var cur_page = 0;

window.addEvent('domready', function(){
	
	$$('.arrow_right').addEvent('click',function() {
		pageForward();
	});
	
	$$('.image_link').addEvent('click',function() {
		pageForward();
	});
	
	$$('.arrow_left').addEvent('click',function() {
		pageBack();
	});
	
	staticNav();
});

window.addEvent('resize', function(){
	staticNav();
});

function staticNav() { 
	var sidenavHeight = $("sidenav").height();
	var winHeight = window.getSize().y
	var browserIE6 = (navigator.userAgent.indexOf("MSIE 6")>=0) ? true : false;

	if (browserIE6) {
		$("sidenav").setStyle('position','absolute');
	} else {
		$("sidenav").setStyle('position','fixed');
	}

	if (sidenavHeight > winHeight) {
		$("sidenav").setStyle('position','static');
	}
}

function pageForward() {
	$$('.image')[cur_page].addClass('hidden');
	cur_page = cur_page == $$('.image').length-1 ? $$('.image').length-1 : cur_page + 1;
	$$('.image')[cur_page].removeClass('hidden');
	var el = $$('.image')[cur_page].getFirst();
	if(el.get('source')) {
		el.src = el.get('source');
	}
	$('page_count').innerHTML = cur_page+1;
}

function pageBack() {
	$$('.image')[cur_page].addClass('hidden');
	cur_page = cur_page == 0 ? 0 : cur_page - 1;
	$$('.image')[cur_page].removeClass('hidden');
	var el = $$('.image')[cur_page].getFirst();
	if(el.get('source')) {
		el.src = el.get('source');
	}
	$('page_count').innerHTML = cur_page+1;
}