var itemsOpen = false;

Event.observe(window, 'load', function() {
	
	var expand_links = $('content').getElementsByClassName('expand_link');
	
	$A(expand_links).each( function(el) {
		el.onclick = function() {
			expandOrCloseItem(el);
			return false;			
		}		
	});
	
	// expand all button
	
	if ($('expand_all')) {
		$('expand_all').onclick = function() {
			var expand_links = $('content').getElementsByClassName('expand_link');
			$A(expand_links).each( function(el) {
				expandOrCloseItem(el);
			});
			
			// change the link text
			if (!itemsOpen) { var link_text = "Expand All Months"; }
			else { var link_text = "Collapse Months"; }
			$('expand_all').innerHTML = link_text;
			
			return false;
		}
	}
});


function expandOrCloseItem(el) {

	var trigger_id = el.getAttribute('id');
	var div_id = trigger_id.replace("trigger_", "");
	
	if ($(div_id)) {
		if ($(div_id).offsetHeight > 0) {
			$(div_id).style.display = "none";
			el.style.backgroundPosition = "0 0";
			itemsOpen = false;
		}
		else {
			$(div_id).style.display = "block";
			el.style.backgroundPosition = "-10px 0";
			itemsOpen = true;
		}
	}
	
}