/*
 * 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.pcep.parser.object;

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

import io.netty.buffer.ByteBuf;
import io.netty.buffer.Unpooled;
import java.util.List;
import org.opendaylight.protocol.pcep.PCEPDeserializerException;
import org.opendaylight.protocol.pcep.spi.AbstractObjectWithTlvsParser;
import org.opendaylight.protocol.pcep.spi.ObjectUtil;
import org.opendaylight.protocol.pcep.spi.TlvRegistry;
import org.opendaylight.protocol.pcep.spi.VendorInformationTlvRegistry;
import org.opendaylight.protocol.util.BitArray;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.Object;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.ObjectHeader;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.RequestId;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.Tlv;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.order.tlv.Order;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.path.setup.type.tlv.PathSetupType;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.rp.object.Rp;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.rp.object.RpBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.rp.object.rp.Tlvs;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.rp.object.rp.TlvsBuilder;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.pcep.types.rev181109.vendor.information.tlvs.VendorInformationTlv;
import org.opendaylight.yangtools.yang.common.Uint32;
import org.opendaylight.yangtools.yang.common.Uint8;
import org.opendaylight.yangtools.yang.common.netty.ByteBufUtils;

/**
 * Parser for {@link Rp}.
 */
public class PCEPRequestParameterObjectParser extends AbstractObjectWithTlvsParser<TlvsBuilder> {
    private static final int CLASS = 2;
    private static final int TYPE = 1;

    /*
     * lengths of fields in bytes
     */
    private static final int FLAGS_SIZE = 32;

    /*
     * lengths of subfields inside multi-field in bits
     */
    private static final int FLAGS_SF_LENGTH = 29;

    /*
     * offsets of subfields inside multi-field in bits
     */
    private static final int FLAGS_SF_OFFSET = 0;
    private static final int PRI_SF_OFFSET = FLAGS_SF_OFFSET + FLAGS_SF_LENGTH;

    /*
     * flags offsets inside flags sub-field in bits
     */
    private static final int O_FLAG_OFFSET = 26;
    private static final int B_FLAG_OFFSET = 27;
    private static final int R_FLAG_OFFSET = 28;

    /*
     * GCO extension flags offsets inside flags sub-field in bits
     */
    private static final int M_FLAG_OFFSET = 21;
    private static final int D_FLAG_OFFSET = 22;

    /*
     * Path-key bit (RFC5520)
     */
    private static final int P_FLAG_OFFSET = 23;
    /*
     * OF extension flags offsets inside flags sub.field in bits
     */
    private static final int S_FLAG_OFFSET = 24;
    /*
     * RFC6006 flags
     */
    private static final int F_FLAG_OFFSET = 18;
    private static final int N_FLAG_OFFSET = 19;
    private static final int E_FLAG_OFFSET = 20;

    public PCEPRequestParameterObjectParser(final TlvRegistry tlvReg, final VendorInformationTlvRegistry viTlvReg) {
        super(tlvReg, viTlvReg, CLASS, TYPE);
    }

    @Override
    public Object parseObject(final ObjectHeader header, final ByteBuf bytes) throws PCEPDeserializerException {
        checkArgument(bytes != null && bytes.isReadable(), "Array of bytes is mandatory. Cannot be null or empty.");
        final BitArray flags = BitArray.valueOf(bytes, FLAGS_SIZE);
        final Uint32 reqId = ByteBufUtils.readUint32(bytes);
        final TlvsBuilder tlvsBuilder = new TlvsBuilder();
        parseTlvs(tlvsBuilder, bytes.slice());
        final RpBuilder builder = new RpBuilder()
                .setIgnore(header.getIgnore())
                .setProcessingRule(header.getProcessingRule())
                .setFragmentation(flags.get(F_FLAG_OFFSET))
                .setP2mp(flags.get(N_FLAG_OFFSET))
                .setEroCompression(flags.get(E_FLAG_OFFSET))
                .setMakeBeforeBreak(flags.get(M_FLAG_OFFSET))
                .setOrder(flags.get(D_FLAG_OFFSET))
                .setPathKey(flags.get(P_FLAG_OFFSET))
                .setSupplyOf(flags.get(S_FLAG_OFFSET))
                .setLoose(flags.get(O_FLAG_OFFSET))
                .setBiDirectional(flags.get(B_FLAG_OFFSET))
                .setReoptimization(flags.get(R_FLAG_OFFSET))
                .setRequestId(new RequestId(reqId))
                .setTlvs(tlvsBuilder.build());

