Fix NameError in navigation logic

app.py

@@ -793,23 +793,28 @@ with gr.Blocks(title="AnatomyBot - MBBS Anatomy Tutor") as demo:
         # Display student name
         student_name_display = gr.Markdown("")
         
-        # Tabs are inside main_app so they're hidden initially
-        with gr.Tabs(elem_id="main_tabs") as tabs:
-            # LEARNING MODE TAB
-            with gr.Tab("📚 Learning Mode", elem_id="tab_learning"):
-                # Search and examples at the top
-                with gr.Row():
-                    query_input = gr.Textbox(
-                        label="Ask an Anatomy Question",
-                        placeholder="e.g., Show me the Circle of Willis",
-                        lines=2
-                    )
-                
-                # Examples
-                gr.Examples(
-                    examples=[
-                        ["Show me the Circle of Willis"],
-                        ["Brachial plexus anatomy"],
+        # Custom Navigation Bar
+        with gr.Row(elem_id="nav_bar"):
+            nav_learning_btn = gr.Button("📚 Learning Mode", variant="primary", scale=1)
+            nav_viva_btn = gr.Button("🎯 VIVA Training Mode", variant="secondary", scale=1)
+            nav_book_btn = gr.Button("📖 Book Learning Mode", variant="secondary", scale=1)
+            nav_admin_btn = gr.Button("🔐 Admin Panel", variant="secondary", scale=1)
+
+        # LEARNING MODE COLUMN
+        with gr.Column(visible=True, elem_id="learning_col") as learning_col:
+            # Search and examples at the top
+            with gr.Row():
+                query_input = gr.Textbox(
+                    label="Ask an Anatomy Question",
+                    placeholder="e.g., Show me the Circle of Willis",
+                    lines=2
+                )
+            
+            # Examples
+            gr.Examples(
+                examples=[
+                    ["Show me the Circle of Willis"],
+                    ["Brachial plexus anatomy"],
                     ["Carpal bones arrangement"],
                     ["Layers of the scalp"],
                     ["Anatomy of the heart chambers"],
@@ -841,17 +846,17 @@ with gr.Blocks(title="AnatomyBot - MBBS Anatomy Tutor") as demo:
                 with gr.Column(scale=1):
                     image_output = gr.Image(label="🖼️ Anatomy Diagram", type="pil")
         
-        # VIVA MODE TAB (Defined before Book Mode to allow component access)
-            with gr.Tab("🎯 VIVA Training Mode", elem_id="tab_viva") as viva_tab:
-                viva_status = gr.Markdown("Click 'Start VIVA Training' from Learning Mode after studying a topic!")
+        # VIVA MODE COLUMN
+        with gr.Column(visible=False, elem_id="viva_col") as viva_col:
+            viva_status = gr.Markdown("Click 'Start VIVA Training' from Learning Mode after studying a topic!")
             
-                # Additional greeting component (initially hidden)
-                viva_greeting = gr.Markdown("", visible=False)
+            # Additional greeting component (initially hidden)
+            viva_greeting = gr.Markdown("", visible=False)
             
-                with gr.Column(visible=False) as viva_container:
-                    with gr.Row():
-                        with gr.Column(scale=1):
-                            viva_image = gr.Image(label="Reference Image", type="pil", interactive=False)
+            with gr.Column(visible=False) as viva_container:
+                with gr.Row():
+                    with gr.Column(scale=1):
+                        viva_image = gr.Image(label="Reference Image", type="pil", interactive=False)
                     
                         with gr.Column(scale=2):
                             current_question_display = gr.Markdown("### Question will appear here")
@@ -870,132 +875,115 @@ with gr.Blocks(title="AnatomyBot - MBBS Anatomy Tutor") as demo:
                         
                             feedback_display = gr.Markdown("Feedback will appear here after you submit your answer")
 
-            # BOOK LEARNING MODE TAB
-            with gr.Tab("📖 Book Learning Mode", elem_id="tab_book") as book_tab:
-                # Upload PDF
-                pdf_upload = gr.File(label="Upload Anatomy Textbook (PDF)", file_types=[".pdf"], type="binary")
-                upload_status = gr.Markdown()
+        # BOOK LEARNING MODE COLUMN
+        with gr.Column(visible=False, elem_id="book_col") as book_col:
+            # Upload PDF
+            pdf_upload = gr.File(label="Upload Anatomy Textbook (PDF)", file_types=[".pdf"], type="binary")
+            upload_status = gr.Markdown()
             
-                # State to hold extracted images, captions, and text
-                book_images_state = gr.State([])
-                page_captions_state = gr.State([])
-                page_texts_state = gr.State([])
+            # State to hold extracted images, captions, and text
+            book_images_state = gr.State([])
+            page_captions_state = gr.State([])
+            page_texts_state = gr.State([])
             
