package com.app.mvc.util;

import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;

import javax.servlet.http.HttpServletRequest;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.InetAddress;
import java.net.NetworkInterface;
import java.net.UnknownHostException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/**
 * Created by jimin on 15/11/5.
 */
@Slf4j
public class IpUtil {

    public final static String ERROR_IP = "127.0.0.1";

    public final static Pattern pattern = Pattern.
            compile("(2[5][0-5]|2[0-4]\\d|1\\d{2}|\\d{1,2})\\.(25[0-5]|2[0-4]\\d|1\\d{2}|\\d{1,2})\\.(25[0-5]|2[0-4]\\d|1\\d{2}|\\d{1,2})\\.(25[0-5]|2[0-4]\\d|1\\d{2}|\\d{1,2})");

    /**
     * 取外网IP
     *
     * @param request
     * @return
     */
    public static String getRemoteIp(HttpServletRequest request) {
        String ip = request.getHeader("x-real-ip");
        if (ip == null) {
            ip = request.getRemoteAddr();
        }

        //过滤反向代理的ip
        String[] stemps = ip.split(",");
        if (stemps != null && stemps.length >= 1) {
            //得到第一个IP，即客户端真实IP
            ip = stemps[0];
        }

        ip = ip.trim();
        if (ip.length() > 23) {
            ip = ip.substring(0, 23);
        }

        return ip;
    }

    /**
     * 获取用户的真实ip
     *
     * @param request
     * @return
     */
    public static String getUserIP(HttpServletRequest request) {

        // 优先取X-Real-IP
        String ip = request.getHeader("X-Real-IP");
        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getHeader("x-forwarded-for");
        }

        if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
            ip = request.getRemoteAddr();
            if ("0:0:0:0:0:0:0:1".equals(ip)) {
                ip = ERROR_IP;
            }
        }

        if ("unknown".equalsIgnoreCase(ip)) {
            ip = ERROR_IP;
            return ip;
        }

        int pos = ip.indexOf(',');
        if (pos >= 0) {
            ip = ip.substring(0, pos);
        }

        return ip;
    }

    public static String getLastIpSegment(HttpServletRequest request) {
        String ip = getUserIP(request);
        if (ip != null) {
            ip = ip.substring(ip.lastIndexOf('.') + 1);
        } else {
            ip = "0";
        }
        return ip;
    }

    public static boolean isValidIP(HttpServletRequest request) {
        String ip = getUserIP(request);
        return isValidIP(ip);
    }

    /**
     * 判断我们获取的ip是否是一个符合规则ip
     *
     * @param ip
     * @return
     */
    public static boolean isValidIP(String ip) {
        if (StringUtils.isEmpty(ip)) {
            log.debug("ip is null. valid result is false");
            return false;
        }

        Matcher matcher = pattern.matcher(ip);
        boolean isValid = matcher.matches();
        log.debug("valid ip:" + ip + " result is: " + isValid);
        return isValid;
    }

    public static String getLastServerIpSegment() {
        String ip = getServerIP();
        if (ip != null) {
            ip = ip.substring(ip.lastIndexOf('.') + 1);
        } else {
            ip = "0";
        }
        return ip;
    }

    public static String getServerIP() {
        InetAddress inet;
        try {
            inet = InetAddress.getLocalHost();
            String hostAddress = inet.getHostAddress();
            return hostAddress;
        } catch (UnknownHostException e) {
            e.printStackTrace();
        }
        return "127.0.0.1";
    }

    /**
     * 获取mac地址
     *
     * @param ip
     * @return
     */
    public static String getMACAddress(String ip) {
        String line = "";
        String macAddress = "";
        final String MAC_ADDRESS_PREFIX = "MAC";
        final String LOOPBACK_ADDRESS = "127.0.0.1";

        try {
            //如果为127.0.0.1,则获取本地MAC地址。
            if (LOOPBACK_ADDRESS.equals(ip)) {
                InetAddress inetAddress = InetAddress.getLocalHost();
                //貌似此方法需要JDK1.6。
                NetworkInterface networkInterface = NetworkInterface.getByInetAddress(inetAddress);
                byte[] mac = networkInterface.getHardwareAddress();
                if (networkInterface == null || mac == null) {
                    return "127.0.0.1";
                }

                //下面代码是把mac地址拼装成String
                StringBuilder sb = new StringBuilder();
                for (int i = 0; i < mac.length; i++) {
                    if (i != 0) {
                        sb.append("-");
                    }
                    //mac[i] & 0xFF 是为了把byte转化为正整数
                    String s = Integer.toHexString(mac[i] & 0xFF);
                    sb.append(s.length() == 1 ? 0 + s : s);
                }
                //把字符串所有小写字母改为大写成为正规的mac地址并返回
                macAddress = sb.toString().trim().toUpperCase();
                return macAddress;
            }
            //获取非本地IP的MAC地址
            Process p = Runtime.getRuntime().exec("nbtstat -A " + ip);
            InputStreamReader isr = new InputStreamReader(p.getInputStream());
            BufferedReader br = new BufferedReader(isr);
            while ((line = br.readLine()) != null) {
                if (line != null) {
                    int index = line.indexOf(MAC_ADDRESS_PREFIX);
                    if (index != -1) {
                        index = line.indexOf("=");
                        macAddress = line.substring(index + 1).trim().toUpperCase();
                    }
                }
            }
            br.close();
        } catch (IOException e) {
            log.info("get mac address error, ip: " + ip);
            return "";
        }
        return macAddress;
    }
}