// Created on: 1996-04-22
// Created by: Herve LOUESSARD
// Copyright (c) 1996-1999 Matra Datavision
// Copyright (c) 1999-2014 OPEN CASCADE SAS
//
// This file is part of Open CASCADE Technology software library.
//
// This library is free software; you can redistribute it and/or modify it under
// the terms of the GNU Lesser General Public License version 2.1 as published
// by the Free Software Foundation, with special exception defined in the file
// OCCT_LGPL_EXCEPTION.txt. Consult the file LICENSE_LGPL_21.txt included in OCCT
// distribution for complete text of the license and disclaimer of any warranty.
//
// Alternatively, this file may be used under the terms of Open CASCADE
// commercial license or contractual agreement.

// Modified: Mps(10-04-97) portage WNT

#include <BRepExtrema_DistShapeShape.hxx>

#include <Standard_OStream.hxx>
#include <TopTools_IndexedMapOfShape.hxx>
#include <BRepBndLib.hxx>
#include <Bnd_Box.hxx>
#include <TopExp.hxx>
#include <BRepExtrema_DistanceSS.hxx>
#include <TopoDS.hxx>
#include <TopoDS_Vertex.hxx>
#include <TopoDS_Edge.hxx>
#include <TopoDS_Face.hxx>
#include <TopAbs_ShapeEnum.hxx>
#include <Precision.hxx>
#include <BRepExtrema_UnCompatibleShape.hxx>
#include <BRep_Tool.hxx>
#include <BRepClass3d_SolidClassifier.hxx>
#include <NCollection_Vector.hxx>
#include <OSD_Parallel.hxx>
#include <StdFail_NotDone.hxx>

#include <algorithm>
namespace
{

  static void Decomposition(const TopoDS_Shape&         S,
                            TopTools_IndexedMapOfShape& MapV,
                            TopTools_IndexedMapOfShape& MapE,
                            TopTools_IndexedMapOfShape& MapF)
  {
    MapV.Clear();
    MapE.Clear();
    MapF.Clear();
    TopExp::MapShapes(S,TopAbs_VERTEX,MapV);
    TopExp::MapShapes(S,TopAbs_EDGE,MapE);
    TopExp::MapShapes(S,TopAbs_FACE,MapF);
  }

  static void BoxCalculation(const TopTools_IndexedMapOfShape& Map,
                             Bnd_Array1OfBox&                  SBox)
  {
    for (Standard_Integer i = 1; i <= Map.Extent(); i++)
    {
      Bnd_Box box;
      BRepBndLib::Add(Map(i), box);
      SBox[i] = box;
    }
  }

  inline Standard_Real DistanceInitiale(const TopoDS_Vertex V1,
                                        const TopoDS_Vertex V2)
  {
    return (BRep_Tool::Pnt(V1).Distance(BRep_Tool::Pnt(V2)));
  }

  //! Pair of objects to check extrema.
  struct BRepExtrema_CheckPair
  {
    Standard_Integer Index1;   //!< Index of the 1st sub-shape
    Standard_Integer Index2;   //!< Index of the 2nd sub-shape
    Standard_Real    Distance; //!< Distance between sub-shapes

    //! Uninitialized constructor for collection.
    BRepExtrema_CheckPair()
    : Index1(0),
      Index2(0),
      Distance(0.0)
    {
    }

    //! Creates new pair of sub-shapes.
    BRepExtrema_CheckPair (Standard_Integer theIndex1,
                           Standard_Integer theIndex2,
                           Standard_Real    theDistance)
    : Index1   (theIndex1),
      Index2   (theIndex2),
      Distance (theDistance) {}
  };

  // Used by std::sort function
  static Standard_Boolean BRepExtrema_CheckPair_Comparator (const BRepExtrema_CheckPair& theLeft,
                                                            const BRepExtrema_CheckPair& theRight)
  {
    return (theLeft.Distance < theRight.Distance);
  }
}

//=======================================================================
//struct   : IndexBand
//purpose  : 
//=======================================================================
struct IndexBand
{
  IndexBand():
    First(0),
    Last(0)
  {
  }  
  
  IndexBand(Standard_Integer theFirtsIndex,
            Standard_Integer theLastIndex):
    First(theFirtsIndex),
    Last(theLastIndex)
  {
  }
  Standard_Integer First;
  Standard_Integer Last;
};

//=======================================================================
//struct   : ThreadSolution
//purpose  : 
//=======================================================================
struct ThreadSolution
{
  ThreadSolution(Standard_Integer theTaskNum):
    Shape1(0, theTaskNum-1),
    Shape2(0, theTaskNum-1),
    Dist(0, theTaskNum-1)
  {
    Dist.Init(DBL_MAX);
  }

  NCollection_Array1<BRepExtrema_SeqOfSolution> Shape1;
  NCollection_Array1<BRepExtrema_SeqOfSolution> Shape2;
  NCollection_Array1<Standard_Real>             Dist;
};

//=======================================================================
//struct   : VertexFunctor
//purpose  : 
//=======================================================================
struct VertexFunctor
{
  VertexFunctor(NCollection_Array1<IndexBand>* theBandArray,
                const Message_ProgressRange& theRange):
    BandArray(theBandArray),
    Solution(theBandArray->Size()),
    Map1(NULL),
    Map2(NULL),
    Scope(theRange, "Vertices distances calculating", theBandArray->Size()),
    Ranges(0, theBandArray->Size() - 1),
    Eps(Precision::Confusion()),
    StartDist(0.0)
  {
    for (Standard_Integer i = 0; i < theBandArray->Size(); ++i)
    {
      Ranges.SetValue(i, Scope.Next());
    }
  }

  void operator() (const Standard_Integer theIndex) const
  {
    const Standard_Integer aCount2 = Map2->Extent();
    const Standard_Integer aFirst = BandArray->Value(theIndex).First;
    const Standard_Integer aLast  = BandArray->Value(theIndex).Last;
    Solution.Dist[theIndex] = StartDist;