-                # Dropdown to select a page after processing
-                page_dropdown = gr.Dropdown(label="Select Page", choices=[], interactive=False)
+            # Dropdown to select a page after processing
+            page_dropdown = gr.Dropdown(label="Select Page", choices=[], interactive=False)
             
-                # Display selected page image
-                selected_page_image = gr.Image(label="Selected Page", type="pil")
+            # Display selected page image
+            selected_page_image = gr.Image(label="Selected Page", type="pil")
             
-                # Analysis output
-                analysis_output = gr.Markdown(label="Page Analysis")
+            # Analysis output
+            analysis_output = gr.Markdown(label="Page Analysis")
             
-                # Button to start VIVA from this page
-                start_viva_book_btn = gr.Button("🎯 Start VIVA Training from this Page", variant="primary", visible=False)
+            # Button to start VIVA from this page
+            start_viva_book_btn = gr.Button("🎯 Start VIVA Training from this Page", variant="primary", visible=False)
             
-                # Process upload
-                def handle_book_upload(pdf_bytes):
-                    extracted_data, status_msg = process_uploaded_book(pdf_bytes)
-                    if not extracted_data:
-                        # No data extracted
-                        return [], status_msg, [], [], gr.update(choices=[], interactive=False), None, ""
+            # Process upload
+            def handle_book_upload(pdf_bytes):
+                extracted_data, status_msg = process_uploaded_book(pdf_bytes)
+                if not extracted_data:
+                    # No data extracted
+                    return [], status_msg, [], [], gr.update(choices=[], interactive=False), None, ""
                 
-                    # Separate images, captions, and text
-                    img_list = [item[0] for item in extracted_data]
-                    caps = [item[1] for item in extracted_data]
-                    texts = [item[2] for item in extracted_data]
+                # Separate images, captions, and text
+                img_list = [item[0] for item in extracted_data]
+                caps = [item[1] for item in extracted_data]
+                texts = [item[2] for item in extracted_data]
                 
-                    # Update dropdown with captions and enable it
-                    dropdown_update = gr.update(choices=caps, interactive=True)
-                    return img_list, status_msg, caps, texts, dropdown_update, None, ""
+                # Update dropdown with captions and enable it
+                dropdown_update = gr.update(choices=caps, interactive=True)
+                return img_list, status_msg, caps, texts, dropdown_update, None, ""
             
-                pdf_upload.upload(
-                    fn=handle_book_upload,
-                    inputs=[pdf_upload],
-                    outputs=[book_images_state, upload_status, page_captions_state, page_texts_state, page_dropdown, selected_page_image, analysis_output]
-                )
+            pdf_upload.upload(
+                fn=handle_book_upload,
+                inputs=[pdf_upload],
+                outputs=[book_images_state, upload_status, page_captions_state, page_texts_state, page_dropdown, selected_page_image, analysis_output]
+            )
             
-                # When a page is selected, show image and analysis
-                def show_page_analysis(selected_caption, images, captions, texts):
-                    if not selected_caption:
-                        return None, ""
-                    # Find index
-                    try:
-                        idx = captions.index(selected_caption)
-                    except ValueError:
-                        return None, ""
+            # When a page is selected, show image and analysis
+            def show_page_analysis(selected_caption, images, captions, texts):
+                if not selected_caption:
+                    return None, ""
+                # Find index
+                try:
+                    idx = captions.index(selected_caption)
+                except ValueError:
+                    return None, ""
                 
-                    img = images[idx]
-                    text = texts[idx] if idx < len(texts) else ""
+                img = images[idx]
+                text = texts[idx] if idx < len(texts) else ""
                 
-                    analysis = analyze_book_image(img, selected_caption, text)
+                analysis = analyze_book_image(img, selected_caption, text)
                 
-                    # Construct a topic string for VIVA
-                    viva_topic = f"Anatomy of {selected_caption} (from textbook)"
+                # Construct a topic string for VIVA
+                viva_topic = f"Anatomy of {selected_caption} (from textbook)"
                 
-                    return img, analysis, viva_topic, gr.update(visible=True)
-            
-                # Hidden state to store current page topic for VIVA
-                current_book_topic = gr.State("")
+                return img, analysis, viva_topic, gr.update(visible=True)
             
-                page_dropdown.change(
-                    fn=show_page_analysis, 
-                    inputs=[page_dropdown, book_images_state, page_captions_state, page_texts_state], 
-                    outputs=[selected_page_image, analysis_output, current_book_topic, start_viva_book_btn]
-                )
+            # Hidden state to store current page topic for VIVA
+            current_book_topic = gr.State("")
             
