private function save()
 {
     $this->config->set_forum_name($this->form->get_value('forum_name'));
     $this->config->set_number_topics_per_page($this->form->get_value('number_topics_per_page'));
     $this->config->set_number_messages_per_page($this->form->get_value('number_messages_per_page'));
     $this->config->set_read_messages_storage_duration($this->form->get_value('read_messages_storage_duration'));
     $this->config->set_max_topic_number_in_favorite($this->form->get_value('max_topic_number_in_favorite'));
     if ($this->form->get_value('edit_mark_enabled')) {
         $this->config->enable_edit_mark();
     } else {
         $this->config->disable_edit_mark();
     }
     if ($this->form->get_value('multiple_posts_allowed')) {
         $this->config->allow_multiple_posts();
     } else {
         $this->config->forbid_multiple_posts();
     }
     if ($this->form->get_value('connexion_form_displayed')) {
         $this->config->display_connexion_form();
     } else {
         $this->config->hide_connexion_form();
     }
     if ($this->form->get_value('left_column_disabled')) {
         $this->config->disable_left_column();
     } else {
         $this->config->enable_left_column();
     }
     if ($this->form->get_value('right_column_disabled')) {
         $this->config->disable_right_column();
     } else {
         $this->config->enable_right_column();
     }
     if ($this->form->get_value('message_before_topic_title_displayed')) {
         $this->config->display_message_before_topic_title();
         $this->config->set_message_before_topic_title($this->form->get_value('message_before_topic_title'));
         $this->config->set_message_when_topic_is_unsolved($this->form->get_value('message_when_topic_is_unsolved'));
         $this->config->set_message_when_topic_is_solved($this->form->get_value('message_when_topic_is_solved'));
         if ($this->form->get_value('message_before_topic_title_icon_displayed')) {
             $this->config->display_message_before_topic_title_icon();
         } else {
             $this->config->hide_message_before_topic_title_icon();
         }
     } else {
         $this->config->hide_message_before_topic_title();
     }
     $this->config->set_authorizations($this->form->get_value('authorizations')->build_auth_array());
     ForumConfig::save();
     ForumService::get_categories_manager()->regenerate_cache();
 }