/*
 * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
 * and is available at http://www.eclipse.org/legal/epl-v10.html
 */
package org.opendaylight.protocol.bgp.rib.impl;

import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertNotNull;
import static org.junit.Assert.assertTrue;
import static org.mockito.Matchers.any;
import static org.mockito.Mockito.doAnswer;
import static org.mockito.Mockito.doReturn;
import static org.mockito.Mockito.mock;

import com.google.common.collect.Lists;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelHandler;
import io.netty.channel.ChannelPipeline;
import io.netty.channel.EventLoop;
import io.netty.util.concurrent.DefaultPromise;
import io.netty.util.concurrent.GenericFutureListener;
import io.netty.util.concurrent.GlobalEventExecutor;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.net.UnknownHostException;
import java.util.List;
import java.util.concurrent.TimeUnit;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.mockito.Matchers;
import org.mockito.Mock;
import org.mockito.MockitoAnnotations;
import org.mockito.invocation.InvocationOnMock;
import org.mockito.stubbing.Answer;
import org.opendaylight.protocol.bgp.parser.BGPError;
import org.opendaylight.protocol.bgp.parser.BgpExtendedMessageUtil;
import org.opendaylight.protocol.bgp.parser.BgpTableTypeImpl;
import org.opendaylight.protocol.bgp.rib.impl.spi.BGPPeerRegistry;
import org.opendaylight.protocol.bgp.rib.impl.spi.BGPSessionPreferences;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.AsNumber;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.IpAddress;
import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.Ipv4Address;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.LinkstateAddressFamily;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.linkstate.rev150210.LinkstateSubsequentAddressFamily;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Keepalive;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.KeepaliveBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Notify;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.Open;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.OpenBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.ProtocolVersion;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.BgpParameters;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.BgpParametersBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.OptionalCapabilities;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.OptionalCapabilitiesBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.optional.capabilities.CParametersBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.message.rev130919.open.message.bgp.parameters.optional.capabilities.c.parameters.As4BytesCapabilityBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.BgpTableType;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.CParameters1;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.CParameters1Builder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.mp.capabilities.GracefulRestartCapabilityBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.multiprotocol.rev130919.mp.capabilities.MultiprotocolCapabilityBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.Ipv4AddressFamily;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.bgp.types.rev130919.UnicastSubsequentAddressFamily;
import org.opendaylight.yangtools.yang.binding.Notification;

public class FSMTest {


    @Mock
    private EventLoop eventLoop;

    private BGPClientSessionNegotiator clientSession;

    @Mock
    private Channel speakerListener;

    @Mock
    private ChannelPipeline pipeline;

    private final BgpTableType ipv4tt = new BgpTableTypeImpl(Ipv4AddressFamily.class, UnicastSubsequentAddressFamily.class);

    private final BgpTableType linkstatett = new BgpTableTypeImpl(LinkstateAddressFamily.class, LinkstateSubsequentAddressFamily.class);

    private final List<Notification> receivedMsgs = Lists.newArrayList();

    private Open classicOpen;

    @Before
    public void setUp() throws UnknownHostException {
        MockitoAnnotations.initMocks(this);
        final List<BgpParameters> tlvs = Lists.newArrayList();
        final List<OptionalCapabilities> capas = Lists.newArrayList();

        capas.add(new OptionalCapabilitiesBuilder().setCParameters(new CParametersBuilder().addAugmentation(CParameters1.class,
            new CParameters1Builder().setMultiprotocolCapability(new MultiprotocolCapabilityBuilder()
                .setAfi(this.ipv4tt.getAfi()).setSafi(this.ipv4tt.getSafi()).build()).build()).build()).build());
        capas.add(new OptionalCapabilitiesBuilder().setCParameters(new CParametersBuilder().addAugmentation(CParameters1.class,
            new CParameters1Builder().setMultiprotocolCapability(new MultiprotocolCapabilityBuilder()
                .setAfi(this.linkstatett.getAfi()).setSafi(this.linkstatett.getSafi()).build()).build()).build()).build());
        capas.add(new OptionalCapabilitiesBuilder().setCParameters(new CParametersBuilder().setAs4BytesCapability(
                new As4BytesCapabilityBuilder().setAsNumber(new AsNumber(30L)).build()).build()).build());
        capas.add(new OptionalCapabilitiesBuilder().setCParameters(BgpExtendedMessageUtil.EXTENDED_MESSAGE_CAPABILITY).build());
        capas.add(new OptionalCapabilitiesBuilder().setCParameters(new CParametersBuilder().addAugmentation(CParameters1.class,
            new CParameters1Builder().setGracefulRestartCapability(new GracefulRestartCapabilityBuilder().build()).build()).build()).build());


