//=========================================================================
//  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.
//=========================================================================

#include "vtkDiscreteModelEdge.h"

#include "vtkCell.h"
#include "vtkIdList.h"
#include "vtkIdTypeArray.h"
#include "vtkModelEdgeUse.h"
#include "vtkModelFace.h"
#include "vtkModelItemIterator.h"
#include "vtkModelVertexUse.h"
#include "vtkObjectFactory.h"

#include "vtkDiscreteModel.h"
#include "vtkDiscreteModelRegion.h"
#include "vtkDiscreteModelVertex.h"
#include "vtkInformation.h"
#include "vtkInformationDoubleVectorKey.h"
#include "vtkInformationIntegerKey.h"
#include "vtkInformationObjectBaseKey.h"
#include "vtkLineSource.h"
#include "vtkNew.h"
#include "vtkProperty.h"
#include "vtkSmartPointer.h"
#include "vtkSplitEventData.h"

vtkInformationKeyMacro(vtkDiscreteModelEdge, LINERESOLUTION, Integer);
vtkInformationKeyMacro(vtkDiscreteModelEdge, LINEADNPOINTSGEOMETRY, ObjectBase);

vtkDiscreteModelEdge* vtkDiscreteModelEdge::New()
{
  vtkObject* ret = vtkObjectFactory::CreateInstance("vtkDiscreteModelEdge");
  if (ret)
  {
    return static_cast<vtkDiscreteModelEdge*>(ret);
  }
  return new vtkDiscreteModelEdge;
}

vtkDiscreteModelEdge::vtkDiscreteModelEdge()
{
  this->GetProperties()->Set(LINERESOLUTION(), 1);
  vtkProperty* displayProp = this->GetDisplayProperty();
  displayProp->SetLineWidth(2.0);
  displayProp->SetPointSize(6.0);
}

vtkDiscreteModelEdge::~vtkDiscreteModelEdge()
{
}

bool vtkDiscreteModelEdge::IsDestroyable()
{
  vtkModelItemIterator* edgeUseIter = this->NewModelEdgeUseIterator();
  for (edgeUseIter->Begin(); !edgeUseIter->IsAtEnd(); edgeUseIter->Next())
  {
    if (vtkModelEdgeUse::SafeDownCast(edgeUseIter->GetCurrentItem())->GetModelLoopUse())
    {
      edgeUseIter->Delete();
      return false;
    }
  }
  edgeUseIter->Delete();
  return true;
}

bool vtkDiscreteModelEdge::Destroy()
{
  this->GetModel()->InvokeModelGeometricEntityEvent(ModelGeometricEntityAboutToDestroy, this);
  vtkModelItemIterator* EdgeUseIter = this->NewModelEdgeUseIterator();
  for (EdgeUseIter->Begin(); !EdgeUseIter->IsAtEnd(); EdgeUseIter->Next())
  {
    if (!vtkModelEdgeUse::SafeDownCast(EdgeUseIter->GetCurrentItem())->Destroy())
    {
      vtkErrorMacro("Problem destroying edge use of an edge.");
      this->Modified();
      EdgeUseIter->Delete();
      return false;
    }
  }
  EdgeUseIter->Delete();
  this->RemoveAllAssociations(vtkModelEdgeUseType);
  // For the floating edge, we have associations with regions
  this->RemoveAllAssociations(vtkModelRegionType);
  this->RemoveAllAssociations(vtkDiscreteModelEntityGroupType);
  this->Modified();
  return true;
}

vtkModelEntity* vtkDiscreteModelEdge::GetThisModelEntity()
{
  return this;
}

void vtkDiscreteModelEdge::AddRegionAssociation(vtkIdType regionId)
{
  vtkDiscreteModelRegion* region = vtkDiscreteModelRegion::SafeDownCast(
    this->GetModel()->GetModelEntity(vtkModelRegionType, regionId));
  if (region)
  {
    this->AddAssociation(region);
    this->GetModel()->InvokeModelGeometricEntityEvent(ModelGeometricEntityBoundaryModified, region);
  }
}

