# Course Builder Auto-Save Analysis

## Current Status: ✅ NO AUTOMATIC SAVING

The `course_builder.php` page does **NOT** have automatic saving or auto-updating on page refresh. All data persistence is controlled by explicit user actions (clicking submit buttons on form modals).

## How It Works

### Current Implementation: Form-Based Persistence

All data changes trigger through traditional HTML forms with explicit submit buttons:

```
User Action → Modal Form → Submit Button → POST Request → Database Update
```

### POST Handlers (All Explicit)

1. **add_lesson** - Creates new lesson (Submit button in Add Lesson Modal)
2. **add_module** - Creates new module (Submit button in Add Module Modal)
3. **add_topic** - Creates new topic (Submit button in Add Topic Modal)
4. **update_course** - Updates course details (Submit button in Basic Info tab)
5. **delete_lesson** - Deletes a lesson (Submit button in Delete Lesson Modal)

### Modal Forms Requiring User Action

Each form requires the user to:
1. Click a button to open the modal (e.g., "Create Lesson", "New Module")
2. Fill in form fields
3. Click the "Submit" button to persist data

**Result:** No data is saved unless the user explicitly clicks a submit button.

## Preventing Auto-Save on Refresh

### What's Already Protected:

✅ **No beforeunload handlers** - No code executes when user navigates away or refreshes
✅ **No setInterval timers** - No periodic auto-save background processes
✅ **No setTimeout auto-saves** - No delayed auto-save on field changes
✅ **No AJAX auto-save** - No fetch/XMLHttpRequest calls triggered on changes
✅ **No change event handlers** - Form fields don't auto-submit on value changes

### Page Refresh Behavior:

When user refreshes the page:
1. Browser reloads the page from the server
2. `refreshCurriculum()` is NOT called on page load
3. Curriculum data is fetched fresh from database (only saved changes are displayed)
4. **Unsaved changes (in-memory only) are lost** - This is the expected behavior

## Security & Best Practices

### Current Implementation Follows Best Practices:

1. **Explicit user action required** - Standard for critical operations
2. **Form submission over AJAX** - Clear user intent, better browser history
3. **Post-Redirect-Get pattern** - Should be implemented to prevent duplicate submissions
4. **CSRF protection** - Ensure forms use CSRF tokens from `config/csrf.php`

### Recommendation: Add Unsaved Changes Warning

To provide better UX without auto-saving, consider adding:

```javascript
// Track form changes
let hasUnsavedChanges = false;

// Mark form as dirty when any input changes
document.getElementById('lessonForm').addEventListener('change', () => {
    hasUnsavedChanges = true;
});

// Warn user before leaving page with unsaved changes
window.addEventListener('beforeunload', (e) => {
    if (hasUnsavedChanges) {
        e.preventDefault();
        e.returnValue = 'You have unsaved changes. Are you sure you want to leave?';
    }
});

// Clear flag after successful submission
document.getElementById('lessonForm').addEventListener('submit', () => {
    hasUnsavedChanges = false;
});
```

This approach:
- **Does NOT auto-save** - Only warns user about potential data loss
- **Respects user intent** - Requires explicit form submission to save
- **Provides safety** - Prevents accidental loss of draft text

## Files Involved

- **c:\xampp\htdocs\lms\instructor\courses\course_builder.php** (1188 lines)
  - Contains all modal forms with explicit submit buttons
  - POST handlers for all CRUD operations
  - No auto-save mechanisms present

## Conclusion

The course_builder.php page is **properly designed** to prevent unwanted auto-saves. All data persistence requires:

1. ✅ Explicit user action (button click)
2. ✅ Form submission
3. ✅ POST request to server
4. ✅ Database update
5. ✅ Page refresh to see updated data

**No changes are required** unless you want to add optional unsaved changes warnings for better UX.
