add auth middleware

app/Auth/AuthMiddleware.php

@@ -0,0 +1,84 @@
+<?php
+
+namespace App\Auth;
+
+use App\User\UserRepository;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+use Psr\Http\Server\MiddlewareInterface;
+use Psr\Http\Server\RequestHandlerInterface;
+use Slim\Psr7\Response;
+
+class AuthMiddleware implements MiddlewareInterface
+{
+    public const COOKIE_NAME = 'auth_token';
+
+    public function __construct(
+        private SessionRepository $sessionRepo,
+        private UserRepository $userRepo,
+        private Clock $clock,
+    ) {}
+
+    public function process(
+        ServerRequestInterface $request,
+        RequestHandlerInterface $handler,
+    ): ResponseInterface {
+        $cookies = $request->getCookieParams();
+        $token = $cookies[self::COOKIE_NAME] ?? null;
+
+        if ($token === null) {
+            return $this->unauthorized($request);
+        }
+
+        $session = $this->sessionRepo->findByToken($token);
+        if ($session === null) {
+            return $this->unauthorized($request);
+        }
+
+        if ($session->isExpired($this->clock->now())) {
+            $this->sessionRepo->deleteByToken($token);
+            return $this->unauthorized($request);
+        }
+
+        $user = $this->userRepo->find($session->getUserId());
+        if ($user === null) {
+            return $this->unauthorized($request);
+        }
+
+        return $handler->handle(
+            $request->withAttribute('user', $user)
+        );
+    }
+
+    private function unauthorized(
+        ServerRequestInterface $request
+    ): ResponseInterface {
+        if ($this->wantsJson($request)) {
+            $response = new Response(401);
+            $response->getBody()->write(
+                json_encode(['error' => 'unauthenticated'])
+            );
+            return $response->withHeader(
+                'Content-Type',
+                'application/json'
+            );
+        }
+
+        return new Response(302)->withHeader('Location', '/login');
+    }
+
+    private function wantsJson(ServerRequestInterface $request): bool
+    {
+        $path = $request->getUri()->getPath();
+        if (str_starts_with($path, '/api/')) {
+            return true;
+        }
+
+        $accept = $request->getHeaderLine('Accept');
+        if (str_contains($accept, 'application/json')) {
+            return true;
+        }
+
+        return false;
+    }
+}