vtkObject* vtkDiscreteModelEdge::GetGeometry()
{
  if (vtkObject* object = this->Superclass::GetGeometry())
  {
    return object;
  }
  if (this->GetNumberOfAssociations(vtkModelRegionType))
  {
    vtkDiscreteModel* model = vtkDiscreteModel::SafeDownCast(this->GetModel());
    if (model->HasValidMesh())
    { // only construct the representation if it is a floating edge on the server
      this->ConstructRepresentation();
      return this->Superclass::GetGeometry();
    }
  }
  return 0;
}

bool vtkDiscreteModelEdge::ConstructRepresentation()
{
  if (this->GetGeometry())
  {
    return 1;
  }
  vtkModelVertex* vertex1 = this->GetAdjacentModelVertex(0);
  vtkModelVertex* vertex2 = this->GetAdjacentModelVertex(1);
  if (!vertex1 || !vertex2)
  {
    vtkWarningMacro("Cannot construct model edge representation without model vertices.");
    return false;
  }
  vtkSmartPointer<vtkLineSource> lineSource = vtkSmartPointer<vtkLineSource>::New();
  double xyz[3];
  if (vertex1->GetPoint(xyz))
  {
    lineSource->SetPoint1(xyz);
  }
  else
  {
    vtkErrorMacro("Model vertex does not have a point set yet.");
  }
  if (vertex2->GetPoint(xyz))
  {
    lineSource->SetPoint2(xyz);
  }
  else
  {
    vtkErrorMacro("Model vertex does not have a point set yet.");
  }
  lineSource->SetResolution(this->GetLineResolution());
  lineSource->Update();

  vtkPolyData* poly = vtkPolyData::New();
  poly->DeepCopy(lineSource->GetOutputDataObject(0));
  this->SetGeometry(poly);

  poly->Delete();
  return true;
}

bool vtkDiscreteModelEdge::Split(
  vtkIdType splitPointId, vtkIdType& createdVertexId, vtkIdType& createdEdgeId)
{
  vtkObject* geometry = this->GetGeometry();
  vtkPolyData* poly = vtkPolyData::SafeDownCast(geometry);

  if (poly == 0 || poly->GetNumberOfCells() == 0)
  {
    if (geometry)
    {
      // we are on the server...
      return 0;
    }
    // BoundaryRep has not been set -> return error
    return 0;
  }
  if (splitPointId >= poly->GetNumberOfPoints() || splitPointId < 0)
  {
    vtkErrorMacro("Bad point id for model edge split.");
    return 0;
  }

  // on server, go ahead and perform the split first determine if
  // it is a loop with no starting or ending point because if it
  // is splitting won't create a new model edge, it will just
  // modify the current model edge

  if (this->GetAdjacentModelVertex(0) == 0)
  {
    createdEdgeId = -1;
    createdVertexId = -1;
    if (this->SplitModelEdgeLoop(splitPointId) == false)
    {
      vtkErrorMacro("Unable to split edge loop.");
      return 0;
    }
    vtkModelVertex* newVertex = this->GetAdjacentModelVertex(0);
    createdVertexId = newVertex->GetUniquePersistentId();
    vtkIdList* createdEntityIds = vtkIdList::New();
    createdEntityIds->InsertNextId(createdVertexId);
    vtkSplitEventData* splitEventData = vtkSplitEventData::New();
    splitEventData->SetSourceEntity(this);
    splitEventData->SetCreatedModelEntityIds(createdEntityIds);
    createdEntityIds->Delete();
    this->GetModel()->InvokeModelGeometricEntityEvent(ModelGeometricEntitySplit, splitEventData);
    splitEventData->Delete();
    return true;
  }

  vtkIdType modelEdgeStartPoint =
    vtkDiscreteModelVertex::SafeDownCast(this->GetAdjacentModelVertex(0))->GetPointId();
  vtkIdType modelEdgeEndPoint =
    vtkDiscreteModelVertex::SafeDownCast(this->GetAdjacentModelVertex(1))->GetPointId();
  if (splitPointId == modelEdgeStartPoint || splitPointId == modelEdgeEndPoint)
  {
    vtkWarningMacro("Picked an end point for splitting a model edge.");
    return 0;
  }

