// JScript File
var xmlHttp = createXmlHttpRequestObject();

function checkZbozi()
{
	try
    {
      // initiate reading the async.txt file from the server
      var a_name_school = document.getElementById('a_name_school');
	  var sc = a_name_school.options[a_name_school.selectedIndex].innerText;
	  if (sc==undefined) {
		  sc=a_name_school.options[a_name_school.selectedIndex].value;
	  }
      var url = "http://www.polyglot.cz/js/validate.php?a_name_school="+sc;
      xmlHttp.open("GET", url, true);
      xmlHttp.onreadystatechange = handleServerResponse;
      xmlHttp.send(null);
    }
    // display the error in case of failure
    catch (e)
    {
      alert("Can't connect to server:\n" + e.toString());
      
    }
}

function createXmlHttpRequestObject() {
	var xmlHttp;
	if(window.ActiveXObject)
	{
		try
		{
			xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");		
		}
		catch (e)
		{
			xmlHttp = false;
		}
	
	}
	else
	{
		try
	  	{
		  // try to create XMLHttpRequest object
		  xmlHttp = new XMLHttpRequest();
		}
		catch(e)
		{
		  // assume IE6 or older
		  var XmlHttpVersions = new Array("MSXML2.XMLHTTP.7.0",
		  								  "MSXML2.XMLHTTP.6.0",
		                                  "MSXML2.XMLHTTP.5.0",
		                                  "MSXML2.XMLHTTP.4.0",
		                                  "MSXML2.XMLHTTP.3.0",
		                                  "MSXML2.XMLHTTP",
		                                  "Microsoft.XMLHTTP");
		  // try every prog id until one works
		  for (var i=0; i<XmlHttpVersions.length && !xmlHttp; i++) 
		  {
		    try 
		    { 
		      // try to create XMLHttpRequest object
		      xmlHttp = new ActiveXObject(XmlHttpVersions[i]);
		    } 
		    catch (e) {}
		  }
		}
	}
	
	if(!xmlHttp)
		alert("Error creating the XMLHttpRequest object.")
	else
		return xmlHttp;
}

function handleServerResponse()
{
	if (xmlHttp.readyState == 4)
	{
		if (xmlHttp.status == 200)
		{
			try
			{
				var xmlResponse = xmlHttp.responseXML;
				xmlRoot = xmlResponse.documentElement;
				var a_trida1 = xmlRoot.getElementsByTagName("a_trida1");
				var a_trida2 = xmlRoot.getElementsByTagName("a_trida2");
				var a_trida3 = xmlRoot.getElementsByTagName("a_trida3");
				var a_trida4 = xmlRoot.getElementsByTagName("a_trida4");
				var a_jazyk = xmlRoot.getElementsByTagName("a_jazyk");
				var a_den1 = xmlRoot.getElementsByTagName("a_den1");
				var a_den2 = xmlRoot.getElementsByTagName("a_den2");
				var a_hodina1 = xmlRoot.getElementsByTagName("a_hodina1");
				var a_hodina2 = xmlRoot.getElementsByTagName("a_hodina2");
				var a_ucebna = xmlRoot.getElementsByTagName("a_ucebna");
				var a_cena = xmlRoot.getElementsByTagName("a_cena");
				var a_poznamka = xmlRoot.getElementsByTagName("a_poznamka");
				var a_kurz_zaplnen = xmlRoot.getElementsByTagName("a_kurz_zaplnen");
		
				document.getElementById("a_trida1").options[0] = new Option(a_trida1.item(0).firstChild.data,a_trida1.item(0).firstChild.data);	
				document.getElementById("a_trida1").options[1] = new Option(a_trida2.item(0).firstChild.data,a_trida2.item(0).firstChild.data);
				document.getElementById("a_trida1").options[2] = new Option(a_trida3.item(0).firstChild.data,a_trida3.item(0).firstChild.data);
				document.getElementById("a_trida1").options[3] = new Option(a_trida4.item(0).firstChild.data,a_trida4.item(0).firstChild.data);
				
				for (i=1;i<4;i++) {
					if (document.getElementById("a_trida1").options[i].text == "-") {
						document.getElementById("a_trida1").options[i].style.display = "none";
					}
				}
				
				document.getElementById("a_jazyk").options[0] = new Option(a_jazyk.item(0).firstChild.data,a_jazyk.item(0).firstChild.data);
				document.getElementById("a_den1").innerHTML = a_den1.item(0).firstChild.data;
				document.getElementById("a_den2").innerHTML = a_den2.item(0).firstChild.data;
				document.getElementById("a_hodina1").innerHTML = a_hodina1.item(0).firstChild.data;
				document.getElementById("a_hodina2").innerHTML = a_hodina2.item(0).firstChild.data;
				document.getElementById("a_ucebna").innerHTML = a_ucebna.item(0).firstChild.data;
				document.getElementById("a_cena").innerHTML = a_cena.item(0).firstChild.data;
				document.getElementById("a_poznamka").innerHTML = a_poznamka.item(0).firstChild.data;
				
				if (a_kurz_zaplnen.item(0).firstChild.data=="Ano") {
					
					document.getElementById("a_kurz_zaplnen").style.display='block';
					document.getElementById("a_kurz_zaplnen").style.visibility='visible';
					document.getElementById("a_kurz_zaplnen1").style.display='block';
					document.getElementById("a_kurz_zaplnen1").style.visibility='visible';
					document.getElementById("reg_form").style.display='none';
					document.getElementById("reg_form").style.visibility='hidden';
					
					document.getElementById("a_kurz_zaplnen").innerHTML = '<b>'+a_kurz_zaplnen.item(0).firstChild.data+'</b>';
					
				}
				else {
					document.getElementById("a_kurz_zaplnen").style.display='none';
					document.getElementById("a_kurz_zaplnen").style.visibility='hidden';
					document.getElementById("a_kurz_zaplnen1").style.display='none';
					document.getElementById("a_kurz_zaplnen1").style.visibility='hidden';
					document.getElementById("reg_form").style.display='block';
					document.getElementById("reg_form").style.visibility='visible';
					
					document.getElementById("a_kurz_zaplnen").innerHTML = a_kurz_zaplnen.item(0).firstChild.data;
					
				}
				
}
			catch(e)
			{

			}
		}
		else
		{
			alert("There was a problem accessing the server: " + xmlHttp.statusText);
		}
	}
}