Update app.py

app.py

@@ -20,9 +20,9 @@ def solve(question, history):
     messages = [
         {"role": "system", "content": "You are a helpful math tutor. Solve problems step by step, showing all working clearly."},
     ]
-    for item in history:
-        messages.append({"role": "user",      "content": item[0]})
-        messages.append({"role": "assistant", "content": item[1]})
+    for msg in history:
+        if msg["role"] in ("user", "assistant"):
+            messages.append({"role": msg["role"], "content": msg["content"]})
     messages.append({"role": "user", "content": question})
 
     text = tokenizer.apply_chat_template(
@@ -48,7 +48,10 @@ def respond(question, history):
     if not question.strip():
         return "", history
     answer = solve(question, history)
-    history = history + [[question, answer]]
+    history = history + [
+        {"role": "user",      "content": question},
+        {"role": "assistant", "content": answer},
+    ]
     return "", history
 
 # ── UI ─────────────────────────────────────────────────────
@@ -59,6 +62,9 @@ with gr.Blocks(title="Math Tutor AI") as demo:
     ---
     """)
 
+    # Store history as state
+    history_state = gr.State([])
+
     chatbot = gr.Chatbot(height=450)
 
     with gr.Row():
@@ -86,8 +92,37 @@ with gr.Blocks(title="Math Tutor AI") as demo:
 
     gr.Markdown("*Model: Qwen2.5-Math-1.5B fine-tuned on 10K math problems*")
 
-    submit.click(respond, [question, chatbot], [question, chatbot])
-    question.submit(respond, [question, chatbot], [question, chatbot])
-    clear.click(lambda: ([], ""), outputs=[chatbot, question])
+    # ── Event Handlers ─────────────────────────────────────
+    def respond_and_display(question, history):
+        if not question.strip():
+            return "", history, [[m["content"] for m in history[i:i+2]] 
+                                  for i in range(0, len(history), 2)]
+        answer = solve(question, history)
+        history = history + [
+            {"role": "user",      "content": question},
+            {"role": "assistant", "content": answer},
+        ]
+        # Convert to tuple pairs for display
+        display = []
+        for i in range(0, len(history), 2):
+            u = history[i]["content"]   if i   < len(history) else ""
+            a = history[i+1]["content"] if i+1 < len(history) else ""
+            display.append((u, a))
+        return "", history, display
+
+    def clear_all():
+        return "", [], []
+
+    submit.click(
+        respond_and_display,
+        [question, history_state],
+        [question, history_state, chatbot]
+    )
+    question.submit(
+        respond_and_display,
+        [question, history_state],
+        [question, history_state, chatbot]
+    )
+    clear.click(clear_all, outputs=[question, history_state, chatbot])
 
 demo.launch(theme=gr.themes.Soft())