package com.ruoshui.core.util;

import javax.servlet.http.HttpServletRequest;
import java.net.*;
import java.util.Enumeration;

public class IPUtil {

    public static String getLocalIP() throws SocketException {
        String localIP = null;
        Enumeration allNetInterfaces = NetworkInterface.getNetworkInterfaces();
        InetAddress ip = null;
        while (allNetInterfaces.hasMoreElements()) {
            NetworkInterface netInterface = (NetworkInterface) allNetInterfaces.nextElement();
            Enumeration addresses = netInterface.getInetAddresses();
            while (addresses.hasMoreElements()) {
                ip = (InetAddress) addresses.nextElement();
                if (ip != null && ip instanceof Inet4Address) {
                    localIP = ip.getHostAddress();
                    if (!"127.0.0.1".equalsIgnoreCase(localIP)) {
                        return localIP;
                    }
                }
            }
        }
        return localIP;
    }

    /**
     * 获取当前网络ip
     * @param request
     * @return
     */
    public static String getIpAddr(HttpServletRequest request) {
        String ipAddress = request.getHeader("x-forwarded-for");
        if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("Proxy-Client-IP");
        }
        if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getHeader("WL-Proxy-Client-IP");
        }
        if (ipAddress == null || ipAddress.length() == 0 || "unknown".equalsIgnoreCase(ipAddress)) {
            ipAddress = request.getRemoteAddr();
            if (ipAddress.equals("127.0.0.1") || ipAddress.equals("0:0:0:0:0:0:0:1")) {
                //根据网卡取本机配置的IP
                InetAddress inet = null;
                try {
                    inet = InetAddress.getLocalHost();
                } catch (UnknownHostException e) {
                    e.printStackTrace();
                }
                ipAddress = inet.getHostAddress();
            }
        }
        //对于通过多个代理的情况，第一个IP为客户端真实IP,多个IP按照','分割
        if (ipAddress != null && ipAddress.length() > 15) { //"***.***.***.***".length() = 15
            if (ipAddress.indexOf(",") > 0) {
                ipAddress = ipAddress.substring(0, ipAddress.indexOf(","));
            }
        }
        return ipAddress;
    }
}
