$chapter->book_id = $parentBook->id;
$chapter->priority = (new BookContents($parentBook))->getLastPriority() + 1;
$this->baseRepo->create($chapter, $input);
$chapter->book_id = $parentBook->id;
$chapter->priority = (new BookContents($parentBook))->getLastPriority() + 1;
$this->baseRepo->create($chapter, $input);