# Copilot Instructions

## Code Style
- Use TypeScript with strict mode
- Prefer functional components with hooks
- Use Tailwind CSS for styling

## Project Context
This is a Next.js 14 app using the App Router.
API routes are in `app/api/`.

# Project Context

## Tech Stack
- Next.js 14 with App Router
- TypeScript 5.3+
- Tailwind CSS 3.4
- Prisma ORM with PostgreSQL

## Architecture
- `app/` - Next.js App Router pages and API routes
- `components/` - React components
- `lib/` - Utility functions and shared code
- `prisma/` - Database schema and migrations

# Code Standards

## TypeScript
- Enable strict mode
- Prefer `interface` over `type` for object shapes
- Use explicit return types on functions

## React
- Use functional components exclusively
- Prefer named exports
- Extract hooks to `hooks/` directory

## Error Handling
- Use Result pattern for fallible operations
- Always handle async errors with try/catch
- Log errors with structured format

# Naming Conventions

## Files
- Components: PascalCase (Button.tsx)
- Utilities: camelCase (formatDate.ts)
- Constants: SCREAMING_SNAKE_CASE

## Code
- Boolean variables: is*, has*, should* prefix
- Event handlers: handle* prefix (handleClick)
- Async functions: *Async suffix

# Testing Guidelines

## Unit Tests
- Use Vitest for unit testing
- Place tests next to source files (*.test.ts)
- Mock external dependencies

## Test Patterns
```typescript
describe('Component', () => {
  it('should render correctly', () => {
    // Arrange, Act, Assert pattern
  });
});

### API Patterns
```markdown
# API Patterns

## Route Handlers
```typescript
// Standard response format
return NextResponse.json({
  data: result,
  error: null,
  meta: { timestamp: Date.now() }
});

// Error response
return NextResponse.json(
  { data: null, error: { code: 'NOT_FOUND', message: '...' } },
  { status: 404 }
);

### Do's and Don'ts
```markdown
# Guidelines

## Do
- Write self-documenting code
- Add JSDoc comments for public APIs
- Use meaningful variable names

## Don't
- Use `any` type
- Leave console.log in production code
- Commit sensitive data