CommandExample.php

<?php

interface CommandInterface
{
    public function execute();
}

class TurnOnCommand implements CommandInterface
{
    /**
     * @var Lamp
     */
    protected $lamp;

    /**
     * @param Lamp $lamp
     */
    public function __construct(Lamp $lamp)
    {
        $this->lamp = $lamp;
    }


    public function execute()
    {
        $this->lamp->turnOn();
    }
}

class TurnOffCommand implements CommandInterface
{
    /**
     * @var Lamp
     */
    protected $lamp;

    /**
     * @param Lamp $lamp
     */
    public function __construct(Lamp $lamp)
    {
        $this->lamp = $lamp;
    }


    public function execute()
    {
        $this->lamp->turnOff();
    }
}

class SosCommand implements CommandInterface
{
    /**
     * @var Lamp
     */
    protected $lamp;

    /**
     * @param Lamp $lamp
     */
    public function __construct(Lamp $lamp)
    {
        $this->lamp = $lamp;
    }

    private function signal($sleep)
    {
        $this->lamp->turnOn();
        sleep($sleep);
        $this->lamp->turnOff();
        sleep($sleep);
    }

    public function execute()
    {
        while (true) {
            for ($i = 0; $i < 3; $i++) {
                $this->signal(0.1);
            }
            for ($i = 0; $i < 3; $i++) {
                $this->signal(1);
            }
        }
    }
}

class LampCommandFactory
{
    public function factory($type, Lamp $lamp)
    {
        if ($type == 'ON') {
            return new TurnOnCommand($lamp);
        }
        if ($type == 'OFF') {
            return new TurnOffCommand($lamp);
        }

        if ($type == 'SOS') {
            return new SosCommand($lamp);
        }

        throw new RuntimeException('Cannot produce command with type ' . $type);
    }
}

class Lamp
{
    public function turnOn()
    {
        echo "I'm bright and cheerful light.\n";
    }

    public function turnOff()
    {
        echo "I am quiet and peaceful shadow\n";
    }
}

$lamp = new Lamp();
$factory = new LampCommandFactory();
$factory->factory($argv[1], $lamp)->execute();