else if (window.attachEvent) {
		window.attachEvent('onload', init);
	}
	
	function init() {
		// when page loads:
		
		var imageelements = document.getElementsByTagName('img');
		
		var classRegExp = /(^|\s)rollover(\s|$)/;
		
		for (var i=0; i < imageelements.length; i++) {
			
			if (classRegExp.test(imageelements[i].className)) {
				// add rollover events
				imageelements[i].onmouseover = function () {
					var s = this.src;
					var extension = s.substring(s.length-4);
					var firstpart = s.substring(0,s.length-4);
					this.src = firstpart + "_rollover" + extension;
				}
				imageelements[i].onmouseout = function () {
					var s = this.src;
					var extension = s.substring(s.length-4);
					var firstpart = s.substring(0,s.length-13);
					this.src = firstpart + extension;
				}
				var s = imageelements[i].src;
				var extension = s.substring(s.length-4);
				var firstpart = s.substring(0,s.length-4);
				
				// preload the image
				(new Image()).src = firstpart + "_rollover" + extension;
				
			}
		}
		
	}
	
}) ();