Architecture Documentation

Complete architecture overview of the AI Store application.

System Overview

The AI Store is built as a modern Next.js application using the App Router architecture, providing server-side rendering, static generation, and client-side interactivity.

Technology Stack

Core

• Framework: Next.js 16 (App Router)
• Language: TypeScript
• Styling: Tailwind CSS
• Runtime: Node.js 18+

Key Libraries

• React 19.2.0
• Next.js 16.0.3
• TypeScript 5.x

Architecture Layers

1. Presentation Layer

Location: app/, components/

• Pages: Next.js App Router pages
• Components: Reusable React components
• Layouts: Shared layouts
• UI Components: Base UI components (Modal, Tooltip, etc.)

Responsibilities:

• User interface rendering
• User interactions
• Visual feedback
• Responsive design

2. Business Logic Layer

Location: hooks/, lib/

• Hooks: Custom React hooks for business logic
• Services: Business logic services
• State Management: State stores and persistence
• Validation: Form and input validation

Responsibilities:

• Business rules
• Data transformation
• State management
• Validation logic

3. Data Layer

Location: lib/data-fetching.ts, lib/api-cache.ts

• Data Fetching: API calls and data retrieval
• Caching: Response caching strategies
• State Persistence: LocalStorage/SessionStorage
• API Integration: External API integration

Responsibilities:

• Data fetching
• Caching
• Data persistence
• API communication

4. Infrastructure Layer

Location: lib/, app/api/

• API Routes: Next.js API routes
• Service Workers: PWA support
• Error Handling: Error boundaries and recovery
• Monitoring: Analytics and performance monitoring

Responsibilities:

• API endpoints
• Offline support
• Error handling
• Monitoring and logging

File Structure

├── app/                    # Next.js App Router
│   ├── layout.tsx         # Root layout
│   ├── page.tsx           # Home page
│   ├── api/               # API routes
│   │   ├── analytics/
│   │   ├── errors/
│   │   ├── events/
│   │   └── metrics/
│   └── [routes]/          # App routes
│
├── components/            # React components
│   ├── UI/                # Base UI components
│   │   ├── Accordion.tsx
│   │   └── Tabs.tsx
│   ├── Modal.tsx
│   ├── Tooltip.tsx
│   └── [other components]
│
├── hooks/                 # Custom React hooks
│   ├── useForm.ts
│   ├── useDataFetch.ts
│   └── [other hooks]
│
├── lib/                   # Utility libraries
│   ├── analytics.ts
│   ├── caching.ts
│   ├── search.ts
│   └── [other utilities]
│
├── types/                 # TypeScript types
│   └── app.ts
│
└── public/                # Static files
    ├── manifest.json
    └── sw.js

Data Flow

Client-Side Data Flow

User Action
    ↓
Component Event Handler
    ↓
Hook (useForm, useDataFetch, etc.)
    ↓
Service/Utility (lib/)
    ↓
API Call / State Update
    ↓
State Management
    ↓
Component Re-render

Server-Side Data Flow

Request
    ↓
Next.js Route Handler
    ↓
API Route (app/api/)
    ↓
Business Logic (lib/)
    ↓
Data Source / Cache
    ↓
Response

State Management

Local Component State

• React useState for component-specific state
• React useReducer for complex local state

Global State

• Custom state stores (lib/state-management.ts)
• Persisted state (lib/state-persistence.ts)
• React Context for theme, i18n, etc.

Server State

• Next.js Server Components for server state
• API routes for data mutations
• Caching with advancedCache

Caching Strategy

Client-Side Caching

• Browser Cache: Static assets
• Service Worker: Offline support
• Memory Cache: Runtime data (apiCache, advancedCache)

Server-Side Caching

• Next.js Cache: Static generation
• API Response Cache: API route responses
• CDN Cache: Static assets

Cache Strategies

1. Cache-First: Serve from cache, fallback to network
2. Network-First: Try network, fallback to cache
3. Stale-While-Revalidate: Serve stale, update in background
4. Network-Only: Always fetch fresh
5. Cache-Only: Only use cache

