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

  Program:   Visualization Toolkit
  Module:    vtkStructuredGridOutlineFilter.cxx

  Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
  All rights reserved.
  See Copyright.txt or http://www.kitware.com/Copyright.htm 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 "vtkStructuredGridOutlineFilter.h"

#include "vtkCellArray.h"
#include "vtkInformation.h"
#include "vtkInformationVector.h"
#include "vtkObjectFactory.h"
#include "vtkPolyData.h"
#include "vtkStreamingDemandDrivenPipeline.h"
#include "vtkStructuredGrid.h"

vtkStandardNewMacro(vtkStructuredGridOutlineFilter);

//----------------------------------------------------------------------------
// ComputeDivisionExtents has done most of the work for us.
// Now just connect the points.
int vtkStructuredGridOutlineFilter::RequestData(
  vtkInformation *vtkNotUsed(request),
  vtkInformationVector **inputVector,
  vtkInformationVector *outputVector)
{
  // get the info objects
  vtkInformation *inInfo = inputVector[0]->GetInformationObject(0);
  vtkInformation *outInfo = outputVector->GetInformationObject(0);

  // get the input and output
  vtkStructuredGrid *input = vtkStructuredGrid::SafeDownCast(
    inInfo->Get(vtkDataObject::DATA_OBJECT()));
  vtkPolyData *output = vtkPolyData::SafeDownCast(
    outInfo->Get(vtkDataObject::DATA_OBJECT()));

  int *ext, *wExt, cExt[6];
  int xInc, yInc, zInc;
  vtkPoints *inPts;
  vtkPoints *newPts;
  vtkCellArray *newLines;
  int idx;
  vtkIdType ids[2], numPts, offset;
  // for marching through the points along an edge.
  vtkIdType start = 0, id;
  int num = 0, inc = 0;
  int edgeFlag;
  int i;

  inPts = input->GetPoints();
  if (!inPts)
  {
    return 1;
  }

  newLines = vtkCellArray::New();
  newPts = vtkPoints::New();

  ext = input->GetExtent();
  wExt = inInfo->Get(vtkStreamingDemandDrivenPipeline::WHOLE_EXTENT());

  // Since it is possible that the extent is larger than the whole extent,
  // and we want the outline to be the whole extent,
  // compute the clipped extent.
  memcpy(cExt, ext, 6*sizeof(int));
  for (i = 0; i < 3; ++i)
  {
    if (cExt[2*i] < wExt[2*i])
    {
      cExt[2*i] = wExt[2*i];
    }
    if (cExt[2*i+1] > wExt[2*i+1])
    {
      cExt[2*i+1] = wExt[2*i+1];
    }
  }

