function show_foto(ktora) {
    var posun_top=50;
		var sirka_fotky=500;
		var left=Math.round((window.innerWidth-sirka_fotky+20)/2);		
		

    if (document.getElementById) { // DOM3 = IE5, NS6
    	 document.getElementById('foto').style.top = document.body.scrollTop+ posun_top;
//    	 document.getElementById('foto').style.left = left;
			 document.getElementById('foto').style.visibility = 'visible';		 
    }
    else {	
      if (document.layers) { // Netscape 4

      	 document.foto.top = document.body.scrollTop+ posun_top;
//      	 document.foto.left = left;				 
				 document.foto.visibility = 'visible';
      }
      else { // IE 4
      		 document.all.foto.style.top=document.body.scrollTop+ posun_top;
//      		 document.all.foto.style.left=left;					 
					 document.all.foto.style.visibility = 'visible';
      }
    } 	
		start_HTTP_request('id='+ktora);	
}
function hide_foto() {
    if (document.getElementById) { // DOM3 = IE5, NS6
			 document.getElementById('foto').style.visibility = 'hidden';			 
    }
    else {
      if (document.layers) { // Netscape 4
				 document.foto.visibility = 'hidden';
      }
      else { // IE 4
					 document.all.foto.style.visibility = 'hidden';
      }
    } 	
		start_HTTP_request('id_foto='+ktora);	
}


function start_HTTP_request(start) {

 var get_all='?'+start;
	if (window.XMLHttpRequest) { // Mozilla, Safari,...
      var XHR = new XMLHttpRequest();
  } else if (window.ActiveXObject) { // IE
      try {
      var XHR = new ActiveXObject("Msxml2.XMLHTTP");
      } catch (e) {
          try {
          		var XHR = new ActiveXObject("Microsoft.XMLHTTP");
          } catch (e) {}
      }
  }
  XHR.onreadystatechange = function() {
			check_status(XHR);
	}	
  d = new Date();
  s = d.getMilliseconds();
	
	var stranka="recept.php"+get_all+'&s='+s;
  XHR.open("GET", stranka , true);
  XHR.send(null);
  
}

function check_status (x) {
   if (x.readyState == 4) {
			if (x.status == 200) {
						 writeUserData(x);
			} else {
				alert('Požiadavku sa nepodarilo spracovať.');
			}
	 }
}

function writeUserData(x) {
		var a = x.responseText;	
		if (a!="") {
        var objChat = document.getElementById("foto");
    		objChat.innerHTML=a;
		}		
}