Changed how it preserves history

app.py

@@ -42,13 +42,13 @@ for message in st.session_state.messages:
 if "user_input" not in st.session_state:
     st.session_state.user_input = ""
 
-user_input = st.chat_input("Your message", key="user_input")
+user_input_displayed = st.session_state.user_input  # Capture current displayed input
 
 if st.button("Submit"):
-    if user_input:
-        st.session_state.messages.append({"role": "user", "content": user_input})
+    if user_input_displayed:  # Check if user previously entered input
+        st.session_state.messages.append({"role": "user", "content": user_input_displayed})
         with st.chat_message("user"):
-            st.markdown(user_input)
-        response = get_llama_response(user_input)
+            st.markdown(user_input_displayed)  # Display previously entered input
+        response = get_llama_response(user_input_displayed)
         with st.chat_message("assistant"):
             st.markdown(response)