/*=========================================================================

  Program: GDCM (Grassroots DICOM). A DICOM library

  Copyright (c) 2006-2011 Mathieu Malaterre
  All rights reserved.
  See Copyright.txt or http://gdcm.sourceforge.net/Copyright.html for details.

     This software is distributed WITHOUT ANY WARRANTY; without even
     the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR
     PURPOSE.  See the above copyright notice for more information.

=========================================================================*/
#include "gdcmFileDecompressLookupTable.h"
#include "gdcmAttribute.h"

#include <cstring>
#include <limits>

namespace gdcm
{

bool FileDecompressLookupTable::Change()
{
  DataSet &ds = F->GetDataSet();
  PixelFormat pf = PixelData->GetPixelFormat();
  PhotometricInterpretation pi = PixelData->GetPhotometricInterpretation();
    if ( pi == PhotometricInterpretation::PALETTE_COLOR )
      {
      const LookupTable &lut = PixelData->GetLUT();
      assert( lut.Initialized() );
//      assert( (pf.GetBitsAllocated() == 8  && pf.GetPixelRepresentation() == 0)
//           || (pf.GetBitsAllocated() == 16 && pf.GetPixelRepresentation() == 0) );
      // lut descriptor:
      // (0028,1101) US 256\0\16                                 #   6, 3 RedPaletteColorLookupTableDescriptor
      // (0028,1102) US 256\0\16                                 #   6, 3 GreenPaletteColorLookupTableDescriptor
      // (0028,1103) US 256\0\16                                 #   6, 3 BluePaletteColorLookupTableDescriptor
      // lut data:
      unsigned short length, subscript, bitsize;
      unsigned short rawlut8[256];
      unsigned short rawlut16[65536];
      unsigned short *rawlut = rawlut8;
      unsigned int lutlen = 256;
      if( pf.GetBitsAllocated() == 16 )
        {
        rawlut = rawlut16;
        lutlen = 65536;
        }
      unsigned int l;

      // FIXME: should I really clear rawlut each time ?
      // RED
      memset(rawlut,0,lutlen*2);
      lut.GetLUT(LookupTable::RED, (unsigned char*)rawlut, l);
      DataElement redde( Tag(0x0028, 0x1201) );
      redde.SetVR( VR::OW );
      redde.SetByteValue( (char*)rawlut, l);
      ds.Replace( redde );
      // descriptor:
      Attribute<0x0028, 0x1101, VR::US, VM::VM3> reddesc;
      lut.GetLUTDescriptor(LookupTable::RED, length, subscript, bitsize);
      reddesc.SetValue(length,0); reddesc.SetValue(subscript,1); reddesc.SetValue(bitsize,2);
      ds.Replace( reddesc.GetAsDataElement() );

      // GREEN
      memset(rawlut,0,lutlen*2);
      lut.GetLUT(LookupTable::GREEN, (unsigned char*)rawlut, l);
      DataElement greende( Tag(0x0028, 0x1202) );
      greende.SetVR( VR::OW );
      greende.SetByteValue( (char*)rawlut, l);
      ds.Replace( greende );
      // descriptor:
      Attribute<0x0028, 0x1102, VR::US, VM::VM3> greendesc;
      lut.GetLUTDescriptor(LookupTable::GREEN, length, subscript, bitsize);
      greendesc.SetValue(length,0); greendesc.SetValue(subscript,1); greendesc.SetValue(bitsize,2);
      ds.Replace( greendesc.GetAsDataElement() );

      // BLUE
      memset(rawlut,0,lutlen*2);
      lut.GetLUT(LookupTable::BLUE, (unsigned char*)rawlut, l);
      DataElement bluede( Tag(0x0028, 0x1203) );
      bluede.SetVR( VR::OW );
      bluede.SetByteValue( (char*)rawlut, l);
      ds.Replace( bluede );
      // descriptor:
      Attribute<0x0028, 0x1103, VR::US, VM::VM3> bluedesc;
      lut.GetLUTDescriptor(LookupTable::BLUE, length, subscript, bitsize);
      bluedesc.SetValue(length,0); bluedesc.SetValue(subscript,1); bluedesc.SetValue(bitsize,2);
      ds.Replace( bluedesc.GetAsDataElement() );

    ds.Remove( Tag(0x0028, 0x1221) );
    ds.Remove( Tag(0x0028, 0x1222) );
    ds.Remove( Tag(0x0028, 0x1223) );


  return true;
      }
  return false;
}


} // end namespace gdcm