//SLIDESHOW
function nextSlide(slide) {
	var next_slide;
	switch (slide) {
		case 2:
			next_slide = 1;
			break;
		default:
			next_slide = slide + 1;
	}
	return next_slide;
}

function nextBanner(banner) {
	var next_banner;
	if (banner>=banners_count) 
		next_banner = 0;
	else
		next_banner = banner + 1;
	return next_banner;
}

function loadBanner(id) {

	clearInterval(t);
	t=setInterval("loadBanner()",7000);

	var banner, banner_link;
	
	if (!id) {
		id = nextBanner(current_banner);
	}

	current_slide = nextSlide(current_slide);	
	current_banner = id;

	if (current_slide==1) {
		updateBannerNav(current_banner);
		$("#b1").load("includes/banner_v2_image.asp?img=" + banners[current_banner] + "&lnk=" + links[current_banner], function() {
			$("#b1").fadeIn("slow", function() {
				//preload next image
				preloadBanner(nextBanner(current_banner),nextSlide(current_slide));
			});
		});
	}
	else {
		updateBannerNav(current_banner);	
		$("#b2").show();
		$("#b2").load("includes/banner_v2_image.asp?img=" + banners[current_banner] + "&lnk=" + links[current_banner], function() {
			$("#b1").fadeOut("slow", function() {
				//preload next image
				preloadBanner(nextBanner(current_banner),nextSlide(current_slide));
			});
		});
	}

}

function preloadBanner(id,slide) {
	$("b" + slide).load("includes/banner_v2_image.asp?img=" + banners[id] + "&lnk=" + links[id]);
}

function updateBannerNav(id) {
	$(".banner_nav_circle").css({'background-position-y':'0'});
	$("#banner_nav_" + id).css({'background-position-y':'-8px'});
}

function buildBannerNav() {
	var count, html, i, href, left_margin;
	count = banners_count;
	i=0;
	while (i<=count) {
		href = '<a href="#" onclick="loadBanner(\'' + i + '\');return false;" class="banner_nav_circle" id="banner_nav_' + i + '"></a>';
		if (html) 
			html = html + href;
		else
			html = href;
		i++;
	}
	
	//set margin
	left_margin = parseInt((809-(count * 18))/2);
	$("#banner_nav").css({'margin-left':left_margin + 'px'});
	
	//print nav circles
	$("#banner_nav").html(html);
	
	//set style of first nav circle
	$("#banner_nav_0").css({'background-position-y':'-8px'});	
}