        tlvs.add(new BgpParametersBuilder().setOptionalCapabilities(capas).build());
        final BGPSessionPreferences prefs = new BGPSessionPreferences(new AsNumber(30L), (short) 3, new Ipv4Address("1.1.1.1"), new AsNumber(30L), tlvs);

        final ChannelFuture f = mock(ChannelFuture.class);
        doReturn(null).when(f).addListener(any(GenericFutureListener.class));

        final InetAddress peerAddress = InetAddress.getByName("1.1.1.2");
        doAnswer(new Answer<Object>() {
            @Override
            public Object answer(final InvocationOnMock invocation) {
                final Object[] args = invocation.getArguments();
                FSMTest.this.receivedMsgs.add((Notification) args[0]);
                return f;
            }
        }).when(this.speakerListener).writeAndFlush(any(Notification.class));
        doReturn(this.eventLoop).when(this.speakerListener).eventLoop();
        doReturn(null).when(this.eventLoop).schedule(any(Runnable.class), any(long.class), any(TimeUnit.class));
        doReturn("TestingChannel").when(this.speakerListener).toString();
        doReturn(new InetSocketAddress(peerAddress, 179)).when(this.speakerListener).remoteAddress();
        doReturn(new InetSocketAddress(peerAddress, 179)).when(this.speakerListener).localAddress();
        doReturn(this.pipeline).when(this.speakerListener).pipeline();
        doReturn(this.pipeline).when(this.pipeline).replace(any(ChannelHandler.class), any(String.class), any(ChannelHandler.class));
        doReturn(null).when(this.pipeline).replace(Matchers.<Class<ChannelHandler>>any(), any(String.class), any(ChannelHandler.class));
        doReturn(this.pipeline).when(this.pipeline).addLast(any(ChannelHandler.class));
        doReturn(mock(ChannelFuture.class)).when(this.speakerListener).close();

        final BGPPeerRegistry peerRegistry = new StrictBGPPeerRegistry();
        peerRegistry.addPeer(new IpAddress(new Ipv4Address(peerAddress.getHostAddress())), new SimpleSessionListener(), prefs);

        this.clientSession = new BGPClientSessionNegotiator(new DefaultPromise<BGPSessionImpl>(GlobalEventExecutor.INSTANCE), this.speakerListener, peerRegistry);

        this.classicOpen = new OpenBuilder().setMyAsNumber(30).setHoldTimer(3).setVersion(new ProtocolVersion((short) 4)).setBgpParameters(
            tlvs).setBgpIdentifier(new Ipv4Address("1.1.1.2")).build();
    }

    @Test
    public void testDenyPeer() {
        this.clientSession = new BGPClientSessionNegotiator(new DefaultPromise<BGPSessionImpl>(GlobalEventExecutor.INSTANCE), this.speakerListener, new StrictBGPPeerRegistry());
        this.clientSession.channelActive(null);
        assertEquals(1, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(0) instanceof Notify);
    }

    @Test
    public void testAccSessionChar() throws InterruptedException {
        this.clientSession.channelActive(null);
        assertEquals(1, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(0) instanceof Open);
        this.clientSession.handleMessage(this.classicOpen);
        assertEquals(2, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(1) instanceof Keepalive);
        this.clientSession.handleMessage(new KeepaliveBuilder().build());
        assertEquals(this.clientSession.getState(), BGPClientSessionNegotiator.State.FINISHED);
        Thread.sleep(1000);
        Thread.sleep(100);
    }

    @Test
    public void testNotAccChars() throws InterruptedException {
        this.clientSession.channelActive(null);
        assertEquals(1, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(0) instanceof Open);
        this.clientSession.handleMessage(new OpenBuilder().setMyAsNumber(30).setHoldTimer(1).setBgpIdentifier(new Ipv4Address("127.0.0.1")).setVersion(new ProtocolVersion((short) 4)).build());
        assertEquals(2, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(1) instanceof Notify);
        final Notification m = this.receivedMsgs.get(this.receivedMsgs.size() - 1);
        assertEquals(BGPError.UNSPECIFIC_OPEN_ERROR, BGPError.forValue(((Notify) m).getErrorCode(), ((Notify) m).getErrorSubcode()));
    }

