/*
 * Copyright 2016-present Open Networking Laboratory
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.onosproject.ospf.protocol.lsa.types;

import com.google.common.base.MoreObjects;
import com.google.common.primitives.Bytes;
import org.jboss.netty.buffer.ChannelBuffer;
import org.onosproject.ospf.controller.OspfLsaType;
import org.onosproject.ospf.protocol.lsa.OpaqueLsaHeader;

import java.util.Arrays;

/**
 * Representation of an Opaque LSA of type link local (9).
 */
public class OpaqueLsa9 extends OpaqueLsaHeader {

    /*
       0                   1                   2                   3
       0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |            LS age             |     Options   |   9, 10 or 11 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |  Opaque Type  |               Opaque ID                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      Advertising Router                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                      LS Sequence Number                       |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         LS checksum           |           Length              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                                                               |
      +                                                               +
      |                      Opaque Information                       |
      +                                                               +
      |                              ...                              |
     */
    private byte[] opaqueInfo = null;

    /**
     * Creates an instance of Opaque type 9 LSA.
     *
     * @param lsaHeader LSA header instance
     */
    public OpaqueLsa9(OpaqueLsaHeader lsaHeader) {
        populateHeader(lsaHeader);
    }

    /**
     * Reads from channel buffer and populate instance.
     *
     * @param channelBuffer channelBuffer instance
     */
    public void readFrom(ChannelBuffer channelBuffer) {
        int length = channelBuffer.readableBytes();
        opaqueInfo = new byte[length];
        channelBuffer.readBytes(opaqueInfo, 0, length);
    }

    /**
     * Returns instance as bytes.
     *
     * @return instance as bytes
     */
    public byte[] asBytes() {
        byte[] lsaMessage = null;

        byte[] lsaHeader = getOpaqueLsaHeaderAsByteArray();
        byte[] lsaBody = getLsaBodyAsByteArray();
        lsaMessage = Bytes.concat(lsaHeader, lsaBody);

        return lsaMessage;
    }

    /**
     * Gets the LSA body.
     *
     * @return the LSA body
     */
    public byte[] getLsaBodyAsByteArray() {
        return opaqueInfo;

    }

    @Override
    public OspfLsaType getOspfLsaType() {
        return OspfLsaType.LINK_LOCAL_OPAQUE_LSA;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        OpaqueLsa9 that = (OpaqueLsa9) o;
        return Arrays.equals(opaqueInfo, that.opaqueInfo);
    }

    @Override
    public int hashCode() {
        return Arrays.hashCode(opaqueInfo);
    }

    @Override
    public String toString() {
        return MoreObjects.toStringHelper(getClass())
                .omitNullValues()
                .add("opaqueInfo", opaqueInfo)
                .toString();
    }
}