Update app.py

app.py

@@ -157,7 +157,11 @@ def handle_pdf_upload(pdf_file):
     doc_id = document_manager.add_document(pdf_file.name)
     
     # Return updated dropdown list and the selected document ID
-    return document_manager.get_document_list(), doc_id
+    doc_list = document_manager.get_document_list()
+    # Only set the value if the list is not empty
+    selected_value = doc_id if doc_list else None
+    
+    return doc_list, selected_value
 
 # Function to get PDF content based on selected document
 def get_selected_document_content(doc_id):
@@ -620,7 +624,7 @@ def create_interface():
             inputs=[
                 input_text, image_input, audio_input, pdf_input, 
                 doc_selection, openai_api_key, reasoning_effort, 
-                model_choice, current_pdf_content
+                model_choice, current_pdf_content, chat_history_regular  # Added chat_history_regular to avoid creating new empty list
             ], 
             outputs=[
                 input_text, image_input, audio_input, pdf_input,