public function reorderContent($type, $a, $b = null, $father = null)
    {
        $a = $this->getNode($type, $a, $father);
        $a->detach();

        if ($b) {
            $b = $this->getNode($type, $b, $father);
            $a->setBack($b->getBack());
            $a->setNext($b);

            if ($b->getBack()) {
                $b->getBack()->setNext($a);
            }

            $b->setBack($a);
        } else {
            $b = $this->getnode($type, null, $father);
            $a->setNext($b->getNext());
            $a->setBack($b);
            $b->setNext($a);
        }

        $this->manager->persist($a);
        $this->manager->persist($b);
        $this->manager->flush();
    }