Save generated files to sessions; attachments feature

Implement persistent attachments for course creator: update db.py to include attachments table and add helpers (add_attachment, list_attachments). Modify app.py to import new helpers, add attachments output component, and update session loading and finalize/generate functions to store generated documents and zip packages in the database and update attachments display. Now each chat session lists its saved files and caches resources.

app.py

@@ -21,6 +21,8 @@ from db import (
     list_chats,
     rename_chat,
     delete_chat,
+    add_attachment,
+    list_attachments,
 )
 
 # Import the docx utility to generate Word documents for course outlines.
@@ -437,31 +439,58 @@ def finalize_and_doc(chat_history, chat_pairs, sources, plan, chat_key):
         with open(tmp_path, "w") as f:
             f.write(err_msg)
         doc_path = tmp_path
+    # Record the generated document as an attachment tied to this chat
+    if chat_key:
+        try:
+            add_attachment(chat_key, doc_path, os.path.basename(doc_path))
+        except Exception:
+            pass
+    # Fetch updated attachment list
+    attachments = []
+    if chat_key:
+        try:
+            attachment_records = list_attachments(chat_key)
+            attachments = [att.get("file_path") for att in attachment_records if att.get("file_path")]
+        except Exception:
+            attachments = []
     # Update plan state
     plan = plan_text
-    return plan_text, chat_history, chat_pairs, sources, plan, doc_path
+    return plan_text, chat_history, chat_pairs, sources, plan, doc_path, attachments
 
-def generate_package(plan, sources):
-    """Generate the final course package zip file."""
-    if plan is None or plan == "":
-        # fallback: create a minimal plan if none exists
+def generate_package(plan, sources, chat_key):
+    """Generate the final course package zip file and record it as an attachment."""
+    # Fallback: create a minimal plan if none exists
+    if not plan:
         plan = "Course plan is empty."
     if sources is None:
         sources = []
     try:
         zip_path = generate_course_zip(plan, sources)
-        return zip_path
     except Exception as e:
-        # On error, return a message as a text file inside an in-memory file path to avoid raising exceptions in Gradio
+        # On error, return a message as a text file inside an in-memory file path
         err_msg = (
             "An error occurred while generating the course package. Please check your API keys or input.\n"
             f"(Error: {e})"
         )
-        # Create a text file to return with the error message
         tmp_path = "/tmp/error.txt"
         with open(tmp_path, "w") as f:
             f.write(err_msg)
-        return tmp_path
+        zip_path = tmp_path
+    # Record the generated zip as an attachment
+    if chat_key:
+        try:
+            add_attachment(chat_key, zip_path, os.path.basename(zip_path))
+        except Exception:
+            pass
+    # Fetch updated attachment list
+    attachments = []
+    if chat_key:
+        try:
+            records = list_attachments(chat_key)
+            attachments = [att.get("file_path") for att in records if att.get("file_path")]
+        except Exception:
+            attachments = []
+    return zip_path, attachments
 
 with gr.Blocks() as demo:
     gr.Markdown(
@@ -503,6 +532,9 @@ Chat with the assistant to brainstorm your course idea. Use the panel on the lef
             finalize_btn = gr.Button("Finalize Outline")
             plan_output = gr.Textbox(label="Course outline", interactive=False)
             doc_output = gr.File(label="Course outline (Word)")
+            # Display any files generated during the chat session. This component
+            # will show multiple attachments and allow downloading them.
+            attachments_output = gr.File(label="Attachments", file_count="multiple")
             generate_btn = gr.Button("Generate Course Package")
             file_output = gr.File(label="course.zip")
 
@@ -572,7 +604,13 @@ Chat with the assistant to brainstorm your course idea. Use the panel on the lef
                     buffer[1] = content
                     pairs.append(tuple(buffer))
                     buffer = []
-        return pairs, history, pairs, [], "", {}
+        # Load any previously generated attachments for this chat
+        try:
+            attachment_records = list_attachments(selected_key)
+            attachments = [att.get("file_path") for att in attachment_records if att.get("file_path")]
+        except Exception:
+            attachments = []
+        return pairs, history, pairs, [], "", {}, attachments
 
