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

  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 "gdcmOverlay.h"
#include "gdcmTag.h"
#include "gdcmDataElement.h"
#include "gdcmDataSet.h"
#include "gdcmAttribute.h"

#include <vector>

namespace gdcm
{

class OverlayInternal
{
public:
  OverlayInternal():
  InPixelData(false),
  Group(0), // invalid default
  Rows(0),
  Columns(0),
  NumberOfFrames(0),
  Description(),
  Type(),
  //Origin[2],
  FrameOrigin(0),
  BitsAllocated(0),
  BitPosition(0),
  Data() { Origin[0] = Origin[1] = 0; }
  /*
  (6000,0010) US 484                                      #   2, 1 OverlayRows
  (6000,0011) US 484                                      #   2, 1 OverlayColumns
  (6000,0015) IS [1]                                      #   2, 1 NumberOfFramesInOverlay
  (6000,0022) LO [Siemens MedCom Object Graphics]         #  30, 1 OverlayDescription
  (6000,0040) CS [G]                                      #   2, 1 OverlayType
  (6000,0050) SS 1\1                                      #   4, 2 OverlayOrigin
  (6000,0051) US 1                                        #   2, 1 ImageFrameOrigin
  (6000,0100) US 1                                        #   2, 1 OverlayBitsAllocated
  (6000,0102) US 0                                        #   2, 1 OverlayBitPosition
  (6000,3000) OW 0000\0000\0000\0000\0000\0000\0000\0000\0000\0000\0000\0000\0000... # 29282, 1 OverlayData
  */

  bool InPixelData;
// Identifier need to be in the [6000,60FF] range (no odd number):
  unsigned short Group;
// Descriptor:
  unsigned short Rows;           // (6000,0010) US 484                                      #   2, 1 OverlayRows
  unsigned short Columns;        // (6000,0011) US 484                                      #   2, 1 OverlayColumns
  unsigned int   NumberOfFrames; // (6000,0015) IS [1]                                      #   2, 1 NumberOfFramesInOverlay
  std::string    Description;    // (6000,0022) LO [Siemens MedCom Object Graphics]         #  30, 1 OverlayDescription
  std::string    Type;           // (6000,0040) CS [G]                                      #   2, 1 OverlayType
  signed short   Origin[2];      // (6000,0050) SS 1\1                                      #   4, 2 OverlayOrigin
  unsigned short FrameOrigin;    // (6000,0051) US 1                                        #   2, 1 ImageFrameOrigin
  unsigned short BitsAllocated;  // (6000,0100) US 1                                        #   2, 1 OverlayBitsAllocated
  unsigned short BitPosition;    // (6000,0102) US 0                                        #   2, 1 OverlayBitPosition
  //std::vector<bool> Data;
  std::vector<char> Data;
  void Print(std::ostream &os) const {
    os << "Group           0x" <<  std::hex << Group << std::dec << std::endl;
    os << "Rows            " <<  Rows << std::endl;
    os << "Columns         " <<  Columns << std::endl;
    os << "NumberOfFrames  " <<  NumberOfFrames << std::endl;
    os << "Description     " <<  Description << std::endl;
    os << "Type            " <<  Type << std::endl;
    os << "Origin[2]       " <<  Origin[0] << "," << Origin[1] << std::endl;
    os << "FrameOrigin     " <<  FrameOrigin << std::endl;
    os << "BitsAllocated   " <<  BitsAllocated << std::endl;
    os << "BitPosition     " <<  BitPosition << std::endl;
    //std::vector<bool> Data;
  }
};

Overlay::Overlay()
{
  Internal = new OverlayInternal;
}

Overlay::~Overlay()
{
  delete Internal;
}

Overlay::Overlay(Overlay const &ov):Object(ov)
{
  //delete Internal;
  Internal = new OverlayInternal;
  // TODO: copy OverlayInternal into other...
  *Internal = *ov.Internal;
}

