<?php

interface UserRepository
{
    function add(User $user);
}

###############

class DoctrineUserRepository implements UserRepository
{
    private $doctrine;

    public function __construct(Registry $doctrine)
    {
        $this->doctrine = $doctrine;
    }

    function add(User $user)
    {
        $this->doctrine->getEntityManager()->getConnection()->beginTransaction();

        try{
            $this->doctrine->getEntityManager()->persist($user);
            $this->doctrine->getEntityManager()->flush();
            $this->doctrine->getEntityManager()->commit();
        } catch(\Exception $e){
            $this->doctrine->getEntityManager()->rollback();
            $this->doctrine->getEntityManager()->close();

            throw $e;
        }
    }
}

###############

class User
{
    private $username;

    private $password;

    public function __construct($username)
    {
        $this->username = $username;
    }

    public static function create(array $data)
    {
        $user = new User;
        $user->username = $data['username'];
        $user->password = $data['password'];

        return $user;
    }
}

#################


interface UserFactory
{
    public function createUser(array $data);
}

class SecuredPasswordUserFactory implements UserFactory
{
    public function createUser(array $data)
    {
        $user = new User($data['username']);
        $user->setPassword(md5($data['password']));

        return $user;
    }
}

################


class RegistrationService
{
    private $users;

    private $userFactory;

    public function __construct(UserRepository $users, UserFactory $factory)
    {
        $this->users = $users;
        $this->userFactory = $factory;
    }

    public function register(array $data)
    {
        $user = $this->userFactory->createUser($data);

        try {
            $this->users->add($user);
        } catch (\Exception $e) {
            return false;
        }

        return true;
    }
}