// 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_CurveTessellator.hxx>
#include <gp_Pnt.hxx>
#include <BRep_Tool.hxx>
#include <TopoDS_Edge.hxx>
#include <IMeshData_Edge.hxx>
#include <IMeshData_PCurve.hxx>
#include <IMeshTools_Parameters.hxx>
#include <TopExp_Explorer.hxx>
#include <Geom_Plane.hxx>
#include <TopExp.hxx>
#include <Adaptor3d_HCurveOnSurface.hxx>
#include <Adaptor2d_HCurve2d.hxx>
#include <Standard_Failure.hxx>
#include <GCPnts_AbscissaPoint.hxx>

//=======================================================================
//function : Constructor
//purpose  : 
//=======================================================================
BRepMesh_CurveTessellator::BRepMesh_CurveTessellator(
  const IMeshData::IEdgeHandle& theEdge,
  const IMeshTools_Parameters&  theParameters)
  : myDEdge(theEdge),
    myParameters(theParameters),
    myEdge(theEdge->GetEdge()),
    myCurve(myEdge)
{
  init();
}

//=======================================================================
//function : Constructor
//purpose  : 
//=======================================================================
BRepMesh_CurveTessellator::BRepMesh_CurveTessellator (
  const IMeshData::IEdgeHandle& theEdge,
  const TopAbs_Orientation      theOrientation,
  const IMeshData::IFaceHandle& theFace,
  const IMeshTools_Parameters&  theParameters)
  : myDEdge(theEdge),
    myParameters(theParameters),
    myEdge(TopoDS::Edge(theEdge->GetEdge().Oriented(theOrientation))),
    myCurve(myEdge, theFace->GetFace())
{
  init();
}

//=======================================================================
//function : init
//purpose  : 
//=======================================================================
void BRepMesh_CurveTessellator::init()
{
  if (myParameters.MinSize <= 0.0)
  {
    Standard_Failure::Raise ("The structure \"myParameters\" is not initialized");
  }

  TopExp::Vertices(myEdge, myFirstVertex, myLastVertex);

  Standard_Real aPreciseAngDef = 0.5 * myDEdge->GetAngularDeflection();
  Standard_Real aPreciseLinDef = 0.5 * myDEdge->GetDeflection();
  if (myEdge.Orientation() == TopAbs_INTERNAL)
  {
    aPreciseLinDef *= 0.5;
  }

  aPreciseLinDef = Max (aPreciseLinDef, Precision::Confusion());
  aPreciseAngDef = Max (aPreciseAngDef, Precision::Angular());

  Standard_Real aMinSize = myParameters.MinSize;
  if (myParameters.AdjustMinSize)
  {
    aMinSize = Min (aMinSize, myParameters.RelMinSize() * GCPnts_AbscissaPoint::Length (
      myCurve, myCurve.FirstParameter(), myCurve.LastParameter(), aPreciseLinDef));
  }

  mySquareEdgeDef = aPreciseLinDef * aPreciseLinDef;
  mySquareMinSize = Max (mySquareEdgeDef, aMinSize * aMinSize);

  myEdgeSqTol  = BRep_Tool::Tolerance (myEdge);
  myEdgeSqTol *= myEdgeSqTol;

  const Standard_Integer aMinPntNb = (myCurve.GetType() == GeomAbs_Circle) ? 4 : 2; //OCC287

  myDiscretTool.Initialize (myCurve,
                            myCurve.FirstParameter(), myCurve.LastParameter(),
                            aPreciseAngDef, aPreciseLinDef, aMinPntNb,
                            Precision::PConfusion(), aMinSize);

  if (myCurve.IsCurveOnSurface())
  {
    const Adaptor3d_CurveOnSurface& aCurve = myCurve.CurveOnSurface();
    const Handle(Adaptor3d_HSurface)& aSurface = aCurve.GetSurface();

    const Standard_Real aTol = Precision::Confusion();
    const Standard_Real aDu = aSurface->UResolution(aTol);
    const Standard_Real aDv = aSurface->VResolution(aTol);

    myFaceRangeU[0] = aSurface->FirstUParameter() - aDu;
    myFaceRangeU[1] = aSurface->LastUParameter()  + aDu;

    myFaceRangeV[0] = aSurface->FirstVParameter() - aDv;
    myFaceRangeV[1] = aSurface->LastVParameter()  + aDv;
  }

  addInternalVertices();
  splitByDeflection2d();
}

//=======================================================================
//function : Destructor
//purpose  : 
//=======================================================================
BRepMesh_CurveTessellator::~BRepMesh_CurveTessellator ()
{
}

