/**
  * Validate the form
  *
  * @return	void
  */
 private function validateForm()
 {
     // is the form submitted?
     if ($this->frm->isSubmitted()) {
         // cleanup the submitted fields, ignore fields that were added by hackers
         $this->frm->cleanupFields();
         // shorten fields
         $txtName = $this->frm->getField('name');
         $rbtDefaultForLanguage = $this->frm->getField('default');
         // validate fields
         if ($txtName->isFilled(BL::err('NameIsRequired'))) {
             if ($txtName->getValue() != $this->record['name'] && BackendMailmotorModel::existsGroupByName($txtName->getValue())) {
                 $txtName->addError(BL::err('GroupAlreadyExists'));
             }
         }
         // no errors?
         if ($this->frm->isCorrect()) {
             // build item
             $item['id'] = $this->id;
             $item['name'] = $txtName->getValue();
             $item['language'] = $rbtDefaultForLanguage->getValue() === '0' ? null : $rbtDefaultForLanguage->getValue();
             $item['is_default'] = $rbtDefaultForLanguage->getChecked() ? 'Y' : 'N';
             // update the item
             BackendMailmotorCMHelper::updateGroup($item);
             // check if all default groups were set
             BackendMailmotorModel::checkDefaultGroups();
             // trigger event
             BackendModel::triggerEvent($this->getModule(), 'after_edit_group', array('item' => $item));
             // everything is saved, so redirect to the overview
             $this->redirect(BackendModel::createURLForAction('groups') . '&report=edited&var=' . urlencode($item['name']) . '&highlight=id-' . $item['id']);
         }
     }
 }