初始化版本

auth.php

@@ -0,0 +1,30 @@
+<?php
+// 简易会话认证
+session_start();
+require_once __DIR__ . '/config.php';
+
+function is_logged_in(): bool {
+  return !empty($_SESSION['logged_in']);
+}
+
+function require_login(): void {
+  if (!is_logged_in()) {
+    $target = 'login.php';
+    if (!headers_sent()) {
+      header('Location: ' . $target);
+    } else {
+      echo '<script>location.replace("' . $target . '")</script>';
+      echo '<noscript><meta http-equiv="refresh" content="0;url=' . $target . '"></noscript>';
+    }
+    exit;
+  }
+}
+
+function require_api_auth(): void {
+  if (!is_logged_in()) {
+    header('Content-Type: application/json; charset=utf-8');
+    http_response_code(401);
+    echo json_encode(['error' => 'unauthorized']);
+    exit;
+  }
+}