import lombok.extern.slf4j.Slf4j;
import org.apache.commons.lang3.StringUtils;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.InetAddress;
import java.net.MulticastSocket;
import java.net.UnknownHostException;
import java.nio.ByteBuffer;
import java.util.Collections;
/**
 * @Title: 发送魔术包：实现电脑远程开机(WOL)
 * @ClassName: com.devicemag.core.utils.MagicPackageUtils.java
 * @Description:
 *
 * @Copyright 2020-2021  - Powered By 研发中心
 * @author: FLY
 * @date: 2021/1/8 9:32
 * @version V1.0
 */
@Slf4j
public class MagicPackageUtils {
    /**
     * main方法，发送UDP广播，实现远程开机，目标计算机的MAC地址为：D8-9E-F3-95-AC-74
     */
    public static void main(String[] args) {
        // 10.0.50.138  D8-9E-F3-88-B6-3C
        // 10.0.50.129  66-00-6A-8F-1D-64
        // 10.0.50.186  D8-9E-F3-95-AC-74
        // 单播
//        sendMagicPackage("10.0.50.186", "D8-9E-F3-95-AC-74");
        // 广播，需要先根据子网掩码和ip得到主机的广播地址
        String broadcastAddress=getBroadcastAddress("10.0.50.186","255.255.255.0");
        System.out.println(broadcastAddress);
    }
    /**
     * @Title: 组装魔术包数据
     * @MethodName: assembleMagicData
     * @param mac
     * @Return java.lang.String
     * @Exception
     * @Description:
     *
     * 魔术包是用16进制表示的数据包，它由固定的前缀数据以及固定重复次数的目标主机MAC地址所组成。
     *  所谓固定前缀数据即6对“FF”，所谓固定重复次数即16次，也就是说魔术包是由12个“F”加重复16次的主机MAC地址组成，例如本文所用试验机的MAC地址为“66-00-6A-8F-1D-64”，
     *  所以使该机远程开机的魔术包为：
     *         String magicPacageData = "FFFFFFFFFFFF" +
     *                 "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" +
     *                 "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" +
     *                 "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" +
     *                 "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64";
     *
     * 在Windows系统中，主机的MAC地址可以通过在命令窗口中输入“ipconfig -all”命令查看。
     *
     * @author: FLY
     * @date: 2021/1/11 18:02
     */
    private static String assembleMagicData(String mac) {
        String macR = null;
        if (mac.contains("-")) {
            macR = mac.replaceAll("-", "");
        } else if (mac.contains(":")) {
            macR = mac.replaceAll(":", "");
        }
        String repeatedStr = createRepeatedStr(macR, 16);
        String magicData = new StringBuilder("FFFFFFFFFFFF").append(repeatedStr).toString();
        return magicData;
    }
    /**
     * @Title: 远程开机
     * @MethodName: sendMagicPackage
     * @param ip
     * @param mac
     * @Return void
     * @Exception
     * @Description: 发送UDP广播，实现远程开机
     *
     * @author: FLY
     * @date: 2021/1/11 17:19
     */
    public static void sendMagicPackage(String ip, String mac) {
        log.info("【魔包远程开机】，IP地址：{}，MAC地址：{}", ip, mac);
        if (StringUtils.isBlank(ip)
                || StringUtils.isBlank(mac)) {
            return;
        }
        //端口号
        int port = 9;
        //魔术包数据
        /*String magicPacageData = "FFFFFFFFFFFF" +
                "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" +
                "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" +
                "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" +
                "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64" + "64006A8F1D64";*/
        String magicPacageData = assembleMagicData(mac);
        log.info("【魔包远程开机】，IP地址：{}，MAC地址：{}，魔术包数据：{}", ip, mac, magicPacageData);
        // mac地址转换为2进制的魔术包数据
        byte[] command = hexStr2Byte(magicPacageData);
        //广播魔术包
        try {
            //1.获取ip地址
            InetAddress address = InetAddress.getByName(ip);
            //2.获取广播socket
            MulticastSocket socket = new MulticastSocket(port);
            //3.封装数据包
            /*public DatagramPacket(byte[] buf,int length
             *      ,InetAddress address
             *      ,int port)
             * buf：缓存的命令
             * length：每次发送的数据字节数，该值必须小于等于buf的大小
             * address：广播地址
             * port：广播端口
             */
            DatagramPacket packet = new DatagramPacket(command, command.length, address, port);
            //4.发送数据
            socket.send(packet);
            //5.关闭socket
            socket.close();