Error Handling

Error Boundaries

• ErrorBoundary: Basic error boundary
• ErrorBoundaryAdvanced: Advanced with recovery

Error Recovery

• Automatic recovery strategies
• Manual recovery UI
• Error logging and tracking

Error Types

1. Network Errors: Retry with exponential backoff
2. Validation Errors: User feedback
3. Application Errors: Error boundaries
4. System Errors: Logging and monitoring

Performance Optimization

Code Splitting

• Route-based splitting (Next.js automatic)
• Component lazy loading (next/dynamic)
• Dynamic imports

Image Optimization

• Next.js Image component
• WebP/AVIF format support
• Responsive images
• Lazy loading

Bundle Optimization

• Tree shaking
• Package import optimization
• CSS optimization
• Bundle analysis

Runtime Optimization

• Memoization (React.memo, useMemo)
• Virtual scrolling
• Debouncing/Throttling
• Intersection Observer

Security Architecture

Client-Side Security

• Input sanitization
• XSS prevention
• CSRF protection
• URL validation

Server-Side Security

• Security headers (CSP, XSS Protection)
• Rate limiting
• Input validation
• Authentication/Authorization

Data Security

• Encryption for sensitive data
• Secure storage
• HTTPS enforcement
• Secure cookies

PWA Architecture

Service Worker

• Offline support
• Cache strategies
• Background sync
• Push notifications (future)

Web App Manifest

• App metadata
• Icons and splash screens
• Display modes
• Theme colors

SEO Architecture

Server-Side Rendering

• Static generation for static pages
• Server-side rendering for dynamic pages
• Incremental Static Regeneration

Structured Data

• JSON-LD schemas
• Breadcrumbs
• Organization data
• Article/Product schemas

Meta Tags

• Dynamic meta tags
• Open Graph
• Twitter Cards
• Canonical URLs

Monitoring & Analytics

Performance Monitoring

• Web Vitals tracking
• Custom performance metrics
• Performance budgets
• Memory monitoring

Error Monitoring

• Error logging
• Error tracking
• Error recovery
• Error analytics

User Analytics

• Page views
• User events
• Conversions
• Engagement tracking

Internationalization

i18n Architecture

• Translation system
• Locale detection
• Persistent preferences
• Dynamic translations

Supported Locales

• English (en)
• German (de)
• French (fr)
• Spanish (es)
• Italian (it)

Testing Architecture

Testing Strategy

• Unit tests for utilities
• Component tests for UI
• Integration tests for flows
• E2E tests for critical paths

Testing Tools

• Jest
• React Testing Library
• Test utilities (lib/test-utils.tsx)

Deployment Architecture

Build Process

1. TypeScript compilation
2. Next.js build
3. Static optimization
4. Bundle generation

Deployment Targets

• Vercel (recommended)
• Netlify
• Any Node.js hosting
• Docker (future)

Scalability Considerations

Horizontal Scaling

• Stateless API routes
• CDN for static assets
• Database connection pooling

Vertical Scaling

• Code splitting
• Lazy loading
• Caching strategies
• Performance optimization

Future Enhancements

Planned Features

• Real-time updates (WebSockets)
• Advanced caching (Redis)
• Database integration
• Authentication system
• Payment integration
• Advanced analytics

Technical Debt

• Test coverage improvement
• Documentation updates
• Performance optimizations
• Security enhancements

Design Patterns

Used Patterns

• Component Composition: Reusable components
• Custom Hooks: Logic reuse
• Provider Pattern: Context providers
• Factory Pattern: Utility factories
• Observer Pattern: Event system
• Strategy Pattern: Caching strategies

Best Practices

Code Organization

• Feature-based structure
• Clear separation of concerns
• DRY principle
• Single responsibility

Performance

• Lazy loading
• Code splitting
• Image optimization
• Caching

Security

• Input validation
• XSS prevention
• CSRF protection
• Secure headers

Accessibility

• Semantic HTML
• ARIA attributes
• Keyboard navigation
• Screen reader support