function createRequestObject() {
    var ro;
    var browser = navigator.appName;
    if(browser == "Microsoft Internet Explorer"){
        ro = new ActiveXObject("Microsoft.XMLHTTP");
    }else{
        ro = new XMLHttpRequest();
    }
    return ro;
}

var http = createRequestObject();

function onShowAdvanced(form,show) {


    http.open('get', 'rpc.php?action=showAdvanced&show='+show);
    http.onreadystatechange = handleResponse;
    http.send(null);

}

function onCategoryChanged(form) {
    var category=form.ufilter_category.options[form.ufilter_category.options.selectedIndex].value;
    if(category == '29')
    	window.location='rvindex.php';

    http.open('get', 'rpc.php?action=updateMakes&ufilter_category='+category);
    http.onreadystatechange = handleResponse;
    http.send(null);

}
function onMakeChanged(form) {

    var category=form.ufilter_category.options[form.ufilter_category.options.selectedIndex].value;
	var make=form.ufilter_make.options[form.ufilter_make.options.selectedIndex].value;
    http.open('get', 'rpc.php?action=updateModels&ufilter_category='+category +'&ufilter_make='+make);
    http.onreadystatechange = handleResponse;
    http.send(null);
}
function handleResponse() {


    if(http.readyState == 4){
        var response = http.responseText;
        var update = new Array();



        if(response.indexOf('|' != -1)) {
            update = response.split('|');
            document.getElementById(update[0]).innerHTML = update[1];

            if(update[0] == 'make') {
               var form = document.getElementById('qsform');
               var category=form.ufilter_category.options[form.ufilter_category.options.selectedIndex].value;

               if(category == 25 || category == 26 || category == 29  || category == 30 || category == 31 || category == 32){
                    document.getElementById('model').innerHTML ="<input name=ufilter_model style='width:120px'>";
               }
               else{
                   document.getElementById('model').innerHTML = "<select disabled style='width:120px'><option>Any model</select>";
               }
            }

        }
    }
}