server {
    listen 7878;
    server_name _;
    root /app/frontend/dist;
    index index.html;

    # 静态内容优先走前端
    location / {
        try_files $uri $uri/ /index.html @backend;
        add_header Cache-Control "no-cache, must-revalidate";
    }

    # 后端 API 代理
    location /api {
        proxy_pass http://127.0.0.1:5000;
        proxy_set_header Host $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;
    }

    # 兜底转发到后端（短链跳转）
    location @backend {
        proxy_pass http://127.0.0.1:5000;
        proxy_set_header Host $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;
    }

    # 静态资源缓存策略
    location ~* \.(jpg|jpeg|png|gif|ico|css|js|svg)$ {
        expires 1y;
        add_header Cache-Control "public, immutable";
    }
}