/**
 *  \file 
 *  \author Eduardo Davila and Claire Mouton.
 *  \brief Class bbtk::ThresholdImageView. 
 *  \date September 2012
 */

#include "ColorLayerImageView.h"

#include <vtkImageReslice.h>
#include <vtkLookupTable.h>
#include <vtkImageData.h>

#include <algorithm>


//=========================================================================
//=========================================================================
//=========================================================================
//=========================================================================
ColorLayerImageView::ColorLayerImageView( )
{
  _z2		=	0;
  _fix_dynamic	=	true;
  _color_type   =       false;
}

//=========================================================================
ColorLayerImageView::~ColorLayerImageView()
{
}
//=========================================================================


//----------------------------------------------------------------------------
void ColorLayerImageView::SetSliceFixDynamic(bool fix_dynamic)
{
  _fix_dynamic = fix_dynamic;
}

//----------------------------------------------------------------------------
void ColorLayerImageView::SetZ2(int z2)  
{
  _z2 = z2;
}

//----------------------------------------------------------------------------
int ColorLayerImageView::GetZ() // virtual 
{
  int result=0;
  if (_fix_dynamic==false)
    {
      result = _z2;
    }
  else
    {
      result = LayerImageBase::GetZ();
    }  

  return result;
}

//----------------------------------------------------------------------------
void ColorLayerImageView::SetBaseColors(std::vector<double> & base_color)
{
  // The base color vector must be of a size multiple of 3, not null.
  if (base_color.size() != 0 && base_color.size() % 3 == 0)
    _base_color = base_color;
  // Otherwise, an exception should be thrown.
  else if (base_color.size() != 0)
    std::cout << "CM ColorLayerImageView::SetBaseColors : ERROR!!! The base color vector has an inconsistent size. It must be of a size multiple of 3, different from 0, but its size is: "<< base_color.size() << ". Therefore, the default values will be used as base colors." << std::endl;
}

//----------------------------------------------------------------------------
double ColorLayerImageView::GetBaseColors(unsigned int index)
{
  if (_base_color.size() > index)
    return _base_color.at(index);
  // An exception should be thrown if the index does not exist in the color vector.
  else
    {
      std::cout << "CM ColorLayerImageView::GetBaseColors : ERROR!!! The index " << index << "is out of the base color vector range." << std ::endl;
      return -1.0;
    }
}

//----------------------------------------------------------------------------
void ColorLayerImageView::SetGreyLevelBoundaries(std::vector<double> & grey_level_boundary)
{
  // The size must be greater than or equal to 2 (at least min and max must exist).
  if ( grey_level_boundary.size() >= 2)
    {
      sort ( grey_level_boundary.begin(), grey_level_boundary.end() );
      _grey_level_boundary = grey_level_boundary;
    }
  // Otherwise, an exception should be thrown.
  else if (grey_level_boundary.size() != 0)
    std::cout << "CM ColorLayerImageView::SetGreyLevelBoundaries : ERROR!!! The grey level boundaries vector has an inconsistent size. It must be of a size greater than or equal to 2 (at least min and max must exist), but its size is: " << grey_level_boundary.size() << ". Therefore, the histogram will be equally split." << std::endl;
}

//----------------------------------------------------------------------------
double ColorLayerImageView::GetGreyLevelBoundaries(unsigned int index)
{  
  if (_grey_level_boundary.size() > index)
    return _grey_level_boundary.at(index);
  // An exception should be thrown if the index does not exist in the grey level boundary vector.
  else
    {
      std::cout << "CM ColorLayerImageView::GetGreyLevelBoundaries : ERROR!!! The index " << index << "is out of the grey level boundaries vector range." << std ::endl;
      return -1.0;
    }
}

//----------------------------------------------------------------------------
void ColorLayerImageView::SetPlainOrGradientColor(bool color_type)
{
  _color_type = color_type;
} 

//----------------------------------------------------------------------------
int ColorLayerImageView::GetBaseColorNb()
{
  return _base_color.size()/3;
}

//----------------------------------------------------------------------------
void ColorLayerImageView::SetDefaultGreyLevelBoundary()
{
  // CM Sets the default behaviour concerning the lookup table keeping the base colors already set.
  _grey_level_boundary.clear();

  // This avoids a potential division by 0 through delta during the lookup table configuration.
  if (_range[1]==0)
    {
      _range[1]=255;
    }
	  
  // Grey level extrema are set by default to the image grey level extrema.
  int minTot = floor (_range[0]);
  int maxTot = ceil (_range[1]);

  _grey_level_boundary.push_back((double)minTot);
  
  // By default, the histogram is split into BaseColorNb areas of equal width.
  double delta = (maxTot - minTot)/GetBaseColorNb();
  for (int i = 1; i <= GetBaseColorNb() ; i ++)
    {
      _grey_level_boundary.push_back((double)minTot + i * delta);
    }
}

//----------------------------------------------------------------------------
void ColorLayerImageView::SetDefaultBaseColorAndGreyLevelBoundary()
{
  // CM Sets the default behaviour concerning the lookup table.
  _grey_level_boundary.clear();
  _base_color.clear();
  // Base colors are set to blue, yellow and red.
  // Blue.
  _base_color.push_back(0.0);
  _base_color.push_back(0.0);
  _base_color.push_back(1.0);
  // Yellow.
  _base_color.push_back(1.0);
  _base_color.push_back(1.0);
  _base_color.push_back(0.0);
  // Red.
  _base_color.push_back(1.0);
  _base_color.push_back(0.0);
  _base_color.push_back(0.0);

