Update app.py

app.py

@@ -223,25 +223,32 @@ Answer conversationally:
     return f"{answer}\n\nSources Used:\n{metadata}"
 
 # =======================================================
-# 10) Gradio Chat Interface (INTRO only once)
+# 10) Gradio Chat Interface (INTRO only once, FIXED)
 # =======================================================
-INTRO_MESSAGE = {
-    "role": "assistant",
-    "content": INTRO_TEXT
-}
+
+INTRO_TUPLE = (None, INTRO_TEXT)
 
 def chat_api(message, history):
-    history.append({"role": "user", "content": message})
+    # history is a list of tuples: [(user, bot), ...]
+    
+    # Add user message
+    history.append((message, None))
+
+    # Generate bot reply
     reply = generate_with_rag(message)
-    history.append({"role": "assistant", "content": reply})
+
+    # Replace last tuple with completed (user, bot) pair
+    history[-1] = (message, reply)
+
     return history, history
 
+
 with gr.Blocks() as demo:
     gr.Markdown("## Canada Residential Tenancy Assistant (RAG + Mistral 7B)")
 
     chatbot = gr.Chatbot(
-        value=[(None, INTRO_MESSAGE["content"])],
-        height=500
+        value=[INTRO_TUPLE],   # must be a list of tuples!
+        height=500,
     )
 
     user_box = gr.Textbox(
@@ -254,5 +261,6 @@ with gr.Blocks() as demo:
     send_btn.click(chat_api, inputs=[user_box, chatbot], outputs=[chatbot, chatbot])
     user_box.submit(chat_api, inputs=[user_box, chatbot], outputs=[chatbot, chatbot])
 
+
 if __name__ == "__main__":
-    demo.launch()
+    demo.launch(share=True)