user() !== null; } public function rules(): array { return [ 'target_collection_id' => ['required', 'integer', 'exists:collections,id'], ]; } public function withValidator($validator): void { $validator->after(function ($validator): void { $targetCollectionId = (int) $this->input('target_collection_id'); $collection = $this->route('collection'); if ($collection instanceof Collection && $targetCollectionId === (int) $collection->id) { $validator->errors()->add('target_collection_id', 'Choose a different target collection.'); } }); } }