Update app.py

app.py

@@ -1,6 +1,7 @@
 """
 Spelling Practice – Hugging Face Space
-Multi-user safe: all mutable state lives in gr.State (one copy per browser session).
+Multi-user safe: session state is stored as a JSON string in gr.State,
+which gradio 4.40 / gradio_client 0.8 can safely introspect.
 """
 
 import os
@@ -11,7 +12,6 @@ import difflib
 import json
 import time
 import threading
-from pathlib import Path
 
 import gradio as gr
 from gtts import gTTS
@@ -23,12 +23,11 @@ try:
 except ImportError:
     _LLAMA_AVAILABLE = False
 
-# ── Model loading (shared across all users, loaded once at startup) ────────────
+# ── Shared model (loaded once, read-only during inference) ─────────────────────
 _llm = None
 _llm_lock = threading.Lock()
 
 def get_llm():
-    """Return the shared Llama instance, loading it on first call."""
     global _llm
     if _llm is not None:
         return _llm
@@ -110,17 +109,23 @@ LEVEL_LABELS = ["🟢 Beginner", "🔵 Intermediate", "🟠 Advanced", "🔴 Exp
 PASS_REQ     = 3
 
 
-# ── Per-user state ─────────────────────────────────────────────────────────────
+# ── State helpers (serialised as JSON string to avoid gradio_client schema bug) ─
 
-def fresh_state():
-    return {
+def fresh_state_str():
+    return json.dumps({
         "level":    0,
         "streak":   0,
         "sentence": "",
         "score":    0,
         "total":    0,
         "history":  [],
-    }
+    })
+
+def load(s):
+    return json.loads(s)
+
+def dump(d):
+    return json.dumps(d)
 
 
 # ── Core helpers ───────────────────────────────────────────────────────────────
@@ -216,44 +221,44 @@ def _score_info(state):
     return f"**Score: {s}/{t}** ({pct}%)"
 
 
-# ── Event handlers ─────────────────────────────────────────────────────────────
+# ── Event handlers (state_str in, state_str out) ───────────────────────────────
 
-def new_sentence(state):
+def new_sentence(state_str):
+    state = load(state_str)
     sent  = random.choice(SENTENCES[LEVELS[state["level"]]])
-    state = {**state, "sentence": sent}
+    state["sentence"] = sent
     audio = _make_audio(sent)
     hint  = "🎧 Listen carefully, then type what you heard and press **Submit**."
     if audio is None:
         hint = f"⚠️ Audio unavailable. Sentence: **{sent}**  *(type it below)*"
-    return audio, "", hint, _level_info(state), _score_info(state), state
+    return audio, "", hint, _level_info(state), _score_info(state), dump(state)
 
 
-def submit_answer(attempt, state):
+def submit_answer(attempt, state_str):
+    state = load(state_str)
     if not state.get("sentence"):
-        return "", "⚠️ Press **New Sentence** first!", _level_info(state), _score_info(state), state
+        return "", "⚠️ Press **New Sentence** first!", _level_info(state), _score_info(state), dump(state)
 
     correct = state["sentence"]
-    state   = {**state, "total": state["total"] + 1}
+    state["total"] += 1
     errors  = _find_errors(correct, attempt)
     clean_a = attempt.strip().rstrip(".").lower()
     clean_c = correct.strip().rstrip(".").lower()
 
     if not errors and clean_a == clean_c:
-        state = {**state, "score": state["score"] + 1, "streak": state["streak"] + 1}
+        state["score"]  += 1
+        state["streak"] += 1
         msg = "✅ **Correct!** Every word spelled perfectly."
         if state["streak"] >= PASS_REQ and state["level"] < len(LEVELS) - 1:
-            state = {**state, "level": state["level"] + 1, "streak": 0}
+            state["level"]  += 1
+            state["streak"]  = 0
             new_label = LEVEL_LABELS[state["level"]]
             msg += f"\n\n🎉 **Level up! You are now {new_label}.**"
     else:
-        state     = {**state, "streak": 0}
+        state["streak"] = 0
         diff_str  = _build_diff(correct, attempt)
         gemma_tip = _ask_gemma(correct, attempt, errors)
-        ai_block  = (
-            f"\n\n---\n\n**💡 Tips:**\n\n{gemma_tip}"
-            if gemma_tip
-            else ""
-        )
+        ai_block  = f"\n\n---\n\n**💡 Tips:**\n\n{gemma_tip}" if gemma_tip else ""
         msg = (
             "❌ **Your answer with corrections:**\n\n"
             + diff_str
@@ -261,29 +266,31 @@ def submit_answer(attempt, state):
             + ai_block
         )
 
