// Created on: 2016-04-19
// Copyright (c) 2016 OPEN CASCADE SAS
// Created by: Oleg AGASHIN
//
// 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.

#include <BRepMesh_ShapeTool.hxx>
#include <IMeshData_Edge.hxx>
#include <IMeshData_PCurve.hxx>
#include <TopoDS_Vertex.hxx>
#include <TopExp.hxx>
#include <TopExp_Explorer.hxx>
#include <BRep_Tool.hxx>
#include <BRep_Builder.hxx>
#include <ShapeAnalysis_Edge.hxx>
#include <BRepAdaptor_Curve.hxx>
#include <Precision.hxx>
#include <Bnd_Box.hxx>

namespace
{
  //! Auxilary struct to take a tolerance of edge.
  struct EdgeTolerance
  {
    static Standard_Real Get(const TopoDS_Shape& theEdge)
    {
      return BRep_Tool::Tolerance(TopoDS::Edge(theEdge));
    }
  };

  //! Auxilary struct to take a tolerance of vertex.
  struct VertexTolerance
  {
    static Standard_Real Get(const TopoDS_Shape& theVertex)
    {
      return BRep_Tool::Tolerance(TopoDS::Vertex(theVertex));
    }
  };

  //! Returns maximum tolerance of face element of the specified type.
  template<TopAbs_ShapeEnum ShapeType, class ToleranceExtractor>
  Standard_Real MaxTolerance(const TopoDS_Face& theFace)
  {
    Standard_Real aMaxTolerance = RealFirst();
    TopExp_Explorer aExplorer(theFace, ShapeType);
    for (; aExplorer.More(); aExplorer.Next())
    {
      Standard_Real aTolerance = ToleranceExtractor::Get(aExplorer.Current());
      if (aTolerance > aMaxTolerance)
        aMaxTolerance = aTolerance;
    }

    return aMaxTolerance;
  }
}

//=======================================================================
//function : MaxFaceTolerance
//purpose  : 
//=======================================================================
Standard_Real BRepMesh_ShapeTool::MaxFaceTolerance(const TopoDS_Face& theFace)
{
  Standard_Real aMaxTolerance = BRep_Tool::Tolerance(theFace);

  Standard_Real aTolerance = Max(
    MaxTolerance<TopAbs_EDGE, EdgeTolerance  >(theFace),
    MaxTolerance<TopAbs_VERTEX, VertexTolerance>(theFace));

  return Max(aMaxTolerance, aTolerance);
}

//=======================================================================
//function : BoxMaxDimension
//purpose  : 
//=======================================================================
void BRepMesh_ShapeTool::BoxMaxDimension(const Bnd_Box& theBox,
                                         Standard_Real& theMaxDimension)
{
  if (theBox.IsVoid())
    return;

  Standard_Real aMinX, aMinY, aMinZ, aMaxX, aMaxY, aMaxZ;
  theBox.Get(aMinX, aMinY, aMinZ, aMaxX, aMaxY, aMaxZ);

  theMaxDimension = Max(aMaxX - aMinX, Max(aMaxY - aMinY, aMaxZ - aMinZ));
}

//=======================================================================
//function : CheckAndUpdateFlags
//purpose  : 
//=======================================================================
void BRepMesh_ShapeTool::CheckAndUpdateFlags (
  const IMeshData::IEdgeHandle&   theEdge,
  const IMeshData::IPCurveHandle& thePCurve)
{
  if (!theEdge->GetSameParam () &&
      !theEdge->GetSameRange () &&
       theEdge->GetDegenerated ())
  {
    // Nothing to do worse.
    return;
  }

  const TopoDS_Edge& aEdge = theEdge->GetEdge ();
  const TopoDS_Face& aFace = thePCurve->GetFace ()->GetFace ();

  Handle (Geom_Curve) aCurve;
  Standard_Real aFirstParam, aLastParam;
  Range (aEdge, aCurve, aFirstParam, aLastParam);
  if (aCurve.IsNull())
  {
    theEdge->SetDegenerated(Standard_True);
    return;
  }