unsigned int Overlay::GetNumberOfOverlays(DataSet const & ds)
{
  Tag overlay(0x6000,0x0000); // First possible overlay
  bool finished = false;
  unsigned int numoverlays = 0;
  while( !finished )
    {
    const DataElement &de = ds.FindNextDataElement( overlay );
    if( de.GetTag().GetGroup() > 0x60FF ) // last possible curve
      {
      finished = true;
      }
    else if( de.GetTag().IsPrivate() )
      {
      // Move on to the next public one:
      overlay.SetGroup( de.GetTag().GetGroup() + 1 );
      overlay.SetElement( 0 ); // reset just in case...
      }
    else
      {
      // Yeah this is a potential overlay element, let's check this is not a broken LEADTOOL image,
      // or prova0001.dcm:
      // (5000,0000) UL 0                                        #   4, 1 GenericGroupLength
      // (6000,0000) UL 0                                        #   4, 1 GenericGroupLength
      // (6001,0000) UL 28                                       #   4, 1 PrivateGroupLength
      // (6001,0010) LT [PAPYRUS 3.0]                            #  12, 1 PrivateCreator
      // (6001,1001) LT (no value available)                     #   0, 0 Unknown Tag & Data
/*
 * FIXME:
 * In order to support : gdcmData/SIEMENS_GBS_III-16-ACR_NEMA_1.acr
 *                       gdcmDataExtra/gdcmSampleData/images_of_interest/XA_GE_JPEG_02_with_Overlays.dcm
 * I cannot simply check for overlay_group,3000 this would not work
 * I would need a strong euristick
 */
      // Store found tag in overlay:
      overlay = de.GetTag();
      // heuristic based on either the Overlay Data or the Col/Row info
      Tag toverlaydata(overlay.GetGroup(),0x3000 );
      Tag toverlayrows(overlay.GetGroup(),0x0010 );
      Tag toverlaycols(overlay.GetGroup(),0x0011 );
      Tag toverlaybitpos(overlay.GetGroup(),0x0102 );
      if( ds.FindDataElement( toverlaydata ) )
        {
        // ok so far so good...
        const DataElement& overlaydata = ds.GetDataElement( toverlaydata );
        //const DataElement& overlaydata = ds.GetDataElement(Tag(overlay.GetGroup(),0x0010));
        if( !overlaydata.IsEmpty() )
          {
          ++numoverlays;
          }
        }
      else if( ds.FindDataElement( toverlayrows ) && ds.FindDataElement( toverlaycols )
        && ds.FindDataElement( toverlaybitpos ) )
        {
        // Overlay Pixel are in Unused Pixel
        assert( !ds.FindDataElement( toverlaydata ) );
        const DataElement& overlayrows = ds.GetDataElement( toverlayrows );
        const DataElement& overlaycols = ds.GetDataElement( toverlaycols );
        assert( ds.FindDataElement( toverlaybitpos ) );
        const DataElement& overlaybitpos = ds.GetDataElement( toverlaybitpos );
        if( !overlayrows.IsEmpty() && !overlaycols.IsEmpty() && !overlaybitpos.IsEmpty() )
          {
          ++numoverlays;
          }
        }
        // Move on to the next possible one:
        overlay.SetGroup( overlay.GetGroup() + 2 );
        // reset to element 0x0 just in case...
        overlay.SetElement( 0 );
      }
    }

  // at most one out of two :
  assert( numoverlays < 0x00ff / 2 );
  // PS 3.3 - 2004:
  // C.9.2 Overlay plane module
  // Each Overlay Plane is one bit deep. Sixteen separate Overlay Planes may be associated with an
  // Image or exist as Standalone Overlays in a Series
  assert( numoverlays <= 16 );
  return numoverlays;
}

void Overlay::Update(const DataElement & de)
{
/*
  8.1.2 Overlay data encoding of related data elements
    Encoded Overlay Planes always have a bit depth of 1, and are encoded separately from the Pixel Data in Overlay Data (60xx,3000). The following two Data Elements shall define the Overlay Plane structure:
    ¿ Overlay Bits Allocated (60xx,0100)
    ¿ Overlay Bit Position (60xx,0102)
    Notes: 1. There is no Data Element analogous to Bits Stored (0028,0101) since Overlay Planes always have a bit depth of 1.
    2. Restrictions on the allowed values for these Data Elements are defined in PS 3.3. Formerly overlay data stored in unused bits of Pixel Data (7FE0,0010) was described, and these attributes had meaningful values but this usage has been retired. See PS 3.5 2004. For overlays encoded in Overlay Data Element (60xx,3000), Overlay Bits Allocated (60xx,0100) is always 1 and Overlay Bit Position (60xx,0102) is always 0.
*/

  assert( de.GetTag().IsPublic() );
  const ByteValue* bv = de.GetByteValue();
  if( !bv ) return; // Discard any empty element (will default to another value)
  assert( bv->GetPointer() && bv->GetLength() );
  std::string s( bv->GetPointer(), bv->GetLength() );
  // What if a \0 can be found before the end of string...
  //assert( strlen( s.c_str() ) == s.size() );