  poly->BuildLinks();
  // if a model vertex already exists at splitPointId we don't need to split
  vtkSmartPointer<vtkIdList> pointCells = vtkSmartPointer<vtkIdList>::New();
  poly->GetPointCells(modelEdgeEndPoint, pointCells);
  if (pointCells->GetNumberOfIds() != 1 &&
    (pointCells->GetNumberOfIds() != 2 && modelEdgeStartPoint == modelEdgeEndPoint))
  {
    vtkWarningMacro("Improper grid.");
    return 0;
  }
  poly->GetPointCells(splitPointId, pointCells);
  if (pointCells->GetNumberOfIds() < 2)
  {
    vtkWarningMacro("Improper splitting point for splitting an edge.");
    poly->DeleteLinks();
    return 0;
  }

  // we do a cell walk from the split point to the end the edge polydata
  // and those are the cells that get assigned to the new model edge
  vtkSmartPointer<vtkIdList> newModelEdgeCells = vtkSmartPointer<vtkIdList>::New();
  vtkSmartPointer<vtkIdList> currentPtIds = vtkSmartPointer<vtkIdList>::New();

  /*
  * Before we start walking the edges to go from the split 
  * point to the end point we first need to determine the
  * cell to start at. 
  * 
  *    p1 ----c1---- p2 ----- c2 ----- p3
  *
  * If we consider the split point is p2 and the end point is p3,
  * we need to determine if we should start walking at c1 or c2. 
  * Do do this we look at all the cells that use p2, and select
  * the cell that uses p2 as the first point id (this does presume
  * all cells are ordered head to tail ). 
  * 
  */

  vtkIdType currentCellId = -1;
  for (int i = 0; i < pointCells->GetNumberOfIds(); ++i)
  {
    poly->GetCellPoints(pointCells->GetId(i), currentPtIds);
    if (splitPointId == currentPtIds->GetId(0))
    {
      currentCellId = pointCells->GetId(i);
      break;
    }
  }

  if (currentCellId < 0)
  {
    vtkWarningMacro("Could not find a proper line cell to start splitting edge.");
    poly->DeleteLinks();
    return false;
  }

  /*
  * Now start the walk from the cell that uses the split
  * point as its first point Id, intill we find a cell
  * that uses the end point 
  *
  * The logic is:
  * Start at a given cell
  * Find the points of said cell. ( label start )
  * Find the first point used by the cell that isn't our
  *   marked point ( currentPointId )
  * For this point find the first cell that isn't our self
  * Loop back to label start
  * 
  */

  newModelEdgeCells->InsertNextId(currentCellId);
  vtkIdType currentPointId = splitPointId;
  while (currentCellId >= 0)
  {
    vtkIdType nextCellId = -1;
    poly->GetCellPoints(currentCellId, currentPtIds);

    for (int i = 0; i < 2 && nextCellId == -1; i++)
    {
      if (currentPtIds->GetId(i) != currentPointId)
      {
        poly->GetPointCells(currentPtIds->GetId(i), pointCells);
        if (currentPtIds->GetId(i) == modelEdgeEndPoint)
        {
          nextCellId = -2; // stop condition
        }
        else
        {
          for (int j = 0; j < 2 && nextCellId == -1; j++)
          {
            if (pointCells->GetId(j) != currentCellId)
            {
              nextCellId = pointCells->GetId(j);
              newModelEdgeCells->InsertNextId(nextCellId);
              currentPointId = currentPtIds->GetId(i);
            }
          }
          if (nextCellId < 0)
          {
            vtkWarningMacro("Could not perform grid walk.");
            return 0;
          }
        }
      }
    }
    currentCellId = nextCellId;
  }

