upstream backend {
    server backend:8080;
}

upstream frontend {
    server frontend:3000;
}

server {
    listen 80;
    server_name localhost;
    
    # 安全头
    add_header X-Frame-Options "SAMEORIGIN" always;
    add_header X-XSS-Protection "1; mode=block" always;
    add_header X-Content-Type-Options "nosniff" always;
    add_header Referrer-Policy "no-referrer-when-downgrade" always;
    add_header Content-Security-Policy "default-src 'self' http: https: data: blob: 'unsafe-inline'" always;

    location /sitemap.xml {
        proxy_pass http://backend/api$request_uri;
        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;
    }
    
    location ~ ^/sitemap-([0-9]+)\.xml$ {
        proxy_pass http://backend/api$request_uri;
        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;
    }
    
        # API 路由 - 所有 /api/ 开头的请求转发到后端
    location /api/ {
        proxy_pass http://backend;
        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;
        
        # 超时设置
        proxy_connect_timeout 60s;
        proxy_send_timeout 60s;
        proxy_read_timeout 60s;
        
        # 缓冲设置
        proxy_buffering on;
        proxy_buffer_size 4k;
        proxy_buffers 8 4k;
        
        # 错误处理
        proxy_intercept_errors on;
        error_page 502 503 504 /50x.html;
    }
    
    
    location ^~ /uploads/ {
        proxy_pass http://backend/uploads/;
        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;
        
        expires 1y;
        add_header Cache-Control "public, immutable";

        add_header Access-Control-Allow-Origin "*";
        add_header Access-Control-Allow-Methods "GET, OPTIONS";
        add_header Access-Control-Allow-Headers "Origin, Content-Type, Accept";
    }


    # 静态文件路由 - 直接转发到前端
    location ~* \.(js|css|png|jpg|jpeg|gif|ico|svg|woff|woff2|ttf|eot)$ {
        proxy_pass http://frontend;
        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;
        
        # 缓存设置
        expires 1y;
        add_header Cache-Control "public, immutable";
    }

    # 微信公众号验证文件路由 - 根目录的TXT文件直接访问后端uploads目录
    location ~ ^/[^/]+\.txt$ {
        # 检查文件是否存在于uploads目录
        set $uploads_path /uploads$uri;
        if (-f $uploads_path) {
            proxy_pass http://backend;

            # 缓存设置
            expires 1h;
            add_header Cache-Control "public";

            # 允许跨域访问
            add_header Access-Control-Allow-Origin "*";
            add_header Access-Control-Allow-Methods "GET, OPTIONS";
            add_header Access-Control-Allow-Headers "Origin, Content-Type, Accept";
            break;
        }
        # 如果文件不存在，返回404
        return 404;
    }

    # 健康检查
    location /health {
        proxy_pass http://backend/health;
        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;
    }

    # 默认路由 - 所有其他请求转发到前端
    location / {
        proxy_pass http://frontend;
        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;
        
        # WebSocket 支持
        proxy_http_version 1.1;
        proxy_set_header Upgrade $http_upgrade;
        proxy_set_header Connection "upgrade";
        
        # 超时设置
        proxy_connect_timeout 60s;
        proxy_send_timeout 60s;
        proxy_read_timeout 60s;
        
        # 缓冲设置
        proxy_buffering off;
        
        # 错误处理
        proxy_intercept_errors on;
        error_page 502 503 504 /50x.html;
    }

    # 错误页面
    error_page 500 502 503 504 /50x.html;
    location = /50x.html {
        root /usr/share/nginx/html;
    }
}