// ❌ بدون DI — تبعية صلبة
class UserController
{
    private UserService $service;
    public function __construct()
    {
        $this->service = new UserService(new MySQLUserRepository());
    }
}

// ✅ مع DI — تُحقن التبعيات
class UserController
{
    public function __construct(
        private UserService $service
    ) {}
}

$this->app->bind(PaymentGateway::class, StripeGateway::class);
$this->app->singleton(HelpSpot\API::class, function ($app) {
    return new HelpSpot\API($app->config->get('helpspot.api_key'));
});

$this->app->bind(PaymentGateway::class, StripeGateway::class);

// تغيير مزود الدفع بتغيير سطر واحد
$this->app->bind(PaymentGateway::class, PayPalGateway::class);

$this->app->when(PhotoController::class)
    ->needs(Filesystem::class)
    ->give(function () { return Storage::disk('local'); });

$this->app->when(VideoController::class)
    ->needs(Filesystem::class)
    ->give(function () { return Storage::disk('s3'); });

class AppServiceProvider extends ServiceProvider
{
    public function register(): void
    {
        $this->app->bind(PaymentGateway::class, StripeGateway::class);
    }

    public function boot(): void
    {
        // بعد تسجيل كل المزودين
    }
}

Cache::get('key');
// يعادل:
$app->make('cache')->get('key');