  // First thing check consistency:
  if( !GetGroup() )
    {
    SetGroup( de.GetTag().GetGroup() );
    }
  else // check consistency
    {
    assert( GetGroup() == de.GetTag().GetGroup() ); // programmer error
    }

  //std::cerr << "Tag: " << de.GetTag() << std::endl;
  if( de.GetTag().GetElement() == 0x0000 ) // OverlayGroupLength
    {
    // ??
    }
  else if( de.GetTag().GetElement() == 0x0010 ) // OverlayRows
    {
    Attribute<0x6000,0x0010> at;
    at.SetFromDataElement( de );
    SetRows( at.GetValue() );
    }
  else if( de.GetTag().GetElement() == 0x0011 ) // OverlayColumns
    {
    Attribute<0x6000,0x0011> at;
    at.SetFromDataElement( de );
    SetColumns( at.GetValue() );
    }
  else if( de.GetTag().GetElement() == 0x0015 ) // NumberOfFramesInOverlay
    {
    Attribute<0x6000,0x0015> at;
    at.SetFromDataElement( de );
    SetNumberOfFrames( at.GetValue() );
    }
  else if( de.GetTag().GetElement() == 0x0022 ) // OverlayDescription
    {
    SetDescription( s.c_str() );
    }
  else if( de.GetTag().GetElement() == 0x0040 ) // OverlayType
    {
    SetType( s.c_str() );
    }
  else if( de.GetTag().GetElement() == 0x0045 ) // OverlaySubtype
    {
    gdcmWarningMacro( "FIXME" );
    }
  else if( de.GetTag().GetElement() == 0x0050 ) // OverlayOrigin
    {
    Attribute<0x6000,0x0050> at;
    at.SetFromDataElement( de );
    SetOrigin( at.GetValues() );
    }
  else if( de.GetTag().GetElement() == 0x0051 ) // ImageFrameOrigin
    {
    Attribute<0x6000,0x0051> at;
    at.SetFromDataElement( de );
    SetFrameOrigin( at.GetValue() );
    }
  else if( de.GetTag().GetElement() == 0x0060 ) // OverlayCompressionCode (RET)
    {
    assert( s == "NONE" ); // FIXME ??
    }
  else if( de.GetTag().GetElement() == 0x0100 ) // OverlayBitsAllocated
    {
    Attribute<0x6000,0x0100> at;
    at.SetFromDataElement( de );
    // if OverlayBitsAllocated is 1 it imply OverlayData element
    // if OverlayBitsAllocated is 16 it imply Overlay in unused pixel bits
    if( at.GetValue() != 1 )
      {
      gdcmWarningMacro( "Unsuported OverlayBitsAllocated: " << at.GetValue() );
      }
    SetBitsAllocated( at.GetValue() );
    }
  else if( de.GetTag().GetElement() == 0x0102 ) // OverlayBitPosition
    {
    Attribute<0x6000,0x0102> at;
    at.SetFromDataElement( de );
    if( at.GetValue() != 0 ) // For old ACR when using unused bits...
      {
      gdcmDebugMacro( "Unsuported OverlayBitPosition: " << at.GetValue() );
      }
    SetBitPosition( at.GetValue() );
    }
  else if( de.GetTag().GetElement() == 0x0110 ) // OverlayFormat (RET)
    {
    assert( s == "RECT" );
    }
  else if( de.GetTag().GetElement() == 0x0200 ) // OverlayLocation (RET)
    {
    Attribute<0x6000,0x0200> at;
    at.SetFromDataElement( de );
    gdcmWarningMacro( "FIXME: " << at.GetValue() );
    }
  else if( de.GetTag().GetElement() == 0x1301 ) // ROIArea
    {
    gdcmWarningMacro( "FIXME" );
    }
  else if( de.GetTag().GetElement() == 0x1302 ) // ROIMean
    {
    gdcmWarningMacro( "FIXME" );
    }
  else if( de.GetTag().GetElement() == 0x1303 ) // ROIStandardDeviation
    {
    gdcmWarningMacro( "FIXME" );
    }
  else if( de.GetTag().GetElement() == 0x1500 ) // OverlayLabel
    {
    gdcmWarningMacro( "FIXME" );
    }
  else if( de.GetTag().GetElement() == 0x3000 ) // OverlayData
    {
    SetOverlay(bv->GetPointer(), bv->GetLength());
    }
  else
    {
    gdcmErrorMacro( "Tag is not supported: " << de.GetTag() << std::endl );
    assert(0);
    }
}

