var fb_link_request = false;

function facebook_onlogin() {
    makeFacebookLinkRequest("http://www.zoomatlas.com/mediawiki/skins/za_skin/FacebookLink.php", "");
}

function makeFacebookLinkRequest(url, parameters) {
    fb_link_request = false;
    if (window.XMLHttpRequest) { // Mozilla, Safari,...
	fb_link_request = new XMLHttpRequest();
	if (fb_link_request.overrideMimeType) {
	    fb_link_request.overrideMimeType('text/html');
	}
    } else if (window.ActiveXObject) { // IE
	try {
	    fb_link_request = new ActiveXObject("Msxml2.XMLHTTP");
	} catch (e) {
	    try {
		fb_link_request = new ActiveXObject("Microsoft.XMLHTTP");
	    } catch (e) {}
	}
    }
    if (!fb_link_request) {
	alert('Cannot create XMLHTTP instance');
	return false;
    }
    
    fb_link_request.onreadystatechange = fbLinkResponse;
    
    fb_link_request.open('POST', noCache(url), true);
    fb_link_request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
    fb_link_request.setRequestHeader("Content-length", parameters.length);
    fb_link_request.setRequestHeader("Connection", "close");
    fb_link_request.send(parameters);
}

function fbLinkResponse() {
    if (fb_link_request.readyState == 4) {
	if (fb_link_request.status == 200) {
	    result = fb_link_request.responseText;
	    if (result == "REFRESH") {
	        refresh_page();
	    }
	}
    }
}

function refresh_page() {
  window.location.reload();
}