    @Test
    public void testNoAs4BytesCapability() {
        this.clientSession.channelActive(null);
        assertEquals(1, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(0) instanceof Open);

        final List<BgpParameters> tlvs = Lists.newArrayList();
        final List<OptionalCapabilities> capas = Lists.newArrayList();
        capas.add(new OptionalCapabilitiesBuilder().setCParameters(new CParametersBuilder().addAugmentation(CParameters1.class,
            new CParameters1Builder().setMultiprotocolCapability(new MultiprotocolCapabilityBuilder()
                .setAfi(this.ipv4tt.getAfi()).setSafi(this.ipv4tt.getSafi()).build()).build()).build()).build());
        capas.add(new OptionalCapabilitiesBuilder().setCParameters(BgpExtendedMessageUtil.EXTENDED_MESSAGE_CAPABILITY).build());
        tlvs.add(new BgpParametersBuilder().setOptionalCapabilities(capas).build());
        // Open Message without advertised four-octet AS Number capability
        this.clientSession.handleMessage(new OpenBuilder().setMyAsNumber(30).setHoldTimer(1).setVersion(
            new ProtocolVersion((short) 4)).setBgpParameters(tlvs).setBgpIdentifier(new Ipv4Address("1.1.1.2")).build());
        assertEquals(2, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(1) instanceof Notify);
        final Notification m = this.receivedMsgs.get(this.receivedMsgs.size() - 1);
        assertEquals(BGPError.UNSUPPORTED_CAPABILITY, BGPError.forValue(((Notify) m).getErrorCode(), ((Notify) m).getErrorSubcode()));
        assertNotNull(((Notify) m).getData());
    }

    @Test
    public void testBgpExtendedMessageCapability() {
        this.clientSession.channelActive(null);
        assertEquals(1, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(0) instanceof Open);

        final List<BgpParameters> tlvs = Lists.newArrayList();
        final List<OptionalCapabilities> capas = Lists.newArrayList();
        capas.add(new OptionalCapabilitiesBuilder().setCParameters(new CParametersBuilder().addAugmentation(CParameters1.class,
                new CParameters1Builder().setMultiprotocolCapability(new MultiprotocolCapabilityBuilder()
                        .setAfi(this.ipv4tt.getAfi()).setSafi(this.ipv4tt.getSafi()).build()).build()).build()).build());
        capas.add(new OptionalCapabilitiesBuilder().setCParameters(new CParametersBuilder().setAs4BytesCapability(
                new As4BytesCapabilityBuilder().setAsNumber(new AsNumber(30L)).build()).build()).build());
        tlvs.add(new BgpParametersBuilder().setOptionalCapabilities(capas).build());
        this.clientSession.handleMessage(new OpenBuilder().setMyAsNumber(30).setHoldTimer(1).setVersion(
                new ProtocolVersion((short) 4)).setBgpParameters(tlvs).setBgpIdentifier(new Ipv4Address("1.1.1.2")).build());
        assertEquals(2, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(1) instanceof Keepalive);

    }

    @Test
    public void sendNotification() {
        this.clientSession.channelActive(null);
        this.clientSession.handleMessage(this.classicOpen);
        this.clientSession.handleMessage(new KeepaliveBuilder().build());
        assertEquals(this.clientSession.getState(), BGPClientSessionNegotiator.State.FINISHED);
        this.clientSession.handleMessage(new OpenBuilder().setMyAsNumber(30).setHoldTimer(3).setVersion(new ProtocolVersion((short) 4)).build());
        assertEquals(3, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(2) instanceof Notify);
        final Notification m = this.receivedMsgs.get(2);
        assertEquals(BGPError.FSM_ERROR.getCode(), ((Notify) m).getErrorCode().shortValue());
        assertEquals(BGPError.FSM_ERROR.getSubcode(), ((Notify) m).getErrorSubcode().shortValue());
    }

    @Test
    public void sameBGPIDs() {
        this.clientSession.channelActive(null);
        assertEquals(1, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(0) instanceof Open);

        this.clientSession.handleMessage(new OpenBuilder(this.classicOpen).setBgpIdentifier(new Ipv4Address("1.1.1.1")).build());
        assertEquals(2, this.receivedMsgs.size());
        assertTrue(this.receivedMsgs.get(1) instanceof Notify);
        final Notification m = this.receivedMsgs.get(this.receivedMsgs.size() - 1);
        assertEquals(BGPError.BAD_BGP_ID, BGPError.forValue(((Notify) m).getErrorCode(), ((Notify) m).getErrorSubcode()));
    }

    @After
    public void tearDown() {

    }
}