/*
 * Copyright (c) 2015 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.rsvp.parser.impl.subobject.rro;

import static com.google.common.base.Preconditions.checkArgument;

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import org.opendaylight.protocol.rsvp.parser.spi.RROSubobjectParser;
import org.opendaylight.protocol.rsvp.parser.spi.RROSubobjectSerializer;
import org.opendaylight.protocol.rsvp.parser.spi.RSVPParsingException;
import org.opendaylight.protocol.util.BitArray;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.rsvp.rev150820.UnnumberedSubobject;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.rsvp.rev150820._record.route.subobjects.SubobjectType;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.rsvp.rev150820._record.route.subobjects.list.SubobjectContainer;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.rsvp.rev150820._record.route.subobjects.list.SubobjectContainerBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.rsvp.rev150820._record.route.subobjects.subobject.type.UnnumberedCase;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.rsvp.rev150820._record.route.subobjects.subobject.type.UnnumberedCaseBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.rsvp.rev150820._record.route.subobjects.subobject.type.unnumbered._case.UnnumberedBuilder;
import org.opendaylight.yangtools.yang.common.netty.ByteBufUtils;

/**
 * Parser for {@link UnnumberedCase}.
 */
public class RROUnnumberedInterfaceSubobjectParser implements RROSubobjectParser, RROSubobjectSerializer {
    public static final int TYPE = 4;

    private static final int FLAGS_SIZE = 8;
    private static final int RESERVED = 1;
    private static final int CONTENT_LENGTH = 10;
    private static final int LPA_F_OFFSET = 7;
    private static final int LPIU_F_OFFSET = 6;

    @Override
    public SubobjectContainer parseSubobject(final ByteBuf buffer) throws RSVPParsingException {
        checkArgument(buffer != null && buffer.isReadable(), "Array of bytes is mandatory. Cannot be null or empty.");
        if (buffer.readableBytes() != CONTENT_LENGTH) {
            throw new RSVPParsingException("Wrong length of array of bytes. Passed: " + buffer.readableBytes() + "; "
                + "Expected: " + CONTENT_LENGTH + ".");
        }
        final BitArray flags = BitArray.valueOf(buffer, FLAGS_SIZE);
        buffer.skipBytes(RESERVED);
        return new SubobjectContainerBuilder()
                .setProtectionAvailable(flags.get(LPA_F_OFFSET))
                .setProtectionInUse(flags.get(LPIU_F_OFFSET))
                .setSubobjectType(new UnnumberedCaseBuilder()
                    .setUnnumbered(new UnnumberedBuilder()
                        .setRouterId(ByteBufUtils.readUint32(buffer))
                        .setInterfaceId(ByteBufUtils.readUint32(buffer))
                        .build())
                    .build())
                .build();
    }

    @Override
    public void serializeSubobject(final SubobjectContainer subobject, final ByteBuf buffer) {
        final SubobjectType type = subobject.getSubobjectType();
        checkArgument(type instanceof UnnumberedCase, "Unknown subobject instance. Passed %s. Needed UnnumberedCase.",
            type.getClass());
        final BitArray flags = new BitArray(FLAGS_SIZE);
        flags.set(LPA_F_OFFSET, subobject.getProtectionAvailable());
        flags.set(LPIU_F_OFFSET, subobject.getProtectionInUse());
        final ByteBuf body = Unpooled.buffer(CONTENT_LENGTH);
        flags.toByteBuf(body);
        body.writeZero(RESERVED);

        final UnnumberedSubobject specObj = ((UnnumberedCase) type).getUnnumbered();
        ByteBufUtils.writeMandatory(body, specObj.getRouterId(), "RouterId");
        ByteBufUtils.writeMandatory(body, specObj.getInterfaceId(), "InterfaceId");
        RROSubobjectUtil.formatSubobject(TYPE, body, buffer);
    }
}