// ======================================================================
//
// Copyright (c) 2000 The CGAL Consortium
//
// This software and related documentation is part of an INTERNAL release
// of the Computational Geometry Algorithms Library (CGAL). It is not
// intended for general use.
//
// ----------------------------------------------------------------------
//
// release       :
// release_date  :
//
// file          : include/CGAL/Cartesian/Circle_2.C
// revision      : $Revision$
// revision_date : $Date$
// author(s)     : Andreas Fabri, Herve Bronnimann
// coordinator   : INRIA Sophia-Antipolis (Mariette.Yvinec@sophia.inria.fr)
//
// ======================================================================

#ifndef CGAL_CARTESIAN_CIRCLE_2_C
#define CGAL_CARTESIAN_CIRCLE_2_C

#include <CGAL/Cartesian/constructions_on_points_2.h>
#include <CGAL/Cartesian/constructions_on_circles_2.h>
#include <CGAL/Cartesian/distance_computations_2.h>
#include <CGAL/Cartesian/predicates_on_points_2.h>

#ifndef CGAL_CARTESIAN_REDEFINE_NAMES_2_H
#define CGAL_CTAG
#endif

#ifdef CGAL_CFG_TYPENAME_BUG
#define typename
#endif

CGAL_BEGIN_NAMESPACE

template < class R >
CGAL_KERNEL_CTOR_INLINE
CircleC2<R CGAL_CTAG>::CircleC2()
{
  new ( static_cast< void*>(ptr)) Circle_repC2<R>();
}

template < class R >
CGAL_KERNEL_CTOR_INLINE
CircleC2<R CGAL_CTAG>::CircleC2(const CircleC2<R CGAL_CTAG> &c)
  : Handle_for< Circle_repC2<R> > (c)
{}

template < class R >
CGAL_KERNEL_CTOR_INLINE
CircleC2<R CGAL_CTAG>::
CircleC2(const typename CircleC2<R CGAL_CTAG>::Point_2 &center,
         const typename CircleC2<R CGAL_CTAG>::FT &squared_radius,
         const Orientation &orient)
{
  CGAL_kernel_precondition( ( squared_radius >= FT(0) ) &&
                            ( orient    != COLLINEAR) );

  new ( static_cast< void*>(ptr)) Circle_repC2<R>(center, 
						  squared_radius, 
						  orient);
}

template < class R >
CGAL_KERNEL_CTOR_INLINE
CircleC2<R CGAL_CTAG>::
CircleC2(const typename CircleC2<R CGAL_CTAG>::Point_2 &center,
         const Orientation &orient)
{
  CGAL_kernel_precondition( orient != COLLINEAR );

  new ( static_cast< void*>(ptr)) Circle_repC2<R>(center, FT(0), orient);
}

template < class R >
CGAL_KERNEL_CTOR_MEDIUM_INLINE
CircleC2<R CGAL_CTAG>::
CircleC2(const typename CircleC2<R CGAL_CTAG>::Point_2 &p,
         const typename CircleC2<R CGAL_CTAG>::Point_2 &q,
         const Orientation &orient)
{
  CGAL_kernel_precondition( orient != COLLINEAR);

  if ( p != q) {
    Point_2 center = midpoint(p,q);
    FT      squared_radius = squared_distance(p,center);

    new ( static_cast< void*>(ptr)) Circle_repC2<R>(center, 
						     squared_radius, 
						     orient);
  } else
    new ( static_cast< void*>(ptr)) Circle_repC2<R>(p, FT(0), orient);
}

template < class R >
CGAL_KERNEL_CTOR_MEDIUM_INLINE
CircleC2<R CGAL_CTAG>::
CircleC2(const typename CircleC2<R CGAL_CTAG>::Point_2 &p,
         const typename CircleC2<R CGAL_CTAG>::Point_2 &q,
         const typename CircleC2<R CGAL_CTAG>::Point_2 &r)
{
  Orientation orient = CGAL::orientation(p,q,r);
  CGAL_kernel_precondition( orient != COLLINEAR);

  Point_2 center = circumcenter(p,q,r);
  FT      squared_radius = squared_distance(p,center);

  new ( static_cast< void*>(ptr)) Circle_repC2<R>(center, 
						  squared_radius, 
						  orient);
}

template < class R >
inline
CircleC2<R CGAL_CTAG>::~CircleC2()
{}

template < class R >
CGAL_KERNEL_INLINE
bool
CircleC2<R CGAL_CTAG>::operator==(const CircleC2<R CGAL_CTAG> &c) const
{
  return center() == c.center() &&
         squared_radius() == c.squared_radius() &&
         orientation() == c.orientation();
}

template < class R >
inline
bool
CircleC2<R CGAL_CTAG>::operator!=(const CircleC2<R CGAL_CTAG> &c) const
{
  return !(*this == c);
}

template < class R >
inline
CircleC2<R CGAL_CTAG>::Point_2
CircleC2<R CGAL_CTAG>::center() const
{
 return ptr->center;
}

template < class R >
inline
CircleC2<R CGAL_CTAG>::FT
CircleC2<R CGAL_CTAG>::squared_radius() const
{
 return ptr->squared_radius;
}

template < class R >
inline
Orientation
CircleC2<R CGAL_CTAG>::orientation() const
{
 return ptr->orient;
}

template < class R >
CGAL_KERNEL_MEDIUM_INLINE
Oriented_side
CircleC2<R CGAL_CTAG>::
oriented_side(const typename CircleC2<R CGAL_CTAG>::Point_2 &p) const
{
  return Oriented_side(bounded_side(p) * orientation());
}