    Message_ProgressScope aScope(Ranges[theIndex], NULL, (double)aLast - aFirst);


    for (Standard_Integer anIdx1 = aFirst; anIdx1 <= aLast; ++anIdx1)
    {
      if (!aScope.More())
      {
        break;
      }
      aScope.Next();

      const TopoDS_Vertex& aVertex1 = TopoDS::Vertex(Map1->FindKey(anIdx1));
      const gp_Pnt aPoint1 = BRep_Tool::Pnt(aVertex1);
      for (Standard_Integer anIdx2 = 1; anIdx2 <= aCount2; ++anIdx2)
      {
        const TopoDS_Vertex& aVertex2 = TopoDS::Vertex(Map2->FindKey(anIdx2));
        const gp_Pnt aPoint2 = BRep_Tool::Pnt(aVertex2);
        const Standard_Real aDist = aPoint1.Distance(aPoint2);
        {
          if (aDist < Solution.Dist[theIndex] - Eps)
          { 
            const BRepExtrema_SolutionElem Sol1(aDist, aPoint1, BRepExtrema_IsVertex, aVertex1);
            const BRepExtrema_SolutionElem Sol2(aDist, aPoint2, BRepExtrema_IsVertex, aVertex2);

            Solution.Shape1[theIndex].Clear();
            Solution.Shape2[theIndex].Clear();
            Solution.Shape1[theIndex].Append(Sol1);
            Solution.Shape2[theIndex].Append(Sol2);
            
            Solution.Dist[theIndex] = aDist;
          }
          else if (Abs(aDist - Solution.Dist[theIndex]) < Eps)
          {
            const BRepExtrema_SolutionElem Sol1(aDist, aPoint1, BRepExtrema_IsVertex, aVertex1);
            const BRepExtrema_SolutionElem Sol2(aDist, aPoint2, BRepExtrema_IsVertex, aVertex2);
            Solution.Shape1[theIndex].Append(Sol1);
            Solution.Shape2[theIndex].Append(Sol2);

            if (Solution.Dist[theIndex] > aDist)
            {
              Solution.Dist[theIndex] = aDist;
            }
          }          
        }
      }
    }
  }

  NCollection_Array1<IndexBand>*            BandArray;
  mutable ThreadSolution                    Solution;
  const TopTools_IndexedMapOfShape*         Map1;
  const TopTools_IndexedMapOfShape*         Map2;
  Message_ProgressScope                     Scope;
  NCollection_Array1<Message_ProgressRange> Ranges;
  Standard_Real                             Eps;
  Standard_Real                             StartDist;
};

//=======================================================================
//function : DistanceVertVert
//purpose  : 
//=======================================================================
Standard_Boolean BRepExtrema_DistShapeShape::DistanceVertVert(const TopTools_IndexedMapOfShape& theMap1,
                                                              const TopTools_IndexedMapOfShape& theMap2,
                                                              const Message_ProgressRange& theRange)
{
  const Standard_Integer aCount1 = theMap1.Extent();
  const Standard_Integer aMinTaskSize = aCount1 < 10 ? aCount1 : 10;
  const Handle(OSD_ThreadPool)& aThreadPool = OSD_ThreadPool::DefaultPool();
  const Standard_Integer aNbThreads = aThreadPool->NbThreads();
  Standard_Integer aNbTasks = aNbThreads;
  Standard_Integer aTaskSize = (Standard_Integer) Ceiling((double) aCount1 / aNbTasks);
  if (aTaskSize < aMinTaskSize)
  {
    aTaskSize = aMinTaskSize;
    aNbTasks = (Standard_Integer) Ceiling((double) aCount1 / aTaskSize);
  }

  Standard_Integer aFirstIndex(1);
  NCollection_Array1<IndexBand> aBandArray(0, aNbTasks - 1);
  Message_ProgressScope aDistScope(theRange, NULL, 1);

  for (Standard_Integer anI = 0; anI < aBandArray.Size(); ++anI)
  {
    if (aCount1 < aFirstIndex + aTaskSize - 1)
    {
      aTaskSize = aCount1 - aFirstIndex + 1;
    }
    aBandArray.SetValue(anI, IndexBand(aFirstIndex, aFirstIndex + aTaskSize - 1));
    aFirstIndex += aTaskSize;
  }

  VertexFunctor aFunctor(&aBandArray, aDistScope.Next());
  aFunctor.Map1            = &theMap1;
  aFunctor.Map2            = &theMap2;
  aFunctor.StartDist       = myDistRef;
  aFunctor.Eps             = myEps;

  OSD_Parallel::For(0, aNbTasks, aFunctor, !myIsMultiThread);
  if (!aDistScope.More())
  {
    return Standard_False;
  }    
  for (Standard_Integer anI = 0; anI < aFunctor.Solution.Dist.Size(); ++anI)
  {
    Standard_Real aDist = aFunctor.Solution.Dist[anI];
    if (aDist < myDistRef - myEps)
    {
      mySolutionsShape1.Clear();
      mySolutionsShape2.Clear();
      mySolutionsShape1.Append(aFunctor.Solution.Shape1[anI]);
      mySolutionsShape2.Append(aFunctor.Solution.Shape2[anI]);
      myDistRef = aDist;
    }
    else if (Abs(aDist - myDistRef) < myEps)
    {
      mySolutionsShape1.Append(aFunctor.Solution.Shape1[anI]);
      mySolutionsShape2.Append(aFunctor.Solution.Shape2[anI]);
      myDistRef = aDist;
    }
  }
  return Standard_True;
}

