<!-- markdownlint-disable MD013 -->

# Architecture Documentation

## Overview

kilo-cv is a full-stack web application for managing and displaying a professional CV/resume. It features a public-facing CV display page and an authenticated admin panel for content management.

### Key Features

- **Public CV Display**: Responsive, animated CV page with sections for experience, skills, education, and projects
- **Admin Panel**: Authenticated interface for editing CV content
- **REST API**: Backend API for data management
- **Export/Import**: JSON export and import functionality
- **API Documentation**: Interactive Swagger UI

## Technology Stack

### Frontend

| Technology | Version | Purpose |
|------------|---------|---------|
| React | 19.x | UI library |
| Vite | 7.x | Build tool and dev server |
| Tailwind CSS | 4.x | Styling |
| Framer Motion | 12.x | Animations |
| Lucide React | 0.574.x | Icon library |
| React Router DOM | 7.x | Client-side routing |

### Backend

| Technology | Version | Purpose |
|------------|---------|---------|
| Express.js | 4.x | REST API server |
| Knex.js | 3.x | SQL query builder |
| better-sqlite3 | 11.x | SQLite database driver |
| swagger-jsdoc | 6.x | OpenAPI documentation generation |
| swagger-ui-express | 5.x | Swagger UI serving |

## Directory Structure

```
kilo-cv/
├── src/                          # Frontend source
│   ├── components/               # Public CV display components
│   │   ├── Hero.jsx             # Name, title, introduction
│   │   ├── Experience.jsx       # Work history section
│   │   ├── Skills.jsx           # Skills by category
│   │   ├── Education.jsx        # Education history
│   │   ├── Projects.jsx         # Project showcase
│   │   └── Contact.jsx          # Contact information
│   ├── admin/                    # Admin panel
│   │   ├── AdminLayout.jsx      # Admin layout with navigation
│   │   ├── AdminPersonal.jsx    # Personal info editor
│   │   ├── AdminExperience.jsx  # Experience editor
│   │   ├── AdminSkills.jsx      # Skills editor
│   │   ├── AdminEducation.jsx   # Education editor
│   │   ├── AdminProjects.jsx    # Projects editor
│   │   ├── pages/
│   │   │   └── LoginPage.jsx    # Authentication page
│   │   ├── sections/            # Reusable form components
│   │   │   ├── PersonalForm.jsx
│   │   │   ├── ExperienceForm.jsx
│   │   │   ├── SkillsForm.jsx
│   │   │   ├── EducationForm.jsx
│   │   │   └── ProjectsForm.jsx
│   │   ├── hooks/               # React contexts and custom hooks
│   │   │   ├── CVContext.jsx    # CV data state management
│   │   │   ├── AuthContext.jsx  # Authentication state
│   │   │   ├── useCVData.js     # CV data access hook
│   │   │   └── useFormValidation.js
│   │   └── components/
│   │       └── ExportButton.jsx
│   ├── lib/                      # Utilities and API client
│   │   ├── api.js               # API client functions
│   │   ├── auth.js              # Token management
│   │   ├── cv-data.js           # CV validation utilities
│   │   └── cv.json              # Default CV data structure
│   ├── data/
│   │   └── cv.js
│   ├── App.jsx                   # Root component with routing
│   ├── main.jsx                  # React entry point
│   └── index.css                 # Global styles (Tailwind)
├── backend/                      # Backend source
│   ├── routes/                   # API route handlers
│   │   ├── cv.js                # CV CRUD endpoints
│   │   ├── auth.js              # Authentication endpoints
│   │   └── docs.js              # Swagger documentation route
│   ├── db/
│   │   └── init.js              # Database initialization
│   ├── migrations/
│   │   └── 20260220000001_initial_schema.js
│   ├── middleware/
│   │   └── auth.js              # JWT authentication middleware
│   ├── seeds/
│   │   └── initial_cv_data.js   # Initial data seeding
│   ├── __tests__/
│   │   └── api.test.js          # API tests
│   ├── server.js                 # Express server entry point
│   └── knexfile.js               # Knex configuration
├── tests/                        # Test suites
│   ├── e2e/                      # Playwright E2E tests
│   ├── integration/              # Integration tests
│   ├── regression/               # Snapshot/regression tests
│   └── performance/              # k6 and Lighthouse tests
├── docs/                         # Documentation
├── public/                       # Static assets
└── .github/                      # CI/CD workflows
```

