# Frontend Architecture

## Overview

This application has **4 distinct frontends**, each with its own templates and static assets:

1. **Platform** - Public platform pages (homepage, about, contact)
2. **Admin** - Administrative control panel
3. **Store** - Store management portal
4. **Storefront** - Customer-facing e-commerce store

## Directory Structure

```
app/
├── templates/
│   ├── platform/          # Platform public pages
│   ├── admin/             # Admin portal pages
│   ├── store/            # Store portal pages
│   ├── storefront/        # Storefront customer pages
│   └── shared/            # Shared components (emails, errors)
│
└── static/
    ├── platform/          # Platform static assets
    │   ├── js/
    │   ├── css/
    │   └── img/
    ├── admin/             # Admin static assets
    │   ├── js/
    │   ├── css/
    │   └── img/
    ├── store/            # Store static assets
    │   ├── js/
    │   ├── css/
    │   └── img/
    ├── storefront/        # Storefront static assets
    │   ├── js/
    │   ├── css/
    │   └── img/
    └── shared/            # Shared assets (icons, utilities)
        ├── js/
        ├── css/
        └── img/
```

## Frontend Details

### 1. Platform Frontend

**Purpose:** Public-facing platform pages (marketing, info pages)

**Location:**
- Templates: `app/templates/public/`
- Static: `static/public/`

**Pages:**
- Homepage (multiple layouts: default, minimal, modern)
- Content pages (about, privacy, terms)
- Landing pages

**Features:**
- SEO-optimized
- Multi-layout homepage support
- Content management system integration
- Responsive design

**Routes:** `/`, `/about`, `/contact`, etc.

**Authentication:** Not required (public access)

---

### 2. Admin Frontend

**Purpose:** Platform administration and management

**Location:**
- Templates: `app/templates/admin/`
- Static: `static/admin/`

**Pages:**
- Dashboard
- Store management
- User management
- Content management
- Theme customization
- System settings
- Logs and monitoring
- Code quality dashboard

**Technology Stack:**
- Alpine.js for reactive components
- Tailwind CSS for styling
- Heroicons for icons
- Centralized logging system
- API-driven architecture

**Routes:** `/admin/*`

**Authentication:** Admin role required

---

### 3. Store Frontend

**Purpose:** Store portal for product and order management

**Location:**
- Templates: `app/templates/store/`
- Static: `static/store/`

**Pages:**
- Store dashboard
- Product management
- Inventory management
- Order management
- Analytics
- Profile settings

**Technology Stack:**
- Alpine.js for reactive components
- Tailwind CSS for styling
- Heroicons for icons
- API-driven architecture
- Store context middleware

**Routes:** `/store/{store_code}/*`

**Authentication:** Store role required

---

### 4. Storefront Frontend

**Purpose:** Customer-facing e-commerce store

**Location:**
- Templates: `app/templates/storefront/`
- Static: `static/storefront/`

**Pages:**
- Product catalog
- Product details
- Shopping cart
- Checkout
- Order tracking
- Customer account

**Technology Stack:**
- Alpine.js for interactive features
- Tailwind CSS for styling
- E-commerce specific components
- Payment integration
- Shopping cart management

**Routes:** `/storefront/*`

**Authentication:** Optional (required for checkout)

---

## Using Static Assets

Each frontend has its own static directory for frontend-specific assets. Use the appropriate directory based on which frontend the asset belongs to.

### Platform Static Assets (`static/public/`)

**JavaScript Files:**
```html
<!-- In platform templates -->
<script src="{{ url_for('static', path='platform/js/homepage.js') }}"></script>
<script src="{{ url_for('static', path='platform/js/animations.js') }}"></script>
```

**CSS Files:**
```html
<link href="{{ url_for('static', path='platform/css/styles.css') }}" rel="stylesheet">
<link href="{{ url_for('static', path='platform/css/landing.css') }}" rel="stylesheet">
```

**Images:**
```html
<img src="{{ url_for('static', path='platform/img/hero-banner.jpg') }}" alt="Hero">
<img src="{{ url_for('static', path='platform/img/features/feature-1.svg') }}" alt="Feature">
```

**Current Usage:** Platform currently uses only shared assets (fonts, Tailwind CSS). Platform-specific directories are ready for future platform-specific assets.