//=======================================================================
//struct   : DistanceFunctor
//purpose  : 
//=======================================================================
struct DistanceFunctor
{
  DistanceFunctor(NCollection_Array1<NCollection_Array1<BRepExtrema_CheckPair> >* theArrayOfArrays,
                  const Message_ProgressRange& theRange):
    ArrayOfArrays(theArrayOfArrays), 
    Solution(ArrayOfArrays->Size()),
    Map1(NULL),
    Map2(NULL),
    LBox1(NULL),
    LBox2(NULL),
    Scope(theRange, "Shapes distances calculating", theArrayOfArrays->Size()),
    Ranges(0, theArrayOfArrays->Size() - 1),
    Eps(Precision::Confusion()),
    StartDist(0.0)
  {
    for (Standard_Integer i = 0; i < theArrayOfArrays->Size(); ++i)
    {
      Ranges.SetValue(i, Scope.Next());
    }
  }

  void operator() (const Standard_Integer theIndex) const
  {
    Message_ProgressScope aScope(Ranges[theIndex], NULL, ArrayOfArrays->Value(theIndex).Size());
    Solution.Dist[theIndex] = StartDist;
    for (Standard_Integer i = 0; i < ArrayOfArrays->Value(theIndex).Size(); i++)
    {
      if (!aScope.More())
      {
        return;
      }
      aScope.Next();
      const BRepExtrema_CheckPair& aPair = ArrayOfArrays->Value(theIndex).Value(i);
      if (aPair.Distance > Solution.Dist[theIndex] + Eps)
      {
        break; // early search termination
      }
      const Bnd_Box& aBox1 = LBox1->Value(aPair.Index1);
      const Bnd_Box& aBox2 = LBox2->Value(aPair.Index2);
      const TopoDS_Shape& aShape1 = Map1->FindKey(aPair.Index1);
      const TopoDS_Shape& aShape2 = Map2->FindKey(aPair.Index2);
      BRepExtrema_DistanceSS aDistTool(aShape1, aShape2, aBox1, aBox2, Solution.Dist[theIndex], Eps);
      const Standard_Real aDist = aDistTool.DistValue();
      if (aDistTool.IsDone())
      {
        if (aDist < Solution.Dist[theIndex] - Eps)
        {
          Solution.Shape1[theIndex].Clear();
          Solution.Shape2[theIndex].Clear();

          BRepExtrema_SeqOfSolution aSeq1 = aDistTool.Seq1Value();
          BRepExtrema_SeqOfSolution aSeq2 = aDistTool.Seq2Value();

          Solution.Shape1[theIndex].Append(aSeq1);
          Solution.Shape2[theIndex].Append(aSeq2);

          Solution.Dist[theIndex] = aDistTool.DistValue();
        }
        else if (Abs(aDist - Solution.Dist[theIndex]) < Eps)
        {
          BRepExtrema_SeqOfSolution aSeq1 = aDistTool.Seq1Value();
          BRepExtrema_SeqOfSolution aSeq2 = aDistTool.Seq2Value();

          Solution.Shape1[theIndex].Append(aSeq1);
          Solution.Shape2[theIndex].Append(aSeq2);
          if (Solution.Dist[theIndex] > aDist)
          {
            Solution.Dist[theIndex] = aDist;
          }
        }
      }
    }
  }

  NCollection_Array1<NCollection_Array1<BRepExtrema_CheckPair> >* ArrayOfArrays;
  mutable ThreadSolution                    Solution;
  const TopTools_IndexedMapOfShape*         Map1;
  const TopTools_IndexedMapOfShape*         Map2;
  const Bnd_Array1OfBox*                    LBox1;
  const Bnd_Array1OfBox*                    LBox2;
  Message_ProgressScope                     Scope;
  NCollection_Array1<Message_ProgressRange> Ranges;
  Standard_Real                             Eps;
  Standard_Real                             StartDist;
};


//=======================================================================
//struct   : DistancePairFunctor
//purpose  : 
//=======================================================================
struct DistancePairFunctor
{
  DistancePairFunctor(NCollection_Array1<IndexBand>* theBandArray,
                      const Message_ProgressRange& theRange):
    BandArray(theBandArray),
    PairList(0, theBandArray->Size() - 1),
    LBox1(NULL),
    LBox2(NULL),
    Scope(theRange, "Boxes distances calculating", theBandArray->Size()),
    Ranges(0, theBandArray->Size() - 1),
    DistRef(0),
    Eps(Precision::Confusion())
  {
    for (Standard_Integer i = 0; i < theBandArray->Size(); ++i)
    {
      Ranges.SetValue(i, Scope.Next());
    }
  }

  void operator() (const Standard_Integer theIndex) const
  {
    const Standard_Integer aFirst = BandArray->Value(theIndex).First;
    const Standard_Integer aLast  = BandArray->Value(theIndex).Last;

    Message_ProgressScope aScope(Ranges[theIndex], NULL, (double) aLast - aFirst);

    for (Standard_Integer anIdx1 = aFirst; anIdx1 <= aLast; ++anIdx1)
    {
      if (!aScope.More())
      {
        break;
      }
      aScope.Next();

      for (Standard_Integer anIdx2 = 1; anIdx2 <= LBox2->Size(); ++anIdx2)
      {
        const Bnd_Box& aBox1 = LBox1->Value(anIdx1);
        const Bnd_Box& aBox2 = LBox2->Value(anIdx2);
        if (aBox1.IsVoid() || aBox2.IsVoid())
        {
          continue;
        }

        const Standard_Real aDist = aBox1.Distance(aBox2);       
        if (aDist - DistRef < Eps)
        {
          PairList[theIndex].Append(BRepExtrema_CheckPair(anIdx1, anIdx2, aDist));
        }
      }
    }
  }

