package org.jscsi.target.scsi.cdb;

 import java.nio.ByteBuffer;

 import org.jscsi.target.scsi.modeSense.ModePageCode;

 import org.jscsi.target.scsi.modeSense.PageControl;

 import org.jscsi.target.util.BitManip;

 import org.jscsi.target.util.ReadWrite;

 /**

  * This class represents Command Descriptor Blocks for the <code>MODE SENSE (6)</code> SCSI command.

  * 

  * @author Andreas Ergenzinger

  */

 public final class ModeSense6Cdb extends CommandDescriptorBlock {

     /**

      * A disable block descriptors (DBD) bit set to zero specifies that the device server may return zero or more block

      * descriptors in the returned MODE SENSE data (see 7.4). A DBD bit set to one specifies that the device server

      * shall not return any block descriptors in the returned MODE SENSE data.

      */

     private final boolean disableBlockDescriptors;

     /**

      * The page control (PC) field specifies the type of mode parameter values to be returned in the mode pages.

      */

     private final PageControl pageControl;

     /**

      * The PAGE CODE and SUBPAGE CODE fields specify which mode pages and subpages to return.

      * 

      * @see #subpageCode

      */

     private final int pageCode;

     /**

      * The PAGE CODE and SUBPAGE CODE fields specify which mode pages and subpages to return

      * 

      * @see #pageCode

      */

     private final int subpageCode;

     /**

      * The ALLOCATION LENGTH field specifies the maximum number of bytes that an application client has allocated in the

      * Data-In Buffer. An allocation length of zero specifies that no data shall be transferred.

      */

     private final int allocationLength;

     public ModeSense6Cdb (ByteBuffer buffer) {

         super(buffer);// SCSI Operation Code + Control

         // DBD

         disableBlockDescriptors = BitManip.getBit(buffer.get(1),// byte

                 3);// bit number

         // PC

         int i = (buffer.get(2) >> 6) & 3;

         pageControl = PageControl.getPageControl(i);

         // PAGE CODE

         pageCode = buffer.get(2) & 63;

         // SUBPAGE CODE

         subpageCode = ReadWrite.readOneByteInt(buffer, 3);

         // ALLOCATION LENGTH

         allocationLength = ReadWrite.readOneByteInt(buffer, 4);

     }

     public boolean getDisableBlockDescriptors () {

         return disableBlockDescriptors;

     }

     public PageControl getPageControl () {

         return pageControl;

     }

     public int getPageCode () {

         return pageCode;

     }

     public int getSubpageCode () {

         return subpageCode;

     }

     public int getAllocationLength () {

         return allocationLength;

     }

     public ModePageCode getModePage () {

         return ModePageCode.getModePage(pageCode, subpageCode);

     }

 }