Facade Pattern Example #php #design-patterns #facade-pattern

facade-pattern.php

<?php

const BOOT_ADDRESS = 0xd34db33f;
const BOOT_SECTOR = 0x7c;
const SECTOR_SIZE = 4096;

interface IComputer
{
    public function powerOn();
    public function powerOff();
}

class Memory
{
    public function load($address, $data)
    {
        printf("load 0x%x, 0x%x\n", $address, $data);
    }
}

class HardDrive
{
    public function read($lba, $size)
    {
        printf("read 0x%x, 0x%x\n", $lba, $size);
        return 0x80;
    }
}

class Cpu
{
    public function jump($position)
    {
        printf("jmp 0x%x\n", $position);
    }

    public function exec()
    {
        echo "exec\n";
    }
}

class ComputerFacade implements IComputer
{
    protected $cpu;
    protected $ram;
    protected $hdd;

    public function __construct()
    {
        $this->cpu = new Cpu;
        $this->ram = new Memory;
        $this->hdd = new HardDrive;
    }

    public function powerOn()
    {
        $this->ram->load(BOOT_ADDRESS, $this->hdd->read(BOOT_SECTOR, SECTOR_SIZE));
        $this->cpu->jump(BOOT_ADDRESS);
        $this->cpu->exec();
    }

    public function powerOff()
    {
    }
}

$computer = new ComputerFacade;
$computer->powerOn();