function getQuerystring(key, default_)
{
  if (default_==null) default_=""; 
  key = key.replace(/[\[]/,"\\\[").replace(/[\]]/,"\\\]");
  var regex = new RegExp("[\\?&]"+key+"=([^&#]*)");
  var qs = regex.exec(window.location.href);
  if(qs == null)
    return default_;
  else
    return qs[1];
}

var slideshow = getQuerystring('slideshow');



var timer = null;
var duration = null;
    $(document).ready(function(){
            if(slideshow == '1'){
                $("#slideshow_start_stop").html("zastavit slideshow");
                duration = 6000;
            }
            
            if(duration!=null) {
                    if($("a#dalsi").attr("href")!=null){
                            timer = setInterval(function(){
                                    window.location = $("a#dalsi").attr("href")+"?slideshow=1#foto_nav"; return false; 
                                }, duration);
                        }
                        else {
                            timer = setInterval(function(){
                                    window.location = $("a#album").attr("href"); return false; 
                                }, duration);
                        }
                }
            
            $("a#slideshow_start_stop").click(function(){
                if($("#slideshow_start_stop").html() == "spustit slideshow") {
                    duration = 6000;
                    $("#slideshow_start_stop").html("zastavit slideshow");
                    if($("a#dalsi").attr("href")!=null){
                        timer = setInterval(function(){
                                window.location = $("a#dalsi").attr("href")+"?slideshow=1#foto_nav"; return false; 
                            }, duration);
                    }
                    else {
                        timer = setInterval(function(){
                                window.location = $("a#album").attr("href"); return false; 
                            }, duration);
                    }
                }
                else if($("#slideshow_start_stop").html() == "zastavit slideshow") {
                    duration = null;
                    $("#slideshow_start_stop").html("spustit slideshow");
                    clearInterval(timer)
                }
            });return false;
                
    });