Structs

package main

import (
    "fmt"
    "time"
)

// 1. Definisi struct dasar
type Person struct {
    FirstName string
    LastName  string
    Age       int
}

// 2. Struct dengan embedded struct
type Address struct {
    Street  string
    City    string
    Country string
}

type Employee struct {
    Person    // Embedded struct
    Address   // Embedded struct
    JobTitle  string
    HireDate  time.Time
}

// 3. Method untuk struct
func (p Person) FullName() string {
    return fmt.Sprintf("%s %s", p.FirstName, p.LastName)
}

func (p *Person) Birthday() {
    p.Age++
}

// 4. Constructor-like function
func NewEmployee(firstName, lastName string, age int, 
    jobTitle string) *Employee {
    return &Employee{
        Person: Person{
            FirstName: firstName,
            LastName:  lastName,
            Age:       age,
        },
        JobTitle: jobTitle,
        HireDate: time.Now(),
    }
}

func main() {
    // Contoh 1: Membuat dan menggunakan struct
    person := Person{
        FirstName: "John",
        LastName:  "Doe",
        Age:       30,
    }
    
    fmt.Printf("Person: %+v\n", person)
    fmt.Printf("Full Name: %s\n", person.FullName())

    // Contoh 2: Pointer ke struct
    person.Birthday()
    fmt.Printf("\nSetelah ulang tahun: %+v\n", person)

    // Contoh 3: Struct literal dengan field names
    addr := Address{
        Street:  "Jalan Merdeka 123",
        City:    "Jakarta",
        Country: "Indonesia",
    }

    // Contoh 4: Struct dengan embedded struct
    emp := Employee{
        Person: Person{
            FirstName: "Jane",
            LastName:  "Smith",
            Age:       25,
        },
        Address:  addr,
        JobTitle: "Software Engineer",
        HireDate: time.Now(),
    }

    fmt.Printf("\nEmployee: %+v\n", emp)
    fmt.Printf("Employee Name: %s\n", emp.FullName())
    fmt.Printf("Employee City: %s\n", emp.City) // Promoted field

    // Contoh 5: Menggunakan constructor
    newEmp := NewEmployee("Bob", "Johnson", 35, "Manager")
    fmt.Printf("\nNew Employee: %+v\n", newEmp)

    // Contoh 6: Anonymous struct
    point := struct {
        X, Y int
    }{
        X: 10,
        Y: 20,
    }
    
    fmt.Printf("\nPoint: %+v\n", point)

    // Contoh 7: Slice of structs
    people := []Person{
        {FirstName: "Alice", LastName: "Brown", Age: 28},
        {FirstName: "Charlie", LastName: "Davis", Age: 32},
    }

    fmt.Printf("\nPeople:\n")
    for _, p := range people {
        fmt.Printf("- %s (%d years)\n", p.FullName(), p.Age)
    }
}