  Standard_Integer ListSize()
  {
    Standard_Integer aSize(0);
    for (Standard_Integer anI = PairList.Lower(); anI <= PairList.Upper(); ++anI)
    {
      aSize += PairList[anI].Size();
    }
    return aSize;
  }

  NCollection_Array1<IndexBand>*             BandArray;
  mutable NCollection_Array1<NCollection_Vector<BRepExtrema_CheckPair> > PairList;
  const Bnd_Array1OfBox*                     LBox1;
  const Bnd_Array1OfBox*                     LBox2;
  Message_ProgressScope                      Scope;
  NCollection_Array1<Message_ProgressRange>  Ranges;
  Standard_Real                              DistRef;
  Standard_Real                              Eps;
};

//=======================================================================
//function : DistanceMapMap
//purpose  : 
//=======================================================================

Standard_Boolean BRepExtrema_DistShapeShape::DistanceMapMap (const TopTools_IndexedMapOfShape& theMap1,
                                                             const TopTools_IndexedMapOfShape& theMap2,
                                                             const Bnd_Array1OfBox&            theLBox1,
                                                             const Bnd_Array1OfBox&            theLBox2,
                                                             const Message_ProgressRange&      theRange)
{
  const Standard_Integer aCount1 = theMap1.Extent();
  const Standard_Integer aCount2 = theMap2.Extent();

  if (aCount1 == 0 || aCount2 == 0)
  {
    return Standard_True;
  }

  Message_ProgressScope aTwinScope(theRange, NULL, 1.0);

  const Handle(OSD_ThreadPool)& aThreadPool = OSD_ThreadPool::DefaultPool();
  const Standard_Integer aNbThreads = aThreadPool->NbThreads();
  const Standard_Integer aMinPairTaskSize = aCount1 < 10 ? aCount1 : 10;
  Standard_Integer aNbPairTasks = aNbThreads;
  Standard_Integer aPairTaskSize = (Standard_Integer) Ceiling((double) aCount1 / aNbPairTasks);
  if (aPairTaskSize < aMinPairTaskSize)
  {
    aPairTaskSize = aMinPairTaskSize;
    aNbPairTasks = (Standard_Integer) Ceiling((double) aCount1 / aPairTaskSize);
  }

  Standard_Integer aFirstIndex(1);
  NCollection_Array1<IndexBand> aBandArray(0, aNbPairTasks - 1);

  for (Standard_Integer anI = 0; anI < aBandArray.Size(); ++anI)
  {
    if (aCount1 < aFirstIndex + aPairTaskSize - 1)
    {
      aPairTaskSize = aCount1 - aFirstIndex + 1;
    }
    aBandArray.SetValue(anI, IndexBand(aFirstIndex, aFirstIndex + aPairTaskSize - 1));
    aFirstIndex += aPairTaskSize;
  }

  aTwinScope.Next(0.15);
  DistancePairFunctor aPairFunctor(&aBandArray, aTwinScope.Next(0.15));
  aPairFunctor.LBox1 = &theLBox1;
  aPairFunctor.LBox2 = &theLBox2;
  aPairFunctor.DistRef = myDistRef;
  aPairFunctor.Eps = myEps;

  OSD_Parallel::For(0, aNbPairTasks, aPairFunctor, !myIsMultiThread);
  if (!aTwinScope.More())
  {
    return Standard_False;
  }
  Standard_Integer aListSize = aPairFunctor.ListSize();
  if(aListSize == 0)
  {
    return Standard_True;
  }
  NCollection_Array1<BRepExtrema_CheckPair> aPairList(0, aListSize-1);
  Standard_Integer aListIndex(0);
  for (Standard_Integer anI = 0; anI < aPairFunctor.PairList.Size(); ++anI)
  {
    for (Standard_Integer aJ = 0; aJ < aPairFunctor.PairList[anI].Size(); ++aJ)
    {
      aPairList[aListIndex] = aPairFunctor.PairList[anI][aJ];
      ++aListIndex;
    }
  }

  std::stable_sort(aPairList.begin(), aPairList.end(), BRepExtrema_CheckPair_Comparator);

  const Standard_Integer aMapSize = aPairList.Size();
  Standard_Integer aNbTasks = aMapSize < aNbThreads ? aMapSize : aNbThreads;
  Standard_Integer aTaskSize = (Standard_Integer) Ceiling((double) aMapSize / aNbTasks);
 
  NCollection_Array1<NCollection_Array1<BRepExtrema_CheckPair> > anArrayOfArray(0, aNbTasks - 1);
  // Since aPairList is sorted in ascending order of distances between Bnd_Boxes,
  // BRepExtrema_CheckPair are distributed to tasks one by one from smallest to largest,
  // and not ranges, as for DistancePairFunctor.
  // Since aMapSize may not be divisible entirely by the number of tasks,
  // some tasks should receive one BRepExtrema_CheckPair less than the rest.
  // aLastRowLimit defines the task number from which to start tasks containing
  // fewer BRepExtrema_CheckPair
  Standard_Integer aLastRowLimit = ((aMapSize % aNbTasks) == 0) ? aNbTasks : (aMapSize % aNbTasks);
  for (Standard_Integer anI = 0; anI < aTaskSize; ++anI)
  {
    for (Standard_Integer aJ = 0; aJ < aNbTasks; ++aJ)
    {
      if (anI == 0)
      {
        Standard_Integer aVectorSize = aTaskSize;
        if (aJ >= aLastRowLimit)
        {
          aVectorSize--;
        }
        anArrayOfArray[aJ].Resize(0, aVectorSize - 1, Standard_False);
      }
      if (anI < anArrayOfArray[aJ].Size())
      {
        anArrayOfArray[aJ][anI] = aPairList(anI*aNbTasks + aJ);
      }
      else
      {
        break;
      }
    }
  }
  DistanceFunctor aFunctor(&anArrayOfArray, aTwinScope.Next(0.85));
  aFunctor.Map1 = &theMap1;
  aFunctor.Map2 = &theMap2;
  aFunctor.LBox1 = &theLBox1;
  aFunctor.LBox2 = &theLBox2;
  aFunctor.Eps = myEps;
  aFunctor.StartDist = myDistRef;

