package com.mir4updater.backend.utils;

import jakarta.servlet.http.HttpServletRequest;

public class IpUtils {
        public static String getClientIpAddress(HttpServletRequest request) {
            String[] headersToCheck = {
                    "X-Forwarded-For",
                    "Proxy-Client-IP",
                    "WL-Proxy-Client-IP",
                    "HTTP_CLIENT_IP",
                    "HTTP_X_FORWARDED_FOR"
            };

            String ip = null;
            for (String header : headersToCheck) {
                ip = request.getHeader(header);
                if (isValidIp(ip)) {
                    break;
                }
            }

            // 处理多IP情况
            if (ip != null && ip.contains(",")) {
                ip = ip.split(",")[0].trim();
            }

            // 回退到默认方法
            if (!isValidIp(ip)) {
                ip = request.getRemoteAddr();
            }

            // 处理IPv6本地地址
            if ("0:0:0:0:0:0:0:1".equals(ip)) {
                ip = "127.0.0.1";
            }

            return ip;
        }

        private static boolean isValidIp(String ip) {
            return ip != null && !ip.isEmpty() && !"unknown".equalsIgnoreCase(ip);
        }
}