// -- ajax
var http_request = false;

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

function makePOSTRequest(url, parameters, fun, as) {
   http_request = false;
   if (window.XMLHttpRequest) { // Mozilla, Safari,...
      http_request = new XMLHttpRequest();
      if (http_request.overrideMimeType) {
      	// set type accordingly to anticipated content type
         //http_request.overrideMimeType('text/xml');
         http_request.overrideMimeType('text/xml');
      }
   } else if (window.ActiveXObject) { // IE
      try {
         http_request = new ActiveXObject("Msxml2.XMLHTTP");
      } catch (e) {
         try {
            http_request = new ActiveXObject("Microsoft.XMLHTTP");
         } catch (e) {}
      }
   }
   if (!http_request) {
      alert('Cannot create XMLHTTP instance');
      return false;
   }
   
   http_request.onreadystatechange = fun;
   http_request.open('POST', url, as);
   http_request.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
   http_request.setRequestHeader("Content-length", parameters.length);
   http_request.setRequestHeader("Connection", "close");
   http_request.send(parameters);
}

function cartcheck(){
	if (http_request.readyState == 4) {
      if (http_request.status == 200) {
      	var textDoc = http_request.responseText;
      	//alert(textDoc);
      	if (textDoc == 'FULL'){
      		alert('Uwaga! Możesz zaznaczyć do 100 ośrodków.'); 
      	}
      }
   }
}

function cart(zapid){
	var params = '';
	if (zapid.checked == true){
		params = 'option=add&id='+zapid.value;
	} else {
		params = 'option=del&id='+zapid.value;
	}
	makePOSTRequest('cart.php', params, cartcheck, true);
}

function cartz(zapid){
	var params = '';
	params = 'option=add&id='+zapid;
	makePOSTRequest('cart.php', params, cartcheck, false);
}

function cartd(zapid){
	var params = '';
	params = 'option=del&id='+zapid;
	makePOSTRequest('cart.php', params, cartcheck, false);
}

function cartclear(){
	params = 'option=clr&id=0';
	makePOSTRequest('cart.php', params, cartcheck, false);
}