var xmlHttp;
var inProgress;

function GetXmlHttpObject(){
var xmlHttp = null;

	try {
	  // Firefox, Opera 8.0+, Safari
	  xmlHttp = new XMLHttpRequest();
	  }
	catch (e) {
	  // Internet Explorer
	  try {
			xmlHttp = new ActiveXObject("Msxml2.XMLHTTP");
		}
	  catch (e){
			xmlHttp = new ActiveXObject("Microsoft.XMLHTTP");
		}
	  }
	  
	return xmlHttp;

}


// Calculate the rating

function rate(id){

	if(inProgress) return;
	inProgress = true;
	xmlHttp = GetXmlHttpObject();
	
	if(xmlHttp == null){
		alert ("Your browser does not support AJAX!");
		return;
	  }
	  
	var msgHolder = document.getElementById('rt');
	var btnHolder = document.getElementById('rb');
	msgHolder.innerHTML = 'odesílám...';

	xmlHttp.onreadystatechange = function(){

	
		if (xmlHttp.readyState == 4){ 
			
			var res = xmlHttp.responseText;
			
			
			if(res.indexOf('blocked')>=0){
				msgHolder.innerHTML = 'už jsi hlasoval';
			}
			else{
				var numHolder = document.getElementById('points');
				numHolder.innerHTML = res+'';
				msgHolder.innerHTML = 'díky za hlas';
				
				inProgress =false;
			}
		 btnHolder.getElementsByTagName('a')[0].onclick = 'return false;';
		btnHolder.getElementsByTagName('a')[0].removeAttribute('href','javascript:void(0)');
		  }
		}
	
	var url = "/rating.php";
	var params = "id="+id+"&rating=1";
	xmlHttp.open("POST",url,true);
	xmlHttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
	xmlHttp.setRequestHeader("Content-length", params.length);
	xmlHttp.setRequestHeader("Connection", "close");
	xmlHttp.send(params);

}