function send_xmlhttprequest(obsluha, method, url, content, headers) {
    var xmlhttp = (window.XMLHttpRequest ? new XMLHttpRequest() : (window.ActiveXObject ? new ActiveXObject("Microsoft.XMLHTTP") : false));

	if (!xmlhttp)
		return false;

	xmlhttp.open(method, url);

	if (obsluha != null)
		xmlhttp.onreadystatechange = function() {
			obsluha(xmlhttp);
		};

	if (headers) {
		for (var key in headers)
			xmlhttp.setRequestHeader(key, headers[key]);
	}

	xmlhttp.send(content);
	return true;
}

function data() {
  var ic = document.getElementById('firmaic').value;
    
	if (!send_xmlhttprequest(data_r, 'GET', '/app/ares-app.php?ic=' + ic)) {
		return true;
	}
	
	document.getElementById('stav').innerHTML = 'Načítám...';
	
	return false;
}

function data_r(xmlhttp) {
    
	if (xmlhttp.readyState == 4) {
    var error = xmlhttp.responseXML.getElementsByTagName('error')[0];
      if(error != null) {
        alert(error.childNodes[0].data);
      }
      else {
        var odpovedi = xmlhttp.responseXML.getElementsByTagName('message')[0].childNodes;
        
        	    for (var i = 0; i < odpovedi.length; i++) {
          			if (odpovedi[i].childNodes.length > 0) {
          				var obj = document.getElementById(odpovedi[i].nodeName);
          				if (obj)  obj.value = odpovedi[i].childNodes[0].data;
          			}
        		}
      }
    document.getElementById('stav').innerHTML = '';
  }
  
}