  // This avoids a potential division by 0 through delta during the lookup table configuration.
  if (_range[1]==0)
    {
      _range[1]=255;
    }
	  
  int minTot = floor (_range[0]);
  int maxTot = ceil (_range[1]);
	  
  _grey_level_boundary.push_back((double)minTot);
 
  // By default, the histogram is split into three areas of equal width.
  double delta = (maxTot - minTot)/3.0;
  _grey_level_boundary.push_back(minTot + delta);
  _grey_level_boundary.push_back(minTot + 2*delta);

  _grey_level_boundary.push_back((double)maxTot);
}

//----------------------------------------------------------------------------
void ColorLayerImageView::ConfigLookupTable()  // virtual
{
  // CM
  // Grey level extrema retrieved from the image grey level extrema.
  GetImage()->GetScalarRange(_range);


  // ------------------ Setting Default Values
  // Checks the size consistency of vectors _base_color and _grey_level_boundary.
  // In case of inconsistency, an exception should be thrown. Instead, the default values are set.
  if (GetBaseColorNb() == 0)
    SetDefaultBaseColorAndGreyLevelBoundary();

  // If at least one color has been set, set the grey level boundaries to build an equipartition of the image grey levels, keeping the base colors defined.
  else
    if (GetBaseColorNb() != (_grey_level_boundary.size() - 1) )
      {
	std::cout << "CM ColorLayerImageView::ConfigLookupTable : ERROR!!! Inconsistency between the sizes of vectors _base_color and _grey_level_boundary. _base_color.size()/3 (=" <<_base_color.size()/3 << ") should be equal to _grey_level_boundary.size() - 1 (=" << _grey_level_boundary.size() - 1 << ")." << std::endl;
	std::cout << "CM The default values for the base colors and the grey level boundaries will be set." << std::endl;
	SetDefaultGreyLevelBoundary();	   
      }
  // ------------------ End Of Setting Default Values


  // ------------------ Defining the Threshold Table
  vtkLookupTable* thresholdTable = GetThresholdTable();

  // CM Number of table values consistent with the effective number of values (see loop below).
  thresholdTable->SetNumberOfTableValues(std::max( GetGreyLevelBoundaries( GetBaseColorNb() ), ceil(_range[1]) ) - std::min(  GetGreyLevelBoundaries(0), floor(_range[0]) ) + 1);
  thresholdTable->SetTableRange(_range); 
  thresholdTable->SetAlphaRange(0, 1);
  thresholdTable->SetValueRange(0, 1);
  thresholdTable->SetSaturationRange(0, 0); 
  thresholdTable->SetRampToLinear( );

  // Defines the lookup table.
  // If the image has a degradation in one (or both) extremum (lower or higher),
  // sets the corresponding grey levels as transparent white in the lookup table.
  for (int i = floor(_range[0]); i <= GetGreyLevelBoundaries(0); i++)
    {
      thresholdTable -> SetTableValue( i, 0, 0, 0, 0);	
    }
  for (int i = GetGreyLevelBoundaries( GetBaseColorNb() ) + 1 ; i <= ceil(_range[1]); i++)
    {
      thresholdTable -> SetTableValue( i, 0, 0, 0, 0);	
    }
	
  int delta;

  // _color_type true, i.e. plain colors.
  // Sets the plain color for each grey level interval.
  if (_color_type)
    {
      for (int i = 0; i < GetBaseColorNb(); i++)
	{
	  delta = GetGreyLevelBoundaries(i+1) - GetGreyLevelBoundaries(i);
	  for (int ii = 1; ii <= delta; ii++)
	    {
	      thresholdTable->SetTableValue(GetGreyLevelBoundaries(i) + ii,
					    GetBaseColors(i*3), 
					    GetBaseColors(i*3 + 1),
					    GetBaseColors(i*3 + 2),
					    1);
	    }
	}
    } // End Of if (_color_type)

	
  // _color_type false, i.e. gradient color
  else
    {
      // First color:
      // Creates a linear range from white to the first color.
      delta = GetGreyLevelBoundaries(1) - GetGreyLevelBoundaries(0);
      for (int ii = 1; ii <= delta ; ii++)
	{
	  thresholdTable->SetTableValue( GetGreyLevelBoundaries(0) + ii, GetBaseColors(0) * ii/delta,
					 GetBaseColors(1) * ii/delta, GetBaseColors(2) * ii/delta, 1);
	}
	    
      // If other colors exist:
      // Creates linear ranges between one color and the following in the color vector.
      if (GetBaseColorNb() > 1)
	{
	  for (int i = 1; i < GetBaseColorNb(); i++)
	    {
	      delta = GetGreyLevelBoundaries(i+1) - GetGreyLevelBoundaries(i);
	      for (int ii = 1; ii <= delta; ii++)
		{
		  // Color computation : previous_color + (current_color - previous_color)/delta * ii
		  thresholdTable->SetTableValue(GetGreyLevelBoundaries(i) + ii,
						GetBaseColors((i-1)*3) + (GetBaseColors(i*3) - GetBaseColors((i-1)*3)) / delta * ii , 
						GetBaseColors((i-1)*3 + 1) + (GetBaseColors(i*3 + 1) - GetBaseColors((i-1)*3 + 1)) / delta * ii ,
						GetBaseColors((i-1)*3 + 2) + (GetBaseColors(i*3 + 2) - GetBaseColors((i-1)*3 + 2)) / delta * ii ,
						1);
		}
	    }
	}
    } //  End Of if (!_color_type)
	
  thresholdTable->Build( );
  // ------------------ End Of Defining the Threshold Table

  //EO CM
}

// EOF