Php facade design pattern simple and complete example with dependency injection

Classes.php

<?php
class Validate implements ValidateInterface
{
	public function isValid(array $data)
	{
		return true;
	}
}

class Auth implements AuthInterface
{
	public function login($username, $password)
	{
		return true;
	}
}

class User implements UserInterface
{
	public function create(array $data)
	{
		return true;
	}
}

class Mail implements MailInterface
{
	public function to($to)
	{
		return $this;
	}

	public function subject($subject)
	{
		return $this;
	}

	public function send()
	{
		return true;
	}
}

// Create instance of classes
$validate = new Validate();
$user = new User();
$auth = new Auth();
$mail = new Mail();

Interfaces.php

<?php
interface ValidateInterface
{
	public function isValid(array $data);
}

interface AuthInterface
{
	public function login($username, $password);
}

interface UserInterface
{
	public function create(array $data);
}

interface MailInterface
{
	public function to($to);
	public function subject($subject);
	public function send();
}

SignUpFacade.php

<?php
/**
* Facade pattern class
*
* @author altayalp <altayalp@gmail.com>
*/
class SignUpFacade
{

	private $validate;
	private $user;
	private $auth;
	private $mail;

	public function __construct(ValidateInterface $validate, UserInterface $user, AuthInterface $auth, MailInterface $mail)
	{
		$this->validate = $validate;
		$this->user = $user;
		$this->auth = $auth;
		$this->mail = $mail;
	}

	public function signUpUser($userName, $userPass, $userMail)
	{
		if ($this->validate->isValid(['name' => $userName, 'password' =>$userPass, 'mail' => $userMail])) {
			$this->user->create(['name' => $userName, 'password' =>$userPass, 'mail' => $userMail]);
			$this->auth->login($userName, $userPass);
			$this->mail->to($userMail)->subject('Welcome')->send();
		}
	}

}

witFacade.php

<?php
// Simple sign up process with facade pattern
$facade = new SignUpFacade($validate, $user, $auth, $mail);
$facade->signUpUser($userName, $userPass, $userMail);

withoutFacade.php

<?php
// Simple sign up process without facade pattern

if ($validate->isValid(['name' => $userName, 'password' =>$userPass, 'mail' => $userMail])) {

	$user->create(['name' => $userName, 'password' =>$userPass, 'mail' => $userMail]);

	$auth->login($userName, $userPass);

	$mail->to($userMail)->subject('Welcome')->send();

}

helpful, thank you!