server {
    listen 80;
    server_name _;
    root /usr/share/nginx/html;
    index index.html;

    # 启用 gzip 压缩
    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/json application/javascript;

    # API 代理配置 - 将 /api 代理到后端服务器
    location /api {
        proxy_pass https://api.duiduiedu.com;
        proxy_set_header Host api.duiduiedu.com;
        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;
        
        # 处理跨域
        add_header Access-Control-Allow-Origin * always;
        add_header Access-Control-Allow-Methods 'GET, POST, PUT, DELETE, OPTIONS' always;
        add_header Access-Control-Allow-Headers 'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range,Authorization' always;
        
        # 处理预检请求
        if ($request_method = 'OPTIONS') {
            add_header Access-Control-Allow-Origin *;
            add_header Access-Control-Allow-Methods 'GET, POST, PUT, DELETE, OPTIONS';
            add_header Access-Control-Allow-Headers 'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type,Range,Authorization';
            add_header Access-Control-Max-Age 1728000;
            add_header Content-Type 'text/plain; charset=utf-8';
            add_header Content-Length 0;
            return 204;
        }
        
        # SSL 相关配置
        proxy_ssl_verify off;
        proxy_ssl_server_name on;
        
        # 超时配置
        proxy_connect_timeout 60s;
        proxy_send_timeout 60s;
        proxy_read_timeout 60s;
    }

    # 前端静态资源
    location / {
        try_files $uri $uri/ /index.html;
        
        # 静态资源缓存配置
        location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
            expires 1y;
            add_header Cache-Control "public, immutable";
        }
    }

    # 错误页面
    error_page 404 /index.html;
}