var fadeTime = 500; // rychlost změny v ms
var autoFade = 6000; // rychlost automatické změny v ms
var fading = false;
var boxAct = 1;
var lastChange = false;

function autoChange()
{
    clearTimeout(lastChange);
    lastChange = setInterval("autoChanging()", autoFade);        
}

function autoChanging()
{
    var odkazy = document.getElementById('pathPageBox').getElementsByTagName('a');
    
    if (boxAct == 6)
    {
        eval("change(1, '" + odkazy[1].getAttribute("href") + "')");
    }
    else
    {
        eval("change(" + (boxAct + 1) + ", '" + odkazy[boxAct + 1].getAttribute("href") + "')");
    }
        
}

function change(boxNum, url)
{
    
    if (boxNum < 1 || boxNum > 6)
        boxNum = 1;
    
    var box = document.getElementById('pathBox0'+boxNum);
        
    if (boxNum == boxAct || fading)
        return false;
        
    fading = true;
    box.FadeTimeLeft = fadeTime;
    autoChange();
    
    setTimeout("fade(" + new Date().getTime() + ", 'pathBox0" + boxNum + "', 'pathBox0" + boxAct + "')", 33);
     
    var pages = document.getElementById('pathPageBox').getElementsByTagName('a');
    
    pages[boxNum].className = "pageAct";
    pages[boxNum].setAttribute("class", "pageAct");
    pages[boxAct].className = "page";
    pages[boxAct].setAttribute("class", "page");
    document.getElementById('pathPageBox').getElementsByTagName('a')[0].href = url;
    boxAct = boxNum;
    return false;
}

function fade(lastTick, showBox, hideBox)
{  
  var show = document.getElementById(showBox);
  var hide = document.getElementById(hideBox);
  
  var curTick = new Date().getTime();
  var elapsedTicks = curTick - lastTick;
 
  if(show.FadeTimeLeft <= elapsedTicks)
  {
    show.style.opacity = '1';
    hide.style.opacity = '0';
    show.style.filter = 'alpha(opacity = 100)';
    hide.style.filter = 'alpha(opacity = 0)';
    
    fading = false;
    
    return;
  }
  else
  {
    show.FadeTimeLeft -= elapsedTicks;
    var newHideVal = show.FadeTimeLeft/fadeTime;
    var newShowVal = 1 - newHideVal;

    show.style.opacity = newShowVal;
    show.style.filter = 'alpha(opacity = ' + (newShowVal*100) + ')';
    hide.style.opacity = newHideVal;
    hide.style.filter = 'alpha(opacity = ' + (newHideVal*100) + ')';
 
    setTimeout("fade(" + new Date().getTime() + ", '" + showBox + "', '" + hideBox + "')", 33);
  }
}