Implement basic database access and login

src/Common/UserHelper.php

@@ -0,0 +1,33 @@
+<?php
+declare(strict_types=1);
+
+namespace MailAccountAdmin\Common;
+
+use http\Exception\RuntimeException;
+use MailAccountAdmin\Models\AdminUser;
+use MailAccountAdmin\Repositories\AdminUserRepository;
+
+class UserHelper
+{
+    /** @var AdminUserRepository */
+    private $adminUserRepository;
+
+    public function __construct(AdminUserRepository $adminUserRepository)
+    {
+        $this->adminUserRepository = $adminUserRepository;
+    }
+
+    public function isLoggedIn(): bool
+    {
+        return !empty($_SESSION['username']);
+    }
+
+    public function getCurrentUser(): AdminUser
+    {
+        $username = $_SESSION['username'] ?? null;
+        if (empty($username)) {
+            throw new RuntimeException('Not logged in!');
+        }
+        return $this->adminUserRepository->getUserByName($username);
+    }
+}