  //Now we convert from local id space to global id space
  {
    const vtkIdType size = newModelEdgeCells->GetNumberOfIds();
    for (vtkIdType s = 0; s < size; ++s)
    {
      const vtkIdType mc = this->GetMasterCellId(newModelEdgeCells->GetId(s));
      newModelEdgeCells->SetId(s, mc);
    }
  }

  // we could save this for later use but for now assume we should
  // delete to save memory
  poly->DeleteLinks();
  if (newModelEdgeCells->GetNumberOfIds() >= poly->GetNumberOfCells())
  {
    vtkErrorMacro("Bad list of cells to split off from existing model edge.");
    return 0;
  }
  vtkDiscreteModel* model = vtkDiscreteModel::SafeDownCast(this->GetModel());
  vtkModelVertex* vertex = model->BuildModelVertex(splitPointId);
  createdVertexId = vertex->GetUniquePersistentId();
  bool blockEvent = this->GetModel()->GetBlockModelGeometricEntityEvent();
  this->GetModel()->SetBlockModelGeometricEntityEvent(1);
  vtkDiscreteModelEdge* newEdge = vtkDiscreteModelEdge::SafeDownCast(model->BuildModelEdge(0, 0));
  this->GetModel()->SetBlockModelGeometricEntityEvent(blockEvent);
  this->Superclass::SplitModelEdge(vertex, newEdge);
  // now create the poly data for the new edge
  newEdge->AddCellsToGeometry(newModelEdgeCells);
  createdEdgeId = newEdge->GetUniquePersistentId();
  this->GetModel()->InvokeModelGeometricEntityEvent(ModelGeometricEntityCreated, newEdge);
  this->GetModel()->InvokeModelGeometricEntityEvent(ModelGeometricEntityBoundaryModified, this);

  vtkIdList* createdEntityIds = vtkIdList::New();
  createdEntityIds->InsertNextId(createdVertexId);
  createdEntityIds->InsertNextId(createdEdgeId);
  vtkSplitEventData* splitEventData = vtkSplitEventData::New();
  splitEventData->SetSourceEntity(this);
  splitEventData->SetCreatedModelEntityIds(createdEntityIds);
  createdEntityIds->Delete();
  this->GetModel()->InvokeModelGeometricEntityEvent(ModelGeometricEntitySplit, splitEventData);
  splitEventData->Delete();

  vtkModelItemIterator* faces = newEdge->NewAdjacentModelFaceIterator();
  for (faces->Begin(); !faces->IsAtEnd(); faces->Next())
  {
    vtkModelFace* face = vtkModelFace::SafeDownCast(faces->GetCurrentItem());
    face->GetModel()->InvokeModelGeometricEntityEvent(ModelGeometricEntityBoundaryModified, face);
  }
  faces->Delete();
  vtkDiscreteModelVertex* ModelVertex = vtkDiscreteModelVertex::SafeDownCast(vertex);
  if (ModelVertex)
  {
    ModelVertex->CreateGeometry();
  }
  return 1;
}

bool vtkDiscreteModelEdge::SplitModelEdgeLoop(vtkIdType pointId)
{
  vtkDiscreteModel* model = vtkDiscreteModel::SafeDownCast(this->GetModel());
  vtkModelVertex* vertex = model->BuildModelVertex(pointId);
  bool result = this->Superclass::SplitModelEdgeLoop(vertex);
  if (result)
  {
    vtkDiscreteModelVertex* ModelVertex = vtkDiscreteModelVertex::SafeDownCast(vertex);
    if (ModelVertex)
    {
      ModelVertex->CreateGeometry();
    }
  }
  return result;
}

void vtkDiscreteModelEdge::SetLineResolution(int lineResolution)
{
  if (lineResolution > 0 && lineResolution != this->GetLineResolution())
  {
    this->GetProperties()->Set(LINERESOLUTION(), lineResolution);
    // this->UpdateGeometry();
    this->Modified();
  }
}

int vtkDiscreteModelEdge::GetLineResolution()
{
  return this->GetProperties()->Get(LINERESOLUTION());
}

