#include <Precision.hxx>
#include <TColStd_Array2OfReal.hxx>


Approx_ComputeCSurface::Approx_ComputeCSurface(
			  const Surface&                Surf,
			  const Standard_Integer        degreemin,
			  const Standard_Integer        degreemax,
			  const Standard_Real           Tolerance3d,
			  const AppParCurves_Constraint FirstCons,
			  const AppParCurves_Constraint LastUCons,
			  const AppParCurves_Constraint LastVCons,
			  const AppParCurves_Constraint LastCons,
			  const Standard_Boolean        cutting)
{
  mydegremin = degreemin;
  mydegremax = degreemax;
  mytol3d = Tolerance3d;
  myfirstUCons  = FirstCons;
  mylastUCons   = LastUCons;
  mylastVCons   = LastVCons;
  mylastCons    = LastCons;
  mycut = cutting;
  
  Perform(Surf);
}



Approx_ComputeCSurface::Approx_ComputeCSurface(
			  const Standard_Integer        degreemin,
			  const Standard_Integer        degreemax,
			  const Standard_Real           Tolerance3d,
			  const AppParCurves_Constraint FirstCons,
			  const AppParCurves_Constraint LastUCons,
			  const AppParCurves_Constraint LastVCons,
			  const AppParCurves_Constraint LastCons,
			  const Standard_Boolean        cutting)
{
  mydegremin = degreemin;
  mydegremax = degreemax;
  mytol3d = Tolerance3d;
  myfirstUCons  = FirstCons;
  mylastUCons   = LastUCons;
  mylastVCons   = LastVCons;
  mylastCons    = LastCons;
  mycut = cutting;
}



void Approx_ComputeCSurface::Perform(const Surface& Surf) 
{
  Standard_Real UFirst, ULast, VFirst, VLast;
  UFirst = SurfaceTool::FirstUParameter(Surf);
  ULast  = SurfaceTool::LastUParameter(Surf);
  VFirst = SurfaceTool::FirstVParameter(Surf);
  VLast  = SurfaceTool::LastVParameter(Surf);
  Standard_Boolean Finish = Standard_False, 
          begin = Standard_True, Ok = Standard_False;
  Standard_Real thetol3d;
  Standard_Real myfirstU = UFirst, mylastU = ULast;
  Standard_Real myfirstV = VFirst, mylastV = VLast;
  Standard_Integer i;

  TColStd_Array2OfReal Error(1, 50, 1, 50);   // pour l instant

  if (!mycut) {
    alldone = Compute(Surf, UFirst, ULast, VFirst, VLast, thetol3d);
    if (!alldone) {
      tolreached = Standard_False;
      mySurfaces.Append(TheSurface);
      Tolers3d.Append(thetol3d);
      myfirstUparam.Append(UFirst);
      mylastUparam.Append(ULast);
      myfirstVparam.Append(VFirst);
      mylastVparam.Append(VLast);
    }
  }

  else {  // gestion du decoupage:
    TColStd_SequenceOfReal TheU, TheV;
    TheU.Append(UFirst);
    TheU.Append(ULast);
    TheV.Append(VFirst);
    TheV.Append(VLast);

    while (!Finish) {
      
      Ok = Compute(Surf, myfirstU, mylastU, myfirstV, mylastV, thetol3d);
      if (Ok) {
	if (Abs(ULast-mylastU) <= Precision::PConfusion() &&
	    Abs(VLast-mylastV) <= Precision::PConfusion()) {
	  Finish = Standard_True;
	  alldone = Standard_True;
	  return;
	}
	myfirstU = mylastU;
	mylastU = ULast;
      }
      else {
	// choix du decoupage en u ou en v:
	// si debut, en u:
	if (begin) {
	  begin = Standard_False;
	  mylastU = (myfirstU + mylastU)/2.;
	  TheU.InsertAfter(1, mylastU);
	  Error.SetValue(1, 1, currenttol3d);
	}
	else {
	  Standard_Real tolu, tolv;
	  for (i = 1; i <= TheU.Length(); i++) {
	    
	  }

	}


      }
      
      
    }      

  }

}



Standard_Boolean Approx_ComputeCSurface::Compute(const Surface&      Surf,
						 const Standard_Real Ufirst,
						 const Standard_Real Ulast,
						 const Standard_Real Vfirst,
						 const Standard_Real Vlast,
						 Standard_Real&      TheTol3d) 

{
  Standard_Integer NbPoints = 12;     // 12 * 12 sur la surface.
  Standard_Integer degu, degv;
  Standard_Real Fv;

  for (degu = mydegremin; degu <= mydegremax; degu++) {
    for (degv = mydegremin; degv <= mydegremax; degv++) {
      Approx_MySLeastSquare LSQ(Surf, Ufirst, Ulast, Vfirst, Vlast,
				myfirstUCons, mylastUCons, 
				mylastVCons, mylastCons,
				degu, degv, NbPoints);
      LSQ.Error(Fv, TheTol3d);
      if (TheTol3d <= mytol3d) {
	TheSurface = LSQ.Value();
	mySurfaces.Append(TheSurface);
	tolreached = Standard_True;
	Tolers3d.Append(TheTol3d);
	currenttol3d = TheTol3d;
	myfirstUparam.Append(Ufirst);
	mylastUparam.Append(Ulast);
	myfirstVparam.Append(Vfirst);
	mylastVparam.Append(Vlast);
	return Standard_True;
      }
      
      if (degu == mydegremax && degv == mydegremax) {
	TheSurface = LSQ.Value();
	tolreached = Standard_False;
	currenttol3d = TheTol3d;
      }
    }
  }
  return Standard_False;
}



Standard_Real Approx_ComputeCSurface::Error(const Standard_Integer Index)const
{
  return Tolers3d.Value(Index);
}
				   


Handle(Geom_BezierSurface) Approx_ComputeCSurface::Value(const Standard_Integer Index)const
{
  return Handle(Geom_BezierSurface)::DownCast(mySurfaces.Value(Index));
}


Standard_Integer Approx_ComputeCSurface::NbSurfaces() const
{
  return mySurfaces.Length();
}


void Approx_ComputeCSurface::Parameters(const Standard_Integer Index,
					Standard_Real& firstU,
					Standard_Real& lastU,
					Standard_Real& firstV,
					Standard_Real& lastV)const
{
  firstU = myfirstUparam.Value(Index);
  lastU = mylastUparam.Value(Index);
  firstV = myfirstVparam.Value(Index);
  lastV = mylastVparam.Value(Index);
}


Standard_Boolean Approx_ComputeCSurface::IsToleranceReached() const
{
  return tolreached;
}

Standard_Boolean Approx_ComputeCSurface::IsAllApproximated() const
{
  return alldone;
}


void Approx_ComputeCSurface::SetDegrees(const Standard_Integer degreemin,
					const Standard_Integer degreemax)
{
  mydegremin = degreemin;
  mydegremax = degreemax;
}



void Approx_ComputeCSurface::SetTolerance(const Standard_Real Tolerance3d)
{
  mytol3d = Tolerance3d;
}