#include <vtkActor.h>
#include <vtkAxes.h>
#include <vtkCamera.h>
#include <vtkContourFilter.h>
#include <vtkDataSet.h>
#include <vtkFloatArray.h>
#include <vtkGaussianSplatter.h>
#include <vtkImageData.h>
#include <vtkNamedColors.h>
#include <vtkPointData.h>
#include <vtkPoints.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h> 
#include <vtkRenderWindowInteractor.h>
#include <vtkSmartPointer.h>
#include <vtkTubeFilter.h>
#include <vtkUnstructuredGrid.h>

#include <algorithm>
#include <array>
#include <string>

namespace
{
vtkSmartPointer<vtkDataSet> ReadFinancialData(const char *fname, const char *x, const char *y, const char *z, const char *s);
int ParseFile(FILE *file, const char *tag, float *data);
}

int main( int argc, char *argv[] )
{
  double bounds[6];

  if (argc < 2)
  {
    std::cout << "Usage: " << argv[0] << " financial_file" << endl;
    return EXIT_FAILURE;
  }
  char* fname = argv[1];

  vtkSmartPointer<vtkNamedColors> colors =
    vtkSmartPointer<vtkNamedColors>::New();

  // Set the color for the population.
  std::array<unsigned char , 4> popColor{{230, 230, 230, 255}};
    colors->SetColor("PopColor", popColor.data());

  // read data
  vtkSmartPointer<vtkDataSet> dataSet =
    ReadFinancialData(fname, "MONTHLY_PAYMENT","INTEREST_RATE",
                      "LOAN_AMOUNT","TIME_LATE");
  // construct pipeline for original population
  vtkSmartPointer<vtkGaussianSplatter> popSplatter =
    vtkSmartPointer<vtkGaussianSplatter>::New();
  popSplatter->SetInputData(dataSet);
  popSplatter->SetSampleDimensions(100, 100, 100);
  popSplatter->SetRadius(0.05);
  popSplatter->ScalarWarpingOff();

  vtkSmartPointer<vtkContourFilter> popSurface =
    vtkSmartPointer<vtkContourFilter>::New();
  popSurface->SetInputConnection(popSplatter->GetOutputPort());
  popSurface->SetValue(0,0.01);

  vtkSmartPointer<vtkPolyDataMapper> popMapper =
    vtkSmartPointer<vtkPolyDataMapper>::New();
  popMapper->SetInputConnection(popSurface->GetOutputPort());
  popMapper->ScalarVisibilityOff();

  vtkSmartPointer<vtkActor> popActor = vtkSmartPointer<vtkActor>::New();
  popActor->SetMapper(popMapper);
  popActor->GetProperty()->SetOpacity(0.3);
  popActor->GetProperty()->SetColor(colors->GetColor3d("popColor").GetData());

  // construct pipeline for delinquent population
  vtkSmartPointer<vtkGaussianSplatter> lateSplatter =
    vtkSmartPointer<vtkGaussianSplatter>::New();
  lateSplatter->SetInputData(dataSet);
  lateSplatter->SetSampleDimensions(50,50,50);
  lateSplatter->SetRadius(0.05);
  lateSplatter->SetScaleFactor(0.005);

  vtkSmartPointer<vtkContourFilter> lateSurface =
    vtkSmartPointer<vtkContourFilter>::New();
  lateSurface->SetInputConnection(lateSplatter->GetOutputPort());
  lateSurface->SetValue(0,0.01);

  vtkSmartPointer<vtkPolyDataMapper> lateMapper =
    vtkSmartPointer<vtkPolyDataMapper>::New();
  lateMapper->SetInputConnection(lateSurface->GetOutputPort());
  lateMapper->ScalarVisibilityOff();

  vtkSmartPointer<vtkActor> lateActor =
    vtkSmartPointer<vtkActor>::New();
  lateActor->SetMapper(lateMapper);
  lateActor->GetProperty()->SetColor(colors->GetColor3d("Red").GetData());

  // create axes
  popSplatter->Update();
  popSplatter->GetOutput()->GetBounds(bounds);

  vtkSmartPointer<vtkAxes> axes =
    vtkSmartPointer<vtkAxes>::New();
  axes->SetOrigin(bounds[0], bounds[2], bounds[4]);
  axes->SetScaleFactor(popSplatter->GetOutput()->GetLength()/5);

  vtkSmartPointer<vtkTubeFilter> axesTubes =
    vtkSmartPointer<vtkTubeFilter>::New();
  axesTubes->SetInputConnection(axes->GetOutputPort());
  axesTubes->SetRadius(axes->GetScaleFactor()/25.0);
  axesTubes->SetNumberOfSides(6);

  vtkSmartPointer<vtkPolyDataMapper> axesMapper =
    vtkSmartPointer<vtkPolyDataMapper>::New();
  axesMapper->SetInputConnection(axesTubes->GetOutputPort());

  vtkSmartPointer<vtkActor> axesActor =
    vtkSmartPointer<vtkActor>::New();
  axesActor->SetMapper(axesMapper);