void vtkDiscreteModelEdge::SetLineAndPointsGeometry(vtkObject* geometry)
{
  this->GetProperties()->Set(LINEADNPOINTSGEOMETRY(), geometry);
  this->Modified();
}

vtkObject* vtkDiscreteModelEdge::GetLineAndPointsGeometry()
{
  vtkObject* object = vtkObject::SafeDownCast(this->GetProperties()->Get(LINEADNPOINTSGEOMETRY()));
  return object;
}

void vtkDiscreteModelEdge::Serialize(vtkSerializer* ser)
{
  this->Superclass::Serialize(ser);
}

vtkModelRegion* vtkDiscreteModelEdge::GetModelRegion()
{
  vtkModelItemIterator* iter = this->NewIterator(vtkModelRegionType);
  iter->Begin();
  vtkModelRegion* region = vtkModelRegion::SafeDownCast(iter->GetCurrentItem());
  iter->Delete();
  return region;
}
void vtkDiscreteModelEdge::GetAllPointIds(vtkIdList* ptsList)
{
  ptsList->Reset();
  vtkPolyData* edgePoly = vtkPolyData::SafeDownCast(this->GetGeometry());
  if (edgePoly == NULL)
  { // we're on the client and don't know this info
    return;
  }
  //ptsList->SetNumberOfIds(edgePoly->GetNumberOfPoints());
  vtkNew<vtkIdList> cellPtsIds;
  for (vtkIdType i = 0; i < edgePoly->GetNumberOfCells(); i++)
  {
    edgePoly->GetCellPoints(i, cellPtsIds.GetPointer());
    if (cellPtsIds->GetNumberOfIds() != 2)
    {
      vtkErrorMacro("Bad cell type.");
      return;
    }
    ptsList->InsertUniqueId(cellPtsIds->GetId(0));
    ptsList->InsertUniqueId(cellPtsIds->GetId(1));
  }
  //ptsList->Squeeze();
}
void vtkDiscreteModelEdge::GetInteriorPointIds(vtkIdList* ptsList)
{
  vtkNew<vtkIdList> boundaryPtsList;
  this->GetAllPointIds(ptsList);
  this->GetBoundaryPointIds(boundaryPtsList.GetPointer());
  for (vtkIdType i = 0; i < boundaryPtsList->GetNumberOfIds(); i++)
  {
    ptsList->DeleteId(boundaryPtsList->GetId(i));
  }
}
void vtkDiscreteModelEdge::GetBoundaryPointIds(vtkIdList* ptsList)
{
  ptsList->Reset();
  vtkPolyData* edgePoly = vtkPolyData::SafeDownCast(this->GetGeometry());
  if (edgePoly == NULL)
  { // we're on the client and don't know this info
    return;
  }
  for (int i = 0; i < 2; i++)
  {
    vtkDiscreteModelVertex* modelVertex =
      vtkDiscreteModelVertex::SafeDownCast(this->GetAdjacentModelVertex(i));
    if (modelVertex)
    {
      ptsList->InsertUniqueId(modelVertex->GetPointId());
    }
  }
}

bool vtkDiscreteModelEdge::AddCellsToGeometry(vtkIdList* masterCellIds)
{
  const vtkIdType numCells = masterCellIds->GetNumberOfIds();
  vtkIdType* cellids = masterCellIds->GetPointer(0);

  //only transform the ids if they are already positive
  //otherwise we are doing something like a split and we already have
  //have ids in edge index space
  bool idsModified = false;
  if (numCells > 0 && cellids[0] >= 0)
  {
    DiscreteMesh::FlatIdSpaceToEdgeIdSpace(cellids, numCells);
    idsModified = true;
  }

  bool retVal = vtkDiscreteModelGeometricEntity::AddCellsToGeometry(masterCellIds);

  if (idsModified)
  { // transform the ids back
    DiscreteMesh::EdgeIdSpaceToFlatIdSpace(cellids, numCells);
  }
  return retVal;
}

