/**
  * Get html for public and/or private notes
  *
  * @param bool $a_content_object
  * @param bool $a_enable_private_notes
  * @param bool $a_enable_public_notes
  * @param bool $a_enable_notes_deletion
  * @return string
  */
 function getNotesHTML($a_content_object = null, $a_enable_private_notes = true, $a_enable_public_notes = false, $a_enable_notes_deletion = false, $a_callback = null)
 {
     global $ilCtrl;
     include_once "Services/Notes/classes/class.ilNoteGUI.php";
     // scorm 2004 page gui
     if (!$a_content_object) {
         $notes_gui = new ilNoteGUI($this->notes_parent_id, (int) $this->obj->getId(), "pg");
         $a_enable_private_notes = true;
         $a_enable_public_notes = true;
         $a_enable_notes_deletion = false;
     } else {
         $notes_gui = new ilNoteGUI($a_content_object->getParentId(), $a_content_object->getId(), $a_content_object->getParentType());
     }
     if ($a_enable_private_notes) {
         $notes_gui->enablePrivateNotes();
     }
     if ($a_enable_public_notes) {
         $notes_gui->enablePublicNotes();
         if ((bool) $a_enable_notes_deletion) {
             $notes_gui->enablePublicNotesDeletion(true);
         }
     }
     if ($a_callback) {
         $notes_gui->addObserver($a_callback);
     }
     $next_class = $this->ctrl->getNextClass($this);
     if ($next_class == "ilnotegui") {
         $html = $this->ctrl->forwardCommand($notes_gui);
     } else {
         $html = $notes_gui->getNotesHTML();
     }
     return $html;
 }