// SPDX-FileCopyrightText: Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
// SPDX-License-Identifier: BSD-3-Clause
#include "vtkSmartPointer.h"

#include "vtkDoubleArray.h"
#include "vtkImageData.h"
#include "vtkImageMathematics.h"
#include "vtkImageReader.h"
#include "vtkImageShiftScale.h"
#include "vtkImageWeightedSum.h"
#include "vtkStructuredPointsWriter.h"

#include "vtkTestUtilities.h"

#include <iostream>

int ImageWeightedSum(int argc, char* argv[])
{
  int rval = 0;
  char* fname = vtkTestUtilities::ExpandDataFileName(argc, argv, "Data/headsq/quarter");

  vtkSmartPointer<vtkImageReader> reader = vtkSmartPointer<vtkImageReader>::New();
  reader->SetDataByteOrderToLittleEndian();
  reader->SetDataExtent(0, 63, 0, 63, 1, 93);
  reader->SetDataSpacing(3.2, 3.2, 1.5);
  reader->SetFilePrefix(fname);
  reader->SetDataMask(0x7fff);

  delete[] fname;

  // Test when weight is equal to 0
  vtkSmartPointer<vtkImageWeightedSum> sum = vtkSmartPointer<vtkImageWeightedSum>::New();
  sum->SetWeight(0, 0.);
  sum->AddInputConnection(reader->GetOutputPort());
  sum->Update();
  double range[2];
  sum->GetOutput()->GetScalarRange(range);
  if (range[0] != 0 || range[1] != 0)
  {
    std::cerr << "Range: " << range[0] << "," << range[1] << std::endl;
    rval++;
  }

  // Set dummy values
  vtkSmartPointer<vtkDoubleArray> weights = vtkSmartPointer<vtkDoubleArray>::New();
  weights->SetNumberOfTuples(5);
  weights->SetValue(0, 10.0);
  weights->SetValue(1, 20.0);
  weights->SetValue(2, 30.0);
  weights->SetValue(3, 40.0);
  weights->SetValue(4, 50.0);

  // Pass in the same images multiple times
  sum->RemoveAllInputs();
  sum->SetWeights(weights);
  sum->AddInputConnection(reader->GetOutputPort());
  sum->AddInputConnection(reader->GetOutputPort());
  sum->AddInputConnection(reader->GetOutputPort());
  sum->AddInputConnection(reader->GetOutputPort());
  sum->AddInputConnection(reader->GetOutputPort());

  // Subtract the original image
  vtkSmartPointer<vtkImageMathematics> math = vtkSmartPointer<vtkImageMathematics>::New();
  math->SetOperationToSubtract();
  math->SetInputConnection(0, reader->GetOutputPort());
  math->SetInputConnection(1, sum->GetOutputPort());
  math->Update();

  math->GetOutput()->GetScalarRange(range);
  if (range[0] != 0 || range[1] != 0)
  {
    std::cerr << "Range: " << range[0] << "," << range[1] << std::endl;
    rval++;
  }

  // Get scalar range:
  reader->GetOutput()->GetScalarRange(range);
  vtkSmartPointer<vtkImageShiftScale> shift = vtkSmartPointer<vtkImageShiftScale>::New();
  shift->SetInputConnection(reader->GetOutputPort());
  shift->SetScale(1. / (range[1] - range[0]));
  shift->SetShift(-range[0]);
  shift->SetOutputScalarTypeToDouble();

  // Test multiple scalar type inputs
  sum->RemoveAllInputs();
  weights->SetNumberOfTuples(2);
  weights->SetValue(0, 0.0);
  weights->SetValue(1, 1.0);
  sum->AddInputConnection(reader->GetOutputPort());
  sum->AddInputConnection(shift->GetOutputPort());

  math->SetInputConnection(0, shift->GetOutputPort());
  math->SetInputConnection(1, sum->GetOutputPort());

  return rval;
}