bool Overlay::GrabOverlayFromPixelData(DataSet const &ds)
{
  const unsigned int ovlength = Internal->Rows * Internal->Columns / 8;
  Internal->Data.resize( ovlength ); // set to 0
  if( Internal->BitsAllocated == 16 )
    {
    //assert( Internal->BitPosition >= 12 );
    assert( ds.FindDataElement( Tag(0x7fe0,0x0010) ) );
    const DataElement &pixeldata = ds.GetDataElement( Tag(0x7fe0,0x0010) );
    const ByteValue *bv = pixeldata.GetByteValue();
    if( !bv )
      {
      // XA_GE_JPEG_02_with_Overlays.dcm
      return false;
      }
    assert( bv );
    const char *array = bv->GetPointer();
    // SIEMENS_GBS_III-16-ACR_NEMA_1.acr is pain to support,
    // I cannot simply use the bv->GetLength I have to use the image dim:
    const unsigned int length = ovlength * 8 * 2; //bv->GetLength();
    const uint16_t *p = (uint16_t*)array;
    const uint16_t *end = (uint16_t*)(array + length);
    //const unsigned int ovlength = length / (8*2);
    assert( 8 * ovlength == (unsigned int)Internal->Rows * Internal->Columns );
    if( Internal->Data.empty() )
      {
      return false;
      }
    unsigned char * overlay = (unsigned char*)&Internal->Data[0];
    int c = 0;
    uint16_t pmask = 1 << Internal->BitPosition;
    assert( length / 2 == ovlength * 8 );
    while( p != end )
      {
      const uint16_t val = *p & pmask;
      assert( val == 0x0 || val == pmask );
      // 128 -> 0x80
      if( val )
        {
        overlay[ c / 8 ] |= (0x1 << c%8);
        }
      else
        {
        // else overlay[ c / 8 ] is already 0
        }
      ++p;
      ++c;
      }
    assert( (unsigned)c / 8 == ovlength );
    }
  else
    {
    gdcmErrorMacro( "Could not grab Overlay from image. Please report." );
    return false;
    }
  return true;
}

void Overlay::SetGroup(unsigned short group) { Internal->Group = group; }
unsigned short Overlay::GetGroup() const { return Internal->Group; }

void Overlay::SetRows(unsigned short rows) { Internal->Rows = rows; }
unsigned short Overlay::GetRows() const { return Internal->Rows; }
void Overlay::SetColumns(unsigned short columns) { Internal->Columns = columns; }
unsigned short Overlay::GetColumns() const { return Internal->Columns; }
void Overlay::SetNumberOfFrames(unsigned int numberofframes) { Internal->NumberOfFrames = numberofframes; }
void Overlay::SetDescription(const char* description) { Internal->Description = description; }
const char *Overlay::GetDescription() const { return Internal->Description.c_str(); }
void Overlay::SetType(const char* type) { Internal->Type = type; }
const char *Overlay::GetType() const { return Internal->Type.c_str(); }
void Overlay::SetOrigin(const signed short *origin)
{
  Internal->Origin[0] = origin[0];
  Internal->Origin[1] = origin[1];
}
const signed short * Overlay::GetOrigin() const
{
  return &Internal->Origin[0];
}
void Overlay::SetFrameOrigin(unsigned short frameorigin) { Internal->FrameOrigin = frameorigin; }
void Overlay::SetBitsAllocated(unsigned short bitsallocated) { Internal->BitsAllocated = bitsallocated; }
unsigned short Overlay::GetBitsAllocated() const { return Internal->BitsAllocated; }
void Overlay::SetBitPosition(unsigned short bitposition) { Internal->BitPosition = bitposition; }
unsigned short Overlay::GetBitPosition() const { return Internal->BitPosition; }

bool Overlay::IsEmpty() const
{
  return Internal->Data.empty();
}
bool Overlay::IsZero() const
{
  if( IsEmpty() ) return false;

  std::vector<char>::const_iterator it = Internal->Data.begin();
  for(; it != Internal->Data.end(); ++it )
    {
    if( *it ) return true;
    }
  return false;
}
bool Overlay::IsInPixelData() const { return Internal->InPixelData; }
void Overlay::IsInPixelData(bool b) { Internal->InPixelData = b; }

