var reqNav = null;
var reqNav1 = null;
var reqList = null;
function newXMLHttpRequest() {
	var xmlreq;
  	// Create XMLHttpRequest object in non-Microsoft browsers
	if (window.XMLHttpRequest) {
		xmlreq = new XMLHttpRequest();
	} else {
		if (window.ActiveXObject) {
			try {
      	// Try to create XMLHttpRequest in later versions
      	// of Internet Explorer
				xmlreq = new ActiveXObject("Msxml2.XMLHTTP");
			}
			catch (e1) {
      	// Failed to create required ActiveXObject 
				try {
        // Try version supported by older versions
        // of Internet Explorer     
					xmlreq = new ActiveXObject("Microsoft.XMLHTTP");
				}
				catch (e2) {
        	// Unable to create an XMLHttpRequest by any means
					xmlreq = false;
				}
			}
		}
	}
	return xmlreq;
}
/*
	* Returns a function that waits for the specified XMLHttpRequest
	* to complete, then passes it XML response to the given handler function.
  * req - The XMLHttpRequest whose state is changing
  * responseXmlHandler - Function to pass the XML response to
  */
function getReadyStateHandler(req, responseXmlHandler) {

   // Return an anonymous function that listens to the XMLHttpRequest instance
	return function () {

     	// If the request's status is "complete"
		if (req.readyState == 4) {
       
       	// Check that we received a successful response from the server
			if (req.status == 200) {
         	// Pass the XML payload of the response to the handler function.
				responseXmlHandler(req.responseXML);
			} else {
         	// An HTTP problem has occurred
				alert("HTTP error " + req.status + ": " + req.statusText);
			}
		}
	};
}
function showNavandList(navid) {
	showNav(navid);
	showList(navid);
}
function showList(navid) {
	reqList = newXMLHttpRequest();
	reqList.onreadystatechange = getReadyStateHandler(reqList, updateList);
	reqList.open("POST", "index.do", true);
	reqList.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
	reqList.send("action=showList&navid=" + navid);
}
function showNav(navid) {
	reqNav = newXMLHttpRequest();
	reqNav.onreadystatechange = getReadyStateHandler(reqNav, updateNav);
	reqNav.open("POST", "index.do", true);
	reqNav.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
	reqNav.send("action=showNav&navid=" + navid);
}
function updateNav() {
	var itemMenu = document.getElementById("menu");
	itemMenu.innerHTML = "";
	var ulElement = document.createElement("UL");
	ulElement.innerHTML = reqNav.responseText;
	itemMenu.appendChild(ulElement);
}
function updateList() {
	var body = document.getElementById("body");
	body.innerHTML = "";
	body.innerHTML = reqList.responseText;
}
function showHide(id) {
	showList(id);
	var el = document.getElementById(id);
	var bExpand = true;
	var aTag = el.getElementsByTagName("A");
	if (aTag[0].name == "-") {
		bExpand = false;
		aTag[0].setAttribute("name", "+");
	} else {
		bExpand = true;
		aTag[0].setAttribute("name", "-");
	}
	var subs = el.lastChild;
	if (bExpand) {
		subs.style.display = "block";
	} else {
		subs.style.display = "none";
	}
}
var gid = null;
function getSubTree(navid) {
	showList(navid);
	gid = navid;
	reqNav = newXMLHttpRequest();
	reqNav.onreadystatechange = getReadyStateHandler(reqNav, parseSubTree);
	reqNav.open("POST", "index.do", true);
	reqNav.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
	reqNav.send("action=showNav&navid=" + navid);
}
function parseSubTree() {
	var el = document.getElementById(gid);
	var ulElmt = document.createElement("UL");
	ulElmt.innerHTML = reqNav.responseText;
	el.appendChild(ulElmt);
	var aTag = el.getElementsByTagName("A");
	aTag[0].setAttribute("name", "-");
	aTag[0].setAttribute("onclick", new Function("showHide('" + gid + "')"));
}