// Copyright (c) 1995-1999 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.

// init. de MinRad et MaxRad (PRO15604), JCT 09/10/98

#include <ElCLib.hxx>
#include <GccAna_Circ2d3Tan.hxx>
#include <GccAna_CircLin2dBisec.hxx>
#include <GccAna_LinPnt2dBisec.hxx>
#include <GccEnt_BadQualifier.hxx>
#include <GccEnt_QualifiedCirc.hxx>
#include <GccEnt_QualifiedLin.hxx>
#include <GccInt_BParab.hxx>
#include <GccInt_IType.hxx>
#include <gp_Circ2d.hxx>
#include <gp_Dir2d.hxx>
#include <gp_Lin2d.hxx>
#include <gp_Pnt2d.hxx>
#include <IntAna2d_AnaIntersection.hxx>
#include <IntAna2d_Conic.hxx>
#include <IntAna2d_IntPoint.hxx>
#include <TColStd_Array1OfReal.hxx>

//===========================================================================
//   Creation of a circle tangent to a circle, a straight line and a point. +
//===========================================================================
GccAna_Circ2d3Tan::GccAna_Circ2d3Tan(const GccEnt_QualifiedCirc& Qualified1,
                                     const GccEnt_QualifiedLin&  Qualified2,
                                     const gp_Pnt2d&             Point3,
                                     const Standard_Real         Tolerance)
    :

      //=========================================================================
      //   Initialization of fields.                                           +
      //=========================================================================

      cirsol(1, 4),
      qualifier1(1, 4),
      qualifier2(1, 4),
      qualifier3(1, 4),
      TheSame1(1, 4),
      TheSame2(1, 4),
      TheSame3(1, 4),
      pnttg1sol(1, 4),
      pnttg2sol(1, 4),
      pnttg3sol(1, 4),
      par1sol(1, 4),
      par2sol(1, 4),
      par3sol(1, 4),
      pararg1(1, 4),
      pararg2(1, 4),
      pararg3(1, 4)
{

  gp_Dir2d      dirx(1.0, 0.0);
  Standard_Real Tol    = Abs(Tolerance);
  Standard_Real MaxRad = 1e10, MinRad = 1e-6;
  WellDone = Standard_False;
  NbrSol   = 0;
  if (!(Qualified1.IsEnclosed() || Qualified1.IsEnclosing() || Qualified1.IsOutside()
        || Qualified1.IsUnqualified())
      || !(Qualified2.IsEnclosed() || Qualified2.IsOutside() || Qualified2.IsUnqualified()))
  {
    throw GccEnt_BadQualifier();
    return;
  }

  //=========================================================================
  //   Processing.                                                          +
  //=========================================================================

  gp_Circ2d     C1(Qualified1.Qualified());
  gp_Lin2d      L2(Qualified2.Qualified());
  Standard_Real R1 = C1.Radius();
  gp_Pnt2d      center1(C1.Location());
  gp_Pnt2d      origin2(L2.Location());
  gp_Dir2d      dir2(L2.Direction());
  gp_Dir2d      normL2(-dir2.Y(), dir2.X());

  TColStd_Array1OfReal  Radius(1, 2);
  GccAna_CircLin2dBisec Bis1(C1, L2);
  GccAna_LinPnt2dBisec  Bis2(L2, Point3);
  if (Bis1.IsDone() && Bis2.IsDone())
  {
    Standard_Integer nbsolution1 = Bis1.NbSolutions();
    for (Standard_Integer i = 1; i <= nbsolution1; i++)
    {
      Handle(GccInt_Bisec)     Sol1 = Bis1.ThisSolution(i);
      Handle(GccInt_Bisec)     Sol2 = Bis2.ThisSolution();
      GccInt_IType             typ1 = Sol1->ArcType();
      GccInt_IType             typ2 = Sol2->ArcType();
      IntAna2d_AnaIntersection Intp;
      if (typ1 == GccInt_Lin)
      {
        if (typ2 == GccInt_Lin)
        {
          Intp.Perform(Sol1->Line(), Sol2->Line());
        }
        else if (typ2 == GccInt_Par)
        {
          Intp.Perform(Sol1->Line(), IntAna2d_Conic(Sol2->Parabola()));
        }
      }
      else if (typ1 == GccInt_Par)
      {
        if (typ2 == GccInt_Lin)
        {
          Intp.Perform(Sol2->Line(), IntAna2d_Conic(Sol1->Parabola()));
        }
        else if (typ2 == GccInt_Par)
        {
          Intp.Perform(Sol1->Parabola(), IntAna2d_Conic(Sol2->Parabola()));
        }
      }
      if (Intp.IsDone())
      {
        if (!Intp.IsEmpty())
        {
          for (Standard_Integer j = 1; j <= Intp.NbPoints(); j++)
          {
            gp_Pnt2d         Center(Intp.Point(j).Value());
            Standard_Real    dist1  = Center.Distance(C1.Location());
            Standard_Real    dist2  = L2.Distance(Center);
            Standard_Real    dist3  = Center.Distance(Point3);
            Standard_Integer nbsol1 = 0;
            Standard_Integer nbsol3 = 0;
            Standard_Boolean ok     = Standard_False;
            if (Qualified1.IsEnclosed())
            {
              if (dist1 - R1 < Tolerance)
              {
                Radius(1) = Abs(R1 - dist1);
                nbsol1    = 1;
                ok        = Standard_True;
              }
            }
            else if (Qualified1.IsOutside())
            {
              if (R1 - dist1 < Tolerance)
              {
                Radius(1) = Abs(R1 - dist1);
                nbsol1    = 1;
                ok        = Standard_True;
              }
            }
            else if (Qualified1.IsEnclosing())
            {
              ok        = Standard_True;
              nbsol1    = 1;
              Radius(1) = Abs(R1 - dist1);
            }
            else if (Qualified1.IsUnqualified())
            {
              ok        = Standard_True;
              nbsol1    = 2;
              Radius(1) = Abs(R1 - dist1);
              Radius(2) = R1 + dist1;
            }
            if (Qualified2.IsEnclosed() && ok)
            {
              if ((((L2.Location().X() - Center.X()) * (-L2.Direction().Y()))
                   + ((L2.Location().Y() - Center.Y()) * (L2.Direction().X())))
                  <= 0)
              {
                for (Standard_Integer ii = 1; ii <= nbsol1; ii++)
                {
                  if (Abs(dist2 - Radius(ii)) < Tol)
                  {
                    ok        = Standard_True;
                    Radius(1) = Radius(ii);
                  }
                }
              }
            }
            else if (Qualified2.IsOutside() && ok)
            {
              if ((((L2.Location().X() - Center.X()) * (-L2.Direction().Y()))
                   + ((L2.Location().Y() - Center.Y()) * (L2.Direction().X())))
                  >= 0)
              {
                for (Standard_Integer ii = 1; ii <= nbsol1; ii++)
                {
                  if (Abs(dist2 - Radius(ii)) < Tol)
                  {
                    ok        = Standard_True;
                    Radius(1) = Radius(ii);
                  }
                }
              }
            }
            else if (Qualified2.IsUnqualified() && ok)
            {
              for (Standard_Integer ii = 1; ii <= nbsol1; ii++)
              {
                if (Abs(dist2 - Radius(ii)) < Tol)
                {
                  ok        = Standard_True;
                  Radius(1) = Radius(ii);
                }
              }
            }
            if (Abs(dist3 - Radius(1)) <= Tol && ok)
            {
              ok     = Standard_True;
              nbsol3 = 1;
            }
            if (ok)
            {
              for (Standard_Integer k = 1; k <= nbsol3; k++)
              {
                if (NbrSol == 4)
                  break;
                // pop : if the radius is too great - no creation
                if (Radius(k) > MaxRad)
                  break;
                if (Abs(Radius(k)) < MinRad)
                  break;

