fix: resolve event deletion 500 error with proper foreign key handling

- Rewrite delete endpoint to use database transaction
- Delete related data in correct order: access_logs, email_queue, photos, photo_categories, then event
- Add cleanup for storage folders and archive files
- Improve error messages for better debugging

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

backend/src/routes/adminEvents.js

@@ -393,13 +393,53 @@ router.delete('/:id', adminAuth, async (req, res) => {
       return res.status(404).json({ error: 'Event not found' });
     }
 
-    // Delete associated photos
-    await db('photos').where('event_id', id).del();
+    // Start a transaction to ensure all deletions succeed or fail together
+    await db.transaction(async (trx) => {
+      // 1. Delete access logs
+      await trx('access_logs').where('event_id', id).del();
 
-    // Delete event
-    await db('events').where('id', id).del();
+      // 2. Delete email queue entries
+      await trx('email_queue').where('event_id', id).del();
 
-    // Log activity
+      // 3. Delete photos (this will also handle hero_photo_id foreign key)
+      await trx('photos').where('event_id', id).del();
+
+      // 4. Delete categories (photo_categories has CASCADE delete for event_id)
+      await trx('photo_categories').where('event_id', id).del();
+
+      // 5. Finally delete the event
+      await trx('events').where('id', id).del();
+
+      // Delete event folder from storage if it exists
+      if (event.folder_path) {
+        const storagePath = process.env.STORAGE_PATH || path.join(__dirname, '../../../storage');
+        const eventFolderPath = path.join(storagePath, 'events', 'active', event.folder_path);
+        
+        try {
+          const fsPromises = require('fs').promises;
+          await fsPromises.rm(eventFolderPath, { recursive: true, force: true });
+        } catch (err) {
+          console.error('Failed to delete event folder:', err);
+          // Don't fail the transaction if folder deletion fails
+        }
+      }
+
+      // Delete archive if exists
+      if (event.archive_path) {
+        const storagePath = process.env.STORAGE_PATH || path.join(__dirname, '../../../storage');
+        const archivePath = path.join(storagePath, event.archive_path);
+        
+        try {
+          const fsPromises = require('fs').promises;
+          await fsPromises.unlink(archivePath);
+        } catch (err) {
+          console.error('Failed to delete archive file:', err);
+          // Don't fail the transaction if file deletion fails
+        }
+      }
+    });
+
+    // Log activity (outside transaction)
     await logActivity('event_deleted',
       { event_name: event.event_name },
       null,
@@ -409,7 +449,19 @@ router.delete('/:id', adminAuth, async (req, res) => {
     res.json({ message: 'Event deleted successfully' });
   } catch (error) {
     console.error('Error deleting event:', error);
-    res.status(500).json({ error: 'Failed to delete event' });
+    
+    // Provide more specific error messages
+    if (error.message && error.message.includes('foreign key constraint')) {
+      res.status(500).json({ 
+        error: 'Cannot delete event due to existing references. Please contact support.',
+        details: error.message 
+      });
+    } else {
+      res.status(500).json({ 
+        error: 'Failed to delete event',
+        details: process.env.NODE_ENV === 'development' ? error.message : undefined
+      });
+    }
   }
 });