// Copyright (c) 2008  GeometryFactory Sarl (France).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org).
//
// $URL: https://github.com/CGAL/cgal/blob/v6.2-beta1/Periodic_4_hyperbolic_triangulation_2/demo/Periodic_4_hyperbolic_triangulation_2/include/internal/Qt/VoronoiGraphicsItem.h $
// $Id: demo/Periodic_4_hyperbolic_triangulation_2/include/internal/Qt/VoronoiGraphicsItem.h 431cfb5357d $
// SPDX-License-Identifier: GPL-3.0-or-later OR LicenseRef-Commercial
//
// Author(s)     : Andreas Fabri <Andreas.Fabri@geometryfactory.com>
//                 Laurent Rineau <Laurent.Rineau@geometryfactory.com>

#ifndef CGAL_QT_VORONOI_GRAPHICS_ITEM_H
#define CGAL_QT_VORONOI_GRAPHICS_ITEM_H

#include <CGAL/Qt/GraphicsItem.h>
#include <CGAL/Qt/PainterOstream.h>
#include <CGAL/Qt/utility.h>

#include <QGraphicsScene>
#include <QGraphicsSceneMouseEvent>
#include <QPainter>
#include <QStyleOption>

#include <CGAL/intersection_2.h>

class QGraphicsSceneMouseEvent;


namespace CGAL {
namespace Qt {

template <typename DT>
class VoronoiGraphicsItem : public GraphicsItem
{
public:
  VoronoiGraphicsItem(DT  * dt_);


  QRectF
  boundingRect() const;

  void
  paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget);

  void
  modelChanged();

  const QPen& edgesPen() const
  {
    return edges_pen;
  }

  void setEdgesPen(const QPen& pen)
  {
    edges_pen = pen;
  }

private:

  void updateCCenters() {
    cc.clear();
    for(typename DT::Face_iterator it = dt->faces_begin(); it != dt->faces_end(); it++) {
      cc[it] = dt->geom_traits().construct_inexact_hyperbolic_circumcenter_2_object()(*it);
    }
  }

  typedef typename DT::Hyperbolic_Voronoi_point                                   Voronoi_point;
  typedef typename DT::Face_handle                                                Face_handle;
  typedef typename DT::Point                                                      Point;

  DT * dt;
  QPen edges_pen;
  std::map<Face_handle, Voronoi_point> cc;   // to hold the circumcenters of all the faces
};



template <typename DT>
VoronoiGraphicsItem<DT>::VoronoiGraphicsItem(DT * dt_)
  :  dt(dt_)
{
  setZValue(3);
  updateCCenters();
}

template <typename DT>
QRectF
VoronoiGraphicsItem<DT>::boundingRect() const
{
  QRectF rect = CGAL::Qt::viewportsBbox(scene());
  return rect;
}


template <typename DT>
void
VoronoiGraphicsItem<DT>::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget * /*w*/)
{
  QRectF rect = option->exposedRect;
  PainterOstream<typename DT::Geom_traits> pos(painter, rect);

  painter->setPen(edgesPen());

  // delete
  QPen temp = painter->pen();
  QPen old = temp;
  temp.setWidthF(0.01);
  painter->setPen(temp);

  for(typename DT::Face_iterator fit = dt->faces_begin(); fit != dt->faces_end(); fit++) {
    for(int i=0; i<3; ++i) {
      Point p1 = cc[fit];
      Point p2 = dt->geom_traits().construct_hyperbolic_point_2_object()(cc[fit->neighbor(i)], dt->neighbor_translation(fit, i));
      typename DT::Hyperbolic_segment s =  dt->geom_traits().construct_hyperbolic_segment_2_object()(p1, p2);
      pos << s;
    }
  }

  painter->setPen(old);
}


template <typename T>
void
VoronoiGraphicsItem<T>::modelChanged()
{
  updateCCenters();
  update();
}

} // namespace Qt
} // namespace CGAL

#endif // CGAL_QT_VORONOI_GRAPHICS_ITEM_H
