/*

 * Copyright 2009 Sun Microsystems, Inc.  All Rights Reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

import java.net.NetworkInterface;

import java.net.InetSocketAddress;

import java.net.SocketAddress;

import java.net.InetAddress;

import java.net.Inet4Address;

import java.net.SocketException;

import java.io.IOException;

import java.io.PrintStream;

import java.io.UnsupportedEncodingException;

import java.util.List;

import java.util.ArrayList;

import java.util.Set;

import java.util.Collections;

import java.util.Enumeration;

import java.util.Iterator;

import java.nio.ByteBuffer;

import com.sun.nio.sctp.SctpChannel;

import static java.lang.System.out;

public class Util {

    static final int SMALL_BUFFER = 128;

    static final String SMALL_MESSAGE =

      "Under the bridge and over the dam, looking for berries, berries for jam";

    static final int LARGE_BUFFER = 32768;

    static final String LARGE_MESSAGE;

    static {

        StringBuffer sb = new StringBuffer(LARGE_BUFFER);

        for (int i=0; i<460; i++)

          sb.append(SMALL_MESSAGE);

        LARGE_MESSAGE = sb.toString();

    }

    static boolean isSCTPSupported() {

        try {

            SctpChannel c = SctpChannel.open();

            c.close();

            return true;

        } catch (IOException ioe) {

            ioe.printStackTrace();

        } catch (UnsupportedOperationException e) {

            out.println(e);

        }

        return false;

    }

    /**

     * Returns a list of all the addresses on the system.

     * @param  inclLoopback

     *         if {@code true}, include the loopback addresses

     * @param  ipv4Only

     *         it {@code true}, only IPv4 addresses will be included

     */

    static List<InetAddress> getAddresses(boolean inclLoopback,

                                          boolean ipv4Only)

        throws SocketException {

        ArrayList<InetAddress> list = new ArrayList<InetAddress>();

        Enumeration<NetworkInterface> nets =

                 NetworkInterface.getNetworkInterfaces();

        for (NetworkInterface netInf : Collections.list(nets)) {

            Enumeration<InetAddress> addrs = netInf.getInetAddresses();

            for (InetAddress addr : Collections.list(addrs)) {

                if (!list.contains(addr) &&

                        (inclLoopback ? true : !addr.isLoopbackAddress()) &&

                        (ipv4Only ? (addr instanceof Inet4Address) : true)) {

                    list.add(addr);

                }

            }

        }

        return list;

    }

    static void dumpAddresses(SctpChannel channel,

                              PrintStream printStream)

        throws IOException {

        Set<SocketAddress> addrs = channel.getAllLocalAddresses();

        printStream.println("Local Addresses: ");

        for (Iterator<SocketAddress> it = addrs.iterator(); it.hasNext(); ) {

            InetSocketAddress addr = (InetSocketAddress)it.next();

            printStream.println("\t" + addr);

        }

    }

    /**

     * Compare the contents of the given ByteBuffer with the contens of the

     * given byte array. true if, and only if, the contents are the same.

     */

    static boolean compare(ByteBuffer bb, byte[] message) {

        if (message.length != bb.remaining()) {

            out.println("Compare failed, byte array length != to buffer remaining");

            return false;

        }

        for (int i=0; i<message.length; i++) {

            byte b = bb.get();

            if (message[i] != b) {

                out.println("Position " + i + ": " + message[i] + " != " + b);

                return false;

            }

        }

        return true;

    }

    static boolean compare(ByteBuffer bb, String str) {

        try{

            return Util.compare(bb, str.getBytes("ISO-8859-1"));

        } catch (UnsupportedEncodingException unsupported) {

            throw new AssertionError(unsupported);

        }

    }

}