/**
 * File: rect_fwd.h
 *
 * Author: Andrew Stein (andrew)
 * Created: 5/10/2014
 *
 * Description: Defines a templated class for storing 2D rectangles according to 
 *              their upper left corner and width + height.
 *
 *  NOTE: This header "forward declares" templated definitions.
 *        To get the implementations, you must include rect.h.
 *
 * Copyright: Anki, Inc. 2014
 *
 **/

#ifndef _ANKICORETECH_COMMON_RECT_H_
#define _ANKICORETECH_COMMON_RECT_H_

static_assert(ANKICORETECH_USE_OPENCV, "Rectangle implementation requires OpenCV");
#include "opencv2/core.hpp"

#include "coretech/common/shared/math/point.h"

namespace Anki {
  
// A class for storing axis-aligned 2D rectangles.
// (x,y) is upper left corner
// bottom/right boundaries are non inclusive (like OpenCV)
// so x in [rectangle.x, rectangle.x + rectangle.width) are inside, and
//    y in [rectangle.y, rectangle.y + rectangle.height) are inside
// Note the inclusive "[" vs. the non-inclusive ")".
template<typename T>
class Rectangle
: private cv::Rect_<T> // private inheritance from cv::Rect
{
public:
  Rectangle();
  Rectangle(T x, T y, T width, T height);
  Rectangle(const Point2<T>& corner1, const Point2<T>& corner2);
  
  // Construct bounding boxes:
  template<typename T_other>
  explicit Rectangle(const std::vector<Point<2,T_other> >& points);
  
  template<size_t NumPoints, typename T_other>
  explicit Rectangle(const std::array<Point<2,T_other>,NumPoints>& points);
  
  T Area() const { return width*height; }
  
  // (x,y) is the top left
  inline T GetX()      const;
  inline T GetY()      const;
  inline T GetWidth()  const;
  inline T GetHeight() const;

  // Get x+width or y+height
  inline T GetXmax()   const;
  inline T GetYmax()   const;

  // Get x+width/2 or y+height/2
  inline T GetXmid()   const;
  inline T GetYmid()   const;

  inline Point<2,T> GetTopLeft() const;
  inline Point<2,T> GetTopRight() const;
  inline Point<2,T> GetBottomLeft() const;
  inline Point<2,T> GetBottomRight() const;
  
  inline Point<2,T> GetMidPoint() const;
  
  Rectangle<T> Intersect(const Rectangle<T>& other) const;
  
  bool Contains(const Point<2,T>& point) const;
  
  // Compute Intersection-over-Union overlap score (on interval [0,1])
  f32 ComputeOverlapScore(const Rectangle<T>& other) const;
  
  // Return new rectangle scaled about the center of the current one
  Rectangle<T> Scale(const f32 scaleFactor) const;
  
  // OpenCV converters/accessors
  Rectangle(const cv::Rect_<T>& cvRect);
  const cv::Rect_<T>& get_CvRect_() const;
  cv::Rect_<T>& get_CvRect_();
  
protected:
  
  template<class PointContainer>
  void InitFromPointContainer(const PointContainer& points);
  
  using cv::Rect_<T>::x;
  using cv::Rect_<T>::y;
  using cv::Rect_<T>::width;
  using cv::Rect_<T>::height;
  
}; // class Rectangle
  
} // namespace Anki

#endif // _ANKICORETECH_COMMON_RECT_H_