//============================================================================
//  Copyright (c) Kitware, Inc.
//  All rights reserved.
//  See LICENSE.txt 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.
//============================================================================
// Copyright (c) 2018, The Regents of the University of California, through
// Lawrence Berkeley National Laboratory (subject to receipt of any required approvals
// from the U.S. Dept. of Energy).  All rights reserved.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
// (1) Redistributions of source code must retain the above copyright notice, this
//     list of conditions and the following disclaimer.
//
// (2) Redistributions in binary form must reproduce the above copyright notice,
//     this list of conditions and the following disclaimer in the documentation
//     and/or other materials provided with the distribution.
//
// (3) Neither the name of the University of California, Lawrence Berkeley National
//     Laboratory, U.S. Dept. of Energy nor the names of its contributors may be
//     used to endorse or promote products derived from this software without
//     specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
// ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
// WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
// IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
// INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
// BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
// OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
// OF THE POSSIBILITY OF SUCH DAMAGE.
//
//=============================================================================
//
//  This code is an extension of the algorithm presented in the paper:
//  Parallel Peak Pruning for Scalable SMP Contour Tree Computation.
//  Hamish Carr, Gunther Weber, Christopher Sewell, and James Ahrens.
//  Proceedings of the IEEE Symposium on Large Data Analysis and Visualization
//  (LDAV), October 2016, Baltimore, Maryland.
//
//  The PPP2 algorithm and software were jointly developed by
//  Hamish Carr (University of Leeds), Gunther H. Weber (LBNL), and
//  Oliver Ruebel (LBNL)
//==============================================================================

#ifndef vtkm_worklet_contourtree_augmented_active_graph_initialize_neighbourhood_masks_and_out_degrees_h
#define vtkm_worklet_contourtree_augmented_active_graph_initialize_neighbourhood_masks_and_out_degrees_h

#include <vtkm/worklet/WorkletMapField.h>

namespace vtkm
{
namespace worklet
{
namespace contourtree_augmented
{
namespace active_graph_inc
{


// Worklet for computing the sort indices from the sort order
class InitializeNeighbourhoodMasksAndOutDegrees : public vtkm::worklet::WorkletMapField
{
public:
  typedef void ControlSignature(
    FieldIn sortIndex,                // (input) sort index
    ExecObject meshStructure,         // (input) execution object with the mesh structure
    WholeArrayOut neighbourhoodMasks, // (output) neighbourhoodMask for each vertex
    WholeArrayOut outDegrees);        // (outpur) outDegress for each vertex
  typedef void ExecutionSignature(_1, InputIndex, _2, _3, _4);
  using InputDomain = _1;

  // Default Constructor
  VTKM_EXEC_CONT
  InitializeNeighbourhoodMasksAndOutDegrees()
    : isJoinGraph(true)
  {
  }

  // Constructor
  VTKM_EXEC_CONT
  InitializeNeighbourhoodMasksAndOutDegrees(const bool joinGraph)
    : isJoinGraph(joinGraph)
  {
  }

  template <typename MeshStructureType, typename OutFieldPortalType>
  VTKM_EXEC void operator()(const vtkm::Id& sortIndex,
                            const vtkm::Id vertexIndex,
                            const MeshStructureType& meshStructure,
                            const OutFieldPortalType& neighbourhoodMasksPortal,
                            const OutFieldPortalType& outDegreesPortal) const
  {
    const vtkm::Pair<vtkm::Id, vtkm::Id>& maskAndDegree =
      meshStructure.GetNeighbourComponentsMaskAndDegree(vertexIndex, isJoinGraph);
    neighbourhoodMasksPortal.Set(sortIndex, maskAndDegree.first);
    outDegreesPortal.Set(sortIndex, maskAndDegree.second);

    // In serial this worklet implements the following operation
    // for (indexType vertex = 0; vertex < mesh.sortIndices.GetNumberOfValues(); ++vertex)
    // {
    //   indexType sortIndex = mesh.sortIndices[vertex];
    //   std::tie(neighbourhoodMasks[sortIndex], outDegrees[sortIndex]) = mesh.GetNeighbourComponentsMaskAndDegree(vertex, isJoinGraph);
    // }
  }

private:
  bool isJoinGraph;

}; // Mesh2D_DEM_VertexStarter


} // namespace mesh_dem_triangulation_worklets
} // namespace contourtree_augmented
} // namespace worklet
} // namespace vtkm

#endif
