Update app.py

app.py

@@ -233,7 +233,13 @@ class AdvancedRAG:
         return self.thread_id
 
     def upload_document(self, file) -> str:
-        # Always reset state for a new document
+        # Delete previous file from OpenAI if it exists
+        if self.file_ids:
+            for file_id in self.file_ids:
+                try:
+                    openai.files.delete(file_id)
+                except Exception as e:
+                    print(f"Warning: Could not delete file {file_id}: {e}")
         self.thread_id = None
         self.file_ids = []
         if hasattr(self, 'vector_store_id'):