package main

import "fmt"

/*
实例
汤宝宝成为了上市集团老总，他们集团有好多好多家分公司...
*/

type component interface {
	Show(prefix string)
	getName() string
}

type Department struct {
	name string
}

func (d *Department) Show(prefix string) {
	fmt.Print(prefix)
	fmt.Println(d.name)
}

func (d *Department) getName() string {
	return d.name
}

type Company struct {
	name     string
	children []component
}

func (c *Company) Show(prefix string) {
	fmt.Print(prefix)
	fmt.Println(c.name)
	for _, child := range c.children {
		child.Show(prefix + "-> ")
	}
}

func (c *Company) getName() string {
	return c.name
}

func (c *Company) Add(company component) {
	c.children = append(c.children, company)
	fmt.Printf("在%s下开设了%s\n", c.name, company.getName())
}

func (c *Company) Remove(company component) {
	for i, child := range c.children {
		if child == company {
			c.children = append(c.children[:i], c.children[i+1:]...)
			break
		}
	}
	fmt.Printf("在%s下裁撤了%s\n", c.name, company.getName())
}

func (c *Company) GetChild(i int) component {
	if i < 0 || i >= len(c.children) {
		return nil
	}
	return c.children[i]
}

func main() {
	fmt.Println("============= 组合模式 =============")

	headOffice := &Company{name: "汤氏总公司"}
	headOffice.Add(&Company{name: "汤氏A分公司"})
	headOffice.Add(&Department{name: "人事部"})
	headOffice.Add(&Department{name: "研发部"})
	headOffice.GetChild(0).(*Company).Add(&Department{name: "市场部"})
	headOffice.GetChild(0).(*Company).Add(&Department{name: "财务部"})
	headOffice.Remove(headOffice.GetChild(2))
	fmt.Println()
	headOffice.Show("~ ")
	fmt.Println()
	headOffice.GetChild(0).Show("~ ")
	fmt.Println()

	fmt.Println("=========== 组合模式结束 ===========")

}