// Created on: 1992-01-02
// Created by: Remi GILET
// Copyright (c) 1992-1999 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.

#include <ElCLib.hxx>
#include <GccAna_Circ2d2TanOn.hxx>
#include <GccAna_CircLin2dBisec.hxx>
#include <GccEnt_BadQualifier.hxx>
#include <GccEnt_QualifiedCirc.hxx>
#include <GccEnt_QualifiedLin.hxx>
#include <GccInt_BCirc.hxx>
#include <GccInt_IType.hxx>
#include <gp_Ax2d.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>

//=========================================================================
//   Creation of a circle tangent to Circle C1 and a straight line L2.    +
//                        centered on a straight line.                    +
//  We start by making difference between cases that we are going to      +
//  process separately.                                                   +
//  In general case:                                                      +
//  ====================                                                  +
//  We calculate bissectrices to C1 and L2 that give us                   +
//  all possible locations of centers of all circles tangent to C1 and L2 +
//  We intersect these bissectrices with straight line OnLine which gives +
//  us points among which we'll choose the solutions.                     +
//  The choices are made basing on Qualifiers of C1 and L2.               +
//=========================================================================
GccAna_Circ2d2TanOn::GccAna_Circ2d2TanOn(const GccEnt_QualifiedCirc& Qualified1,
                                         const GccEnt_QualifiedLin&  Qualified2,
                                         const gp_Lin2d&             OnLine,
                                         const double                Tolerance)
    : cirsol(1, 4),
      qualifier1(1, 4),
      qualifier2(1, 4),
      TheSame1(1, 4),
      TheSame2(1, 4),
      pnttg1sol(1, 4),
      pnttg2sol(1, 4),
      pntcen(1, 4),
      par1sol(1, 4),
      par2sol(1, 4),
      pararg1(1, 4),
      pararg2(1, 4),
      parcen3(1, 4)
{

  TheSame1.Init(0);
  TheSame2.Init(0);
  WellDone = false;
  NbrSol   = 0;
  if (!(Qualified1.IsEnclosed() || Qualified1.IsEnclosing() || Qualified1.IsOutside()
        || Qualified1.IsUnqualified())
      || !(Qualified2.IsEnclosed() || Qualified2.IsOutside() || Qualified2.IsUnqualified()))
  {
    throw GccEnt_BadQualifier();
    return;
  }
  double    Tol    = std::abs(Tolerance);
  double    Radius = 0;
  bool      ok     = false;
  gp_Dir2d  dirx(gp_Dir2d::D::X);
  gp_Circ2d C1 = Qualified1.Qualified();
  gp_Lin2d  L2 = Qualified2.Qualified();
  double    R1 = C1.Radius();
  gp_Pnt2d  center1(C1.Location());
  gp_Pnt2d  origin2(L2.Location());
  gp_Dir2d  dirL2(L2.Direction());
  gp_Dir2d  normL2(-dirL2.Y(), dirL2.X());

  //=========================================================================
  //   Processing of limit cases.                                          +
  //=========================================================================

