var $		= function(id) { return document.getElementById(id); }
	var $F		= function(obj, index, id) {
		return obj[index].getElementsByTagName(id)[0].firstChild.nodeValue;
	}
	var $ANCHOR	= function(text, url, target) {
		var anchor		= document.createElement("a");
		anchor.href		= url;
//		anchor.target	= (target) ? target : "_blank";
		anchor.appendChild(document.createTextNode(text));
		anchor.style.zIndex	= 100;

		return anchor;
	}

	function hideMonthlyMenu() {
		var monthlyDiv	= $('monthly_div');
		monthlyDiv.style.display	= 'none';
	}

	function switchMonthlyMenu(url) {
		var monthlyDiv	= $('monthly_div');
		if (monthlyDiv) {
			monthlyDiv.style.display	= 'block';
		} else {
			_setMonthlyMenuToDiv(url);
		}
	}

	function _setMonthlyMenuToDiv(url) {
		var request	= _createHttpRequest();
		request.open("GET", url , true);
		request.setRequestHeader("Content-type", "text/xml");

		request.onreadystatechange = function() {
			if (request.readyState==4) {
				var xml	= request.responseXML;
				_makeHTML(xml);
			}
		}

		request.send('');
	}

	function _createHttpRequest() {
		if (window.ActiveXObject) {
			try {
				return new ActiveXObject("Msxml2.XMLHTTP");
			} catch (e) {
				try {
					return new ActiveXObject("Microsoft.XMLHTTP");
				} catch (e2) {
					return null;
	 			}
		 	}
		} else if(window.XMLHttpRequest){
			return new XMLHttpRequest();
		} else {
			return null;
		}
	}

	function _makeHTML(xml) {
		var date;
		var title;
		var url;
		var li;
		var items	= xml.getElementsByTagName("item");
		var ul		= document.createElement('ul');

		for (var i = 0; i < items.length; i++) {
			title	= $F(items, i, "title");
			title	= title.replace(/\t/g, "");
			url		= $F(items, i, "link");

			li		= document.createElement('li');
			li.appendChild($ANCHOR(title, url));
			li.id	= 'monthly_li' + i;
			ul.appendChild(li);
		}

		var div		= document.createElement('div');
		div.id		= 'monthly_div';
		div.appendChild(ul);
		$('monthly_link').appendChild(div);
	}