## Frontend Architecture

### Routing Structure

```
/                    → Public CV display
/admin               → Admin panel (requires auth)
/admin/login         → Login page
/admin/personal      → Personal info editor
/admin/experience    → Experience editor
/admin/skills        → Skills editor
/admin/education     → Education editor
/admin/projects      → Projects editor
```

### Component Hierarchy

```
App
├── CVProvider (context)
│   └── AuthProvider (context)
│       ├── Routes
│       │   ├── "/" → CV Display Page
│       │   │   └── Hero, Experience, Skills, Education, Projects, Contact
│       │   └── "/admin/*" → AdminLayout
│       │       ├── LoginPage (unauthenticated)
│       │       └── Admin* Pages (authenticated)
│       │           └── *Form components
```

### State Management

The application uses React Context for state management:

**CVContext** (`src/admin/hooks/CVContext.jsx`)
- Manages CV data state
- Provides `useCVData()` hook for components
- Handles API communication for CRUD operations

**AuthContext** (`src/admin/hooks/AuthContext.jsx`)
- Manages authentication state
- Handles token storage and validation
- Provides `useAuth()` hook for protected routes

### Custom Hooks

| Hook | Purpose |
|------|---------|
| `useCVData()` | Access CV data and CRUD operations |
| `useAuth()` | Access authentication state and methods |
| `useFormValidation()` | Form validation with error handling |

### Styling

- **Tailwind CSS 4** with `@tailwindcss/vite` plugin
- Utility-first approach throughout
- Responsive design with mobile-first breakpoints
- Animations via Framer Motion

## Backend Architecture

### API Endpoints

| Endpoint | Method | Description | Auth |
|----------|--------|-------------|------|
| `/api/auth/config` | GET | Get auth configuration | No |
| `/api/auth/login` | POST | Authenticate with password | No |
| `/api/cv` | GET | Get CV data | No |
| `/api/cv` | PUT | Update CV data | Yes |
| `/api/cv/export` | GET | Export CV as JSON | No |
| `/api/cv/import` | POST | Import CV from JSON | Yes |
| `/api/docs` | GET | Swagger UI documentation | No |
| `/health` | GET | Health check endpoint | No |

### Request/Response Examples

**Get CV Data**
```http
GET /api/cv
Response: {
  "personal": { "name": "...", "title": "...", ... },
  "experience": [...],
  "skills": {...},
  "education": [...],
  "projects": [...]
}
```

**Update CV Data**
```http
PUT /api/cv
Authorization: Bearer <token>
Body: { "personal": {...}, "experience": [...], ... }
Response: { "success": true }
```

**Login**
```http
POST /api/auth/login
Body: { "password": "..." }
Response: { "token": "..." }
```

### Database Schema

Single-table design for simplicity:

```sql
CREATE TABLE cv_data (
  id          INTEGER PRIMARY KEY CHECK (id = 1),
  data        TEXT NOT NULL,
  updated_at  DATETIME DEFAULT CURRENT_TIMESTAMP
);
```

The CV data is stored as a JSON document in the `data` column:

```json
{
  "personal": {
    "name": "string",
    "title": "string",
    "intro": "string",
    "email": "string",
    "github": "string",
    "linkedin": "string",
    "location": "string"
  },
  "experience": [
    {
      "company": "string",
      "position": "string",
      "startDate": "YYYY-MM",
      "endDate": "YYYY-MM or null",
      "description": "string",
      "highlights": ["string", ...]
    }
  ],
  "skills": {
    "Category Name": ["skill1", "skill2", ...]
  },
  "education": [
    {
      "institution": "string",
      "degree": "string",
      "field": "string",
      "startDate": "YYYY",
      "endDate": "YYYY"
    }
  ],
  "projects": [
    {
      "name": "string",
      "description": "string",
      "technologies": ["tech1", ...],
      "url": "string"
    }
  ]
}
```

### Authentication

Two authentication modes are supported:

**Simple Mode** (default)
- Random password generated on server startup
- Password logged to console
- JWT token-based authentication
- Suitable for personal/single-user deployments

