var http_request = false;
var thetarget;
var response = false;

function loadXMLDoc(url, parameters) {
 try {
    netscape.security.PrivilegeManager.enablePrivilege("UniversalBrowserRead");
   } catch (e) {
    
   }

    http_request = false;
    if(window.XMLHttpRequest && !(window.ActiveXObject)) {
    	try {
			http_request = new XMLHttpRequest();
        } catch(e) {
			http_request = false;
        }
    // branch for IE/Windows ActiveX productlist
    } else if(window.ActiveXObject) {
       	try {
        	http_request = new ActiveXObject("Msxml2.XMLHTTP");
      	} catch(e) {
        	try {
          		http_request = new ActiveXObject("Microsoft.XMLHTTP");
        	} catch(e) {
          		http_request = false;
        	}
		}
    }
    if (http_request.overrideMimeType) {
      http_request.overrideMimeType('text/xml');
    }
    if (!http_request) {
      alert('Cannot create XMLHTTP instance');
      return false;
    }
    http_request.onreadystatechange = processReqChange;
    http_request.open('GET', url + parameters, true);
    http_request.send(null);
}

function processReqChange() {
   if (http_request.readyState == 4) {
	   	document.getElementById('classrules').innerHTML='';
		response = http_request.responseText;		
    	targetarea = document.getElementById(thetarget);
		targetarea.innerHTML=response;
	} 
}

function getclasses(){	
	thetype = document.getElementById('racetype').value;
	thetarget = 'racingclasses';
	stamp = Math.floor(Math.random()*100);
	theurl = thisurl+'ajax/rules.php?action=classes&type='+thetype+'&stamp='+stamp;
	document.getElementById(thetarget).innerHTML='<select name="raceclass" id="raceclass"><option value="">--Loading--</option></select>';
	document.getElementById('classrules').innerHTML = '<center><img src="http://www.mobilercracing.com/images/loading_ajax.gif"></center>';	
	if(thetype != ''){
		loadXMLDoc(theurl); 	
	}
	else{
		document.getElementById(thetarget).innerHTML='<select name="raceclass" id="raceclass"><option value="">--Please select a racing type first--</option></select>';
	}
}

function getrules(){
	document.getElementById('classrules').innerHTML = '<center><img src="http://www.mobilercracing.com/images/loading_ajax.gif"></center>';
	thetarget = 'classrules';
	//document.getElementById(thetarget).innerHTML='';
	theclass = document.getElementById('raceclass').value;
	stamp = Math.floor(Math.random()*100);
	theurl = thisurl+'ajax/rules.php?action=rules&class='+theclass+'&stamp='+stamp;
	if(theclass != ''){
		loadXMLDoc(theurl);
	}
}