设计模式9.1-外观模式

外观模式：定义了一个统一的接口，用来访问子系统中的一群接口。
外观模式和适配器模式在实现上比较相似，但是其应用的意图有所不同。
适配器模式意图改变一个接口成另一个接口，外观模式意图将一群接口简化

在示例中，我们有一个子系统House，其中有一群接口(door light air)。
当我们回家时，要开门，打开灯，打开空调。一个回家动作统一了多个接口。

---

<?php
interface DoorInterface
{
    public function open();

    public function close();
}

interface LightInterface
{
    public function on();

    public function off();
}

interface AirInterface
{
    public function start();

    public function stop();
}

class Door implements DoorInterface
{
    public function open()
    {
        echo "open the door<br>\n";
    }

    public function close()
    {
        echo "close the door<br>\n";
    }
}

class Light implements LightInterface
{
    public function on()
    {
        echo "turn on the light<br>\n";
    }

    public function off()
    {
        echo "turn off the light<br>\n";
    }
}

class Air implements AirInterface
{
    public function start()
    {
        echo "start the air<br>\n";
    }

    public function stop()
    {
        echo "stop the air<br>\n";
    }
}



class House
{
    private $door;
    private $light;
    private $air;

    public function __construct(DoorInterface $door, LightInterface $light, AirInterface $air)
    {
        $this->door = $door;
        $this->light = $light;
        $this->air = $air;
    }

    public function goBackHome()
    {
        $this->door->open();
        $this->light->on();
        $this->air->start();
    }

    public function leaveHome()
    {
        $this->door->close();
        $this->light->off();
        $this->air->stop();
    }
}


class Test
{
    public function run()
    {
        $door = new Door();
        $light = new Light();
        $air = new Air();


        $house = new House($door, $light, $air);

        $house->goBackHome();
        echo "<hr>";
        $house->leaveHome();
    }
}

$test = new Test();

$test->run();