//cookie functions detailed at http://www.quirksmode.org/js/cookies.html

function createCookie(name,value,days) {
	if (days) {
		var date = new Date();
		date.setTime(date.getTime()+(days*24*60*60*1000));
		var expires = "; expires="+date.toGMTString();
	}
	else var expires = "";
	document.cookie = name+"="+value+expires+"; path=/";
}

function readCookie(name) {
	var nameEQ = name + "=";
	var ca = document.cookie.split(';');
	for(var i=0;i < ca.length;i++) {
		var c = ca[i];
		while (c.charAt(0)==' ') c = c.substring(1,c.length);
		if (c.indexOf(nameEQ) == 0) return c.substring(nameEQ.length,c.length);
	}
	return null;
}

function eraseCookie(name) {
	createCookie(name,"",-1);
}

function close_all(name_prefix, how_many) {
	for (i=1; i<=how_many; i++) {
		var element = name_prefix + i;
		if(document.getElementById(element)) {
			document.getElementById(element).style.display = 'none';
		}
	}
}

function toggle(id){
	var toggleElement = document.getElementById(id);
	if (toggleElement){
		if (toggleElement.style.display == 'none'){
			toggleElement.style.display = '';
			createCookie('last_opened',id);
		} else {
			toggleElement.style.display = 'none';
			eraseCookie('last_opened');
		}
	}
}

function set_last_opened() {
	var open = readCookie('last_opened');
	if(document.getElementById(open)) {
		document.getElementById(open).style.display = '';
	}
	
}