var MAX_IMAGES = 12;

var TIME_TRANSITION = 5;
var CURRENT_IMAGE = 1;
var TIME_DISPLAY = 5000;
var id = 'swapimage';

window.onload = function() {
	if(window.location.href.indexOf("acatalog")==-1)
		fade();
}

function fade() {
	fadeout();
}

function swapimage() {
	CURRENT_IMAGE = (CURRENT_IMAGE>=MAX_IMAGES)?1:CURRENT_IMAGE+1;
	document.getElementById(id).src ='acatalog/'+ id+'_'+CURRENT_IMAGE+'.jpg';
	fadein();
}

function fadein() {
	setopacity(0);
	for(var i=100; i>=0; i--) {
		setTimeout("setopacity("+(i)+")", (i*TIME_TRANSITION));
	}
	setTimeout("fade()", TIME_DISPLAY);
}

function fadeout() {
	setopacity(100);
	for(var i=0; i<=100; i++) {
		setTimeout("setopacity("+(100-i)+")", (i*TIME_TRANSITION));
	}
	setTimeout("swapimage()", TIME_TRANSITION*100);
}

function setopacity(opacity) {
	var element = document.getElementById(id).style;
	element.opacity=(opacity/99);
	element.MozOpacity=(opacity/100);
	element.KhtmlOpacity=(opacity/100);
	element.filter="alpha(opacity="+opacity+")";
}