// JavaScript Document

function highlightTopic() {
	var el = $(this);
	var index = parseInt(el.attr('id').substr(1));
	el.css('background-image', 'url(../images/topic0' + index + 'h.gif)');
}

function preloadTopics() {
	for (var i = 1; i <= 6; i = i+1) {
		$("div#q" + i).css('background-image', 'url(../images/topic0' + i + 'h.gif)');
	}
	for (var i = 1; i <= 6; i = i+1) {
		$("div#q" + i).css('background-image', 'url(../images/topic0' + i + '.gif)');
	}
}

function clearHighlights () {
	for(var i = 1; i < 6; i = i+1) {
		if ($("div#q" + i).hasClass('current') == false)
			$("div#q" + i).css('background-image', 'url(../images/topic0' + i + '.gif)');
	}
}

function selectTopic () {
	var el = $(this);
	var index = parseInt(el.attr('id').substr(1));
	for(var i = 1; i < 6; i = i+1)
		$("div#q" + i).removeClass('current');
	el.addClass('current');
	
	$("[id *= 'ans']").each(function() {
		$(this).css('display', 'none');
		$(this).css('visibility', 'hidden');
	});
	
	$("div#ans" + index).css('display', 'block');
	$("div#ans" + index).css('visibility', 'visible');
}

$(function() {
	$("div.home-topics").mouseover(highlightTopic);
	$("div.home-topics").mouseout(clearHighlights);
	$("div.home-topics").click(selectTopic);
	
	preloadTopics();
		
});