package org.jscsi.target.scsi.modeSense;

import java.nio.ByteBuffer;

import org.jscsi.target.util.BitManip;
import org.jscsi.target.util.ReadWrite;

/**
 * A {@link ModeParameterHeader} sub-class. Instances of this class are sent in
 * response to <code>MODE SENSE (10)</code> SCSI commands and have a serialized
 * length of 8 bytes.
 * 
 * @see LongLogicalBlockDescriptor
 * @author Andreas Ergenzinger
 */
public final class ModeParameterHeader10 extends ModeParameterHeader {

    /**
     * The length of this object when serialized.
     */
    static final int SIZE = 8;

    /**
     * The length in bytes of the MODE DATA LENGTH field.
     */
    static final int MODE_DATA_LENGTH_FIELD_SIZE = 2;

    /**
     * If the Long LBA (LONGLBA) bit is set to zero, the MODE PARAMETER BLOCK
     * DESCRIPTOR(s), if any, are each eight bytes long and have the format
     * described in SPC-3. If the LONGLBA bit is set to one, the mode parameter
     * block descriptor(s), if any, are each sixteen bytes long and have a
     * format described in a non-general command standard.
     */
    private final boolean longLba;

    /**
     * The constructor.
     * 
     * @param modeDataLength
     *            the total length in bytes of all MODE DATA list elements
     * @param blockDescriptorLength
     *            the total length in bytes of all BLOCK DESCRIPTOR list
     *            elements
     * @param longLba
     *            if <code>true</code> then the LONG LBA MODE PAREMETER LOGICAL
     *            BLOCK DESCRIPTOR format will be used
     * @see LongLogicalBlockDescriptor
     * @see ShortLogicalBlockDescriptor
     */
    public ModeParameterHeader10(final int modeDataLength, final int blockDescriptorLength, final boolean writeProtect,
        final boolean longLba) {
        super(modeDataLength, blockDescriptorLength, writeProtect);
        this.longLba = longLba;
    }

    public void serialize(final ByteBuffer byteBuffer, final int index) {
        ReadWrite.writeTwoByteInt(byteBuffer,// buffer
            modeDataLength,// value
            index);// index
        byteBuffer.position(index + 2);
        byteBuffer.put(mediumType);
        byteBuffer.put(deviceSpecificParameter);
        final byte zeroByte = 0;
        byteBuffer.put(BitManip.getByteWithBitSet(zeroByte, 0, longLba));
        byteBuffer.put(zeroByte);
        ReadWrite.writeTwoByteInt(byteBuffer,// buffer
            blockDescriptorLength,// value
            index + 6);// index
    }

    public int size() {
        return SIZE;
    }

}