Куда поместить код: статический метод или сервис?

class User extends ActiveRecord
{
    public static function isPasswordResetTokenValid($token)
    {
        if (empty($token)) {
            return false;
        }
        $timestamp = (int) substr($token, strrpos($token, '_') + 1);
        $expire = Yii::$app->params['user.passwordResetTokenExpire'];
        return $timestamp + $expire >= time();
    }
 
    public function generatePasswordResetToken()
    {
        $this->password_reset_token = Yii::$app->security->generateRandomString() . '_' . time();
    }
 
    ...
}

namespace Domain\Service;
 
interface PasswordResetTokenizer
{
    public function generate();
    public function validate($token);
}

namespace Application\Service;
 
use Domain\Repository\UserRepository;
use Domain\Service\PasswordHasher;
...
 
class UserService
{
    private $users;
    private $hasher;
    private $tokenizer;
    private $dispatcher;
 
    public function __construct(
        UserRepository $users,
        PasswordHasher $hasher,
        PasswordResetTokenizer $tokenizer,
        EventDispatcher $dispatcher
    )
    {
        $this->users = $users;
        $this->hasher = $hasher;
        $this->tokenizer = $tokenizer;
        $this->dispatcher = $dispatcher;
    }
 
    public function requestPasswordReset($email)
    {
        $user = $this->users->getByEmail($email);
        $user->requestPasswordReset($this->tokenizer->generate());
        $this->users->save($user);
        $this->dispatcher->dispatch($user->releaseEvents());
    }
 
    public function confirmPasswordReset($token, $pasword)
    {
        if (!$this->tokenizer->validate($token)) {
            throw new \DomainException('Token is not valid.');
        }
        $user = $this->users->getByPasswordResetToken($token);
        $user->changePassword($this->hasher->hash($pasword));
        $this->users->save($user);
        $this->dispatcher->dispatch($user->releaseEvents());
    }
    
    ...
}

namespace Infrastructre\Service;
 
use yii\base\Secuity;
 
class YiiPasswordResetTokenizer implements PasswordResetTokenizer
{
    private $security;
    private $timeout;
 
    public function __construct(Security $security, $timeout)
    {
        $this->security = $security;
        $this->timeout = $timeout;
    }   
 
    public function generate()
    {
         return $this->security->generateRandomString() . '_' . time();
    }
 
    public function validate($token)
    {
        if (empty($token)) {
            return false;
        }
        $timestamp = (int) substr($token, strrpos($token, '_') + 1);
        return $timestamp + $this->timeout >= time();
    }
}

Yii::$container->setSingleton('Domain\Service\PasswordResetTokenizer', function() {
    return new YiiPasswordResetTokenizer(
        Yii::$app->security,
        Yii::$app->params['user.passwordResetTokenExpire']        
    );
});

class UserController
{
    private $service;
 
    public function __construct($id, $module, UserService $service, $config = [])
    {
        $this->service = $service;
        parent::__construct($id, $module, $config);
    }
 
    ...
}

$this->service->confirmPasswordReset($token, $form->password);

class UserService
{
    public function requestPasswordReset($email)
    {
        $user = $this->users->getByEmail($email);
        $user->requestPasswordReset($this->tokenizer);
        $this->users->save($user);
        $this->dispatcher->dispatch($user->releaseEvents());
    }
}

class User
{
    public function requestPasswordReset(PasswordResetTokenizer $tokenizer)
    {
        if ($this->hasValidPasswordResetToken($tokenizer)) {
            throw new \DomainException('Token is already sent.');
        }
        $token = $tokenizer->generate();
        $this->passwordResetToken = $token;
        $this->recordEvent(new PasswordResetRequested($this->id, $this->email, $token));
    }
 
    private function hasValidPasswordResetToken(PasswordResetTokenizer $tokenizer)
    {
        return $this->passwordResetToken !== null && $tokenizer->validate($this->passwordResetToken);
    }
 
    ...
}