nn4 = (document.layers)? true : false;
ie4 = (document.all)? true : false;
nn6 = (document.getElementById && !ie4)? true : false;

function popupWin(fileName, windowName, winWidth, winHeight) {
	if (nn4 || ie4 || nn6) {
		posX = Math.round ((screen.width - winWidth) / 2);
		posY = Math.round ((screen.height - winHeight) / 2 - window.opera ? 80 : 35);
		posCode = (nn4 || nn6)? "screenX="+posX+",screenY="+posY : "left="+posX+",top="+posY;
	} else {
		posCode = "";
	}
	newWindow = window.open(fileName,windowName,'menubar=no,toolbar=no,scrollbars=yes,status=yes,width='+winWidth+',height='+winHeight+','+posCode);
	newWindow.focus();
}


var keep = false;
function ToggleLoginPanel() {
	var LoginPanel = document.getElementById ('auth_form');
	if (LoginPanel) {
		var display = LoginPanel.style.display;
		if (display == 'none' || !display) {
			LoginPanel.style.display = 'block';
			var LoginInput = document.getElementById ('Username');
			if (LoginInput) LoginInput.focus();
			
			keep = true;
			document.onclick = CloseLoginPanel;
			document.onkeydown = EscapeLoginPanel;
			var UsernameField = document.getElementById ('Username');
			var PasswordField = document.getElementById ('Password');
			var SessionSubmit = document.getElementById ('SessionSubmit');
			var SessionRemember = document.getElementById ('SessionRemember');
			if (UsernameField) UsernameField.onclick = Keep;
			if (PasswordField) PasswordField.onclick = Keep;
			if (SessionSubmit) SessionSubmit.onclick = Keep;
			if (SessionRemember) SessionRemember.onclick = Keep;
			TestLogin();
		}
		else {
			LoginPanel.style.display = 'none';
		}
		return false;
	}
	else return true;
}

function Keep() {
	keep = true;
}

function CloseLoginPanel (event) {
	if (keep) {
		keep = false;
		return;
	}
	var LoginPanel = document.getElementById ('auth_form');
	if (!LoginPanel) return;
	LoginPanel.style.display = 'none';

	document.onclick = null;
	document.onkeydown = null;
}

function EscapeLoginPanel (event) {
	if (window.event) event = window.event;
	var code = event.keyCode ? event.keyCode : event.which ? event.which : null;
	if (code == 27) {
		var LoginPanel = document.getElementById ('auth_form');
		if (!LoginPanel) return;
		LoginPanel.style.display = 'none';

		document.onclick = null;
		document.onkeydown = null;
	}
}

function TestLogin() {
	var UsernameField = document.getElementById ('Username');
	var PasswordField = document.getElementById ('Password');
	var SessionSubmit = document.getElementById ('SessionSubmit');
	if (!UsernameField || !PasswordField || !SessionSubmit) return;

	SessionSubmit.disabled = !UsernameField.value || !PasswordField.value; 
}