// package jp.co.ascade.net;

import java.util.Arrays;
import java.util.ArrayList;
import java.io.IOException;
import java.net.InetAddress;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.UnknownHostException;

/**
 * Library for Wake-on-Lan.
 *
 * <pre>
 * Use of WakeOnLan lib.
 *     try{
 *         // Set broadcast address and port number.(ex. 192.168.1.255:2304)
 *         WakeOnLan wol = new WakeOnLan("192.168.1.255", 2304);
 *         // Use default configuration. (255.255.255.255:9)
 *         // WakeOnLan wol = new WakeOnLan();
 *
 *         // Send MagicPacket to specified IEEE address(ex. 00:01:02:03:04:05)
 *        wol.send("00:01:02:03:04:05");
 *     }
 *     catch(java.io.IOException){
 *         // error handling
 *     }
 * </pre>
 */
public class WakeOnLan
{
    final static public String DEFAULT_ADDRESS = "255.255.255.255";
    final static public int DEFAULT_PORT = 9;// AMD's Magic Packet Utility 2304
    final static public String MAC_SEPARATOR = "(\\:|\\-|\\.|\\ )";

    /////////////////////////////////////////////////////////////////////////

    private InetAddress ipAddress;
    private int port;
    
    public WakeOnLan()
    {
        try{
            init(InetAddress.getByName(DEFAULT_ADDRESS), DEFAULT_PORT);
        }catch(UnknownHostException e){} // ignore UnknownHostException.
    }
    public WakeOnLan(String ipAddress)
        throws UnknownHostException
    {
        init(InetAddress.getByName(ipAddress), port);
    }
    public WakeOnLan(String ipAddress, int port)
        throws UnknownHostException
    {
        init(InetAddress.getByName(ipAddress), port);
    }
    public WakeOnLan(InetAddress ipAddress){
        init(ipAddress, DEFAULT_PORT);
    }
    public WakeOnLan(InetAddress ipAddress, int port){
        init(ipAddress, port);
    }
    private void init(InetAddress ipAddress, int port){
        this.ipAddress = ipAddress;
        this.port = port;
    }
    
    public void send(String macAddress)
        throws IOException,
               InvalidMacAddressException
    {
        send(parseMac(macAddress, MAC_SEPARATOR));
    }

    public void send(byte[] macAddress)
        throws IOException,
               InvalidMacAddressException
    {
        byte[] packet = makePacket(macAddress);

        DatagramPacket dpacket =
        new DatagramPacket(packet, packet.length, this.ipAddress, this.port);

        DatagramSocket socket = new DatagramSocket();
        try{
            socket.send(dpacket);
        }
        finally{
            socket.close();
        }
    }

    private byte[] makePacket(byte[] macAddress)
        throws InvalidMacAddressException
    {
        int addrSize = macAddress.length;
        if(6 != addrSize){
            throw new InvalidMacAddressException("Invalid mac address length("
                                                 + addrSize + ")");
        }

        byte[] packet = new byte[6 + (addrSize * 16)];
        // a synchronization stream of 6 bytes of FFh.
        Arrays.fill(packet, 0, 6, (byte)0xff);
        // 16 times the repetition of the Ethernet address
        for(int i = 0; i < 16; i += 1){
            int start = 6 + (addrSize * i);
            System.arraycopy(macAddress, 0, packet, start, addrSize);
        }
        return packet;
    }
    
    private byte[] parseMac(String addr, String separator)
        throws InvalidMacAddressException
    {
        try{
            String[] sbytes = addr.split(separator);
            byte[] bytes = new byte[sbytes.length];
            for(int i = 0; i < bytes.length; i += 1){
                bytes[i] = (byte)Integer.parseInt(sbytes[i], 16);
            }
            return bytes;
        }
        catch(NumberFormatException nfe){
            throw new InvalidMacAddressException("Invalid mac address - "
                                                 + addr);
        }
    }

    /////////////////////////////////////////////////////////////////////////

    public class InvalidMacAddressException
        extends IOException
    {
        public InvalidMacAddressException(String msg){
            super(msg);
        }
    }

    /////////////////////////////////////////////////////////////////////////

    static private void usage(){
        System.out.println("Usage: WakeOnLan [-h] [-v] [-p port]"
                           + " [-i broadcast-ip-address] mac-address ...");
        System.out.println("Ex.) WakeOnLan -i 192.168.1.255"
                           + " 00:01:02:03:04:05 00:0a:0b:0c:0d:0e");
        System.exit(-1);
    }

    static public void main(String[] args)
        throws Exception
    {
        boolean isVerbose = false;
        String ipAddress = DEFAULT_ADDRESS;
        int port = DEFAULT_PORT;
        ArrayList<String> macAddressList = new ArrayList<String>();

        //////////////////////////////////////////////////////

        try{
            for(int i = 0; i < args.length; i += 1){
                String arg = args[i];
                if("-h".equals(arg)){
                    usage();
                }
                else if("-v".equals(arg)){
                    isVerbose = true;
                }
                else if("-p".equals(arg)){
                    i += 1; port = Integer.parseInt(args[i]);
                }
                else if("-i".equals(arg)){
                    i += 1; ipAddress = args[i];
                }
                else{
                    macAddressList.add(arg);
                }
            }
        }
        catch(Exception e){
            usage();
        }
        if(0 == macAddressList.size())
        {
            usage();
        }

        //////////////////////////////////////////////////////

        WakeOnLan wol = new WakeOnLan(ipAddress, port);
        for(int i = 0; i < macAddressList.size(); i += 1){
            String macAddress = macAddressList.get(i);
            wol.send(macAddress);
            if(isVerbose){
                System.out.println("Sent Wake-on-LAN packet("
                                   + macAddress + ") to "
                                   + ipAddress + "(" + port + ").");
            }
        }
    }
}