// public/index.php
<?php
define('ATOMIC_START', true);
require_once __DIR__ . '/../bootstrap/app.php';
$application->run();

// config/database.php
return [
    'default'     => 'mysql',
    'connections' => [
        'mysql' => [
            'driver'   => 'mysql',
            'host'     => '127.0.0.1',
            'database' => 'atomic',
            'username' => 'root',
            'password' => '',
            'charset'  => 'utf8mb4',
        ],
    ],
];

$application = App::instance($atomic)
    ->prefly()                  // Verify PHP version, extensions, directory permissions
    ->registerLogger()          // Initialize structured logging
    ->registerExceptionHandler()
    ->registerLocales()         // Set up i18n
    ->registerMiddleware()      // Load middleware aliases
    ->registerRoutes()          // Load route files by request type
    ->registerPlugins()         // Activate registered plugins
    ->initSession()             // Start session (lazy: only if cookie exists)
    ->setDB()                   // Establish database connection
    ->registerUserProvider();   // Wire authentication backend

// routes/web.php
$f3->route('GET /dashboard', 'App\Http\Controllers\DashboardController->index');
$f3->route('POST /contact', 'App\Http\Controllers\ContactController->submit');

// config/middleware.php
return [
    'auth'  => App\Http\Middleware\Authenticate::class,
    'admin' => App\Http\Middleware\RequireAdmin::class,
];

// Usage with parameters
$middleware->forRoute('/admin/*', ['auth', 'admin']);
$middleware->forRoute('/store/*', ['store:banned']);  // Parameterized: Store('banned')

use Engine\Atomic\Core\Middleware\MiddlewareInterface;

class Authenticate implements MiddlewareInterface
{
    public function handle(\Base $atomic): bool
    {
        // Return true to continue, false to abort
        return Guard::is_authenticated();
    }
}

use Engine\Atomic\App\Controller;

class DashboardController extends Controller
{
    public function index(\Base $f3): void
    {
        // Middleware is enforced automatically
        $this->render('dashboard/index.html');
    }
}

use Engine\Atomic\App\Model;

class User extends Model
{
    protected function get_rules(): array
    {
        return [
            'email'    => ['rule' => Rule::EMAIL, 'required' => true],
            'uuid'     => ['rule' => Rule::UUID_V4, 'required' => true],
            'password' => ['rule' => Rule::PASSWORD_ENTROPY, 'min_entropy' => 40],
        ];
    }
}

use Engine\Atomic\Auth\Auth;

// Password-based login
$user = Auth::instance()->login_with_secret(
    ['email' => $email],
    $password
);

// OAuth login
$url = Auth::instance()->google()->getLoginUrl();
$userId = Auth::instance()->google()->handleCallback($code, $state);

// Session management
$currentUser = Auth::instance()->get_current_user();
Auth::instance()->logout();
Auth::instance()->kill_all_sessions($userId);

// Rate limiting (dual: IP + credential)
$blocked = Auth::instance()->check_rate_limit(['email' => $email], 'login');

// Admin impersonation
Auth::instance()->impersonate_user($targetUuid);
Auth::instance()->stop_impersonation();

use Engine\Atomic\Queue\Managers\Manager;

Manager::instance()->push('email', [
    'to'      => 'user@example.com',
    'subject' => 'Welcome',
]);

// routes/schedule.php
$scheduler->call(function () {
    // Cleanup expired sessions
})->daily()->at('03:00')->timezone('UTC');

use Engine\Atomic\Event\Event;

Event::instance()->on('user.created', function ($data) {
    // Send welcome email
}, priority: 10);

Event::instance()->emit('user.created', ['user' => $user]);

use Engine\Atomic\Hook\Hook;

Hook::instance()->add_action('after_login', function ($user) {
    // Track login
});

$title = Hook::instance()->apply_filters('page_title', $rawTitle);

use Engine\Atomic\Tools\Transient;

// Store a value with TTL
Transient::instance()->set('stats', $data, ttl: 3600);
$cached = Transient::instance()->get('stats');

// Cascade: tries Redis → Memcached → Database
$cache = CacheManager::instance()->cascade();

use Engine\Atomic\Lang\I18n;

$i18n = I18n::instance();
echo $i18n->t('welcome_message');                // Simple translation
echo $i18n->tn('item', 'items', $count);         // Pluralization
echo $i18n->tx('menu', 'navigation');             // Contextual translation
echo $i18n->url('/about', 'fr');                  // Localized URL: /fr/about