domovoy/app/Services/AuthService.php

<?php

declare(strict_types=1);

namespace Domovoy\Services;

use Domovoy\Models\User;
use Domovoy\Repositories\UserRepository;

class AuthService
{
    private UserRepository $userRepository;

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

    public function authenticate(string $username, string $password): ?User
    {
        $user = $this->userRepository->findByUsername($username);
        if ($user === null) {
            return null;
        }

        if (!password_verify($password, $user->passwordHash)) {
            return null;
        }

        return $user;
    }

    public function createUser(string $username, string $password): User
    {
        if ($this->userRepository->findByUsername($username) !== null) {
            throw new \RuntimeException("User '{$username}' already exists");
        }

        $user = new User();
        $user->username = $username;
        $user->passwordHash = password_hash($password, PASSWORD_ARGON2ID);
        $user->createdAt = new \DateTimeImmutable();
        $user->updatedAt = new \DateTimeImmutable();

        $this->userRepository->save($user);
        return $user;
    }

    public function getUserCount(): int
    {
        return $this->userRepository->count();
    }
}