update logic flow of app to include start button

app.py

@@ -6,7 +6,6 @@ import gradio as gr
 from datasets import load_dataset, Dataset
 from huggingface_hub import whoami
 
-
 EXAM_DATASET_ID = os.getenv("EXAM_DATASET_ID") or "agents-course/unit_1_quiz"
 EXAM_MAX_QUESTIONS = os.getenv("EXAM_MAX_QUESTIONS") or 10
 EXAM_PASSING_SCORE = os.getenv("EXAM_PASSING_SCORE") or 0.7
@@ -24,14 +23,37 @@ if EXAM_MAX_QUESTIONS:
 
 def on_user_logged_in(token: gr.OAuthToken | None):
     """
-    If the user has a valid token, hide the login button and show the Start button.
-    Otherwise, keep the login button visible, hide Start.
+    If the user has a valid token, show Start button.
+    Otherwise, keep the login button visible.
     """
     if token is not None:
-        return gr.update(visible=False), gr.update(visible=False)
+        return [
+            gr.update(visible=False),  # login button visibility
+            gr.update(visible=True),  # start button visibility
+            gr.update(visible=False),  # next button visibility
+            gr.update(visible=False),  # submit button visibility
+            "",  # question text
+            [],  # radio choices (empty list = no choices)
+            "Click 'Start' to begin the quiz",  # status message
+            0,  # question_idx
+            [],  # user_answers
+            "",  # final_markdown content
+            token,  # user token
+        ]
     else:
-        # Not logged in, keep the login visible, hide Start
-        return gr.update(visible=True), gr.update(visible=False)
+        return [
+            gr.update(visible=True),  # login button visibility
+            gr.update(visible=False),  # start button visibility
+            gr.update(visible=False),  # next button visibility
+            gr.update(visible=False),  # submit button visibility
+            "",  # question text
+            [],  # radio choices
+            "",  # status message
+            0,  # question_idx
+            [],  # user_answers
+            "",  # final_markdown content
+            None,  # no token
+        ]
 
 
 def push_results_to_hub(user_answers, token: gr.OAuthToken | None):
@@ -74,36 +96,24 @@ def push_results_to_hub(user_answers, token: gr.OAuthToken | None):
 
 def handle_quiz(question_idx, user_answers, selected_answer, is_start):
     """
-    A single function that handles both 'Start' and 'Next' logic:
-      - If is_start=True, skip storing an answer and show the first question.
-      - Otherwise, store the last answer and move on.
-      - If we've reached the end, display results.
+    Handle quiz state transitions and store answers
     """
-    # Hide the start button once the first question is shown
-    start_btn_update = gr.update(visible=False) if is_start else None
-
-    # If this is the first time (start=True), begin at question_idx=0
-    if is_start:
-        question_idx = 0
-    else:
-        # If not the very first question, store the user's last selection
-        if question_idx < len(quiz_data):
-            current_q = quiz_data[question_idx]
-            correct_reference = current_q["correct_answer"]
-            correct_reference = f"answer_{correct_reference}".lower()
-            is_correct = selected_answer == current_q[correct_reference]
-            user_answers.append(
-                {
-                    "question": current_q["question"],
-                    "selected_answer": selected_answer,
-                    "correct_answer": current_q[correct_reference],
-                    "is_correct": is_correct,
-                    "correct_reference": correct_reference,
-                }
-            )
+    if not is_start and question_idx < len(quiz_data):
+        current_q = quiz_data[question_idx]
+        correct_reference = current_q["correct_answer"]
+        correct_reference = f"answer_{correct_reference}".lower()
+        is_correct = selected_answer == current_q[correct_reference]
+        user_answers.append(
+            {
+                "question": current_q["question"],
+                "selected_answer": selected_answer,
+                "correct_answer": current_q[correct_reference],
+                "is_correct": is_correct,
+                "correct_reference": correct_reference,
+            }
+        )
         question_idx += 1
 
