/**
 * Galerie Absatz
 */
function sg_galery(num, per_page, object) {

   var num_entrys = num;
   var entry_per_page = per_page;
   var page = 0;
   var object_name = object;

   this.next = function() {
      page++;
      jump();
   }

   this.prev = function() {
      page--;
      jump();
   }

   this.init = function() {
      page=0;
      jump();
   }

   function jump() {

      if(page>0) document.getElementById(object_name+'_prev').style.display="inline";
      else document.getElementById(object_name+'_prev').style.display="none";
      if(page<(num_entrys/entry_per_page-1)) document.getElementById(object_name+'_next').style.display="inline"
      else document.getElementById(object_name+'_next').style.display="none"

      for(i=1; i<=num_entrys; i++) document.getElementById(object_name+'_'+i).style.display="none";

      var target = (page*entry_per_page)+entry_per_page;
      if(target>num_entrys) target = num_entrys;
      if(page<1) var i = 1; else var i = (page*entry_per_page)+1;

      for(i=i; i<=target; i++) document.getElementById(object_name+'_'+i).style.display="inline";

   }

}