{
  "compilerOptions": {
    "strict": true,
    "noUncheckedIndexedAccess": true,
    "noImplicitReturns": true
  }
}

// ✅ Good: interface for object shapes
interface User {
  id: string
  name: string
  email: string
  createdAt: Date
}

// ✅ Good: type for unions and intersections
type Status = 'active' | 'inactive' | 'suspended'
type ApiResponse<T> = { data: T; error: null } | { data: null; error: string }

// ❌ Bad
function parseJSON(json: string): any {
  return JSON.parse(json)
}

// ✅ Good
function parseJSON(json: string): unknown {
  return JSON.parse(json)
}

// With type guard
function isUser(data: unknown): data is User {
  return typeof data === 'object' && data !== null && 'id' in data && 'name' in data
}

type Shape =
  | { kind: 'circle'; radius: number }
  | { kind: 'rectangle'; width: number; height: number }
  | { kind: 'triangle'; base: number; height: number }

function area(shape: Shape): number {
  switch (shape.kind) {
    case 'circle':
      return Math.PI * shape.radius ** 2
    case 'rectangle':
      return shape.width * shape.height
    case 'triangle':
      return (shape.base * shape.height) / 2
  }
}

function getProperty<T, K extends keyof T>(obj: T, key: K): T[K] {
  return obj[key]
}

// Type-safe object access
const user: User = { id: '1', name: 'Ahmed', email: '[email protected]', createdAt: new Date() }
const name = getProperty(user, 'name') // string

// Partial makes all properties optional
type UpdateUser = Partial<User>

// Pick selects specific properties
type UserPreview = Pick<User, 'id' | 'name'>

// Omit excludes specific properties
type CreateUser = Omit<User, 'id' | 'createdAt'>

// Record creates an object type
type UserRoles = Record<string, 'admin' | 'user' | 'viewer'>