Fix: Use RPC for submission claims

src/hooks/useModerationQueue.ts

@@ -324,20 +324,19 @@ export const useModerationQueue = (config?: UseModerationQueueConfig) => {
         .single();
 
       const expiresAt = new Date(Date.now() + 15 * 60 * 1000);
-      const now = new Date().toISOString();
       
-      const { error } = await supabase
-        .from('content_submissions')
-        .update({
-          assigned_to: user.id,
-          assigned_at: new Date().toISOString(),
-          locked_until: expiresAt.toISOString(),
-        })
-        .eq('id', submissionId)
-        .or(`assigned_to.is.null,locked_until.lt."${now}"`); // Only if unclaimed or lock expired
+      const { data, error } = await supabase.rpc('claim_specific_submission', {
+        p_submission_id: submissionId,
+        p_moderator_id: user.id,
+        p_lock_duration: '15 minutes',
+      });
 
       if (error) throw error;
 
+      if (!data) {
+        throw new Error('Submission is already claimed or no longer available');
+      }
+
       setCurrentLock({
         submissionId,
         expiresAt,

src/integrations/supabase/types.ts

@@ -5403,6 +5403,14 @@ export type Database = {
           waiting_time: unknown
         }[]
       }
+      claim_specific_submission: {
+        Args: {
+          p_lock_duration?: unknown
+          p_moderator_id: string
+          p_submission_id: string
+        }
+        Returns: boolean
+      }
       cleanup_expired_sessions: { Args: never; Returns: undefined }
       cleanup_old_page_views: { Args: never; Returns: undefined }
       cleanup_old_request_metadata: { Args: never; Returns: undefined }