Single Responsibility Principle `idealImpl`

idealImplCustomer.go

package main

import (
	"encoding/json"
	"fmt"
)

type CustomerInfo interface {
	Name() string
	Address() string
}

type Customer struct {
	name    string
	address string
}

func (c Customer) Name() string {
	return c.name
}

func (c Customer) Address() string {
	return c.address
}

type CompleteOrder interface {
	Complete()
}

type Order struct {
	Id       int
	Customer CustomerInfo
	complete bool
}

func (o Order) Bill() int {
	fmt.Println("Billed", o.Customer.Name())
	return o.Id * 2
}

func (o *Order) Complete() {
	o.complete = true
}

type Delivery struct {
	Order *Order
}

func (d *Delivery) Deliver() {
	fmt.Printf("Order: %d delivered!\n", d.Order.Id)
	d.Order.Complete()
}

func main() {
	c := Customer{
		name:    "Bob",
		address: "California",
	}
	o := Order{
		Id:       1,
		Customer: c,
	}
	o.Bill()
	d := Delivery{
		Order: &o,
	}
	d.Deliver()
	bytes, _ := json.Marshal(d)
	fmt.Println(string(bytes))
}