/*=========================================================================
 *
 *  Copyright NumFOCUS
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *         https://www.apache.org/licenses/LICENSE-2.0.txt
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *=========================================================================*/
#ifndef itkSimplexMesh_h
#define itkSimplexMesh_h

#include "itkMesh.h"
#include "itkSimplexMeshGeometry.h"
#include "itkVertexCell.h"
#include "itkTriangleCell.h"
#include "itkFixedArray.h"
#include <vector>
#include <algorithm>
#include <set>

namespace itk
{
/** \class SimplexMesh
 * \brief The class represents a 2-simplex mesh.
 *
 * A simplex mesh can be used for deformable model segmentation of 3D image data.
 * To create a simplex mesh one needs a triangle mesh, which can be converted
 * to using the class itkTriangleMeshToSimplexMeshFilter. The back filtering
 * (from simplex to triangle mesh)is done through a itkSimplexMeshToTriangleMeshFilter.
 *
 * \author Thomas Boettger. Division Medical and Biological Informatics, German Cancer Research Center, Heidelberg.
 * \ingroup ITKMesh
 */
template <typename TPixelType,
          unsigned int VDimension = 3,
          typename TMeshTraits =
            DefaultStaticMeshTraits<TPixelType, VDimension, VDimension, TPixelType, TPixelType, TPixelType>>
class ITK_TEMPLATE_EXPORT SimplexMesh : public Mesh<TPixelType, VDimension, TMeshTraits>
{
public:
  ITK_DISALLOW_COPY_AND_MOVE(SimplexMesh);

  /** Standard type alias. */
  using Self = SimplexMesh;

  /** Standard type alias. */
  using Superclass = Mesh<TPixelType, VDimension, TMeshTraits>;

  /** Standard type alias. */
  using Pointer = SmartPointer<Self>;

  /** Standard type alias. */
  using ConstPointer = SmartPointer<const Self>;

  /** definition for array of indices. */
  using IndexArray = typename SimplexMeshGeometry::IndexArray;

  /** definition for a set of neighbor indices */
  using NeighborSetType = std::set<SizeValueType>;

  /** */
  using NeighborSetIterator = typename NeighborSetType::iterator;

  /** */
  using NeighborListType = std::vector<SizeValueType>;

  /** */
  using PointType = typename TMeshTraits::PointType;

  /** */
  using PointIdentifier = typename TMeshTraits::PointIdentifier;

  /** */
  using VectorType = typename PointType::VectorType;

  /** */
  using CovariantVectorType = CovariantVector<typename VectorType::ValueType, 3>;

  /** */
  using typename Superclass::CellType;

  /** */
  using CellAutoPointer = typename CellType::CellAutoPointer;
  /** */
  using LineType = itk::LineCell<CellType>;

  /** map containing a SimplexMeshGeometry data object for each mesh
   * point */
  using GeometryMapType = itk::MapContainer<SizeValueType, SimplexMeshGeometry *>;

  /** smartpointer def for the geometry map */
  using GeometryMapPointer = typename GeometryMapType::Pointer;

  /** iterator definition for iterating over a geometry map */
  using GeometryMapIterator = typename GeometryMapType::Iterator;
  using GeometryMapConstIterator = typename GeometryMapType::ConstIterator;

  // Backward compatibility to expose enum from class.
  using MeshClassCellsAllocationMethodEnum = itk::MeshEnums::MeshClassCellsAllocationMethod;

  /** Method for creation through the object factory. */
  itkNewMacro(Self);

  /** \see LightObject::GetNameOfClass() */
  itkOverrideGetNameOfClassMacro(SimplexMesh);

  /** Hold on to the type information specified by the template parameters. */
  using MeshTraits = TMeshTraits;
  using PixelType = typename MeshTraits::PixelType;
  using PointsContainer = typename MeshTraits::PointsContainer;
  using typename Superclass::PointsContainerPointer;
  using PointsContainerIterator = typename Superclass::PointsContainer::Iterator;
  using typename Superclass::PointsContainerConstIterator;
  using typename Superclass::CellsContainerPointer;
  using typename Superclass::CellsContainerConstPointer;
  using typename Superclass::CellsContainerIterator;
  using typename Superclass::CellsContainerConstIterator;
  using typename Superclass::CellIdentifier;

  /** set the map of geometrydata to the new pointer */
  itkSetMacro(GeometryData, GeometryMapPointer);

  /** returns the current map of geometrydata */
  itkGetConstReferenceMacro(GeometryData, GeometryMapPointer);

  /** Get the first free id for new cells */
  itkSetMacro(LastCellId, CellIdentifier);