template < class R >
CGAL_KERNEL_INLINE
Bounded_side
CircleC2<R CGAL_CTAG>::
bounded_side(const typename CircleC2<R CGAL_CTAG>::Point_2 &p) const
{
  return Bounded_side(CGAL_NTS compare(squared_radius(),
                                       squared_distance(center(),p)));
}

template < class R >
inline
bool
CircleC2<R CGAL_CTAG>::
has_on_boundary(const typename CircleC2<R CGAL_CTAG>::Point_2 &p) const
{
  return squared_distance(center(),p) == squared_radius();
}

template < class R >
CGAL_KERNEL_INLINE
bool
CircleC2<R CGAL_CTAG>::
has_on_negative_side(const typename CircleC2<R CGAL_CTAG>::Point_2 &p) const
{
  if (orientation() == COUNTERCLOCKWISE)
    return has_on_unbounded_side(p);
  return has_on_bounded_side(p);
}

template < class R >
CGAL_KERNEL_INLINE
bool
CircleC2<R CGAL_CTAG>::
has_on_positive_side(const typename CircleC2<R CGAL_CTAG>::Point_2 &p) const
{
  if (orientation() == COUNTERCLOCKWISE)
    return has_on_bounded_side(p);
  return has_on_unbounded_side(p);
}

template < class R >
inline
bool
CircleC2<R CGAL_CTAG>::
has_on_bounded_side(const typename CircleC2<R CGAL_CTAG>::Point_2 &p) const
{
  return squared_distance(center(),p) < squared_radius();
}

template < class R >
inline
bool
CircleC2<R CGAL_CTAG>::
has_on_unbounded_side(const typename CircleC2<R CGAL_CTAG>::Point_2 &p) const
{
  return squared_distance(center(),p) > squared_radius();
}

template < class R >
inline
bool
CircleC2<R CGAL_CTAG>::is_degenerate() const
{
  return CGAL_NTS is_zero(squared_radius());
}

template < class R >
inline
CircleC2<R CGAL_CTAG>
CircleC2<R CGAL_CTAG>::opposite() const
{
  return CircleC2<R CGAL_CTAG>(center(),
                               squared_radius(),
                               CGAL::opposite(orientation()) );
}

template < class R >
CGAL_KERNEL_INLINE
Bbox_2
CircleC2<R CGAL_CTAG>::bbox() const
{
  // Robustness problems.
  double cx = CGAL::to_double(center().x());
  double cy = CGAL::to_double(center().y());
  double radius = CGAL::sqrt(CGAL::to_double(squared_radius()));

  return Bbox_2(cx - radius, cy - radius, cx + radius, cy + radius);
}

template < class R >
CGAL_KERNEL_INLINE
CircleC2<R CGAL_CTAG>
CircleC2<R CGAL_CTAG>::orthogonal_transform
  (const typename CircleC2<R CGAL_CTAG>::Aff_transformation_2 &t) const
{
  Vector_2 vec(FT(1), FT(0) );   // unit vector
  vec = vec.transform(t);             // transformed
  FT sq_scale = vec.squared_length();       // squared scaling factor

  return CircleC2<R CGAL_CTAG>(t.transform(center()),
                               sq_scale * squared_radius(),
                               t.is_even() ? orientation()
                                           : CGAL::opposite(orientation()));
}

/*
template < class R >
inline
EllipseC2<CircleC2<R CGAL_CTAG>::FT>
CircleC2<R CGAL_CTAG>::
transform(const Aff_transformationC2<CircleC2<R CGAL_CTAG>::FT> &t) const
{
  return CircleC2<R CGAL_CTAG>(t.transform(center()),
                               squared_radius(),
                               orientation());
}
*/

#ifndef CGAL_NO_OSTREAM_INSERT_CIRCLEC2
template < class R >
CGAL_KERNEL_INLINE
std::ostream &
operator<<(std::ostream &os, const CircleC2<R CGAL_CTAG> &c)
{
    switch(os.iword(IO::mode)) {
    case IO::ASCII :
        os << c.center() << ' ' << c.squared_radius() << ' '
           << (int)c.orientation();
        break;
    case IO::BINARY :
        os << c.center();
        write(os, c.squared_radius());
        write(os, (int)c.orientation());
        break;
    default:
        os << "CircleC2(" << c.center() <<  ", " << c.squared_radius() ;
        switch (c.orientation()) {
        case CLOCKWISE:
            os << ", clockwise)";
            break;
        case COUNTERCLOCKWISE:
            os << ", counterclockwise)";
            break;
        default:
            os << ", collinear)";
            break;
        }
        break;
    }
    return os;
}
#endif // CGAL_NO_OSTREAM_INSERT_CIRCLEC2

#ifndef CGAL_NO_ISTREAM_EXTRACT_CIRCLEC2
template < class R >
CGAL_KERNEL_INLINE
std::istream&
operator>>(std::istream &is, CircleC2<R CGAL_CTAG> &c)
{
    typename CircleC2<R CGAL_CTAG>::Point_2 center;
    typename CircleC2<R CGAL_CTAG>::FT squared_radius;
    int o;
    switch(is.iword(IO::mode)) {
    case IO::ASCII :
        is >> center >> squared_radius >> o;
        break;
    case IO::BINARY :
        is >> center;
        read(is, squared_radius);
        is >> o;
        break;
    default:
        std::cerr << "" << std::endl;
        std::cerr << "Stream must be in ascii or binary mode" << std::endl;
        break;
    }
    c = CircleC2<R CGAL_CTAG>(center, squared_radius, (Orientation)o);
    return is;
}
#endif // CGAL_NO_ISTREAM_EXTRACT_CIRCLEC2

CGAL_END_NAMESPACE

#ifdef CGAL_CFG_TYPENAME_BUG
#undef typename
#endif

#endif // CGAL_CARTESIAN_CIRCLE_2_C