bool vtkDiscreteModelEdge::AddCellsClassificationToMesh(vtkIdList* cellids)
{
  // now add cells on this entity
  vtkModelGeometricEntity* thisEntity =
    vtkModelGeometricEntity::SafeDownCast(this->GetThisModelEntity());
  vtkDiscreteModel* model = vtkDiscreteModel::SafeDownCast(thisEntity->GetModel());

  vtkPolyData* entityPoly = vtkPolyData::SafeDownCast(thisEntity->GetGeometry());

  const DiscreteMesh& mesh = model->GetMesh();
  vtkDiscreteModel::ClassificationType& classification = model->GetMeshClassification();

  vtkNew<vtkIdList> pointIds;
  vtkIdType nextPId = -1, numCells = cellids->GetNumberOfIds();
  vtkIdType nextCellId;
  // We can not be sure which is the first cell of the edge so we need to find it
  // The first cell will  not have its first point id be refered in any other cell's last pid
  // unless it is a circular loop  and in that case it doesn't matter
  std::set<vtkIdType> endPIDS;
  vtkIdType i;
  for (i = 0; i < numCells; i++)
  {
    nextCellId = cellids->GetId(i);
    mesh.GetCellPointIds(nextCellId, pointIds.GetPointer());
    endPIDS.insert(pointIds->GetId(pointIds->GetNumberOfIds() - 1));
  }
  for (i = 0; i < numCells; i++)
  {
    nextCellId = cellids->GetId(i);
    mesh.GetCellPointIds(nextCellId, pointIds.GetPointer());
    if (endPIDS.find(pointIds->GetId(0)) == endPIDS.end())
    {
      // We found the starting cell!
      break;
    }
  }
  // Did we fund a loop edge?  (i.e. we did not find a PID that was not included in two different cells)
  if (i == numCells)
  {
    nextCellId = cellids->GetId(0);
  }
  for (i = 0; i < numCells; i++)
  {
    // Is this the first cell being inserted?
    if (!i)
    {
      mesh.GetCellPointIds(nextCellId, pointIds.GetPointer());
    }
    else
    {
      // Need to find the next cell along the edge - assuming most of the time the cells are
      // already sorted we will initial start at the next available ID
      vtkIdType j, k;
      bool found;
      for (found = false, j = (i + 1) % numCells, k = 0; !found && (k < numCells);
           j = (j + 1) % numCells, k++)
      {
        nextCellId = cellids->GetId(j);
        mesh.GetCellPointIds(nextCellId, pointIds.GetPointer());
        if (pointIds->GetId(0) == nextPId)
        {
          found = true;
        }
      }
      if (!found)
      {
        std::cerr << "\tERROR!!!  Edge is not continuous!!\n";
      }
    }
    const vtkIdType cellType = mesh.GetCellType(nextCellId);
    const vtkIdType newLocalCellId = entityPoly->InsertNextCell(cellType, pointIds.GetPointer());
    this->GetReverseClassificationArray()->InsertNextTypedTuple(&nextCellId);

    // update the classification on the model to this info
    classification.SetEntity(nextCellId, newLocalCellId, this);
    nextPId = pointIds->GetId(pointIds->GetNumberOfIds() - 1);
  }

  if (cellids->GetNumberOfIds())
  {
    entityPoly->Modified();
  }

  return true;
}

bool vtkDiscreteModelEdge::IsEdgeCellPoint(vtkIdType pointId)
{
  vtkPolyData* edgePoly = vtkPolyData::SafeDownCast(this->GetGeometry());
  if (edgePoly == NULL)
  { // we're on the client and don't know this info
    return false;
  }
  vtkSmartPointer<vtkIdList> pointCells = vtkSmartPointer<vtkIdList>::New();
  edgePoly->GetPointCells(pointId, pointCells);
  return (pointCells->GetNumberOfIds() != 0);
}

void vtkDiscreteModelEdge::PrintSelf(ostream& os, vtkIndent indent)
{
  this->Superclass::PrintSelf(os, indent);
}