/*
 * row,col = 400,400   => 20000
 * row,col = 1665,1453 => 302406
 * row,col = 20,198    => 495 words + 1 dicom \0 padding
 */
inline unsigned int compute_bit_and_dicom_padding(unsigned short rows, unsigned short columns)
{
  unsigned int word_padding = ( rows * columns + 7 ) / 8; // need to send full word (8bits at a time)
  return word_padding + word_padding%2; // Cannot have odd length
}

void Overlay::SetOverlay(const char *array, unsigned int length)
{
  if( !array || length == 0 ) return;
  //char * p = (char*)&Internal->Data[0];
  unsigned int computed_length = (Internal->Rows * Internal->Columns + 7) / 8;
  Internal->Data.resize( computed_length ); // filled with 0 if length < computed_length
  if( length < computed_length )
    {
    gdcmWarningMacro( "Not enough data found in Overlay. Proceed with caution" );
    std::copy(array, array+length, Internal->Data.begin());
    }
  else
    {
    if( length > computed_length )
      {
      gdcmWarningMacro( "Too much data found in Overlay. Discarding extra data: " << (length - computed_length) << " bytes." );
      }
    // do not try to copy more than allocated:
    std::copy(array, array+computed_length, Internal->Data.begin());
    }
  /* warning need to take into account padding to the next word (8bits) */
  //assert( length == compute_bit_and_dicom_padding(Internal->Rows, Internal->Columns) );
  assert( Internal->Data.size() == computed_length );
}

const ByteValue &Overlay::GetOverlayData() const
{
  static ByteValue bv;
  bv = ByteValue( Internal->Data );
  return bv;
}

void Overlay::Decode(std::istream &is, std::ostream &os)
{
  unsigned char packedbytes;
  unsigned char unpackedbytes[8];
  while( is.read((char*)&packedbytes,1) )
    {
    unsigned char mask = 1;
    for (unsigned int i = 0; i < 8; ++i)
      {
      if ( (packedbytes & mask) == 0)
        {
        unpackedbytes[i] = 0;
        }
      else
        {
        unpackedbytes[i] = 1;
        }
      mask <<= 1;
      }
    os.write(reinterpret_cast<char*>(unpackedbytes), 8);
    }
}

bool Overlay::GetBuffer(char *buffer) const
{
  size_t length = Internal->Data.size();
  std::copy(buffer, buffer+length, Internal->Data.begin());
  return true;
}

bool Overlay::GetUnpackBuffer(unsigned char *buffer) const
{
  unsigned char *unpackedbytes = buffer;
  for( std::vector<char>::const_iterator it = Internal->Data.begin(); it != Internal->Data.end(); ++it )
    {
    // const unsigned char &packedbytes = *it;
    // weird bug with gcc 3.3 (prerelease on SuSE) apparently:
    unsigned char packedbytes = static_cast<unsigned char>(*it);
    unsigned char mask = 1;
    for (unsigned int i = 0; i < 8; ++i)
      {
      if ( (packedbytes & mask) == 0)
        {
        *unpackedbytes = 0;
        }
      else
        {
        *unpackedbytes = 255;
        }
      ++unpackedbytes;
      mask <<= 1;
      }
    }
  return true;
}

void Overlay::Decompress(std::ostream &os) const
{
  unsigned char unpackedbytes[8];
  for( std::vector<char>::const_iterator it = Internal->Data.begin(); it != Internal->Data.end(); ++it )
    {
    unsigned char packedbytes = *it;
    unsigned char mask = 1;
    for (unsigned int i = 0; i < 8; ++i)
      {
      if ( (packedbytes & mask) == 0)
        {
        unpackedbytes[i] = 0;
        }
      else
        {
        unpackedbytes[i] = 255;
        }
      mask <<= 1;
      }
    os.write(reinterpret_cast<char*>(unpackedbytes), 8);
    }
}

void Overlay::Print(std::ostream &os) const
{
  Internal->Print( os );
}

} // end namespace gdcm