//=======================================================================
//function : NbPoints
//purpose  : 
//=======================================================================
Standard_Integer BRepMesh_CurveTessellator::PointsNb () const
{
  return myDiscretTool.NbPoints ();
}

//=======================================================================
//function : splitByDeflection2d
//purpose  : 
//=======================================================================
void BRepMesh_CurveTessellator::splitByDeflection2d ()
{
  const Standard_Integer aNodesNb = myDiscretTool.NbPoints ();
  if (!myDEdge->IsFree ()      &&
      myDEdge->GetSameParam () &&
      myDEdge->GetSameRange () &&
      aNodesNb > 1)
  {
    for (Standard_Integer aPCurveIt = 0; aPCurveIt < myDEdge->PCurvesNb (); ++aPCurveIt)
    {
      TopLoc_Location aLoc;
      const IMeshData::IPCurveHandle& aPCurve = myDEdge->GetPCurve(aPCurveIt);
      const TopoDS_Face&              aFace   = aPCurve->GetFace ()->GetFace ();
      const Handle (Geom_Surface)&    aSurface = BRep_Tool::Surface (aFace, aLoc);
      if (aSurface->IsInstance(STANDARD_TYPE(Geom_Plane)))
      {
        continue;
      }

      const TopoDS_Edge aCurrEdge = TopoDS::Edge(myEdge.Oriented(aPCurve->GetOrientation()));

      Standard_Real aF, aL;
      Handle (Geom2d_Curve) aCurve2d = BRep_Tool::CurveOnSurface (aCurrEdge, aFace, aF, aL);
      TColStd_Array1OfReal aParamArray (1, aNodesNb);
      for (Standard_Integer i = 1; i <= aNodesNb; ++i)
        aParamArray.SetValue (i, myDiscretTool.Parameter (i));

      for (Standard_Integer i = 1; i < aNodesNb; ++i)
        splitSegment (aSurface, aCurve2d, aParamArray (i), aParamArray (i + 1), 1);
    }
  }
}

//=======================================================================
//function : addInternalVertices
//purpose  : 
//=======================================================================
void BRepMesh_CurveTessellator::addInternalVertices ()
{
  // PTv, chl/922/G9, Take into account internal vertices
  // it is necessary for internal edges, which do not split other edges, by their vertex
  TopExp_Explorer aVertexIt (myEdge, TopAbs_VERTEX);
  for (; aVertexIt.More (); aVertexIt.Next ())
  {
    const TopoDS_Vertex& aVertex = TopoDS::Vertex (aVertexIt.Current ());
    if (aVertex.Orientation() != TopAbs_INTERNAL)
    {
      continue;
    }

    myDiscretTool.AddPoint (BRep_Tool::Pnt (aVertex),
      BRep_Tool::Parameter (aVertex, myEdge), Standard_True);
  }
}

//=======================================================================
//function : isInToleranceOfVertex
//purpose  : 
//=======================================================================
Standard_Boolean BRepMesh_CurveTessellator::isInToleranceOfVertex (
  const gp_Pnt&        thePoint,
  const TopoDS_Vertex& theVertex) const
{
  const gp_Pnt        aPoint     = BRep_Tool::Pnt(theVertex);
  const Standard_Real aTolerance = BRep_Tool::Tolerance(theVertex);

  return (thePoint.SquareDistance (aPoint) < aTolerance * aTolerance);
}

//=======================================================================
//function : Value
//purpose  : 
//=======================================================================
Standard_Boolean BRepMesh_CurveTessellator::Value (
  const Standard_Integer theIndex,
  gp_Pnt&                thePoint,
  Standard_Real&         theParameter) const
{
  thePoint     = myDiscretTool.Value     (theIndex);
  theParameter = myDiscretTool.Parameter (theIndex);

