function get_selection_page_set($site_id)
 {
     reason_include_once('minisite_templates/nav_classes/default.php');
     $pages = new MinisiteNavigation();
     $site = new entity($site_id);
     $pages->site_info = $site;
     $pages->init($site_id, id_of('minisite_page'));
     return $this->flatten_page_tree($pages->get_tree_data());
 }