var http = createRequestObject();
function createRequestObject() 
{
	var ro;
	var browser = navigator.appName;
	if(browser == "Microsoft Internet Explorer")
	{
		ro = new ActiveXObject("Microsoft.XMLHTTP");
	}
	else
	{
		ro = new XMLHttpRequest();
	}
	return ro;
}

function changeuser(field,but)
{
	if(field.value == '')
	{
		document.getElementById(but).disabled = true;
	}
	else
	{
		document.getElementById(but).disabled = false;
	}
}
function checkavail(field,utype)
{
	username = document.getElementById(field).value;
	
	if(username.length < 4)
	{
		document.getElementById('availres').innerHTML = 'Korisničko ime "'+username+'" je prekratko';
		return;
	}
	else if(username.length > 16)
	{
		document.getElementById('availres').innerHTML = 'Korisničko ime "'+username+'" je predugačko';
		return;
	}
	
	http.open('get', 'http://www.berzica.com/signup.php?type='+utype+'&avail='+username);
    http.onreadystatechange = availResponse;
    http.send(null);
}
function availResponse() 
{
	if(http.readyState == 4)
	{
        var response = http.responseText;
				
		returned = response.split('|');

		if(response.indexOf('|' != -1)) 
		{
			var username=returned[0];
			var status=returned[1];
			
			if(status == 1)
			{
				document.getElementById('availres').innerHTML = 'Korisničko ime "'+username+'" je slobodno';
			}
			else if(status == 2)
			{
				document.getElementById('availres').innerHTML = 'Korisničko ime "'+username+'" nije dozvoljeno';
			}
			else
			{
				document.getElementById('availres').innerHTML = 'Korisničko ime "'+username+'" je zauzeto!';
			}
		}
	}
}
function MM_jumpMenu(targ,selObj,restore){ //v3.0
	if(selObj.options[selObj.selectedIndex].value != '')
	{
		eval(targ+".location='"+selObj.options[selObj.selectedIndex].value+"'");
		if (restore) selObj.selectedIndex=0;
	}
}