feat: initial foundation for collaborative canteen ordering system in vanilla PHP

app/Core/Controller.php

@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Core;
+
+use App\Core\Http\Request;
+use App\Core\Http\Response;
+
+abstract class Controller
+{
+    protected function render(string $view, array $data = [], ?string $layout = 'layouts/main'): string
+    {
+        return View::render($view, $data, $layout);
+    }
+
+    protected function json(mixed $data, int $statusCode = 200): Response
+    {
+        $response = new Response();
+        return $response->json($data, $statusCode);
+    }
+
+    protected function redirect(string $url, ?string $flashSuccess = null, ?string $flashError = null): Response
+    {
+        if ($flashSuccess) {
+            View::setFlash('success', $flashSuccess);
+        }
+        if ($flashError) {
+            View::setFlash('error', $flashError);
+        }
+
+        $response = new Response();
+        return $response->redirect($url);
+    }
+
+    protected function validateCsrf(Request $request): bool
+    {
+        if (session_status() === PHP_SESSION_NONE) {
+            session_start();
+        }
+
+        $token = $request->post('_csrf') ?: $request->getHeader('X-CSRF-Token');
+        $sessionToken = $_SESSION['csrf_token'] ?? null;
+
+        return $token && $sessionToken && hash_equals($sessionToken, $token);
+    }
+}