                NbrSol++;
                cirsol(NbrSol) = gp_Circ2d(gp_Ax2d(Center, dirx), Radius(k));
                //               ==========================================================
                Standard_Real distcc1 = Center.Distance(center1);
                if (!Qualified1.IsUnqualified())
                {
                  qualifier1(NbrSol) = Qualified1.Qualifier();
                }
                else if (Abs(distcc1 + Radius(k) - R1) < Tol)
                {
                  qualifier1(NbrSol) = GccEnt_enclosed;
                }
                else if (Abs(distcc1 - R1 - Radius(k)) < Tol)
                {
                  qualifier1(NbrSol) = GccEnt_outside;
                }
                else
                {
                  qualifier1(NbrSol) = GccEnt_enclosing;
                }
                gp_Dir2d dc2(origin2.XY() - Center.XY());
                if (!Qualified2.IsUnqualified())
                {
                  qualifier2(NbrSol) = Qualified2.Qualifier();
                }
                else if (dc2.Dot(normL2) > 0.0)
                {
                  qualifier2(NbrSol) = GccEnt_outside;
                }
                else
                {
                  qualifier2(NbrSol) = GccEnt_enclosed;
                }
                qualifier3(NbrSol) = GccEnt_noqualifier;
                if (Center.Distance(C1.Location()) <= Tolerance && Abs(Radius(k) - R1) <= Tolerance)
                {
                  TheSame1(NbrSol) = 1;
                }
                else
                {
                  TheSame1(NbrSol) = 0;
                  //  modified by NIZHNY-EAP Mon Nov  1 13:48:21 1999 ___BEGIN___
                  //		   gp_Dir2d dc(C1.Location().XY()-Center.XY());
                  gp_Dir2d dc(Center.XY() - C1.Location().XY());
                  //  modified by NIZHNY-EAP Mon Nov  1 13:48:55 1999 ___END___
                  pnttg1sol(NbrSol) = gp_Pnt2d(Center.XY() + Radius(k) * dc.XY());
                  par1sol(NbrSol)   = ElCLib::Parameter(cirsol(NbrSol), pnttg1sol(NbrSol));
                  pararg1(NbrSol)   = ElCLib::Parameter(C1, pnttg1sol(NbrSol));
                }
                TheSame2(NbrSol) = 0;
                TheSame3(NbrSol) = 0;
                gp_Dir2d      dc(L2.Location().XY() - Center.XY());
                Standard_Real sign = dc.Dot(gp_Dir2d(-L2.Direction().Y(), L2.Direction().X()));
                dc                = gp_Dir2d(sign * gp_XY(-L2.Direction().Y(), L2.Direction().X()));
                pnttg2sol(NbrSol) = gp_Pnt2d(Center.XY() + Radius(k) * dc.XY());
                par2sol(NbrSol)   = ElCLib::Parameter(cirsol(NbrSol), pnttg2sol(NbrSol));
                pararg2(NbrSol)   = ElCLib::Parameter(L2, pnttg2sol(NbrSol));
                pnttg3sol(NbrSol) = Point3;
                par3sol(NbrSol)   = ElCLib::Parameter(cirsol(NbrSol), pnttg3sol(NbrSol));
                pararg3(NbrSol)   = 0.;
              }
            }
          }
        }
        WellDone = Standard_True;
      }
      if (NbrSol == 4)
        break;
    }
  }
}