        } catch (UnknownHostException e) {
            //Ip地址错误时候抛出的异常
            log.error("【魔包远程开机】异常-Ip地址错误，IP地址：{}，MAC地址：{}，异常信息：{}", ip, mac, e);
        } catch (IOException e) {
            //获取socket失败时候抛出的异常
            log.error("【魔包远程开机】异常-获取socket失败，IP地址：{}，MAC地址：{}，异常信息：{}", ip, mac, e);
        }
    }
    /**
     * @Title: 将16进制字符串转换为用byte数组表示的二进制形式
     * @MethodName: hexStr2Byte
     * @param hex
     * @Return byte[]
     * @Exception
     * @Description:
     *
     * @author: FLY
     * @date: 2021/1/11 17:22
     */
    private static byte[] hexStr2Byte(String hex) {
        ByteBuffer bf = ByteBuffer.allocate(hex.length() / 2);
        for (int i = 0; i < hex.length(); i++) {
            String hexStr = String.valueOf(hex.charAt(i));
            i++;
            hexStr += hex.charAt(i);
            byte b = (byte) Integer.parseInt(hexStr, 16);
            bf.put(b);
        }
        return bf.array();
    }
    /**
     * @Title: 将一个字符串重复n次
     * @MethodName: createRepeatedStr
     * @param seed
     * @param n
     * @Return java.lang.String
     * @Exception
     * @Description:
     *
     * @author: FLY
     * @date: 2021/1/11 17:22
     */
    private static String createRepeatedStr(String seed, int n) {
        return String.join("", Collections.nCopies(n, seed));
    }
    /**
     * @Title: 根据子网掩码和ip得到主机的广播地址
     * @MethodName:  getBroadcastAddress
     * @param ip
     * @param subnetMask  子网掩码
     * @Return java.lang.String
     * @Exception
     * @Description:
     *
     * @author: FLY
     * @date:  2021/1/12 19:02
     */
    public static String getBroadcastAddress(String ip, String subnetMask){
        String ipBinary = toBinary(ip);
        String subnetBinary = toBinary(subnetMask);
        String broadcastBinary = getBroadcastBinary(ipBinary, subnetBinary);
        String wholeBroadcastBinary=spiltBinary(broadcastBinary);
        return binaryToDecimal(wholeBroadcastBinary);
    }
    /**
     * @Title: 二进制的ip字符串转十进制
     * @MethodName:  binaryToDecimal
     * @param wholeBroadcastBinary
     * @Return java.lang.String
     * @Exception
     * @Description:
     *
     * @author: FLY
     * @date:  2021/1/12 19:03
     */
    private static String binaryToDecimal(String wholeBroadcastBinary){
        String[] strings = wholeBroadcastBinary.split("\\.");
        StringBuilder sb = new StringBuilder(40);
        for (int j = 0; j < strings.length ; j++) {
            String s = Integer.valueOf(strings[j], 2).toString();
            sb.append(s).append(".");
        }
        return sb.toString().substring(0,sb.length()-1);
    }
    /**
     * @Title: 按8位分割二进制字符串
     * @MethodName:  spiltBinary
     * @param broadcastBinary
     * @Return java.lang.String
     * @Exception
     * @Description:
     *
     * @author: FLY
     * @date:  2021/1/12 19:03
     */
    private static String spiltBinary(String broadcastBinary){
        StringBuilder stringBuilder = new StringBuilder(40);
        char[] chars = broadcastBinary.toCharArray();
        int count=0;
        for (int j = 0; j < chars.length; j++) {
            if (count==8){
                stringBuilder.append(".");
                count=0;
            }
            stringBuilder.append(chars[j]);
            count++;
        }
        return stringBuilder.toString();
    }
    //得到广播地址的二进制码
    private static String getBroadcastBinary(String ipBinary, String subnetBinary){
        int i = subnetBinary.lastIndexOf('1');
        String broadcastIPBinary = ipBinary.substring(0,i+1);
        for (int j = broadcastIPBinary.length(); j < 32 ; j++) {
            broadcastIPBinary=broadcastIPBinary+"1";
        }
        return broadcastIPBinary;
    }
    //转二进制
    private static String toBinary(String content){
        String binaryString="";
        String[] ipSplit = content.split("\\.");
        for ( String split : ipSplit ) {
            String s = Integer.toBinaryString(Integer.valueOf(split));
            int length = s.length();
            for (int i = length; i <8 ; i++) {
                s="0"+s;
            }
            binaryString = binaryString +s;
        }
        return binaryString;
    }
}