  double   distcl = OnLine.Distance(center1);
  gp_Pnt2d pinterm(center1.XY() + distcl * gp_XY(-OnLine.Direction().Y(), OnLine.Direction().X()));
  if (OnLine.Distance(pinterm) > Tolerance)
  {
    pinterm =
      gp_Pnt2d(center1.XY() + distcl * gp_XY(-OnLine.Direction().Y(), OnLine.Direction().X()));
  }
  double dist2 = L2.Distance(pinterm);
  if (Qualified1.IsEnclosed() || Qualified1.IsOutside())
  {
    if (std::abs(distcl - R1 - dist2) <= Tol)
    {
      ok = true;
    }
  }
  else if (Qualified1.IsEnclosing())
  {
    if (std::abs(dist2 - distcl - R1) <= Tol)
    {
      ok = true;
    }
  }
  else if (Qualified1.IsUnqualified())
  {
    ok = true;
  }
  else
  {
    throw GccEnt_BadQualifier();
    return;
  }
  if (ok)
  {
    if (Qualified2.IsOutside())
    {
      gp_Pnt2d pbid(pinterm.XY() + dist2 * gp_XY(-dirL2.Y(), dirL2.X()));
      if (L2.Distance(pbid) <= Tol)
      {
        WellDone = true;
      }
    }
    else if (Qualified2.IsEnclosed())
    {
      gp_Pnt2d pbid(pinterm.XY() - dist2 * gp_XY(-dirL2.Y(), dirL2.X()));
      if (L2.Distance(pbid) <= Tol)
      {
        WellDone = true;
      }
    }
    else if (Qualified2.IsUnqualified())
    {
      WellDone = false;
    }
    else
    {
      throw GccEnt_BadQualifier();
      return;
    }
  }
  if (WellDone)
  {
    NbrSol++;
    cirsol(NbrSol) = gp_Circ2d(gp_Ax2d(pinterm, dirx), dist2);
    //   =======================================================
    gp_Dir2d dc1(center1.XY() - pinterm.XY());
    gp_Dir2d dc2(origin2.XY() - pinterm.XY());
    double   distcc1 = pinterm.Distance(center1);
    if (!Qualified1.IsUnqualified())
    {
      qualifier1(NbrSol) = Qualified1.Qualifier();
    }
    else if (std::abs(distcc1 + dist2 - R1) < Tol)
    {
      qualifier1(NbrSol) = GccEnt_enclosed;
    }
    else if (std::abs(distcc1 - R1 - dist2) < Tol)
    {
      qualifier1(NbrSol) = GccEnt_outside;
    }
    else
    {
      qualifier1(NbrSol) = GccEnt_enclosing;
    }
    if (!Qualified2.IsUnqualified())
    {
      qualifier2(NbrSol) = Qualified2.Qualifier();
    }
    else if (dc2.Dot(normL2) > 0.0)
    {
      qualifier2(NbrSol) = GccEnt_outside;
    }
    else
    {
      qualifier2(NbrSol) = GccEnt_enclosed;
    }

    double sign       = dc2.Dot(gp_Dir2d(-dirL2.Y(), dirL2.X()));
    dc2               = gp_Dir2d(sign * gp_XY(-dirL2.Y(), dirL2.X()));
    pnttg1sol(NbrSol) = gp_Pnt2d(pinterm.XY() + dist2 * dc1.XY());
    pnttg2sol(NbrSol) = gp_Pnt2d(pinterm.XY() + dist2 * dc2.XY());
    par1sol(NbrSol)   = ElCLib::Parameter(cirsol(NbrSol), pnttg1sol(NbrSol));
    pararg1(NbrSol)   = ElCLib::Parameter(C1, pnttg1sol(NbrSol));
    par2sol(NbrSol)   = ElCLib::Parameter(cirsol(NbrSol), pnttg2sol(NbrSol));
    pararg2(NbrSol)   = ElCLib::Parameter(L2, pnttg2sol(NbrSol));
    pntcen(NbrSol)    = cirsol(NbrSol).Location();
    parcen3(NbrSol)   = ElCLib::Parameter(OnLine, pntcen(NbrSol));
    return;
  }

  //=========================================================================
  //   General case.                                                        +
  //=========================================================================

