var receiveReq = getXmlHttpRequestObject();
var receiveReq1 = getXmlHttpRequestObject();
function getXmlHttpRequestObject(){
  if (window.XMLHttpRequest){
    return new XMLHttpRequest();
  }else if(window.ActiveXObject){
    return new ActiveXObject("Microsoft.XMLHTTP");
  }
}

function getStreets(area_id,street_id){
	document.getElementById('street_id').options.length=0;
	document.getElementById('street_id').options[0]=new Option('Загрузка...','0');
  receiveReq.open("GET",'/streets.php?area_id='+area_id+'&street_id='+street_id, true);
  receiveReq.onreadystatechange = handleReceiveGetStreets;
  receiveReq.send(null);
}

function handleReceiveGetStreets(){
	if (receiveReq.readyState==4){
		var response = eval('(' + receiveReq.responseText + ')');
		for(var i=0;i<response.streets.length;i++){
			document.getElementById('street_id').options[i]=new Option(response.streets[i].title,response.streets[i].area_id);
			if(response.streets[i].selected!='') document.getElementById('street_id').options[i].selected=true;
		}
		if(!response.streets.length) document.getElementById('street_id').options[i]=new Option('-- не задано --',0);
	}
}

function getTypeCategories(type_id,tc_id){
	document.getElementById('tc_id').options.length=0;
	document.getElementById('tc_id').options[0]=new Option('Загрузка...','0');
  receiveReq1.open("GET",'/tc.php?type_id='+type_id+'&tc_id='+tc_id, true);
  receiveReq1.onreadystatechange = handleReceiveGetTypeCategories;
  receiveReq1.send(null);
}

function handleReceiveGetTypeCategories(){
	if (receiveReq1.readyState==4){
		var response = eval('(' + receiveReq1.responseText + ')');
		for(var i=0;i<response.categories.length;i++){
			document.getElementById('tc_id').options[i]=new Option(response.categories[i].title,response.categories[i].id);
			if(response.categories[i].selected!='') document.getElementById('tc_id').options[i].selected=true;
		}
		if(!response.categories.length) document.getElementById('tc_id').options[i]=new Option('-- все типы --',0);
	}
}