var currentBannerPosition = 0;
var numberOfBanners = 4;
var timeout;

$(document).ready(function(){
	for (var i = 1; i <= numberOfBanners; i++) {
		$('#banner'+i+'link').css('opacity', '0.5');
	}
	
	changeBanner(0, 0);
});

function changeBanner(id, userInteraction){
	clearTimeout(timeout);
	if (id != currentBannerPosition){
		$('#innerBannerWrapper').stop();
		$('#innerBannerWrapper').animate({marginLeft: (-id*900)+'px'}, 2000);
	}
	
	for (var i = 0; i < numberOfBanners; i++) {
		if (i == id){
			$('#banner'+(i+1)+'link').animate({'opacity': 0.9}, 1000);
		} else {
			$('#banner'+(i+1)+'link').animate({'opacity': 0.5}, 1000);
		}
	}
	
	currentBannerPosition = id;
	var newBannerPosition = (currentBannerPosition == numberOfBanners-1? 0: currentBannerPosition+1);
	if (userInteraction == 1){
		timeout = setTimeout('changeBanner('+newBannerPosition+', 0);', 20000);
	} else {
		timeout = setTimeout('changeBanner('+newBannerPosition+', 0);', 10000);
	}
}