  GccAna_CircLin2dBisec Bis(C1, L2);
  if (Bis.IsDone())
  {
    int nbsolution = Bis.NbSolutions();
    for (int i = 1; i <= nbsolution; i++)
    {
      occ::handle<GccInt_Bisec> Sol  = Bis.ThisSolution(i);
      GccInt_IType              type = Sol->ArcType();
      IntAna2d_AnaIntersection  Intp;
      if (type == GccInt_Lin)
      {
        Intp.Perform(OnLine, Sol->Line());
      }
      else if (type == GccInt_Par)
      {
        Intp.Perform(OnLine, IntAna2d_Conic(Sol->Parabola()));
      }
      if (Intp.IsDone())
      {
        if (!Intp.IsEmpty())
        {
          for (int j = 1; j <= Intp.NbPoints(); j++)
          {
            gp_Pnt2d Center(Intp.Point(j).Value());
            double   dist1 = Center.Distance(center1);
            dist2          = L2.Distance(Center);
            //	     int nbsol = 1;
            ok = false;
            if (Qualified1.IsEnclosed())
            {
              if (dist1 - R1 < Tolerance)
              {
                if (std::abs(std::abs(R1 - dist1) - dist2) < Tolerance)
                {
                  ok = true;
                }
              }
            }
            else if (Qualified1.IsOutside())
            {
              if (R1 - dist1 < Tolerance)
              {
                if (std::abs(std::abs(R1 - dist1) - dist2) < Tolerance)
                {
                  ok = true;
                }
              }
            }
            else if (Qualified1.IsEnclosing() || Qualified1.IsUnqualified())
            {
              ok = true;
            }
            if (Qualified2.IsEnclosed() && ok)
            {
              if ((((origin2.X() - Center.X()) * (-dirL2.Y()))
                   + ((origin2.Y() - Center.Y()) * (dirL2.X())))
                  <= 0)
              {
                ok     = true;
                Radius = dist2;
              }
            }
            else if (Qualified2.IsOutside() && ok)
            {
              if ((((origin2.X() - Center.X()) * (-dirL2.Y()))
                   + ((origin2.Y() - Center.Y()) * (dirL2.X())))
                  >= 0)
              {
                ok     = true;
                Radius = dist2;
              }
            }
            else if (Qualified2.IsUnqualified() && ok)
            {
              ok     = true;
              Radius = dist2;
            }
            if (ok)
            {
              NbrSol++;
              cirsol(NbrSol) = gp_Circ2d(gp_Ax2d(Center, dirx), Radius);
              //             =======================================================
              gp_Dir2d dc1(center1.XY() - Center.XY());
              gp_Dir2d dc2(origin2.XY() - Center.XY());
              double   distcc1 = Center.Distance(center1);
              if (!Qualified1.IsUnqualified())
              {
                qualifier1(NbrSol) = Qualified1.Qualifier();
              }
              else if (std::abs(distcc1 + Radius - R1) < Tol)
              {
                qualifier1(NbrSol) = GccEnt_enclosed;
              }
              else if (std::abs(distcc1 - R1 - Radius) < Tol)
              {
                qualifier1(NbrSol) = GccEnt_outside;
              }
              else
              {
                qualifier1(NbrSol) = GccEnt_enclosing;
              }
              if (!Qualified2.IsUnqualified())
              {
                qualifier2(NbrSol) = Qualified2.Qualifier();
              }
              else if (dc2.Dot(normL2) > 0.0)
              {
                qualifier2(NbrSol) = GccEnt_outside;
              }
              else
              {
                qualifier2(NbrSol) = GccEnt_enclosed;
              }
              if (Center.Distance(center1) <= Tolerance
                  && std::abs(Radius - C1.Radius()) <= Tolerance)
              {
                TheSame1(NbrSol) = 1;
              }
              else
              {
                TheSame1(NbrSol)  = 0;
                pnttg1sol(NbrSol) = gp_Pnt2d(Center.XY() + Radius * dc1.XY());
                par1sol(NbrSol)   = ElCLib::Parameter(cirsol(NbrSol), pnttg1sol(NbrSol));
                pararg1(NbrSol)   = ElCLib::Parameter(C1, pnttg1sol(NbrSol));
              }
              TheSame2(NbrSol)  = 0;
              double sign       = dc2.Dot(gp_Dir2d(-dirL2.Y(), dirL2.X()));
              dc2               = gp_Dir2d(sign * gp_XY(-dirL2.Y(), dirL2.X()));
              pnttg2sol(NbrSol) = gp_Pnt2d(Center.XY() + Radius * dc2.XY());
              par2sol(NbrSol)   = ElCLib::Parameter(cirsol(NbrSol), pnttg2sol(NbrSol));
              pararg2(NbrSol)   = ElCLib::Parameter(L2, pnttg2sol(NbrSol));
              pntcen(NbrSol)    = Center;
              parcen3(NbrSol)   = ElCLib::Parameter(OnLine, pntcen(NbrSol));
            }
          }
        }
        WellDone = true;
      }
    }
  }
}
