// stores the reference to the XMLHttpRequest object
var xmlHttp = createXmlHttpRequestObject();
// retrieves the XMLHttpRequest object
function createXmlHttpRequestObject()
{
	// will store the reference to the XMLHttpRequest object
	var xmlHttp;
	// if running Internet Explorer
	if(window.ActiveXObject)
	{
		try
		{
			xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
		}
		catch (e)
		{
			xmlHttp = false;
		}
	}
	// if running Mozilla or other browsers
	else
	{
		try 
		{
			xmlHttp = new XMLHttpRequest();
		}
		catch (e)
		{
			xmlHttp = false;
		}
	}
	// return the created object or display an error message
	if (!xmlHttp)
		alert("Error creating the XMLHttpRequest object.");
	else
		return xmlHttp;
}

function GetOrase(OrasID)
{
	// proceed only if the xmlHttp object isn't busy
	if (xmlHttp.readyState == 4 || xmlHttp.readyState == 0)
	{
		params = 'JudetID=' + document.getElementById('sJudetID').value;
		if(OrasID != 0)
			params += '&OrasID=' + OrasID;
		
		// execute the quickstart.php page from the server
		xmlHttp.open("GET", ru + "req-location.php?" + params, true);
		// define the method to handle server responses
		xmlHttp.onreadystatechange = ShowOrase;
		// make the server request
		xmlHttp.send(null);
	}
	else
		// if the connection is busy, try again after one second
		setTimeout('GetOrase()', 1000);
}

function ShowOrase()
{
	// move forward only if the transaction has completed
	if (xmlHttp.readyState == 4)
	{
		// status of 200 indicates the transaction completed successfully
		if (xmlHttp.status == 200)
		{
			// extract the XML retrieved from the server
			response = xmlHttp.responseText;
			// update the client display using the data received from the server
			document.getElementById("Orase").innerHTML = response;
		}
	}
}

// make asynchronous HTTP request using the XMLHttpRequest object
function process()
{
	// proceed only if the xmlHttp object isn't busy
	if (xmlHttp.readyState == 4 || xmlHttp.readyState == 0)
	{
		// retrieve the name typed by the user on the form
		name = encodeURIComponent(document.getElementById("myName").value);
		// execute the quickstart.php page from the server
		xmlHttp.open("GET", ru + "req-location.php?name=" + name, true);
		// define the method to handle server responses
		xmlHttp.onreadystatechange = handleServerResponse;
		// make the server request
		xmlHttp.send(null);
	}
	else
		// if the connection is busy, try again after one second
		setTimeout('process()', 1000);
}

// executed automatically when a message is received from the server
function handleServerResponse()
{
	// move forward only if the transaction has completed
	if (xmlHttp.readyState == 4)
	{
		// status of 200 indicates the transaction completed successfully
		if (xmlHttp.status == 200)
		{
			// extract the XML retrieved from the server
			xmlResponse = xmlHttp.responseXML;
			// obtain the document element (the root element) of the XML structure
			xmlDocumentElement = xmlResponse.documentElement;
			// get the text message, which is in the first child of
			// the the document element
			helloMessage = xmlDocumentElement.firstChild.data;
			// update the client display using the data received from the server
			document.getElementById("divMessage").innerHTML =
			'<i>' + helloMessage + '</i>';
			// restart sequence
			setTimeout('process()', 1000);
		}
		// a HTTP status different than 200 signals an error
		else
		{
			alert("There was a problem accessing the server: " + xmlHttp.statusText);
		}
	}
}