  for (i = 0; i < 12; i++ )
  {
    // Find the start of this edge, the length of this edge, and increment.
    xInc = 1;
    yInc = ext[1]-ext[0]+1;
    zInc = yInc * (ext[3]-ext[2]+1);
    edgeFlag = 0;
    switch (i)
    {
      case 0:
        // start (0, 0, 0) increment z axis.
        if (cExt[0] <= wExt[0] && cExt[2] <= wExt[2])
        {
          edgeFlag = 1;
        }
        num = cExt[5]-cExt[4]+1;
        start = (cExt[0]-ext[0])*xInc + (cExt[2]-ext[2])*yInc + (cExt[4]-ext[4])*zInc;
        inc = zInc;
      break;
      case 1:
        // start (xMax, 0, 0) increment z axis.
        if (cExt[1] >= wExt[1] && cExt[2] <= wExt[2])
        {
          edgeFlag = 1;
        }
        num = cExt[5]-cExt[4]+1;
        start = (cExt[1]-ext[0])*xInc + (cExt[2]-ext[2])*yInc + (cExt[4]-ext[4])*zInc;
        inc = zInc;
        break;
      case 2:
        // start (0, yMax, 0) increment z axis.
        if (cExt[0] <= wExt[0] && cExt[3] >= wExt[3])
        {
          edgeFlag = 1;
        }
        num = cExt[5]-cExt[4]+1;
        start = (cExt[0]-ext[0])*xInc + (cExt[3]-ext[2])*yInc + (cExt[4]-ext[4])*zInc;
        inc = zInc;
        break;
      case 3:
        // start (xMax, yMax, 0) increment z axis.
        if (cExt[1] >= wExt[1] && cExt[3] >= wExt[3])
        {
          edgeFlag = 1;
        }
        num = cExt[5]-cExt[4]+1;
        start = (cExt[1]-ext[0])*xInc + (cExt[3]-ext[2])*yInc + (cExt[4]-ext[4])*zInc;
        inc = zInc;
        break;
      case 4:
        // start (0, 0, 0) increment y axis.
        if (cExt[0] <= wExt[0] && cExt[4] <= wExt[4])
        {
          edgeFlag = 1;
        }
        num = cExt[3]-cExt[2]+1;
        start = (cExt[0]-ext[0])*xInc + (cExt[2]-ext[2])*yInc + (cExt[4]-ext[4])*zInc;
        inc = yInc;
        break;
      case 5:
        // start (xMax, 0, 0) increment y axis.
        if (cExt[1] >= wExt[1] && cExt[4] <= wExt[4])
        {
          edgeFlag = 1;
        }
        num = cExt[3]-cExt[2]+1;
        start = (cExt[1]-ext[0])*xInc + (cExt[2]-ext[2])*yInc + (cExt[4]-ext[4])*zInc;
        inc = yInc;
        break;
      case 6:
        // start (0, 0, zMax) increment y axis.
        if (cExt[0] <= wExt[0] && cExt[5] >= wExt[5])
        {
          edgeFlag = 1;
        }
        num = cExt[3]-cExt[2]+1;
        start = (cExt[0]-ext[0])*xInc + (cExt[2]-ext[2])*yInc + (cExt[5]-ext[4])*zInc;
        inc = yInc;
        break;
      case 7:
        // start (xMax, 0, zMax) increment y axis.
        if (cExt[1] >= wExt[1] && cExt[5] >= wExt[5])
        {
          edgeFlag = 1;
        }
        num = cExt[3]-cExt[2]+1;
        start = (cExt[1]-ext[0])*xInc + (cExt[2]-ext[2])*yInc + (cExt[5]-ext[4])*zInc;
        inc = yInc;
        break;
      case 8:
        // start (0, 0, 0) increment x axis.
        if (cExt[2] <= wExt[2] && cExt[4] <= wExt[4])
        {
          edgeFlag = 1;
        }
        num = cExt[1]-cExt[0]+1;
        start = (cExt[0]-ext[0])*xInc + (cExt[2]-ext[2])*yInc + (cExt[4]-ext[4])*zInc;
        inc = xInc;
        break;
      case 9:
        // start (0, yMax, 0) increment x axis.
        if (cExt[3] >= wExt[3] && cExt[4] <= wExt[4])
        {
          edgeFlag = 1;
        }
        num = cExt[1]-cExt[0]+1;
        start = (cExt[0]-ext[0])*xInc + (cExt[3]-ext[2])*yInc + (cExt[4]-ext[4])*zInc;
        inc = xInc;
        break;
      case 10:
        // start (0, 0, zMax) increment x axis.
        if (cExt[2] <= wExt[2] && cExt[5] >= wExt[5])
        {
          edgeFlag = 1;
        }
        num = cExt[1]-cExt[0]+1;
        start = (cExt[0]-ext[0])*xInc + (cExt[2]-ext[2])*yInc + (cExt[5]-ext[4])*zInc;
        inc = xInc;
        break;
      case 11:
        // start (0, yMax, zMax) increment x axis.
        if (cExt[3] >= wExt[3] && cExt[5] >= wExt[5])
        {
          edgeFlag = 1;
        }
        num = cExt[1]-cExt[0]+1;
        start = (cExt[0]-ext[0])*xInc + (cExt[3]-ext[2])*yInc + (cExt[5]-ext[4])*zInc;
        inc = xInc;
        break;
    }

    if (edgeFlag && num > 1)
    {
      offset = newPts->GetNumberOfPoints();
      numPts = inPts->GetNumberOfPoints();

      // add points
      for (idx = 0; idx < num; ++idx)
      {
        id = start + idx * inc;
        // sanity check
        if (id < 0 || id >= numPts)
        {
          vtkErrorMacro("Error stepping through points.");
          return 0;
        }
        newPts->InsertNextPoint(inPts->GetPoint(id));
      }

      // add lines
      for (idx = 1; idx < num; ++idx)
      {
        ids[0] = idx+offset-1;
        ids[1] = idx+offset;
        newLines->InsertNextCell(2, ids);
      }
    }
  }

  output->SetPoints(newPts);
  newPts->Delete();
  output->SetLines(newLines);
  newLines->Delete();

  return 1;
}

int vtkStructuredGridOutlineFilter::FillInputPortInformation(
  int, vtkInformation *info)
{
  info->Set(vtkAlgorithm::INPUT_REQUIRED_DATA_TYPE(), "vtkStructuredGrid");
  return 1;
}