---

### Admin Static Assets (`static/admin/`)

**JavaScript Files:**
```html
<!-- In admin templates -->
<script src="{{ url_for('static', path='admin/js/dashboard.js') }}"></script>
<script src="{{ url_for('static', path='admin/js/stores.js') }}"></script>
```

**CSS Files:**
```html
<link href="{{ url_for('static', path='admin/css/custom.css') }}" rel="stylesheet">
```

**Images:**
```html
<img src="{{ url_for('static', path='admin/img/placeholder.png') }}" alt="Placeholder">
```

---

### Store Static Assets (`static/store/`)

**JavaScript Files:**
```html
<!-- In store templates -->
<script src="{{ url_for('static', path='store/js/dashboard.js') }}"></script>
<script src="{{ url_for('static', path='store/js/products.js') }}"></script>
```

**CSS Files:**
```html
<link href="{{ url_for('static', path='store/css/custom.css') }}" rel="stylesheet">
```

**Images:**
```html
<img src="{{ url_for('static', path='store/img/no-products.svg') }}" alt="No Products">
```

---

### Storefront Static Assets (`static/storefront/`)

**JavaScript Files:**
```html
<!-- In storefront templates -->
<script src="{{ url_for('static', path='storefront/js/cart.js') }}"></script>
<script src="{{ url_for('static', path='storefront/js/checkout.js') }}"></script>
```

**CSS Files:**
```html
<link href="{{ url_for('static', path='storefront/css/product-gallery.css') }}" rel="stylesheet">
```

**Images:**
```html
<img src="{{ url_for('static', path='storefront/img/placeholder-product.jpg') }}" alt="Product">
```

---

### When to Use Shared vs. Frontend-Specific

**Use `static/shared/` when:**
- Asset is used by 2 or more frontends
- Common utilities (icons, API client, utilities)
- Brand assets (logos, favicons)
- Core libraries (Alpine.js, Tailwind CSS fallbacks)

**Use `static/{frontend}/` when:**
- Asset is only used by one specific frontend
- Frontend-specific styling
- Frontend-specific JavaScript components
- Frontend-specific images/graphics

**Example Decision Tree:**
```
Icon system (used by all 4 frontends) → static/shared/js/icons.js
Admin dashboard chart → static/admin/js/charts.js
Store product form → static/store/js/product-form.js
Platform hero image → static/public/img/hero.jpg
Storefront product carousel → static/storefront/js/carousel.js
```

---

## Module Static Files

Since January 2026, **module-specific JavaScript** is organized within each module's directory. This keeps modules self-contained and follows the plug-and-play architecture.

### Directory Structure

```
app/modules/{module}/static/
├── admin/js/           # Admin pages for this module
├── store/js/          # Store pages for this module
├── shared/js/          # Shared across admin/store for this module
└── storefront/js/      # Storefront pages for this module (if applicable)
```

### How Module Static Files Are Served

Module static files are mounted at `/static/modules/{module_name}/`:

```python
# In main.py (automatic for all modules with static/ directory)
app.mount("/static/modules/orders", StaticFiles(directory="app/modules/orders/static"))
```

### Referencing Module Static Files

**In templates, use the `{module}_static` URL name:**

```html
<!-- Orders module JS -->
<script src="{{ url_for('orders_static', path='admin/js/orders.js') }}"></script>
<script src="{{ url_for('orders_static', path='store/js/order-detail.js') }}"></script>

<!-- Billing module JS (includes shared feature-store) -->
<script src="{{ url_for('billing_static', path='shared/js/feature-store.js') }}"></script>
<script src="{{ url_for('billing_static', path='store/js/billing.js') }}"></script>

<!-- Marketplace module JS -->
<script src="{{ url_for('marketplace_static', path='store/js/onboarding.js') }}"></script>
```

### Module vs. Platform Static Files

| Location | Purpose | Example Files |
|----------|---------|---------------|
| `static/admin/js/` | Platform-level admin (not module-specific) | dashboard.js, login.js, platforms.js, stores.js, admin-users.js |
| `static/store/js/` | Store core (not module-specific) | dashboard.js, login.js, profile.js, settings.js, team.js |
| `static/shared/js/` | Shared utilities across all frontends | api-client.js, utils.js, money.js, icons.js |
| `app/modules/*/static/` | Module-specific functionality | orders.js, products.js, billing.js, etc. |

