function is_empty(str) {
  if (!str || str.length < 1) return false;
  return true;
}

function empty_query_string(str) {
  result = is_empty(str.value);
  if (result == false) {
    alert("Zadejte dotaz");
    str.focus();
    return false;
  } else {
    return true;
  }
}

function paging(formname, id) {
	document.getElementById(formname).event_paging.value = id;
	document.getElementById(formname).submit();
}

function fill_click(entity)
{
	entity.select();
}

function show_forum_form(id_auction_forum)
{
	document.getElementById("auctionQuery").style.display = 'block';
	document.getElementById('queryString').focus();
	document.getElementById('parentQuery').value = id_auction_forum;	
}

function forum_select_all()
{
	var rows = document.getElementsByName('query_selection[]');
	var checkbox;
	
   for (var i=0; i < rows.length; i++ )
	{
		checkbox = rows[i];

		if( checkbox && checkbox.type == 'checkbox' )
		{
			checkbox.checked = true;
		}
	}

}

function switch_display(to_hide, to_show, display_style)
{
	if (to_hide)
	{
		document.getElementById(to_hide).style.display = "none";
	}
	if (to_show)
	{
	  document.getElementById(to_show).style.display = display_style;
	}
}


function open_popup(link, title, width, height)
{
	window.open(link,title,'scrollbars=yes,location=no,width='+width+',height='+height+'');
}

// time counter
function p (i)	{
   return Math.floor(i / 10) + "" + i % 10;
}
function trunc (i) {
   var j = Math.round(i * 100);
   return Math.floor(j / 100) + (j % 100 > 0 ? "." + p(j % 100) : "");
}

function CounterTime() {}
					
CounterTime.prototype.setServerTime = function(datum) {
   this.servertime = new Date(datum.replace(/-/g, "/"));
}					
CounterTime.prototype.setEndsTime = function(datum) {
   this.endtime = new Date(datum.replace(/-/g, "/"));
}
CounterTime.prototype.synchronizeWith = function(url) {
   this.synchronizeWithUrl = url;
}					
CounterTime.prototype.bindWith = function(elm) {
   this.elm = elm;
}
CounterTime.prototype.setDifference = function() {
   var date1 = this.servertime;
   var date2 = this.endtime;
   this.difference = date2.getTime() - date1.getTime();						
}               					
CounterTime.prototype.redraw = function() 
{
   this.difference -= 1000;	   
   var sec = this.difference
                  
   if (isNaN(sec))
   {  
      this.elm.innerHTML = "aukce ukončena"; 	 
   	return;
   }
   if (sec < 0)
   {
      this.elm.innerHTML = "aukce ukončena";	 
   	return;
   }
   
   var second = 1000, minute = 60 * second, hour = 60 * minute, day = 24 * hour;
   
   var days = Math.floor(sec / day);
   sec -= days * day;
   var hours = Math.floor(sec / hour);
   sec -= hours * hour;
   var minutes = Math.floor(sec / minute);
   sec -= minutes * minute;
   var seconds = Math.floor(sec / second);						
   this.elm.innerHTML = days + "d " + hours + "h " + minutes + "m " + seconds + "s";
}

CounterTime.prototype.run = function() {
   cntr = this;
   if (this.difference > 0) {
   	this.redraw();							
   	window.clearTimeout(this.timeout);
   } else {
   	this.elm.innerHTML = "aukce ukončena"; 
   	return;
   }
   this.timeout = window.setTimeout('cntr.run()', 1000);
}