**Keycloak Mode** (optional)
- SSO integration via Keycloak
- Configure via environment variables
- Suitable for enterprise deployments

Environment variables for Keycloak:
```bash
AUTH_MODE=keycloak
KEYCLOAK_URL=https://keycloak.example.com
KEYCLOAK_REALM=your-realm
KEYCLOAK_CLIENT_ID=cv-app
```

### Middleware

**Auth Middleware** (`backend/middleware/auth.js`)
- Validates JWT token from Authorization header
- Attaches user info to request
- Returns 401 for invalid/missing tokens

## Design Patterns

### Frontend Patterns

1. **Context Provider Pattern**
   - `CVProvider` and `AuthProvider` wrap the application
   - Provides global state without prop drilling

2. **Custom Hook Pattern**
   - `useCVData()`, `useAuth()` expose context values
   - Encapsulates complex logic

3. **Container/Presentational Pattern**
   - Admin pages fetch data from context (container)
   - Form components handle UI (presentational)

4. **Form Validation Pattern**
   - `useFormValidation` hook provides reusable validation
   - Error state management standardized

### Backend Patterns

1. **Route Handler Pattern**
   - Modular Express routers in `/routes`
   - Clean separation of concerns

2. **Middleware Pattern**
   - Auth middleware for protected routes
   - Composable request processing

3. **Repository Pattern**
   - `getDB()` returns Knex instance
   - Database access abstracted from route handlers

4. **Migration-based Schema**
   - Knex migrations for version control
   - Rollback capability

## Testing Architecture

| Layer | Tool | Location | Purpose |
|-------|------|----------|---------|
| Unit | Vitest | `src/lib/__tests__/`, `src/admin/hooks/__tests__/` | Test utilities and hooks |
| API | Vitest + Supertest | `backend/__tests__/` | Test API endpoints |
| Integration | Vitest | `tests/integration/` | Test full-stack interactions |
| E2E | Playwright | `tests/e2e/` | Test user flows |
| Regression | Vitest | `tests/regression/` | Snapshot tests |
| Performance | k6, Lighthouse | `tests/performance/` | Load and performance testing |

### Test Commands

```bash
npm run test:run          # Run unit tests
npm run test:coverage     # Run tests with coverage
npm run test:integration  # Run integration tests
npm run test:e2e          # Run E2E tests (requires running server)
npm run test:regression   # Run regression tests
```

## Configuration

### Frontend Configuration

**Vite** (`vite.config.js`)
- React plugin with SWC
- Tailwind CSS plugin
- Proxy configuration for API

**Tailwind** (`src/index.css`)
- Tailwind imports
- Custom CSS variables

### Backend Configuration

**Environment Variables**

| Variable | Default | Description |
|----------|---------|-------------|
| `PORT` | 3001 | Server port |
| `AUTH_MODE` | simple | Authentication mode (simple/keycloak) |
| `KEYCLOAK_URL` | - | Keycloak server URL |
| `KEYCLOAK_REALM` | - | Keycloak realm |
| `KEYCLOAK_CLIENT_ID` | - | Keycloak client ID |

**Knex** (`backend/knexfile.js`)
- SQLite database configuration
- Migration and seed directories

## Development

### Prerequisites

- Node.js 20+
- npm 10+

### Getting Started

```bash
# Install frontend dependencies
npm install

# Install backend dependencies
cd backend && npm install

# Start backend server
npm run dev:backend

# In another terminal, start frontend
npm run dev
```

### Build

```bash
# Build frontend
npm run build

# Build outputs to dist/
```

### Docker

```bash
# Build and run with Docker Compose
docker-compose up --build
```

The Docker setup includes:
- Frontend container with nginx
- Backend container with Node.js
- SQLite volume for persistence

## Security Considerations

1. **Authentication**: JWT tokens with configurable expiration
2. **Secret Scanning**: Gitleaks pre-commit hook
3. **Input Validation**: Form validation on frontend, schema validation on backend
4. **CORS**: Configured for frontend origin
5. **SQL Injection**: Knex query builder prevents injection

## Future Considerations

- **Image Upload**: Profile picture support
- **PDF Export**: Generate PDF from CV data
- **Themes**: Customizable color schemes
- **Multi-language**: Internationalization support
- **Analytics**: View tracking for CV