package com.ruoyi.im.config;

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;

/**
 * 获取IP地址工具类
 */
public class IpUtils {

    /**
     * 获取客户端真实IP地址
     * 考虑了反向代理、负载均衡等情况
     */
    public static String getClientIp(HttpServletRequest request) {
        String ip = request.getHeader("X-Forwarded-For");

        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("HTTP_CLIENT_IP");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("HTTP_X_FORWARDED_FOR");
        }
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getRemoteAddr();
        }

        // 对于通过多个代理的情况，第一个IP为客户端真实IP
        if (ip != null && ip.contains(",")) {
            ip = ip.split(",")[0].trim();
        }

        // 处理本地地址
        if ("0:0:0:0:0:0:0:1".equals(ip) || "127.0.0.1".equals(ip)) {
            // 根据实际网卡取本机配置的IP
            ip = getLocalIp();
        }

        return ip;
    }

    /**
     * 获取本机IP地址
     */
    public static String getLocalIp() {
        try {
            return InetAddress.getLocalHost().getHostAddress();
        } catch (UnknownHostException e) {
            return "127.0.0.1";
        }
    }

    /**
     * 获取请求的完整URL
     */
    public static String getRequestUrl(HttpServletRequest request) {
        StringBuffer url = request.getRequestURL();
        String queryString = request.getQueryString();
        if (queryString != null) {
            url.append("?").append(queryString);
        }
        return url.toString();
    }

    /**
     * 获取用户代理信息
     */
    public static String getUserAgent(HttpServletRequest request) {
        return request.getHeader("User-Agent");
    }

    /**
     * 获取请求方法
     */
    public static String getMethod(HttpServletRequest request) {
        return request.getMethod();
    }
}