/**
  * 미리보기
  *
  * @return \Illuminate\Http\RedirectResponse
  * @throws \Xpressengine\Keygen\UnknownGeneratorException
  */
 public function preview()
 {
     /** @var \Illuminate\Http\Request $request */
     $request = app('request');
     if ($this->permissionHandler->hasCreate($this->boardId) === false) {
         throw new AccessDeniedHttpException();
     }
     $user = Auth::user();
     // get rules
     /** @var \Xpressengine\Plugins\Board\Validator $validator */
     $validator = app('xe.board.validator');
     $rules = $validator->makeRule($this->config);
     if ($user instanceof Guest) {
         $rules = array_merge($rules, $validator->guestStore());
     }
     $this->validate($request, $rules);
     $doc = new DocumentEntity($this->handler->documentFilter($request->all()));
     $doc->id = 'preview-' . (new Keygen())->generate();
     $doc->instanceId = $this->boardId;
     $doc->createdAt = date('Y-m-d H:i:s');
     if ($user instanceof Guest) {
         $doc->setUserType($doc::USER_TYPE_GUEST);
     }
     $doc->setAuthor($user);
     $item = $this->handler->makeItem($doc);
     /** @var \Xpressengine\Storage\Storage $storage */
     if (($fileIds = $request->get('_files')) !== null) {
         $storage = app('xe.storage');
         $item->setFiles($storage->getsIn($fileIds));
     }
     $formColumns = $this->configHandler->formColumns($this->boardId);
     return Presenter::make('preview', ['config' => $this->config, 'item' => $item, 'handler' => $this->handler, 'formColumns' => $formColumns]);
 }