  OSD_Parallel::For(0, aNbTasks, aFunctor, !myIsMultiThread);
  if (!aTwinScope.More())
  {
    return Standard_False;
  }

  for (Standard_Integer anI = 0; anI < aFunctor.Solution.Dist.Size(); ++anI)
  {
    Standard_Real aDist = aFunctor.Solution.Dist[anI];
    if (aDist < myDistRef - myEps)
    {
      mySolutionsShape1.Clear();
      mySolutionsShape2.Clear();
      mySolutionsShape1.Append(aFunctor.Solution.Shape1[anI]);
      mySolutionsShape2.Append(aFunctor.Solution.Shape2[anI]);
      myDistRef = aDist;
    }
    else if (Abs(aDist - myDistRef) < myEps)
    {
      mySolutionsShape1.Append(aFunctor.Solution.Shape1[anI]);
      mySolutionsShape2.Append(aFunctor.Solution.Shape2[anI]);
      if (myDistRef > aDist)
      {
        myDistRef = aDist;
      }
    }
  }
  return Standard_True;
}

//=======================================================================
//function : BRepExtrema_DistShapeShape
//purpose  : 
//=======================================================================

BRepExtrema_DistShapeShape::BRepExtrema_DistShapeShape()
: myDistRef (0.0),
  myIsDone (Standard_False),
  myInnerSol (Standard_False),
  myEps (Precision::Confusion()),
  myIsInitS1 (Standard_False),
  myIsInitS2 (Standard_False),
  myFlag (Extrema_ExtFlag_MINMAX),
  myAlgo (Extrema_ExtAlgo_Grad),
  myIsMultiThread(Standard_False)
{
}

//=======================================================================
//function : BRepExtrema_DistShapeShape
//purpose  : 
//=======================================================================
BRepExtrema_DistShapeShape::BRepExtrema_DistShapeShape(const TopoDS_Shape& Shape1,
                                                       const TopoDS_Shape& Shape2,
                                                       const Extrema_ExtFlag F,
                                                       const Extrema_ExtAlgo A,
                                                       const Message_ProgressRange& theRange)
: myDistRef (0.0),
  myIsDone (Standard_False),
  myInnerSol (Standard_False),
  myEps (Precision::Confusion()),
  myIsInitS1 (Standard_False),
  myIsInitS2 (Standard_False),
  myFlag (F),
  myAlgo (A),
  myIsMultiThread(Standard_False)
{
  LoadS1(Shape1);
  LoadS2(Shape2);
  Perform(theRange);
}

//=======================================================================
//function : BRepExtrema_DistShapeShape
//purpose  : 
//=======================================================================

BRepExtrema_DistShapeShape::BRepExtrema_DistShapeShape(const TopoDS_Shape& Shape1,
                                                       const TopoDS_Shape& Shape2,
                                                       const Standard_Real theDeflection,
                                                       const Extrema_ExtFlag F,
                                                       const Extrema_ExtAlgo A,
                                                       const Message_ProgressRange& theRange)
: myDistRef (0.0),
  myIsDone (Standard_False),
  myInnerSol (Standard_False),
  myEps (theDeflection),
  myIsInitS1 (Standard_False),
  myIsInitS2 (Standard_False),
  myFlag (F),
  myAlgo (A),
  myIsMultiThread(Standard_False)
{
  LoadS1(Shape1);
  LoadS2(Shape2);
  Perform(theRange);
}

//=======================================================================
//function : LoadS1
//purpose  : 
//=======================================================================

void BRepExtrema_DistShapeShape::LoadS1 (const TopoDS_Shape& Shape1)
{
  myShape1 = Shape1;
  myIsInitS1 = Standard_False;
  Decomposition (Shape1, myMapV1, myMapE1, myMapF1);
}

//=======================================================================
//function : LoadS2
//purpose  : 
//=======================================================================

void BRepExtrema_DistShapeShape::LoadS2 (const TopoDS_Shape& Shape2)
{
  myShape2 = Shape2;
  myIsInitS2 = Standard_False;
  Decomposition (Shape2, myMapV2, myMapE2, myMapF2);
}

//=======================================================================
//struct   : TreatmentFunctor
//purpose  : 
//=======================================================================
struct TreatmentFunctor
{
  TreatmentFunctor(NCollection_Array1<NCollection_Array1<TopoDS_Shape> >* theArrayOfArrays,
                   const Message_ProgressRange& theRange):
  ArrayOfArrays(theArrayOfArrays),
  SolutionsShape1(NULL),
  SolutionsShape2(NULL),
  Scope(theRange, "Search for the inner solid", theArrayOfArrays->Size()),
  Ranges(0, theArrayOfArrays->Size() - 1),
  DistRef(0),
  InnerSol(NULL),
  IsDone(NULL),
  Mutex(NULL)
  {
    for (Standard_Integer i = 0; i < theArrayOfArrays->Size(); ++i)
    {
      Ranges.SetValue(i, Scope.Next());
    }
  }