  /** Set the id value valid for new cells */
  itkGetConstMacro(LastCellId, CellIdentifier);

  /**
   * copy all necessary information from passed object
   * to the mesh
   */
  void
  CopyInformation(const DataObject * data) override;

  /**
   * Add a new edge to the simplex mesh by specifying the ids of the start
   * and end point of the edge
   * Note: This can destroy the simplex mesh structure! Better use the
   * simplex mesh modification or creation filters
   */
  CellIdentifier
  AddEdge(PointIdentifier startPointId, PointIdentifier endPointId);

  /**
   * Add a new simplex mesh cell to the mesh by passing an AutoPointer of a
   * previously created simplex mesh cell
   *
   * Note: This can destroy the simplex mesh structure! You should use the
   * simplex mesh modification or creation filters.
   */
  CellIdentifier
  AddFace(CellAutoPointer & cellPointer);

  /**
   * Replaces the cell specified by replaceIndex with the new cell passed by its
   * AutoPointer
   */
  CellIdentifier
  ReplaceFace(CellIdentifier replaceIndex, CellAutoPointer & cellPointer);

  /**
   * Get the three direct neighbors of a point
   */
  IndexArray
  GetNeighbors(PointIdentifier idx) const;

  /**
   * Get all neighbor points with a specified radius
   */
  NeighborListType *
  GetNeighbors(PointIdentifier idx, unsigned int radius, NeighborListType * list = nullptr) const;

  /**
   * Add a neighbor to a point.
   * Note: This can destroy the simplex mesh topology!
   * Better use the simplex mesh creation filters.
   */
  void
  AddNeighbor(PointIdentifier pointIdx, PointIdentifier neighborIdx);

  /**
   * Replace a neighbor of a specific point by a new one
   */
  void
  ReplaceNeighbor(PointIdentifier pointIdx, PointIdentifier oldIdx, PointIdentifier newIdx);

  /**
   * Swap the order of two neighbors
   */
  void
  SwapNeighbors(PointIdentifier pointIdx, PointIdentifier firstIdx, PointIdentifier secondIdx);

  /**
   * Set the geometry data for a specified point
   */
  void
  SetGeometryData(PointIdentifier pointId, SimplexMeshGeometry *);

  /**
   * Set the geometry data for a specified point
   */
  void
  SetBarycentricCoordinates(PointIdentifier idx, PointType value);

  /**
   * Set the barycentric coordinates for a specified point
   */
  PointType
  GetBarycentricCoordinates(PointIdentifier idx) const;

  /**
   * Set the reference metrics for a specified point
   */
  void
  SetReferenceMetrics(PointIdentifier idx, PointType value);

  /**
   *  Return the reference metrics for the specified point
   */
  PointType
  GetReferenceMetrics(PointIdentifier idx) const;

  /**
   * Set the simplex angle for the specified point
   */
  void
  SetPhi(PointIdentifier idx, double value);

  /**
   * Get the simplex angle for the specified point
   */
  double
  GetPhi(PointIdentifier idx) const;

  /**
   * Set the mean curvature for the specified point
   */
  void
  SetMeanCurvature(PointIdentifier idx, double value);

  /**
   * Get the mean curvature for the specified point
   */
  double
  GetMeanCurvature(PointIdentifier idx) const;

  /**
   * Set the circum circles radius for the specified point
   */
  void
  SetRadius(PointIdentifier idx, double value);

  /**
   * Get the circum circles radius for the specified point
   */
  double
  GetRadius(PointIdentifier idx) const;

  /**
   * Set the distance to the foot point for the specified point
   */
  void
  SetDistance(PointIdentifier idx, double value);

  /**
   * Get the distance to the foot point for the specified point
   */
  double
  GetDistance(PointIdentifier idx) const;

  /** compute the normal vector in the specified mesh point */
  CovariantVectorType
  ComputeNormal(PointIdentifier idx) const;

protected:
  //  /** Constructor for use by New() method. */
  SimplexMesh();
  ~SimplexMesh() override;
  void
  PrintSelf(std::ostream & os, Indent indent) const override;

  /**
   * The map stores a SimplexMeshGeometry object for each mesh point
   */
  GeometryMapPointer m_GeometryData{};

  /**
   * The last cell id is the index which is used for insertion of new
   * cells. It increases during mesh creation. This is done because
   * one cannot rely on the size of the map or the highest index when
   * cells are removed.
   */
  CellIdentifier m_LastCellId{};
}; // End Class:  SimplexMesh
} // end namespace itk

#ifndef ITK_MANUAL_INSTANTIATION
#  include "itkSimplexMesh.hxx"
#endif

#endif