### Current Module JS Organization

| Module | Admin JS | Store JS | Shared JS |
|--------|----------|-----------|-----------|
| **orders** | orders.js | orders.js, order-detail.js | - |
| **catalog** | products.js, product-*.js | products.js, product-create.js | - |
| **inventory** | inventory.js | inventory.js | - |
| **customers** | customers.js | customers.js | - |
| **billing** | billing-history.js, subscriptions.js, subscription-tiers.js | billing.js, invoices.js | feature-store.js, upgrade-prompts.js |
| **messaging** | messages.js, notifications.js, email-templates.js | messages.js, notifications.js, email-templates.js | - |
| **marketplace** | marketplace*.js, letzshop*.js | letzshop.js, marketplace.js, onboarding.js | - |
| **monitoring** | monitoring.js, background-tasks.js, imports.js, logs.js | - | - |
| **dev_tools** | testing-*.js, code-quality-*.js, icons-page.js, components.js | - | - |
| **cms** | content-pages.js, content-page-edit.js | content-pages.js, content-page-edit.js, media.js | media-picker.js |
| **analytics** | - | analytics.js | - |
| **tenancy** | merchants*.js, stores*.js, platforms*.js, admin-users*.js, users*.js | login.js, team.js, profile.js, settings.js | - |
| **core** | dashboard.js, settings.js, my-menu-config.js, login.js, init-alpine.js | dashboard.js, init-alpine.js | store-selector.js |

### Platform Static Files (Not in Modules)

Only framework-level files remain in `static/`:

**Admin Framework (`static/admin/js/`):**
- `module-config.js` - Module system configuration UI
- `module-info.js` - Module information display

**Shared Utilities (`static/shared/js/`):**
- `api-client.js` - Core HTTP client with auth
- `utils.js` - Date formatting, currency, toasts
- `money.js` - Money/currency handling
- `icons.js` - Heroicons SVG definitions
- `log-config.js` - Centralized logging
- `lib/` - Third-party libraries (Alpine.js, Chart.js, etc.)

### User Type Distinction

The codebase distinguishes between three types of users:

| Type | Management JS | Location | Description |
|------|---------------|----------|-------------|
| **Admin Users** | admin-users.js | `app/modules/tenancy/static/admin/js/` | Platform administrators (super admins, platform admins) |
| **Platform Users** | users.js | `app/modules/tenancy/static/admin/js/` | Store/merchant users who log into the platform |
| **Shop Customers** | customers.js | `app/modules/customers/static/` | End customers who buy from stores |

All user management JS is now in self-contained modules:
- `admin-users.js` and `users.js` are in the **tenancy** module (manages platform users)
- `customers.js` is in the **customers** module (manages storefront customers)

---

## Shared Resources

### Templates (`app/templates/shared/`)

**Shared components used across multiple frontends:**
- Email templates
- Error pages (404, 500)
- Common partials

### Static Assets (`static/shared/`)

**Shared JavaScript:**
- `js/icons.js` - Heroicons system (used by all frontends)
- `js/utils.js` - Common utilities
- `js/api-client.js` - API communication
- `js/log-config.js` - Centralized logging

**Shared CSS:**
- Common utility classes
- Shared theme variables

**Shared Images:**
- Logos
- Brand assets
- Icons

---

## Architecture Principles

### 1. Separation of Concerns

Each frontend is completely isolated:
- Own templates directory
- Own static assets directory
- Own JavaScript components
- Own CSS styles

**Benefits:**
- Clear boundaries
- Independent development
- No cross-contamination
- Easy to maintain

### 2. Shared Core

Common functionality is shared via `static/shared/`:
- Icon system
- API client
- Utilities
- Logging

**Benefits:**
- DRY principle
- Consistent behavior
- Single source of truth
- Easy updates

### 3. Template Inheritance

Each frontend has a base template:
- `platform/base.html`
- `admin/base.html`
- `store/base.html`
- `storefront/base.html`

**Benefits:**
- Consistent layout within frontend
- Easy to customize per frontend
- Different design systems possible

### 4. API-Driven

All frontends communicate with backend via APIs:
- `/api/v1/admin/*` - Admin APIs
- `/api/v1/store/*` - Store APIs
- `/api/v1/storefront/*` - Storefront APIs
- `/api/v1/platform/*` - Platform APIs