  void operator() (const Standard_Integer theIndex) const
  {
    const Standard_Real aTolerance = 0.001;
    Message_ProgressScope aScope(Ranges[theIndex], NULL, ArrayOfArrays->Value(theIndex).Size());
    BRepClass3d_SolidClassifier aClassifier(Shape);

    for (Standard_Integer i = 0; i < ArrayOfArrays->Value(theIndex).Size(); i++)
    {
      if (!aScope.More())
      {
        break;
      }
      aScope.Next();
      if (*IsDone)
      {
        break;
      }

      const TopoDS_Vertex& aVertex = TopoDS::Vertex(ArrayOfArrays->Value(theIndex).Value(i));
      const gp_Pnt aPnt = BRep_Tool::Pnt(aVertex);
      aClassifier.Perform(aPnt, aTolerance);
      if (aClassifier.State() == TopAbs_IN)
      {
        Standard_Mutex::Sentry aLock(Mutex.get());
        *InnerSol = Standard_True;
        *DistRef  = 0.;
        *IsDone   = Standard_True;
        BRepExtrema_SolutionElem aSolElem(0, aPnt, BRepExtrema_IsVertex, aVertex);
        SolutionsShape1->Append(aSolElem);
        SolutionsShape2->Append(aSolElem);
        break;
      }
    }
  }

  NCollection_Array1<NCollection_Array1<TopoDS_Shape> >* ArrayOfArrays;
  BRepExtrema_SeqOfSolution*                 SolutionsShape1;
  BRepExtrema_SeqOfSolution*                 SolutionsShape2;
  TopoDS_Shape                               Shape;
  Message_ProgressScope                      Scope;
  NCollection_Array1<Message_ProgressRange>  Ranges;
  Standard_Real*                             DistRef;
  volatile Standard_Boolean*                 InnerSol;
  volatile Standard_Boolean*                 IsDone;
  Handle(Standard_HMutex)                    Mutex;
};

//=======================================================================
//function : SolidTreatment
//purpose  : 
//=======================================================================
Standard_Boolean BRepExtrema_DistShapeShape::SolidTreatment(const TopoDS_Shape& theShape,
                                                            const TopTools_IndexedMapOfShape& theVertexMap,
                                                            const Message_ProgressRange& theRange)
{
  const Standard_Integer aMapSize = theVertexMap.Extent();
  const Standard_Integer aMinTaskSize = 3;
  const Handle(OSD_ThreadPool)& aThreadPool = OSD_ThreadPool::DefaultPool();
  const Standard_Integer aNbThreads = aThreadPool->NbThreads();
  Standard_Integer aNbTasks = aNbThreads * 10;
  Standard_Integer aTaskSize = (Standard_Integer) Ceiling((double) aMapSize / aNbTasks);
  if (aTaskSize < aMinTaskSize)
  {
    aTaskSize = aMinTaskSize;
    aNbTasks = (Standard_Integer) Ceiling((double) aMapSize / aTaskSize);
  }

  NCollection_Array1< NCollection_Array1<TopoDS_Shape> > anArrayOfArray(0, aNbTasks - 1);
  for (Standard_Integer anI = 1; anI <= aMapSize; ++anI)
  {
    Standard_Integer aVectIndex = (anI - 1) / aTaskSize;
    Standard_Integer aShapeIndex = (anI - 1) % aTaskSize;
    if (aShapeIndex == 0)
    {
      Standard_Integer aVectorSize = aTaskSize;
      Standard_Integer aTailSize = aMapSize - aVectIndex * aTaskSize;
      if (aTailSize < aTaskSize)
      {
        aVectorSize = aTailSize;
      }
      anArrayOfArray[aVectIndex].Resize(0, aVectorSize - 1, Standard_False);
    }
    anArrayOfArray[aVectIndex][aShapeIndex] = theVertexMap(anI);
  }

  Message_ProgressScope aScope(theRange, "Solid treatment", aNbTasks);
  TreatmentFunctor aFunctor(&anArrayOfArray, aScope.Next());
  aFunctor.SolutionsShape1 = &mySolutionsShape1;
  aFunctor.SolutionsShape2 = &mySolutionsShape2;
  aFunctor.Shape = theShape;
  aFunctor.DistRef = &myDistRef;
  aFunctor.InnerSol = &myInnerSol;
  aFunctor.IsDone = &myIsDone;
  if (myIsMultiThread)
  {
    aFunctor.Mutex.reset(new Standard_HMutex());
  }

  OSD_Parallel::For(0, aNbTasks, aFunctor, !myIsMultiThread);

  if (!aScope.More())
  {
    return Standard_False;
  }
  return Standard_True;
}

//=======================================================================
//function : Perform
//purpose  : 
//=======================================================================

Standard_Boolean BRepExtrema_DistShapeShape::Perform(const Message_ProgressRange& theRange)
{
  myIsDone = Standard_False;
  myInnerSol = Standard_False;
  mySolutionsShape1.Clear();
  mySolutionsShape2.Clear();

  if (myShape1.IsNull() || myShape2.IsNull())
    return Standard_False;