-    entry = {
+    state["history"].append({
         "correct": correct,
         "attempt": attempt,
         "ok": not bool(errors) and clean_a == clean_c,
         "level": LEVELS[state["level"]],
         "ts": time.strftime("%H:%M:%S"),
-    }
-    state = {**state, "sentence": "", "history": state["history"] + [entry]}
-    return attempt, msg, _level_info(state), _score_info(state), state
+    })
+    state["sentence"] = ""
+    return attempt, msg, _level_info(state), _score_info(state), dump(state)
 
 
-def replay_audio(state):
+def replay_audio(state_str):
+    state = load(state_str)
     if state.get("sentence"):
         return _make_audio(state["sentence"])
     return None
 
 
-def reset_game(state):
-    state = fresh_state()
-    return None, "", "Game reset. Press **New Sentence** to start!", _level_info(state), _score_info(state), state
+def reset_game(state_str):
+    state = load(fresh_state_str())
+    return None, "", "Game reset. Press **New Sentence** to start!", _level_info(state), _score_info(state), fresh_state_str()
 
 
-def export_history(state):
+def export_history(state_str):
+    state   = load(state_str)
     history = state.get("history", [])
     if not history:
         return None
@@ -300,9 +307,12 @@ body { font-family: 'Segoe UI', sans-serif; }
 footer { display: none !important; }
 """
 
+_init = load(fresh_state_str())
+
 with gr.Blocks(title="Spelling Practice", css=CSS) as demo:
 
-    session = gr.State(fresh_state)
+    # gr.State holds a plain string – safe for gradio 4.40 / gradio_client 0.8
+    session = gr.State(fresh_state_str())
 
     gr.Markdown(
         "# 📝 Spelling Practice\n"
@@ -310,8 +320,8 @@ with gr.Blocks(title="Spelling Practice", css=CSS) as demo:
     )
 
     with gr.Row():
-        level_md = gr.Markdown(_level_info(fresh_state()))
-        score_md = gr.Markdown(_score_info(fresh_state()))
+        level_md = gr.Markdown(_level_info(_init))
+        score_md = gr.Markdown(_score_info(_init))
 
     with gr.Row():
         new_btn    = gr.Button("🎲 New Sentence", variant="primary")
@@ -334,12 +344,12 @@ with gr.Blocks(title="Spelling Practice", css=CSS) as demo:
 
     OUTS = [audio_out, answer_box, hint_md, level_md, score_md, session]
 
-    new_btn.click(new_sentence,    [session],              OUTS)
-    replay_btn.click(replay_audio, [session],              [audio_out])
-    submit_btn.click(submit_answer,[answer_box, session],  [answer_box, feedback, level_md, score_md, session])
+    new_btn.click(new_sentence,     [session],             OUTS)
+    replay_btn.click(replay_audio,  [session],             [audio_out])
+    submit_btn.click(submit_answer, [answer_box, session], [answer_box, feedback, level_md, score_md, session])
     answer_box.submit(submit_answer,[answer_box, session], [answer_box, feedback, level_md, score_md, session])
-    reset_btn.click(reset_game,    [session],              OUTS)
+    reset_btn.click(reset_game,     [session],             OUTS)
     export_btn.click(export_history,[session],             [history_file])
 
 if __name__ == "__main__":
-    demo.launch()
+    demo.launch(server_name="0.0.0.0", server_port=7860)