server {
    listen 80;
    server_name _;

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

    # Gzip 壓縮
    gzip on;
    gzip_vary on;
    gzip_min_length 1024;
    gzip_types text/plain text/css text/xml text/javascript application/x-javascript application/xml+rss application/javascript application/json;

    # SPA 路由支援
    location / {
        try_files $uri $uri/ /index.html;
        add_header Cache-Control "no-cache, no-store, must-revalidate";
    }

    # 靜態資源快取
    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
        expires 1y;
        add_header Cache-Control "public, immutable";
    }

    # 代理 API 請求到後端（如果前後端在同一網路）
    location /api {
        proxy_pass http://backend:8000;
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection 'upgrade';
        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;
        proxy_cache_bypass $http_upgrade;
        proxy_read_timeout 300s;
    }
}