// SPDX-FileCopyrightText: Copyright (c) Ken Martin, Will Schroeder, Bill Lorensen
// SPDX-License-Identifier: BSD-3-Clause
/**
 * @class   vtkAMRUtilities
 *
 *
 *  A concrete instance of vtkObject that employs a singleton design
 *  pattern and implements functionality for AMR specific operations.
 *
 * @sa
 *  vtkOverlappingAMR, vtkAMRBox
 */

#ifndef vtkAMRUtilities_h
#define vtkAMRUtilities_h

#include "vtkCommonDataModelModule.h" // For export macro
#include "vtkObject.h"
#include <vector> // For C++ vector

// Forward declarations
VTK_ABI_NAMESPACE_BEGIN
class vtkDataArray;
class vtkFieldData;
class vtkOverlappingAMR;
class vtkUniformGrid;
class vtkUnsignedCharArray;

class VTKCOMMONDATAMODEL_EXPORT vtkAMRUtilities : public vtkObject
{
public:
  // Standard Routines
  vtkTypeMacro(vtkAMRUtilities, vtkObject);
  void PrintSelf(ostream& os, vtkIndent indent) override;

  /**
   * This method detects and strips partially overlapping cells from a
   * given AMR dataset. If ghost layers are detected, they are removed and
   * new grid instances are created to represent the stripped
   * data-set otherwise, each block is shallow-copied.

   * .SECTION Assumptions
   * 1) The ghosted AMR data must have complete metadata information.
   * 2) The ghosted AMR must contains vtkUniformGrid
   */
  static void StripGhostLayers(
    vtkOverlappingAMR* ghostedAMRData, vtkOverlappingAMR* strippedAMRData);

  /**
   * A quick test of whether partially overlapping ghost cells exist. This test
   * starts from the highest-res boxes and checks if they have partially
   * overlapping cells. The code returns with true once partially overlapping
   * cells are detected. Otherwise, false is returned.
   */
  static bool HasPartiallyOverlappingGhostCells(vtkOverlappingAMR* amr);

  /**
   * Blank cells in overlapping AMR
   */
  static void BlankCells(vtkOverlappingAMR* amr);

protected:
  vtkAMRUtilities() = default;
  ~vtkAMRUtilities() override = default;

  /**
   * Given the real-extent w.r.t. the ghosted grid, this method copies the
   * field data (point/cell) data on the stripped grid.
   */
  static void CopyFieldsWithinRealExtent(
    int realExtent[6], vtkUniformGrid* ghostedGrid, vtkUniformGrid* strippedGrid);

  /**
   * Copies the fields from the given source to the given target.
   */
  static void CopyFieldData(
    vtkFieldData* target, vtkIdType targetIdx, vtkFieldData* source, vtkIdType sourceIdx);

  /**
   * Strips ghost layers from the given grid according to the given ghost
   * vector which encodes the number of cells to remote from each of the
   * 6 sides {imin,imax,jmin,jmax,kmin,kmax}. For example, a ghost vector
   * of {0,2,0,2,0,0} would indicate that there exist 2 ghost cells on the
   * imax and jmax side.
   */
  static vtkUniformGrid* StripGhostLayersFromGrid(vtkUniformGrid* grid, int ghost[6]);

  static void BlankGridsAtLevel(vtkOverlappingAMR* amr, int levelIdx,
    std::vector<std::vector<unsigned int>>& children, const std::vector<int>& processMap);

private:
  vtkAMRUtilities(const vtkAMRUtilities&) = delete;
  void operator=(const vtkAMRUtilities&) = delete;

  static void MergeGhostArrays(vtkDataArray* existingArray, vtkUnsignedCharArray* ghosts);
};

VTK_ABI_NAMESPACE_END
#endif /* vtkAMRUtilities_h */
