prevent podcast without context

stream_app/chat.py

@@ -77,6 +77,11 @@ def chat_sidebar(session_id):
                 instructions = st.text_area(
                     "Instructions", value=selected_template.user_instructions
                 )
+                if len(context.get("note", [])) + len(context.get("source", [])) == 0:
+                    st.warning(
+                        "No notes or sources found in context. You don't want a boring podcast, right? So, add some context first."
+                    )
+                else:
                     if st.button("Generate"):
                         with st.spinner("Go grab a coffee, almost there..."):
                             selected_template.generate_episode(