        short priority = 0;
        priority |= flags.get(PRI_SF_OFFSET + 2) ? 1 : 0;
        priority |= (flags.get(PRI_SF_OFFSET + 1) ? 1 : 0) << 1;
        priority |= (flags.get(PRI_SF_OFFSET) ? 1 : 0) << 2;
        if (priority != 0) {
            builder.setPriority(Uint8.valueOf(priority));
        }

        return builder.build();
    }

    @Override
    public void addTlv(final TlvsBuilder builder, final Tlv tlv) {
        if (tlv instanceof Order) {
            builder.setOrder((Order) tlv);
        }
        if (tlv instanceof PathSetupType) {
            builder.setPathSetupType((PathSetupType) tlv);
        }
    }

    @Override
    public void serializeObject(final Object object, final ByteBuf buffer) {
        checkArgument(object instanceof Rp, "Wrong instance of PCEPObject. Passed %s. Needed RPObject.",
            object.getClass());
        final ByteBuf body = Unpooled.buffer();
        final Rp rpObj = (Rp) object;
        final BitArray flags = new BitArray(FLAGS_SIZE);
        flags.set(R_FLAG_OFFSET, rpObj.getReoptimization());
        flags.set(B_FLAG_OFFSET, rpObj.getBiDirectional());
        flags.set(O_FLAG_OFFSET, rpObj.getLoose());
        flags.set(M_FLAG_OFFSET, rpObj.getMakeBeforeBreak());
        flags.set(D_FLAG_OFFSET, rpObj.getOrder());
        flags.set(P_FLAG_OFFSET, rpObj.getPathKey());
        flags.set(S_FLAG_OFFSET, rpObj.getSupplyOf());
        flags.set(F_FLAG_OFFSET, rpObj.getFragmentation());
        flags.set(N_FLAG_OFFSET, rpObj.getP2mp());
        flags.set(E_FLAG_OFFSET, rpObj.getEroCompression());
        final byte[] res = flags.array();
        if (rpObj.getPriority() != null) {
            final byte p = rpObj.getPriority().byteValue();
            res[res.length - 1] = (byte) (res[res.length - 1] | p);
        }
        body.writeBytes(res);
        final RequestId requestId = rpObj.getRequestId();
        checkArgument(requestId != null, "RequestId is mandatory");
        ByteBufUtils.write(body, requestId.getValue());
        serializeTlvs(rpObj.getTlvs(), body);
        ObjectUtil.formatSubobject(TYPE, CLASS, object.getProcessingRule(), object.getIgnore(), body, buffer);
    }

    public void serializeTlvs(final Tlvs tlvs, final ByteBuf body) {
        if (tlvs != null) {
            if (tlvs.getOrder() != null) {
                serializeTlv(tlvs.getOrder(), body);
            }
            if (tlvs.getPathSetupType() != null) {
                serializeTlv(tlvs.getPathSetupType(), body);
            }
            serializeVendorInformationTlvs(tlvs.getVendorInformationTlv(), body);
        }
    }

    @Override
    protected final void addVendorInformationTlvs(final TlvsBuilder builder, final List<VendorInformationTlv> tlvs) {
        if (!tlvs.isEmpty()) {
            builder.setVendorInformationTlv(tlvs);
        }
    }
}