/////////////////////////////////////////////////////////////////////////////

// variables

//slideshow variables 
var running;
var current; 

// cookie variables
var today = new Date();
var zero_date = new Date(0,0,0);

//var todays_date = new Date(today.getYear(),today.getMonth(),today.getDate(),0,0,0);
//var expires_date = new Date(todays_date.getTime() + (8 * 7 * 86400000));
//var expires_date = new Date(zero_date);

// scroll variables

// browserweiche
ie = ((document.all) && (window.offscreenBuffering)) ? true : false;
nn = ((document.captureEvents) && (!document.getElementById)) ? true : false;
mz = ((document.getElementById) && (!document.all) && (document.documentElement)) ? true : false;
op = ((document.getElementById) && (navigator.userAgent.indexOf('Opera') != -1)) ? true : false
sf = (navigator.vendor.indexOf('Apple') > -1);
ff3 = (navigator.userAgent.indexOf('Firefox/3') > -1);

//if(ff3) document.body.onselectstart = null; 

/////////////////////////////////////////////////////////////////////////////
// code to execute directly 


/////////////////////////////////////////////////////////////////////////////
// functions

// menu
function showMenu(name) {
   showLayer(name);
}

function hideMenu(name) {
   hideLayer(name);
}

// turn layers on and off
function showLayer(name) {
   eval(document.getElementById(name)).style.visibility = 'visible';
}
function hideLayer(name) {
   eval(document.getElementById(name)).style.visibility = 'hidden';
}

function activateImg(num_elements, active_id) {
   for (x=0;x<num_elements;x++) {
      hideLayer("collectionpic" + x); //img_element);
   }
   showLayer("collectionpic" + active_id); //img_element);
}

// project picture viewer
function activateProjectMedium(num_elements, active_id) {
   for (x=0;x<num_elements;x++) {
      hideLayer("projectpic" + x); //img_element);
      if(x>0 && document.getElementById("imagedescription" + x) != null)
	 hideLayer("imagedescription" + x); 
      eval(document.getElementById("flippernavi" + x)).style.color = 'black';
   }
   showLayer("projectpic" + active_id); //img_element);
   hideLayer("projectdescription");
   eval(document.getElementById("flippernavi" + active_id)).style.color = '#ee1c24';
   if(active_id > 0 && document.getElementById("imagedescription" + active_id) != null)
      showLayer("imagedescription" + active_id); 
   else if(active_id == 0) 
      showLayer("projectdescription"); 
   document.getElementById("dummy").focus();
}

function activateNewsMedium(num_elements, active_id) {
   for (x=0;x<num_elements;x++) {
      hideLayer("newsimage_cont" + x);
   }
   showLayer("newsimage_cont" + active_id);
   showLayer("back_button");
   hideLayer("textfield");
   hideLayer("scrollbar");
}

function activateProjectDescription(num_elements) {
   for (x=0;x<num_elements;x++) {
      hideLayer("projectpic" + x); //img_element);
      eval(document.getElementById("projectpicnavi" + x)).src = 'img/scheibe.png';
   }
   showLayer("projectdescription"); 
   document.getElementById("initial").src = 'img/_scheibe.png';
   document.getElementById("dummy").focus();
}

function activateNewsList(num_elements) {
   for (x=0;x<num_elements;x++) {
      hideLayer("newsimage_cont" + x);
      //eval(document.getElementById("projectpicnavi" + x)).src = 'img/scheibe.png';
   }
   hideLayer("back_button");
   showLayer("textfield");
   showLayer("scrollbar");
   //document.getElementById("initial").src = 'img/_scheibe.png';
   //document.getElementById("dummy").focus();
}

// picture viewer
function hidePic(medium_id) {
   if(ie) document.all('collection_'+medium_id).style.visibility='hidden';
   else document.getElementById('collection_'+medium_id).style.visibility='hidden';
}
function showPic(medium_id) {
   if(ie) document.all('collection_'+medium_id).style.visibility='visible';
   else document.getElementById('collection_'+medium_id).style.visibility='visible';
}

// preload slideshow images, execute immediatly
function preload_slideshow_images() {
   if(document.images && slideshow_images) {
   var preload = new Array();
      for(x=0;x<slideshow_images.length;x++) {
	 preload[x] = new Image();
	 preload[x].src = slideshow_images[x];
      }
   }
}

function slide(image_o, image_a, time) {
  // pr0tect against textbrowsers
  if (document.images) {
    image_array = image_a;
    image_object = image_o;
    if (running) clearInterval(running);
    running = setInterval("shiftpix()",time);
  }
}

function stopslide() {
   clearInterval(running);
}

function shiftpix () {
  if (current < image_array.length-1) current++;
  else current = 0;
  image_object.src = image_array[current];
}