-    # If we've reached the end, show final results
     if question_idx >= len(quiz_data):
         correct_count = sum(1 for answer in user_answers if answer["is_correct"])
         grade = correct_count / len(user_answers)
@@ -112,37 +122,35 @@ def handle_quiz(question_idx, user_answers, selected_answer, is_start):
             f"Your score: {grade:.1%}\n"
             f"Passing score: {float(EXAM_PASSING_SCORE):.1%}\n\n"
         )
-        return (
-            "",  # question_text becomes blank
-            gr.update(choices=[], visible=False),
+        return [
+            "",  # question_text
+            gr.update(choices=[], visible=False),  # hide radio choices
             f"{'✅ Passed!' if grade >= float(EXAM_PASSING_SCORE) else '❌ Did not pass'}",
             question_idx,
             user_answers,
-            start_btn_update,
-            gr.update(value=results_text, visible=True),  # show final_markdown
-        )
-    else:
-        # Otherwise, show the next question
-        q = quiz_data[question_idx]
-        updated_question = f"## Question {question_idx + 1} \n### {q['question']}"
-        return (
-            updated_question,
-            gr.update(
-                choices=[
-                    q["answer_a"],
-                    q["answer_b"],
-                    q["answer_c"],
-                    q["answer_d"],
-                ],
-                value=None,
-                visible=True,
-            ),
-            "Select an answer and click 'Next' to continue.",
-            question_idx,
-            user_answers,
-            start_btn_update,
-            gr.update(visible=False),  # Hide final_markdown for now
-        )
+            gr.update(visible=False),  # start button visibility
+            gr.update(visible=False),  # next button visibility
+            gr.update(visible=True),  # submit button visibility
+            results_text,  # final results text
+        ]
+
+    # Show next question
+    q = quiz_data[question_idx]
+    return [
+        f"## Question {question_idx + 1} \n### {q['question']}",  # question text
+        gr.update(  # properly update radio choices
+            choices=[q["answer_a"], q["answer_b"], q["answer_c"], q["answer_d"]],
+            value=None,
+            visible=True,
+        ),
+        "Select an answer and click 'Next' to continue.",
+        question_idx,
+        user_answers,
+        gr.update(visible=False),  # start button visibility
+        gr.update(visible=True),  # next button visibility
+        gr.update(visible=False),  # submit button visibility
+        "",  # clear final markdown
+    ]
 
 
 def success_message(response):
@@ -152,47 +160,58 @@ def success_message(response):
 
 with gr.Blocks() as demo:
     demo.title = f"Dataset Quiz for {EXAM_DATASET_ID}"
+
     # State variables
     question_idx = gr.State(value=0)
     user_answers = gr.State(value=[])
+    user_token = gr.State(value=None)
 
     with gr.Row(variant="compact"):
         gr.Markdown(f"## Welcome to the {EXAM_DATASET_ID} Quiz")
+
     with gr.Row(variant="compact"):
         gr.Markdown(
             "Log in first, then click 'Start' to begin. Answer each question, click 'Next', and finally click 'Submit' to publish your results to the Hugging Face Hub."
         )
-    # We display question text with Markdown
-    with gr.Row(
-        variant="panel",
-    ):
+
+    with gr.Row(variant="panel"):
         question_text = gr.Markdown("")
         radio_choices = gr.Radio(
-            choices=[], visible=False, label="Your Answer", scale=1.5
+            choices=[], label="Your Answer", scale=1.5, visible=False
         )
 
     with gr.Row(variant="compact"):
         status_text = gr.Markdown("")
+        final_markdown = gr.Markdown("")
 
     with gr.Row(variant="compact"):
-        # Final results after all questions are done
-        final_markdown = gr.Markdown("", visible=False)
-
-        next_btn = gr.Button("Next ⏭️")
-        submit_btn = gr.Button("Submit ✅")
-
-    with gr.Row(variant="compact"):
-        login_btn = gr.LoginButton()
-        # We'll hide the Start button until user logs in
-        start_btn = gr.Button("Start", visible=False)
-
-    # Use click() instead of login()
-    login_btn.click(fn=on_user_logged_in, inputs=None, outputs=[login_btn, start_btn])
+        login_btn = gr.LoginButton(visible=True)
+        start_btn = gr.Button("Start ⏭️", visible=True)
+        next_btn = gr.Button("Next ⏭️", visible=False)
+        submit_btn = gr.Button("Submit ✅", visible=False)
+
+    # Wire up the event handlers
+    login_btn.click(
+        fn=on_user_logged_in,
+        inputs=None,
+        outputs=[
+            login_btn,
+            start_btn,
+            next_btn,
+            submit_btn,
+            question_text,
+            radio_choices,
+            status_text,
+            question_idx,
+            user_answers,
+            final_markdown,
+            user_token,
+        ],
+    )
 
-    # Click "Start" => show first question, hide Start button
     start_btn.click(
         fn=handle_quiz,
-        inputs=[question_idx, user_answers, radio_choices, gr.State(True)],
+        inputs=[question_idx, user_answers, gr.State(""), gr.State(True)],
         outputs=[
             question_text,
             radio_choices,
@@ -200,11 +219,12 @@ with gr.Blocks() as demo:
             question_idx,
             user_answers,
             start_btn,
+            next_btn,
+            submit_btn,
             final_markdown,
         ],
     )
 
-    # Click "Next" => store selection, move on
     next_btn.click(
         fn=handle_quiz,
         inputs=[question_idx, user_answers, radio_choices, gr.State(False)],
@@ -215,13 +235,14 @@ with gr.Blocks() as demo:
             question_idx,
             user_answers,
             start_btn,
+            next_btn,
+            submit_btn,
             final_markdown,
         ],
     )
 
     submit_btn.click(fn=push_results_to_hub, inputs=[user_answers])
 
-
 if __name__ == "__main__":
     # Note: If testing locally, you'll need to run `huggingface-cli login` or set HF_TOKEN
     # environment variable for the login to work locally.