  /*if (!isInToleranceOfVertex(thePoint, myFirstVertex) &&
      !isInToleranceOfVertex(thePoint, myLastVertex))
  {*/
    if (!myCurve.IsCurveOnSurface())
    {
      return Standard_True;
    }

    // If point coordinates are out of surface range, 
    // it is necessary to re-project point.
    const Adaptor3d_CurveOnSurface& aCurve = myCurve.CurveOnSurface();
    const Handle(Adaptor3d_HSurface)& aSurface = aCurve.GetSurface();
    if (aSurface->GetType() != GeomAbs_BSplineSurface &&
        aSurface->GetType() != GeomAbs_BezierSurface  &&
        aSurface->GetType() != GeomAbs_OtherSurface)
    {
      return Standard_True;
    }

    // Let skip periodic case.
    if (aSurface->IsUPeriodic() || aSurface->IsVPeriodic())
    {
      return Standard_True;
    }

    gp_Pnt2d aUV;
    aCurve.GetCurve()->D0(theParameter, aUV);
    // Point lies within the surface range - nothing to do.
    if (aUV.X() > myFaceRangeU[0] && aUV.X() < myFaceRangeU[1] &&
        aUV.Y() > myFaceRangeV[0] && aUV.Y() < myFaceRangeV[1])
    {
      return Standard_True;
    }

    gp_Pnt aPntOnSurf;
    aSurface->D0(aUV.X(), aUV.Y(), aPntOnSurf);

    return (thePoint.SquareDistance(aPntOnSurf) < myEdgeSqTol);
  /*}

  return Standard_False;*/
}

//=======================================================================
//function : splitSegment
//purpose  : 
//=======================================================================
void BRepMesh_CurveTessellator::splitSegment (
  const Handle (Geom_Surface)& theSurf,
  const Handle (Geom2d_Curve)& theCurve2d,
  const Standard_Real          theFirst,
  const Standard_Real          theLast,
  const Standard_Integer       theNbIter)
{
  // limit iteration depth
  if (theNbIter > 10)
  {
    return;
  }

  gp_Pnt2d uvf, uvl, uvm;
  gp_Pnt   P3dF, P3dL, midP3d, midP3dFromSurf;
  Standard_Real midpar;

  if (Abs(theLast - theFirst) < 2 * Precision::PConfusion())
  {
    return;
  }

  if ((theCurve2d->FirstParameter() - theFirst > Precision::PConfusion()) ||
      (theLast - theCurve2d->LastParameter() > Precision::PConfusion()))
  {
    // E.g. test bugs moddata_3 bug30133
    return;
  }

  theCurve2d->D0 (theFirst, uvf);
  theCurve2d->D0 (theLast, uvl);

  P3dF = theSurf->Value (uvf.X (), uvf.Y ());
  P3dL = theSurf->Value (uvl.X (), uvl.Y ());

  if (P3dF.SquareDistance(P3dL) < mySquareMinSize)
  {
    return;
  }

  uvm = gp_Pnt2d ((uvf.XY () + uvl.XY ())*0.5);
  midP3dFromSurf = theSurf->Value (uvm.X (), uvm.Y ());

  gp_XYZ Vec1 = midP3dFromSurf.XYZ () - P3dF.XYZ ();
  if (Vec1.SquareModulus() < mySquareMinSize)
  {
    return;
  }

  gp_XYZ aVec = P3dL.XYZ () - P3dF.XYZ ();
  aVec.Normalize ();

  Standard_Real aModulus = Vec1.Dot (aVec);
  gp_XYZ aProj = aVec * aModulus;
  gp_XYZ aDist = Vec1 - aProj;

  if (aDist.SquareModulus() < mySquareEdgeDef)
  {
    return;
  }

  midpar = (theFirst + theLast) * 0.5;
  myCurve.D0 (midpar, midP3d);
  myDiscretTool.AddPoint (midP3d, midpar, Standard_False);

  splitSegment (theSurf, theCurve2d, theFirst, midpar, theNbIter + 1);
  splitSegment (theSurf, theCurve2d, midpar, theLast, theNbIter + 1);
}