  // Treatment of solids
  Standard_Boolean anIsSolid1 = (myShape1.ShapeType() == TopAbs_SOLID) ||
    (myShape1.ShapeType() == TopAbs_COMPSOLID);
  Standard_Boolean anIsSolid2 = (myShape2.ShapeType() == TopAbs_SOLID) ||
    (myShape2.ShapeType() == TopAbs_COMPSOLID);
  Standard_Integer aRootStepsNum = 9; // By num of DistanceMapMap calls
  aRootStepsNum = anIsSolid1 ? aRootStepsNum + 1 : aRootStepsNum;
  aRootStepsNum = anIsSolid2 ? aRootStepsNum + 1 : aRootStepsNum;
  Message_ProgressScope aRootScope(theRange, "calculating distance", aRootStepsNum);

  if (anIsSolid1)
  {
    if (!SolidTreatment(myShape1, myMapV2, aRootScope.Next()))
    {
      return Standard_False;
    }
  }

  if (anIsSolid2 && (!myInnerSol))
  {
    if (!SolidTreatment(myShape2, myMapV1, aRootScope.Next()))
    {
      return Standard_False;
    }
  }

  if (!myInnerSol)
  {
    if (!myIsInitS1) // rebuild cached data for 1st shape
    {
      if (!myMapV1.IsEmpty())
      {
        myBV1.Resize(1, myMapV1.Extent(), Standard_False);
      }
      if (!myMapE1.IsEmpty())
      {
        myBE1.Resize(1, myMapE1.Extent(), Standard_False);
      }
      if (!myMapF1.IsEmpty())
      {
        myBF1.Resize(1, myMapF1.Extent(), Standard_False);
      }

      BoxCalculation (myMapV1, myBV1);
      BoxCalculation (myMapE1, myBE1);
      BoxCalculation (myMapF1, myBF1);

      myIsInitS1 = Standard_True;
    }

    if (!myIsInitS2) // rebuild cached data for 2nd shape
    {
      if (!myMapV2.IsEmpty())
      {
        myBV2.Resize(1, myMapV2.Extent(), Standard_False);
      }
      if (!myMapE2.IsEmpty())
      {
        myBE2.Resize(1, myMapE2.Extent(), Standard_False);
      }
      if (!myMapF2.IsEmpty())
      {
        myBF2.Resize(1, myMapF2.Extent(), Standard_False);
      }

      BoxCalculation (myMapV2, myBV2);
      BoxCalculation (myMapE2, myBE2);
      BoxCalculation (myMapF2, myBF2);

      myIsInitS2 = Standard_True;
    }

    if (myMapV1.Extent() && myMapV2.Extent())
    {
      const TopoDS_Vertex& V1 = TopoDS::Vertex(myMapV1(1));
      const TopoDS_Vertex& V2 = TopoDS::Vertex(myMapV2(1));
      myDistRef = DistanceInitiale(V1, V2);
    }
    else
      myDistRef = 1.e30; //szv:!!!

    if (!DistanceVertVert(myMapV1, myMapV2, aRootScope.Next()))
    {
      return Standard_False;
    }
    if (!DistanceMapMap(myMapV1, myMapE2, myBV1, myBE2, aRootScope.Next()))
    {
      return Standard_False;
    }
    if (!DistanceMapMap(myMapE1, myMapV2, myBE1, myBV2, aRootScope.Next()))
    {
      return Standard_False;
    }
    if (!DistanceMapMap(myMapV1, myMapF2, myBV1, myBF2, aRootScope.Next()))
    {
      return Standard_False;
    }
    if (!DistanceMapMap(myMapF1, myMapV2, myBF1, myBV2, aRootScope.Next()))
    {
      return Standard_False;
    }
    if (!DistanceMapMap(myMapE1, myMapE2, myBE1, myBE2, aRootScope.Next()))
    {
      return Standard_False;
    }
    if (!DistanceMapMap(myMapE1, myMapF2, myBE1, myBF2, aRootScope.Next()))
    {
      return Standard_False;
    }
    if (!DistanceMapMap(myMapF1, myMapE2, myBF1, myBE2, aRootScope.Next()))
    {
      return Standard_False;
    }

    if (Abs(myDistRef) > myEps)
    {
      if (!DistanceMapMap(myMapF1, myMapF2, myBF1, myBF2, aRootScope.Next()))
      {
        return Standard_False;
      }
    }

    //  Modified by Sergey KHROMOV - Tue Mar  6 11:55:03 2001 Begin
    Standard_Integer i = 1;
    for (; i <= mySolutionsShape1.Length(); i++)
      if (mySolutionsShape1.Value(i).Dist() > myDistRef + myEps)
      {
        mySolutionsShape1.Remove(i);
        mySolutionsShape2.Remove(i);
      }
    //  Modified by Sergey KHROMOV - Tue Mar  6 11:55:04 2001 End
    myIsDone = (mySolutionsShape1.Length() > 0);
  }

  return myIsDone;
}

//=======================================================================
//function : Value
//purpose  : 
//=======================================================================

Standard_Real BRepExtrema_DistShapeShape::Value() const 
{ 
  if (!myIsDone)
    throw StdFail_NotDone("BRepExtrema_DistShapeShape::Value: There's no solution ");

  return myDistRef;
}

//=======================================================================
//function : SupportOnShape1
//purpose  : 
//=======================================================================

TopoDS_Shape BRepExtrema_DistShapeShape::SupportOnShape1(const Standard_Integer N) const
{ 
  if (!myIsDone)
    throw StdFail_NotDone("BRepExtrema_DistShapeShape::SupportOnShape1: There's no solution ");

  const BRepExtrema_SolutionElem &sol = mySolutionsShape1.Value(N);
  switch (sol.SupportKind())
  {
    case BRepExtrema_IsVertex : return sol.Vertex();
    case BRepExtrema_IsOnEdge : return sol.Edge();
    case BRepExtrema_IsInFace : return sol.Face();
  }
  return TopoDS_Shape();
}

//=======================================================================
//function : SupportOnShape2
//purpose  : 
//=======================================================================

