/*
 * 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.impl.object;

import java.util.BitSet;

import org.opendaylight.protocol.pcep.PCEPDeserializerException;
import org.opendaylight.protocol.pcep.PCEPObject;
import org.opendaylight.protocol.pcep.impl.PCEPObjectParser;
import org.opendaylight.protocol.pcep.impl.PCEPTlvParser;
import org.opendaylight.protocol.pcep.object.PCEPLspaObject;
import org.opendaylight.protocol.util.ByteArray;
import com.google.common.primitives.UnsignedInts;

/**
 * Parser for {@link org.opendaylight.protocol.pcep.object.PCEPLspaObject PCEPLspaObject}
 */
public class PCEPLspaObjectParser implements PCEPObjectParser {

	/*
	 * lenghts of fields in bytes
	 */
	public static final int EXC_ANY_F_LENGTH = 4;
	public static final int INC_ANY_F_LENGTH = 4;
	public static final int INC_ALL_F_LENGTH = 4;
	public static final int SET_PRIO_F_LENGTH = 1;
	public static final int HOLD_PRIO_F_LENGTH = 1;
	public static final int FLAGS_F_LENGTH = 1;

	/*
	 * offsets of flags inside flags field in bits
	 */
	public static final int S_FLAG_OFFSET = 6;
	public static final int L_FLAG_OFFSET = 7;

	/*
	 * offsets of fields in bytes
	 */
	public static final int EXC_ANY_F_OFFSET = 0;
	public static final int INC_ANY_F_OFFSET = EXC_ANY_F_OFFSET + EXC_ANY_F_LENGTH;
	public static final int INC_ALL_F_OFFSET = INC_ANY_F_OFFSET + INC_ANY_F_LENGTH;
	public static final int SET_PRIO_F_OFFSET = INC_ALL_F_OFFSET + INC_ALL_F_LENGTH;
	public static final int HOLD_PRIO_F_OFFSET = SET_PRIO_F_OFFSET + SET_PRIO_F_LENGTH;
	public static final int FLAGS_F_OFFSET = HOLD_PRIO_F_OFFSET + HOLD_PRIO_F_LENGTH;
	public static final int TLVS_F_OFFSET = FLAGS_F_OFFSET + FLAGS_F_LENGTH + 1; //added reserved field of length 1B

	@Override
	public PCEPObject parse(byte[] bytes, boolean processed, boolean ignored) throws PCEPDeserializerException {
		if (bytes == null)
			throw new IllegalArgumentException("Bytes array is mandatory.");

		final BitSet flags = ByteArray.bytesToBitSet(ByteArray.subByte(bytes, FLAGS_F_OFFSET, FLAGS_F_LENGTH));

		return new PCEPLspaObject(UnsignedInts.toLong(ByteArray.bytesToInt(ByteArray.subByte(bytes, EXC_ANY_F_OFFSET, EXC_ANY_F_LENGTH))),
				UnsignedInts.toLong(ByteArray.bytesToInt(ByteArray.subByte(bytes, INC_ANY_F_OFFSET, INC_ANY_F_LENGTH))), UnsignedInts.toLong(ByteArray
						.bytesToInt(ByteArray.subByte(bytes, INC_ALL_F_OFFSET, INC_ALL_F_LENGTH))), (short) (bytes[SET_PRIO_F_OFFSET] & 0xFF),
				(short) (bytes[HOLD_PRIO_F_OFFSET] & 0xFF), flags.get(S_FLAG_OFFSET), flags.get(L_FLAG_OFFSET), PCEPTlvParser.parse(ByteArray.cutBytes(bytes, TLVS_F_OFFSET)), processed,
				ignored);
	}

	@Override
	public byte[] put(PCEPObject obj) {
		if (!(obj instanceof PCEPLspaObject))
			throw new IllegalArgumentException("Wrong instance of PCEPObject. Passed " + obj.getClass() + ". Needed PCEPLspaObject.");

		final PCEPLspaObject lspaObj = (PCEPLspaObject) obj;

		final byte[] tlvs = PCEPTlvParser.put(lspaObj.getTlvs());
		final byte[] retBytes = new byte[TLVS_F_OFFSET + tlvs.length];
		ByteArray.copyWhole(tlvs, retBytes, TLVS_F_OFFSET);

		System.arraycopy(ByteArray.longToBytes(lspaObj.getExcludeAny()), 4, retBytes, EXC_ANY_F_OFFSET, EXC_ANY_F_LENGTH);
		System.arraycopy(ByteArray.longToBytes(lspaObj.getIncludeAny()), 4, retBytes, INC_ANY_F_OFFSET, INC_ANY_F_LENGTH);
		System.arraycopy(ByteArray.longToBytes(lspaObj.getIncludeAll()), 4, retBytes, INC_ALL_F_OFFSET, INC_ALL_F_LENGTH);
		retBytes[SET_PRIO_F_OFFSET] = ByteArray.shortToBytes(lspaObj.getSetupPriority())[Short.SIZE / Byte.SIZE - 1];
		retBytes[HOLD_PRIO_F_OFFSET] = ByteArray.shortToBytes(lspaObj.getHoldingPriority())[Short.SIZE / Byte.SIZE - 1];

		final BitSet flags = new BitSet(FLAGS_F_LENGTH * Byte.SIZE);
		flags.set(S_FLAG_OFFSET, lspaObj.isStandByPath());
		flags.set(L_FLAG_OFFSET, lspaObj.isLocalProtected());
		ByteArray.copyWhole(ByteArray.bitSetToBytes(flags, FLAGS_F_LENGTH), retBytes, FLAGS_F_OFFSET);

		return retBytes;
	}

}