     # Create a new chat session and return the new key
     def handle_new_chat():
@@ -601,11 +639,11 @@ Chat with the assistant to brainstorm your course idea. Use the panel on the lef
         None,
         [session_picker],
     )
-    # When a session is selected, load it
+    # When a session is selected, load it along with its attachments
     session_picker.change(
         load_session,
         inputs=session_picker,
-        outputs=[chatbot, state_chat_history, state_chat_pairs, state_sources, state_plan, state_resource_cache],
+        outputs=[chatbot, state_chat_history, state_chat_pairs, state_sources, state_plan, state_resource_cache, attachments_output],
     )
     # New chat button
     new_chat_btn.click(
@@ -619,7 +657,7 @@ Chat with the assistant to brainstorm your course idea. Use the panel on the lef
     ).then(
         load_session,
         inputs=state_chat_key,
-        outputs=[chatbot, state_chat_history, state_chat_pairs, state_sources, state_plan, state_resource_cache],
+        outputs=[chatbot, state_chat_history, state_chat_pairs, state_sources, state_plan, state_resource_cache, attachments_output],
     )
     # Rename button
     rename_btn.click(
@@ -643,7 +681,7 @@ Chat with the assistant to brainstorm your course idea. Use the panel on the lef
     ).then(
         load_session,
         inputs=state_chat_key,
-        outputs=[chatbot, state_chat_history, state_chat_pairs, state_sources, state_plan, state_resource_cache],
+        outputs=[chatbot, state_chat_history, state_chat_pairs, state_sources, state_plan, state_resource_cache, attachments_output],
     )
     # Chat submission: include chat_key for persistence
     msg_input.submit(
@@ -651,16 +689,16 @@ Chat with the assistant to brainstorm your course idea. Use the panel on the lef
         inputs=[msg_input, state_chat_history, state_chat_pairs, state_sources, state_plan, state_resource_cache, state_chat_key],
         outputs=[chatbot, state_chat_history, state_chat_pairs, state_sources, state_plan, state_resource_cache],
     )
-    # Finalise outline and produce Word doc
+    # Finalise outline and produce Word doc, recording the doc as an attachment
     finalize_btn.click(
         finalize_and_doc,
         inputs=[state_chat_history, state_chat_pairs, state_sources, state_plan, state_chat_key],
-        outputs=[plan_output, state_chat_history, state_chat_pairs, state_sources, state_plan, doc_output],
+        outputs=[plan_output, state_chat_history, state_chat_pairs, state_sources, state_plan, doc_output, attachments_output],
     )
-    # Generate course package (zip)
+    # Generate course package (zip) and record it as an attachment
     generate_btn.click(
         generate_package,
-        inputs=[state_plan, state_sources],
-        outputs=file_output,
+        inputs=[state_plan, state_sources, state_chat_key],
+        outputs=[file_output, attachments_output],
     )
     demo.launch()

db.py

@@ -52,6 +52,20 @@ def _ensure_db():
             created_at INTEGER,
             FOREIGN KEY(chat_key) REFERENCES chats(chat_key)
         );
+
+        -- Table to track files generated during chat sessions. Each record stores
+        -- the chat_key to which the file belongs, the original file name,
+        -- the absolute file path on disk, and the timestamp when it was
+        -- created. These attachments allow the UI to show downloadable files
+        -- generated in earlier chat interactions.
+        CREATE TABLE IF NOT EXISTS attachments (
+            id INTEGER PRIMARY KEY,
+            chat_key TEXT,
+            file_name TEXT,
+            file_path TEXT,
+            created_at INTEGER,
+            FOREIGN KEY(chat_key) REFERENCES chats(chat_key)
+        );
         """
     )
     conn.commit()
@@ -207,4 +221,46 @@ def delete_chat(chat_key: str) -> None:
     """
     with get_conn() as conn:
         conn.execute("DELETE FROM messages WHERE chat_key=?", (chat_key,))
-        conn.execute("DELETE FROM chats WHERE chat_key=?", (chat_key,))
+        conn.execute("DELETE FROM chats WHERE chat_key=?", (chat_key,))
+
+# ---------------------------------------------------------------------------
+# Attachment management helpers
+#
+# These helpers allow the app to record files generated during chat sessions
+# (such as outlines, scripts, zip packages) so they persist and can be
+# downloaded later. Each attachment is tied to a chat via its chat_key.
+
+def add_attachment(chat_key: str, file_path: str, file_name: str) -> None:
+    """Store a new file attachment for a chat.
+
+    Args:
+        chat_key: The unique chat key that the file belongs to.
+        file_path: The absolute path to the file on disk.
+        file_name: The base name of the file (for display).
+    """
+    now = int(time.time())
+    with get_conn() as conn:
+        conn.execute(
+            "INSERT INTO attachments (chat_key, file_name, file_path, created_at) VALUES (?, ?, ?, ?)",
+            (chat_key, file_name, file_path, now),
+        )
+
+
+def list_attachments(chat_key: str) -> list[dict]:
+    """List all attachments for a given chat.
+
+    Args:
+        chat_key: The chat to list files for.
+
+    Returns:
+        A list of dictionaries, each with keys 'file_name', 'file_path' and 'created_at'.
+    """
+    with get_conn() as conn:
+        rows = conn.execute(
+            "SELECT file_name, file_path, created_at FROM attachments WHERE chat_key=? ORDER BY created_at ASC",
+            (chat_key,),
+        ).fetchall()
+    return [
+        {"file_name": fname, "file_path": fpath, "created_at": ts}
+        for fname, fpath, ts in rows
+    ]