Merge pull request #6625 from WoltLab/63-collection-attachments-trait

Add trait for providing of attachments in dbo collections

Author: BurntimeX

wcfsetup/install/files/lib/data/TCollectionAttachments.class.php

@@ -0,0 +1,82 @@
+<?php
+
+namespace wcf\data;
+
+use wcf\data\attachment\Attachment;
+use wcf\data\attachment\GroupedAttachmentList;
+
+/**
+ * Trait for dbo collections with attachments.
+ *
+ * @author      Marcel Werk
+ * @copyright   2001-2026 WoltLab GmbH
+ * @license     GNU Lesser General Public License <http://opensource.org/licenses/lgpl-license.php>
+ * @since       6.3
+ */
+trait TCollectionAttachments
+{
+    private GroupedAttachmentList $attachments;
+
+    /**
+     * @return Attachment[]
+     */
+    public function getAttachments(DatabaseObject $object): array
+    {
+        if (!$this->hasAttachments($object)) {
+            return [];
+        }
+
+        $this->loadAttachments();
+
+        return $this->attachments->getGroupedObjects($object->getObjectID());
+    }
+
+    private function loadAttachments(): void
+    {
+        if (isset($this->attachments)) {
+            return;
+        }
+
+        $this->attachments = new GroupedAttachmentList($this->getAttachmentObjectType());
+
+        $objectIDs = $this->getAttachmentObjectIDs();
+        if ($objectIDs === []) {
+            return;
+        }
+
+        $this->attachments->getConditionBuilder()->add('attachment.objectID IN (?)', [$objectIDs]);
+        $this->attachments->readObjects();
+        $this->attachments->setPermissions($this->getAttachmentPermissions());
+    }
+
+    protected abstract function getAttachmentObjectType(): string;
+
+    /**
+     * @return array<string, bool>
+     */
+    protected function getAttachmentPermissions(): array
+    {
+        return [
+            'canDownload' => true,
+            'canViewPreview' => true,
+        ];
+    }
+
+    protected function hasAttachments(DatabaseObject $object): bool
+    {
+        return $object->attachments > 0;
+    }
+
+    /**
+     * @return list<int>
+     */
+    private function getAttachmentObjectIDs(): array
+    {
+        \assert($this instanceof DatabaseObjectCollection);
+
+        return \array_map(
+            static fn(DatabaseObject $object) => $object->getObjectID(),
+            \array_filter($this->getObjects(), fn(DatabaseObject $object) => $this->hasAttachments($object))
+        );
+    }
+}