server {
    listen 80;
    listen [::]:80;
    server_name _;

    root /usr/share/nginx/html;
    index index.html;

    location = /healthz {
        default_type text/plain;
        return 200 "ok\n";
    }

    # SPA 入口每次重新校验，避免发布后浏览器继续运行旧资源清单。
    location = /index.html {
        add_header Cache-Control "no-store, no-cache, must-revalidate" always;
        add_header Pragma "no-cache" always;
        add_header Expires "0" always;
    }

    # Vite 产物文件名带内容哈希，可安全长期缓存。
    location /assets/ {
        try_files $uri =404;
        add_header Cache-Control "public, max-age=31536000, immutable" always;
    }

    # 前端统一请求 /api，保持原始路径转发给 Gateway。
    location /api/ {
        client_max_body_size 55m;
        proxy_pass ${API_UPSTREAM};
        proxy_http_version 1.1;
        proxy_set_header Host $proxy_host;
        proxy_set_header X-Real-IP $remote_addr;
        proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for;
        proxy_set_header X-Forwarded-Proto $scheme;
    }


    # 支持 Vue Router history 路由直接刷新。
    location / {
        add_header Cache-Control "no-store, no-cache, must-revalidate" always;
        try_files $uri $uri/ /index.html;
    }
}