TopoDS_Shape BRepExtrema_DistShapeShape::SupportOnShape2(const Standard_Integer N) const 
{ 
  if (!myIsDone)
    throw StdFail_NotDone("BRepExtrema_DistShapeShape::SupportOnShape2: There's no solution ");

  const BRepExtrema_SolutionElem &sol = mySolutionsShape2.Value(N);
  switch (sol.SupportKind())
  {
    case BRepExtrema_IsVertex : return sol.Vertex();
    case BRepExtrema_IsOnEdge : return sol.Edge();
    case BRepExtrema_IsInFace : return sol.Face();
  }
  return TopoDS_Shape();
}

//=======================================================================
//function : ParOnEdgeS1
//purpose  : 
//=======================================================================

void BRepExtrema_DistShapeShape::ParOnEdgeS1(const Standard_Integer N, Standard_Real& t) const 
{ 
  if (!myIsDone)
    throw StdFail_NotDone("BRepExtrema_DistShapeShape::ParOnEdgeS1: There's no solution");

  const BRepExtrema_SolutionElem &sol = mySolutionsShape1.Value(N);
  if (sol.SupportKind() != BRepExtrema_IsOnEdge)
    throw BRepExtrema_UnCompatibleShape("BRepExtrema_DistShapeShape::ParOnEdgeS1: ParOnEdgeS1 is impossible without EDGE");

  sol.EdgeParameter(t);
}

//=======================================================================
//function : ParOnEdgeS2
//purpose  : 
//=======================================================================

void BRepExtrema_DistShapeShape::ParOnEdgeS2(const Standard_Integer N,  Standard_Real& t) const 
{ 
  if (!myIsDone)
    throw StdFail_NotDone("BRepExtrema_DistShapeShape::ParOnEdgeS2: There's no solution");

  const BRepExtrema_SolutionElem &sol = mySolutionsShape2.Value(N);
  if (sol.SupportKind() != BRepExtrema_IsOnEdge)
    throw BRepExtrema_UnCompatibleShape("BRepExtrema_DistShapeShape::ParOnEdgeS2: ParOnEdgeS2 is impossible without EDGE");
 
  sol.EdgeParameter(t);
}

//=======================================================================
//function : ParOnFaceS1
//purpose  : 
//=======================================================================

void BRepExtrema_DistShapeShape::ParOnFaceS1(const Standard_Integer N,  Standard_Real& u,  Standard_Real& v) const 
{ 
  if (!myIsDone)
    throw StdFail_NotDone("BRepExtrema_DistShapeShape::ParOnFaceS1: There's no solution");

  const BRepExtrema_SolutionElem &sol = mySolutionsShape1.Value(N);
  if (sol.SupportKind() != BRepExtrema_IsInFace)
    throw BRepExtrema_UnCompatibleShape("BRepExtrema_DistShapeShape::ParOnFaceS1: ParOnFaceS1 is impossible without FACE");
  
  sol.FaceParameter(u, v);
}

//=======================================================================
//function : ParOnFaceS2
//purpose  : 
//=======================================================================

void BRepExtrema_DistShapeShape::ParOnFaceS2(const Standard_Integer N,  Standard_Real& u, Standard_Real& v) const 
{ 
  if (!myIsDone)
    throw StdFail_NotDone("BRepExtrema_DistShapeShape::ParOnFaceS2: There's no solution");

  const BRepExtrema_SolutionElem &sol = mySolutionsShape2.Value(N);
  if (sol.SupportKind() != BRepExtrema_IsInFace)
    throw BRepExtrema_UnCompatibleShape("BRepExtrema_DistShapeShape::ParOnFaceS2:ParOnFaceS2 is impossible without FACE ");
  
  sol.FaceParameter(u, v);
}

//=======================================================================
//function : Dump
//purpose  : 
//=======================================================================

void BRepExtrema_DistShapeShape::Dump(Standard_OStream& o) const 
{
  Standard_Integer i;
  Standard_Real r1,r2;
  
  o<< "the distance  value is :  " << Value()<<std::endl;
  o<< "the number of solutions is :"<<NbSolution()<<std::endl;
  o<<std::endl;
  for (i=1;i<=NbSolution();i++)
  {
    o<<"solution number "<<i<<": "<< std::endl;
    o<<"the type of the solution on the first shape is " <<Standard_Integer( SupportTypeShape1(i)) <<std::endl; 
    o<<"the type of the solution on the second shape is "<<Standard_Integer( SupportTypeShape2(i))<< std::endl;
    o<< "the coordinates of  the point on the first shape are: "<<std::endl; 
    o<<"X=" <<PointOnShape1(i).X()<<" Y=" <<PointOnShape1(i).Y()<<" Z="<<PointOnShape1(i).Z()<<std::endl;
    o<< "the coordinates of  the point on the second shape are: "<<std::endl; 
    o<<"X="<< PointOnShape2(i).X()<< " Y="<<PointOnShape2(i).Y()<<" Z="<< PointOnShape2(i).Z()<<std::endl;
    
    switch (SupportTypeShape1(i))
    {
      case BRepExtrema_IsVertex:
        break;
      case BRepExtrema_IsOnEdge:
        ParOnEdgeS1(i,r1);
        o << "parameter on the first edge :  t= " << r1 << std::endl;
        break;
      case BRepExtrema_IsInFace:
        ParOnFaceS1(i,r1,r2);
        o << "parameters on the first face :  u= " << r1 << " v=" <<  r2 << std::endl;
        break;
    }
    switch (SupportTypeShape2(i))
    {
      case BRepExtrema_IsVertex:
        break;
      case BRepExtrema_IsOnEdge:
        ParOnEdgeS2(i,r1);
        o << "parameter on the second edge : t=" << r1 << std::endl;
        break;
      case BRepExtrema_IsInFace:
        ParOnFaceS2(i,r1,r2);
        o << "parameters on the second face : u= " << r1 << " v=" <<  r2 << std::endl;
        break;
    }
    o<<std::endl;
  } 
}