-                # Start VIVA from Book Mode - Use pre-collected name
-            start_viva_book_btn.click(
-                fn=lambda name, topic, image: start_viva_with_name(name, topic, image),
-                inputs=[student_name_state, current_book_topic, selected_page_image],
-                outputs=[
-                    viva_container, viva_status, viva_image,
-                    current_question_display, hint_display,
-                    student_answer, feedback_display, submit_answer_btn,
-                    viva_questions_state,
-                    question_audio, viva_greeting, student_name_state
-                ]
-            ).then(
-                fn=lambda: gr.update(selected=1),  # Switch to VIVA tab
-                outputs=[tabs]
-            ).then(
-                fn=lambda: 0,
-                outputs=[current_question_idx]
+            page_dropdown.change(
+                fn=show_page_analysis, 
+                inputs=[page_dropdown, book_images_state, page_captions_state, page_texts_state], 
+                outputs=[selected_page_image, analysis_output, current_book_topic, start_viva_book_btn]
             )
+            
+            # Start VIVA from Book Mode handler moved to end of file to resolve NameError
         
-            # ADMIN PANEL TAB
-            with gr.Tab("🔐 Admin Panel", elem_id="tab_admin") as admin_tab:
-                gr.Markdown("## Admin Panel - Student Database")
-                gr.Markdown("Enter the admin password to view registered students.")
+        # ADMIN PANEL COLUMN
+        with gr.Column(visible=False, elem_id="admin_col") as admin_col:
+            gr.Markdown("## Admin Panel - Student Database")
+            gr.Markdown("Enter the admin password to view registered students.")
             
-                # Password input
-                with gr.Row():
-                    admin_password_input = gr.Textbox(
-                        label="Admin Password",
-                        placeholder="Enter admin password",
-                        type="password",
-                        scale=2
-                    )
-                    admin_login_btn = gr.Button("🔓 Login", variant="primary", scale=1)
+            # Password input
+            with gr.Row():
+                admin_password_input = gr.Textbox(
+                    label="Admin Password",
+                    placeholder="Enter admin password",
+                    type="password",
+                    scale=2
+                )
+                admin_login_btn = gr.Button("🔓 Login", variant="primary", scale=1)
             
-                admin_status = gr.Markdown("")
+            admin_status = gr.Markdown("")
             
-                # Admin content (hidden until authenticated)
-                with gr.Column(visible=False) as admin_content:
-                    gr.Markdown("### 📊 Registered Students")
+            # Admin content (hidden until authenticated)
+            with gr.Column(visible=False) as admin_content:
+                gr.Markdown("### 📊 Registered Students")
                 
-                    admin_stats = gr.Markdown("")
+                admin_stats = gr.Markdown("")
                 
-                    with gr.Row():
-                        refresh_btn = gr.Button("🔄 Refresh Data", variant="secondary")
-                        logout_btn = gr.Button("🚪 Logout", variant="secondary")
+                with gr.Row():
+                    refresh_btn = gr.Button("🔄 Refresh Data", variant="secondary")
+                    logout_btn = gr.Button("🚪 Logout", variant="secondary")
                 
-                    students_table = gr.Dataframe(
-                        headers=["ID", "Name", "Medical School", "Year", "Registration Date"],
-                        label="Students Database",
-                        interactive=False,
-                        wrap=True
-                    )
+                students_table = gr.Dataframe(
+                    headers=["ID", "Name", "Medical School", "Year", "Registration Date"],
+                    label="Students Database",
+                    interactive=False,
+                    wrap=True
+                )
     
     # Registration Modal Popup (shown on first load)
     with gr.Column(visible=True, elem_id="registration_modal") as registration_modal:
@@ -1035,6 +1023,58 @@ with gr.Blocks(title="AnatomyBot - MBBS Anatomy Tutor") as demo:
     
