/*

 * Copyright (c) 2013, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

import java.net.InetAddress;

import java.net.NetworkInterface;

import java.net.SocketException;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Enumeration;

import java.util.List;

/*

 * @test

 * @bug 8021372

 * @summary Tests that the MAC addresses returned by NetworkInterface.getNetworkInterfaces are unique for each adapter.

 *

 */

public class UniqueMacAddressesTest {

    public static void main(String[] args) throws Exception {

        new UniqueMacAddressesTest().execute();

        System.out.println("UniqueMacAddressesTest: OK");

    }

    public UniqueMacAddressesTest() {

        System.out.println("UniqueMacAddressesTest: start ");

    }

    public void execute() throws Exception {

        Enumeration<NetworkInterface> networkInterfaces;

        boolean areMacAddressesUnique = false;

        List<NetworkInterface> networkInterfaceList = new ArrayList<NetworkInterface>();

            networkInterfaces = NetworkInterface.getNetworkInterfaces();

        // build a list of NetworkInterface objects to test MAC address

        // uniqueness

        createNetworkInterfaceList(networkInterfaces, networkInterfaceList);

        areMacAddressesUnique = checkMacAddressesAreUnique(networkInterfaceList);

        if (!areMacAddressesUnique) {

            throw new RuntimeException("mac address uniqueness test failed");

        }

    }

    private boolean checkMacAddressesAreUnique (

            List<NetworkInterface> networkInterfaces) throws Exception {

        boolean uniqueMacAddresses = true;

        for (NetworkInterface networkInterface : networkInterfaces) {

            for (NetworkInterface comparisonNetIf : networkInterfaces) {

                System.out.println("Comparing netif "

                        + networkInterface.getName() + " and netif "

                        + comparisonNetIf.getName());

                if (testMacAddressesEqual(networkInterface, comparisonNetIf)) {

                    uniqueMacAddresses = false;

                    break;

                }

            }

            if (uniqueMacAddresses != true)

                break;

        }

        return uniqueMacAddresses;

    }

    private boolean testMacAddressesEqual(NetworkInterface netIf1,

            NetworkInterface netIf2) throws Exception {

        byte[] rawMacAddress1 = null;

        byte[] rawMacAddress2 = null;

        boolean macAddressesEqual = false;

        if (!netIf1.getName().equals(netIf2.getName())) {

            System.out.println("compare hardware addresses "

                +  createMacAddressString(netIf1) + " and " + createMacAddressString(netIf2));

            rawMacAddress1 = netIf1.getHardwareAddress();

            rawMacAddress2 = netIf2.getHardwareAddress();

            macAddressesEqual = Arrays.equals(rawMacAddress1, rawMacAddress2);

        } else {

            // same interface

            macAddressesEqual = false;

        }

        return macAddressesEqual;

    }

    private String createMacAddressString (NetworkInterface netIf) throws Exception {

        byte[] macAddr = netIf.getHardwareAddress();

        StringBuilder sb =  new StringBuilder();

        if (macAddr != null) {

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

                sb.append(String.format("%02X%s", macAddr[i],

                        (i < macAddr.length - 1) ? "-" : ""));

            }

        }

        return sb.toString();

    }

    private void createNetworkInterfaceList(Enumeration<NetworkInterface> nis,

            List<NetworkInterface> networkInterfaceList) throws Exception {

        byte[] macAddr = null;

        NetworkInterface netIf = null;

        while (nis.hasMoreElements()) {

            netIf = (NetworkInterface) nis.nextElement();

            macAddr = netIf.getHardwareAddress();

            if (macAddr != null) {

                System.out

                        .println("Adding NetworkInterface " + netIf.getName());

                networkInterfaceList.add(netIf);

            }

        }

    }

}