FEATURE: Prevent deletion of referenced asset collections

Resolves: #245

Classes/GraphQL/Resolver/Type/AssetCollectionResolver.php

@@ -17,6 +17,8 @@
 use Flowpack\Media\Ui\Service\AssetCollectionService;
 use Neos\Flow\Annotations as Flow;
 use Neos\Media\Domain\Repository\AssetRepository;
+use Neos\Neos\Domain\Model\Site;
+use Neos\Neos\Domain\Repository\SiteRepository;
 use t3n\GraphQL\ResolverInterface;
 use Neos\Media\Domain\Model\AssetCollection;
 use Neos\Flow\Persistence\PersistenceManagerInterface;
@@ -44,6 +46,14 @@ class AssetCollectionResolver implements ResolverInterface
      */
     protected $assetCollectionService;
 
+    /**
+     * @Flow\Inject
+     * @var SiteRepository
+     */
+    protected $siteRepository;
+
+    protected array|null $siteDefaultAssetCollections = null;
+
     public function id(AssetCollection $assetCollection): string
     {
         return $this->persistenceManager->getIdentifierByObject($assetCollection);
@@ -53,4 +63,25 @@ public function assetCount(AssetCollection $assetCollection): int
     {
         return $this->assetCollectionService->getAssetCollectionAssetCount($this->id($assetCollection));
     }
+
+    /**
+     * Returns true if the asset collection is empty and is not assigned as default collection for a site
+     */
+    public function canDelete(AssetCollection $assetCollection): bool
+    {
+        if ($this->siteDefaultAssetCollections === null) {
+            $this->siteDefaultAssetCollections = [];
+            /** @var Site $site */
+            foreach ($this->siteRepository->findAll() as $site) {
+                $siteAssetCollection = $site->getAssetCollection();
+                if (!$siteAssetCollection) {
+                    continue;
+                }
+                $this->siteDefaultAssetCollections[$this->id($site->getAssetCollection())] = true;
+            }
+        }
+
+        return !array_key_exists($this->id($assetCollection), $this->siteDefaultAssetCollections)
+            && $this->assetCount($assetCollection) === 0;
+    }
 }

Classes/GraphQL/Resolver/Type/MutationResolver.php

@@ -652,10 +652,13 @@ public function deleteAssetCollection($_, array $variables): array
             throw new Exception('Asset collection not found', 1591972269);
         }
 
+        if ($this->assetCollectionService->getAssetCollectionAssetCount($id) > 0) {
+            throw new Exception('Asset collection is not empty', 1730102095);
+        }
+
         /** @noinspection PhpUndefinedMethodInspection */
-        foreach ($this->siteRepository->findByAssetCollection($assetCollection) as $site) {
-            $site->setAssetCollection(null);
-            $this->siteRepository->update($site);
+        if ($this->siteRepository->findOneByAssetCollection($assetCollection)) {
+            throw new Exception('Asset collection is referenced as default collection of a site', 1730101671);
         }
 
         $this->assetCollectionRepository->remove($assetCollection);

Resources/Private/GraphQL/schema.root.graphql

@@ -279,6 +279,7 @@ type AssetCollection {
     tags: [Tag!]!
     assetCount: Int!
     path: AssetCollectionPath
+    canDelete: Boolean!
 }
 
 """

Resources/Private/JavaScript/asset-collections/src/components/DeleteButton.tsx

@@ -74,7 +74,7 @@ const DeleteButton: React.FC = () => {
             style="transparent"
             hoverStyle="error"
             disabled={
-                (!selectedAssetCollection || !config.canManageAssetCollections) &&
+                (!selectedAssetCollection || !config.canManageAssetCollections || !selectedAssetCollection.canDelete) &&
                 (!selectedTag || !config.canManageTags)
             }
             title={translate('assetCollectionTree.toolbar.delete', 'Delete')}

Resources/Private/JavaScript/asset-collections/src/fragments/assetCollection.ts

@@ -14,6 +14,7 @@ export const ASSET_COLLECTION_FRAGMENT = gql`
         }
         assetCount
         path
+        canDelete
     }
     ${TAG_FRAGMENT}
 `;

Resources/Private/JavaScript/asset-collections/typings/AssetCollection.ts

@@ -13,4 +13,5 @@ interface AssetCollection extends GraphQlEntity {
     tags?: Tag[];
     assetCount: number;
     path?: string;
+    canDelete: boolean;
 }