  BRepAdaptor_Curve aCurveOnSurf(aEdge, aFace);
  if (theEdge->GetSameParam () || theEdge->GetSameRange ())
  {
    if (theEdge->GetSameRange ())
    {
      const Standard_Real aDiffFirst = aCurveOnSurf.FirstParameter () - aFirstParam;
      const Standard_Real aDiffLast  = aCurveOnSurf.LastParameter ()  - aLastParam;
      theEdge->SetSameRange (
        Abs (aDiffFirst) < Precision::PConfusion () &&
        Abs (aDiffLast ) < Precision::PConfusion ());

      if (!theEdge->GetSameRange())
      {
        theEdge->SetSameParam(Standard_False);
      }
    }
  }

  if (!theEdge->GetDegenerated ()/* || theEdge->GetSameParam ()*/)
  {
    TopoDS_Vertex aStartVertex, aEndVertex;
    TopExp::Vertices (aEdge, aStartVertex, aEndVertex);
    if (aStartVertex.IsNull() || aEndVertex.IsNull())
    {
      theEdge->SetDegenerated(Standard_True);
      return;
    }

    if (aStartVertex.IsSame(aEndVertex))
    {
      const Standard_Integer aPointsNb          = 20;
      const Standard_Real    aVertexTolerance   = BRep_Tool::Tolerance (aStartVertex);
      const Standard_Real    aDu                = (aLastParam - aFirstParam) / aPointsNb;
      //const Standard_Real    aEdgeTolerance     = BRep_Tool::Tolerance (aEdge);
      //const Standard_Real    aSqEdgeTolerance   = aEdgeTolerance * aEdgeTolerance;

      gp_Pnt aPrevPnt;
      aCurve->D0 (aFirstParam, aPrevPnt);

      Standard_Real aLength = 0.0;
      for (Standard_Integer i = 1; i <= aPointsNb; ++i)
      {
        const Standard_Real aParameter = aFirstParam + i * aDu;
        // Calculation of the length of the edge in 3D
        // in order to check degenerativity
        gp_Pnt aPnt;
        aCurve->D0 (aParameter, aPnt);
        aLength += aPrevPnt.Distance (aPnt);

        //if (theEdge->GetSameParam ())
        //{
        //  // Check that points taken at the 3d and pcurve using 
        //  // same parameter are within tolerance of an edge.
        //  gp_Pnt aPntOnSurf;
        //  aCurveOnSurf.D0 (aParameter, aPntOnSurf);
        //  theEdge->SetSameParam (aPnt.SquareDistance (aPntOnSurf) < aSqEdgeTolerance);
        //}

        if (aLength > aVertexTolerance /*&& !theEdge->GetSameParam()*/)
        {
          break;
        }

        aPrevPnt = aPnt;
      }

      theEdge->SetDegenerated (aLength < aVertexTolerance);
    }
  }
}

//=======================================================================
//function : AddInFace
//purpose  : 
//=======================================================================
void BRepMesh_ShapeTool::AddInFace(
  const TopoDS_Face&          theFace,
  Handle(Poly_Triangulation)& theTriangulation)
{
  const TopLoc_Location& aLoc = theFace.Location();
  if (!aLoc.IsIdentity())
  {
    gp_Trsf aTrsf = aLoc.Transformation();
    aTrsf.Invert();

    TColgp_Array1OfPnt& aNodes = theTriangulation->ChangeNodes();
    for (Standard_Integer i = aNodes.Lower(); i <= aNodes.Upper(); ++i)
      aNodes(i).Transform(aTrsf);
  }

  BRep_Builder aBuilder;
  aBuilder.UpdateFace(theFace, theTriangulation);
}


//=======================================================================
//function : NullifyFace
//purpose  : 
//=======================================================================
void BRepMesh_ShapeTool::NullifyFace (const TopoDS_Face& theFace)
{
  BRep_Builder aBuilder;
  aBuilder.UpdateFace (theFace, Handle (Poly_Triangulation)());
}

//=======================================================================
//function : NullifyEdge
//purpose  : 
//=======================================================================
void BRepMesh_ShapeTool::NullifyEdge (
  const TopoDS_Edge&                 theEdge,
  const Handle (Poly_Triangulation)& theTriangulation,
  const TopLoc_Location&             theLocation)
{
  UpdateEdge (theEdge, Handle (Poly_PolygonOnTriangulation)(),
    theTriangulation, theLocation);
}