**Benefits:**
- Clear backend contracts
- Testable independently
- Can be replaced with SPA if needed
- Mobile app ready

---

## Frontend Technology Matrix

| Frontend | Framework | CSS       | Icons      | Auth Required | Base URL          |
|----------|-----------|-----------|------------|---------------|-------------------|
| Platform | Alpine.js | Tailwind  | Heroicons  | No            | `/`               |
| Admin    | Alpine.js | Tailwind  | Heroicons  | Yes (Admin)   | `/admin`          |
| Store   | Alpine.js | Tailwind  | Heroicons  | Yes (Store)  | `/store/{code}`  |
| Storefront | Alpine.js | Tailwind  | Heroicons  | Optional      | `/storefront`     |

---

## Development Guidelines

### Adding a New Page

1. **Determine which frontend** the page belongs to
2. **Create template** in appropriate `app/templates/{frontend}/` directory
3. **Create JavaScript** (if needed) in `static/{frontend}/js/`
4. **Create CSS** (if needed) in `static/{frontend}/css/`
5. **Add route** in appropriate route handler
6. **Update navigation** in frontend's base template

### Using Shared Resources

**Icons:**
```html
<span x-html="$icon('icon-name', 'w-5 h-5')"></span>
```

**API Client:**
```javascript
const data = await apiClient.get('/api/v1/admin/users');
```

**Utilities:**
```javascript
Utils.showToast('Success!', 'success');
Utils.formatDate(dateString);
```

**Logging:**
```javascript
const log = window.LogConfig.loggers.myPage;
log.info('Page loaded');
```

### Frontend-Specific Resources

**Platform-specific JavaScript:**
```html
<script src="{{ url_for('static', path='platform/js/homepage.js') }}"></script>
```

**Admin-specific CSS:**
```html
<link href="{{ url_for('static', path='admin/css/dashboard.css') }}" rel="stylesheet">
```

**Store-specific images:**
```html
<img src="{{ url_for('static', path='store/img/logo.png') }}">
```

---

## Migration Notes

### Moving Assets Between Frontends

If an asset is used by multiple frontends:
1. **Move to `static/shared/`**
2. **Update all references**
3. **Test all affected frontends**

If an asset is only used by one frontend:
1. **Move to `static/{frontend}/`**
2. **Update references in that frontend only**

### Deprecation Path

When removing a frontend:
1. Remove `app/templates/{frontend}/`
2. Remove `static/{frontend}/`
3. Remove routes
4. Update documentation

---

## Future Considerations

### Potential Additional Frontends

- **Partner Portal** - For business partners/affiliates
- **API Documentation** - Interactive API docs (Swagger UI)
- **Mobile App** - Native mobile using existing APIs

### Frontend Modernization

Each frontend can be independently modernized:
- Replace Alpine.js with React/Vue/Svelte
- Add TypeScript
- Implement SSR/SSG
- Convert to PWA

The API-driven architecture allows this flexibility.

---

## Testing Strategy

### Per-Frontend Testing

Each frontend should have:
- **Unit tests** for JavaScript components
- **Integration tests** for API interactions
- **E2E tests** for critical user flows
- **Accessibility tests**
- **Responsive design tests**

### Shared Resource Testing

Shared resources need:
- **Unit tests** for utilities
- **Integration tests** with all frontends
- **Visual regression tests** for icons

---

## Performance Optimization

### Per-Frontend Optimization

Each frontend can optimize independently:
- Code splitting
- Lazy loading
- Asset minification
- CDN deployment
- Browser caching

### Shared Resource Optimization

Shared resources are cached globally:
- Long cache headers
- Versioning via query params
- CDN distribution
- Compression

---

## Security Considerations

### Frontend-Specific Security

Each frontend has different security needs:
- **Platform:** XSS protection, CSP
- **Admin:** CSRF tokens, admin-only routes
- **Store:** Store isolation, rate limiting
- **Shop:** PCI compliance, secure checkout

### Shared Security

All frontends use:
- JWT authentication
- HTTPS only
- Secure headers
- Input sanitization

---

## Conclusion

The 4-frontend architecture provides:
- ✅ Clear separation of concerns
- ✅ Independent development and deployment
- ✅ Shared core functionality
- ✅ Flexibility for future changes
- ✅ Optimized for each user type
- ✅ Maintainable and scalable

Each frontend serves a specific purpose and audience, with shared infrastructure for common needs.