public function getFullCategoryTree() {
        $db = \Libs\DB::getInstance();
        $select = $join = $categories = '';
        $db->query("SELECT COUNT(DISTINCT parent) as deep FROM category");
        $deep = $db->getResult();
        for ($i = 1; $i <= $deep[0]->deep; $i++) {
            $select .="t$i.lang1 AS lev$i,";
        }
        for ($i = 1; $i <= $deep[0]->deep - 1; $i++) {
            $join .= " LEFT JOIN category AS t" . ($i + 1) . " ON t" . ($i + 1) . ".parent = t" . $i . ".cid";
        }

        $sql = 'SELECT ' . trim($select, ',') . ' FROM category AS t1' . $join . ' WHERE t1.cid =1';
        $db->query($sql);
        return $db->getResult();
    }