  // graphics stuff
  vtkSmartPointer<vtkRenderer> renderer =
    vtkSmartPointer<vtkRenderer>::New();

  vtkSmartPointer<vtkRenderWindow> renWin =
    vtkSmartPointer<vtkRenderWindow>::New();
  renWin->AddRenderer(renderer);

  vtkSmartPointer<vtkRenderWindowInteractor> interactor =
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  interactor->SetRenderWindow(renWin);

  //set up renderer
  renderer->AddActor(lateActor);
  renderer->AddActor(axesActor);
  renderer->AddActor(popActor);
  renderer->SetBackground(colors->GetColor3d("Wheat").GetData());
  renWin->SetSize(640, 480);

  renderer->ResetCamera();
  renderer->GetActiveCamera()->Dolly(1.3);
  renderer->ResetCameraClippingRange();

  // interact with data
  renWin->Render();
  interactor->Start();

  return EXIT_SUCCESS;
}

namespace
{
vtkSmartPointer<vtkDataSet> ReadFinancialData(const char* filename, const char *x, const char *y, const char *z, const char *s)
{
  float xyz[3];
  FILE *file;
  int i, npts;
  char tag[80];

  if ( (file = fopen(filename,"r")) == 0 )
  {
    std::cerr << "ERROR: Can't open file: " << filename << std::endl;
    return NULL;
  }

  int n = fscanf (file, "%s %d", tag, &npts); // read number of points
  if (n != 2)
  {
    std::cerr << "ERROR: Can't read file: " << filename << std::endl;
    fclose(file);
    return NULL;
  }
  // Check for a reasonable npts
  if (npts <= 0)
  {
    std::cerr << "ERROR: Number of points must be greater that 0" << std::endl;
    fclose(file);
    return NULL;
  }
  // We arbitrarily pick a large upper limit on npts
  if (npts > VTK_INT_MAX / 10)
  {
    std::cerr << "ERROR: npts (" << npts << ") is unreasonably large" << std::endl;
    fclose(file);
    return NULL;
  }
  vtkSmartPointer<vtkUnstructuredGrid> dataSet =
    vtkSmartPointer<vtkUnstructuredGrid>::New();
  float *xV = new float[npts];
  float *yV = new float[npts];
  float *zV = new float[npts];
  float *sV = new float[npts];

  if ( ! ParseFile(file, x, xV) || ! ParseFile(file, y, yV) ||
       ! ParseFile(file, z, zV) || ! ParseFile(file, s, sV) )
  {
    std::cerr << "ERROR: Couldn't read data!" << std::endl;
    delete [] xV;
    delete [] yV;
    delete [] zV;
    delete [] sV;
    fclose(file);
    return NULL;
  }

  vtkSmartPointer<vtkPoints> newPts =
    vtkSmartPointer<vtkPoints>::New();
  vtkSmartPointer<vtkFloatArray> newScalars =
    vtkSmartPointer<vtkFloatArray>::New();

  for (i=0; i<npts; i++)
  {
    xyz[0] = xV[i]; xyz[1] = yV[i]; xyz[2] = zV[i];
//     std::cout << xV[i] << " " << yV[i] << " " << zV[i] << std::endl;
    newPts->InsertPoint(i, xyz);
    newScalars->InsertValue(i, sV[i]);
  }

  dataSet->SetPoints(newPts);
  dataSet->GetPointData()->SetScalars(newScalars);

  // cleanup
  delete [] xV;
  delete [] yV;
  delete [] zV;
  delete [] sV;
  fclose(file);

  return dataSet;
}

int ParseFile(FILE *file, const char *label, float *data)
{
  char tag[80];
  int i, npts, readData=0;
  float min=VTK_FLOAT_MAX;
  float max=(-VTK_FLOAT_MAX);

  if ( file == NULL || label == NULL ) return 0;

  rewind(file);

  if (fscanf(file, "%s %d", tag, &npts) != 2)
  {
    std::cerr << "ERROR: IO Error " << __FILE__ << ":" << __LINE__ << std::endl;
    return 0;
  }
  while ( !readData && fscanf(file, "%s", tag) == 1 )
  {
    if ( ! strcmp(tag,label) )
    {
      readData = 1;
      for (i=0; i<npts; i++)
      {
        if (fscanf(file, "%f", data+i) != 1)
        {
          std::cerr << "ERROR: IO Error " << __FILE__ << ":" << __LINE__ << std::endl;
          return 0;
        }
        if ( data[i] < min ) min = data[i];
         if ( data[i] > min ) max = data[i]; // bug here
        // Should be:
        // if ( data[i] > max ) max = data[i]; 
      }
      // normalize data
      for (i=0; i<npts; i++) data[i] = min + data[i]/(max-min);
    }
    else
    {
      for (i=0; i<npts; i++)
      {
        if (fscanf(file, "%*f") != 0)
        {
          std::cerr << "ERROR: IO Error " << __FILE__ << ":" << __LINE__ << std::endl;
          return 0;
        }
      }
    }
  }

  if ( ! readData ) return 0;
  else return 1;
}
}