//=======================================================================
//function : NullifyEdge
//purpose  : 
//=======================================================================
void BRepMesh_ShapeTool::NullifyEdge (
  const TopoDS_Edge&     theEdge,
  const TopLoc_Location& theLocation)
{
  BRep_Builder aBuilder;
  aBuilder.UpdateEdge (theEdge, Handle (Poly_Polygon3D)(), theLocation);
}

//=======================================================================
//function : UpdateEdge
//purpose  : 
//=======================================================================
void BRepMesh_ShapeTool::UpdateEdge (
  const TopoDS_Edge&                          theEdge,
  const Handle (Poly_PolygonOnTriangulation)& thePolygon,
  const Handle (Poly_Triangulation)&          theTriangulation,
  const TopLoc_Location&                      theLocation)
{
  BRep_Builder aBuilder;
  aBuilder.UpdateEdge (theEdge, thePolygon, theTriangulation, theLocation);
}

//=======================================================================
//function : UpdateEdge
//purpose  : 
//=======================================================================
void BRepMesh_ShapeTool::UpdateEdge (
  const TopoDS_Edge&                          theEdge,
  const Handle (Poly_PolygonOnTriangulation)& thePolygon1,
  const Handle (Poly_PolygonOnTriangulation)& thePolygon2,
  const Handle (Poly_Triangulation)&          theTriangulation,
  const TopLoc_Location&                      theLocation)
{
  BRep_Builder aBuilder;
  aBuilder.UpdateEdge (theEdge, thePolygon1, thePolygon2,
    theTriangulation, theLocation);
}

//=======================================================================
//function : UpdateEdge
//purpose  : 
//=======================================================================
void BRepMesh_ShapeTool::UpdateEdge(
  const TopoDS_Edge&            theEdge,
  const Handle(Poly_Polygon3D)& thePolygon)
{
  BRep_Builder aBuilder;
  aBuilder.UpdateEdge(theEdge, thePolygon);
}

//=======================================================================
//function : UseLocation
//purpose  : 
//=======================================================================
gp_Pnt BRepMesh_ShapeTool::UseLocation (
  const gp_Pnt&          thePnt,
  const TopLoc_Location& theLoc)
{
  if (theLoc.IsIdentity())
  {
    return thePnt;
  }

  return thePnt.Transformed (theLoc.Transformation ());
}

//=======================================================================
//function : UVPoints
//purpose  : 
//=======================================================================
Standard_Boolean BRepMesh_ShapeTool::UVPoints (
  const TopoDS_Edge&      theEdge,
  const TopoDS_Face&      theFace,
  gp_Pnt2d&               theFirstPoint2d,
  gp_Pnt2d&               theLastPoint2d,
  const Standard_Boolean  isConsiderOrientation)
{

  Handle (Geom2d_Curve) aCurve2d;
  Standard_Real aFirstParam, aLastParam;
  if (!Range(theEdge, theFace, aCurve2d, aFirstParam, aLastParam, isConsiderOrientation))
  {
    return Standard_False;
  }

  aCurve2d->D0 (aFirstParam, theFirstPoint2d);
  aCurve2d->D0 (aLastParam,  theLastPoint2d);
  return Standard_True;
}

//=======================================================================
//function : Range
//purpose  :
//=======================================================================
Standard_Boolean BRepMesh_ShapeTool::Range (
  const TopoDS_Edge&      theEdge,
  const TopoDS_Face&      theFace,
  Handle (Geom2d_Curve)&  thePCurve,
  Standard_Real&          theFirstParam,
  Standard_Real&          theLastParam,
  const Standard_Boolean  isConsiderOrientation)
{

  ShapeAnalysis_Edge aEdge;
  return aEdge.PCurve (theEdge, theFace, thePCurve,
    theFirstParam, theLastParam,
    isConsiderOrientation);
}

//=======================================================================
//function : Range
//purpose  :
//=======================================================================
Standard_Boolean BRepMesh_ShapeTool::Range (
  const TopoDS_Edge&      theEdge,
  Handle (Geom_Curve)&    theCurve,
  Standard_Real&          theFirstParam,
  Standard_Real&          theLastParam,
  const Standard_Boolean  isConsiderOrientation)
{

  ShapeAnalysis_Edge aEdge;
  return aEdge.Curve3d (theEdge, theCurve,
    theFirstParam, theLastParam,
    isConsiderOrientation);
}