     # Event Handlers
     
+    # Navigation Logic
+    def navigate(nav_target):
+        """Handle navigation between views."""
+        # Returns: learning_col, viva_col, book_col, admin_col
+        # Also returns button variants: learning_btn, viva_btn, book_btn, admin_btn
+        
+        if nav_target == "learning":
+            return (
+                gr.update(visible=True), gr.update(visible=False), gr.update(visible=False), gr.update(visible=False),
+                gr.update(variant="primary"), gr.update(variant="secondary"), gr.update(variant="secondary"), gr.update(variant="secondary")
+            )
+        elif nav_target == "viva":
+            return (
+                gr.update(visible=False), gr.update(visible=True), gr.update(visible=False), gr.update(visible=False),
+                gr.update(variant="secondary"), gr.update(variant="primary"), gr.update(variant="secondary"), gr.update(variant="secondary")
+            )
+        elif nav_target == "book":
+            return (
+                gr.update(visible=False), gr.update(visible=False), gr.update(visible=True), gr.update(visible=False),
+                gr.update(variant="secondary"), gr.update(variant="secondary"), gr.update(variant="primary"), gr.update(variant="secondary")
+            )
+        elif nav_target == "admin":
+            return (
+                gr.update(visible=False), gr.update(visible=False), gr.update(visible=False), gr.update(visible=True),
+                gr.update(variant="secondary"), gr.update(variant="secondary"), gr.update(variant="secondary"), gr.update(variant="primary")
+            )
+        return (
+            gr.update(visible=True), gr.update(visible=False), gr.update(visible=False), gr.update(visible=False),
+            gr.update(variant="primary"), gr.update(variant="secondary"), gr.update(variant="secondary"), gr.update(variant="secondary")
+        )
+
+    # Bind Navigation Buttons
+    nav_learning_btn.click(
+        fn=lambda: navigate("learning"),
+        outputs=[learning_col, viva_col, book_col, admin_col, nav_learning_btn, nav_viva_btn, nav_book_btn, nav_admin_btn]
+    )
+    
+    nav_viva_btn.click(
+        fn=lambda: navigate("viva"),
+        outputs=[learning_col, viva_col, book_col, admin_col, nav_learning_btn, nav_viva_btn, nav_book_btn, nav_admin_btn]
+    )
+    
+    nav_book_btn.click(
+        fn=lambda: navigate("book"),
+        outputs=[learning_col, viva_col, book_col, admin_col, nav_learning_btn, nav_viva_btn, nav_book_btn, nav_admin_btn]
+    )
+    
+    nav_admin_btn.click(
+        fn=lambda: navigate("admin"),
+        outputs=[learning_col, viva_col, book_col, admin_col, nav_learning_btn, nav_viva_btn, nav_book_btn, nav_admin_btn]
+    )
+
     # Welcome Screen Handler (now for modal)
     def handle_modal_submit(name, medical_school, year):
         """Handle registration modal submission."""
@@ -1099,8 +1139,11 @@ with gr.Blocks(title="AnatomyBot - MBBS Anatomy Tutor") as demo:
             student_name_state  # Return student name (unchanged)
         ]
     ).then(
-        fn=lambda: gr.update(selected=1),  # Switch to VIVA tab
-        outputs=[tabs]
+        fn=lambda: (gr.update(visible=False), gr.update(visible=True), gr.update(visible=False), gr.update(visible=False)),
+        outputs=[learning_col, viva_col, book_col, admin_col]
+    ).then(
+        fn=lambda: (gr.update(variant="secondary"), gr.update(variant="primary"), gr.update(variant="secondary"), gr.update(variant="secondary")),
+        outputs=[nav_learning_btn, nav_viva_btn, nav_book_btn, nav_admin_btn]
     ).then(
         fn=lambda: gr.update(value="🎯 Start VIVA Training", interactive=True),  # Reset button
         outputs=[start_viva_btn]
@@ -1180,6 +1223,28 @@ with gr.Blocks(title="AnatomyBot - MBBS Anatomy Tutor") as demo:
         outputs=[admin_stats, students_table]
     )
 
+    # Start VIVA from Book Mode - Use pre-collected name (Moved here to ensure all columns are defined)
+    start_viva_book_btn.click(
+        fn=lambda name, topic, image: start_viva_with_name(name, topic, image),
+        inputs=[student_name_state, current_book_topic, selected_page_image],
+        outputs=[
+            viva_container, viva_status, viva_image,
+            current_question_display, hint_display,
+            student_answer, feedback_display, submit_answer_btn,
+            viva_questions_state,
+            question_audio, viva_greeting, student_name_state
+        ]
+    ).then(
+        fn=lambda: (gr.update(visible=False), gr.update(visible=True), gr.update(visible=False), gr.update(visible=False)),
+        outputs=[learning_col, viva_col, book_col, admin_col]
+    ).then(
+        fn=lambda: (gr.update(variant="secondary"), gr.update(variant="primary"), gr.update(variant="secondary"), gr.update(variant="secondary")),
+        outputs=[nav_learning_btn, nav_viva_btn, nav_book_btn, nav_admin_btn]
+    ).then(
+        fn=lambda: 0,
+        outputs=[current_question_idx]
+    )
+
 if __name__ == "__main__":
     # Check if API keys are configured
     if not SERPAPI_KEY or SERPAPI_KEY == "your_serpapi_key_here":