// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_GFX_GEOMETRY_RECT_F_H_
#define UI_GFX_GEOMETRY_RECT_F_H_

#include <iosfwd>
#include <string>

#include "ui/gfx/geometry/point_f.h"
#include "ui/gfx/geometry/size_f.h"
#include "ui/gfx/geometry/vector2d_f.h"

namespace gfx {

class InsetsF;

// A floating version of gfx::Rect.
class GFX_EXPORT RectF {
 public:
  RectF() {}
  RectF(float width, float height) : size_(width, height) {}
  RectF(float x, float y, float width, float height)
      : origin_(x, y), size_(width, height) {}
  explicit RectF(const SizeF& size) : size_(size) {}
  RectF(const PointF& origin, const SizeF& size)
      : origin_(origin), size_(size) {}

  ~RectF() {}

  float x() const { return origin_.x(); }
  void set_x(float x) { origin_.set_x(x); }

  float y() const { return origin_.y(); }
  void set_y(float y) { origin_.set_y(y); }

  float width() const { return size_.width(); }
  void set_width(float width) { size_.set_width(width); }

  float height() const { return size_.height(); }
  void set_height(float height) { size_.set_height(height); }

  const PointF& origin() const { return origin_; }
  void set_origin(const PointF& origin) { origin_ = origin; }

  const SizeF& size() const { return size_; }
  void set_size(const SizeF& size) { size_ = size; }

  float right() const { return x() + width(); }
  float bottom() const { return y() + height(); }

  PointF top_right() const { return PointF(right(), y()); }
  PointF bottom_left() const { return PointF(x(), bottom()); }
  PointF bottom_right() const { return PointF(right(), bottom()); }

  Vector2dF OffsetFromOrigin() const { return Vector2dF(x(), y()); }

  void SetRect(float x, float y, float width, float height) {
    origin_.SetPoint(x, y);
    size_.SetSize(width, height);
  }

  // Shrink the rectangle by a horizontal and vertical distance on all sides.
  void Inset(float horizontal, float vertical) {
    Inset(horizontal, vertical, horizontal, vertical);
  }

  // Shrink the rectangle by the given insets.
  void Inset(const InsetsF& insets);

  // Shrink the rectangle by the specified amount on each side.
  void Inset(float left, float top, float right, float bottom);

  // Move the rectangle by a horizontal and vertical distance.
  void Offset(float horizontal, float vertical);
  void Offset(const Vector2dF& distance) { Offset(distance.x(), distance.y()); }
  void operator+=(const Vector2dF& offset);
  void operator-=(const Vector2dF& offset);

  InsetsF InsetsFrom(const RectF& inner) const;

  // Returns true if the area of the rectangle is zero.
  bool IsEmpty() const { return size_.IsEmpty(); }

  // A rect is less than another rect if its origin is less than
  // the other rect's origin. If the origins are equal, then the
  // shortest rect is less than the other. If the origin and the
  // height are equal, then the narrowest rect is less than.
  // This comparison is required to use Rects in sets, or sorted
  // vectors.
  bool operator<(const RectF& other) const;

  // Returns true if the point identified by point_x and point_y falls inside
  // this rectangle.  The point (x, y) is inside the rectangle, but the
  // point (x + width, y + height) is not.
  bool Contains(float point_x, float point_y) const;

  // Returns true if the specified point is contained by this rectangle.
  bool Contains(const PointF& point) const {
    return Contains(point.x(), point.y());
  }

  // Returns true if this rectangle contains the specified rectangle.
  bool Contains(const RectF& rect) const;

  // Returns true if this rectangle intersects the specified rectangle.
  // An empty rectangle doesn't intersect any rectangle.
  bool Intersects(const RectF& rect) const;

  // Computes the intersection of this rectangle with the given rectangle.
  void Intersect(const RectF& rect);

  // Computes the union of this rectangle with the given rectangle.  The union
  // is the smallest rectangle containing both rectangles.
  void Union(const RectF& rect);

  // Computes the rectangle resulting from subtracting |rect| from |*this|,
  // i.e. the bounding rect of |Region(*this) - Region(rect)|.
  void Subtract(const RectF& rect);

  // Fits as much of the receiving rectangle into the supplied rectangle as
  // possible, becoming the result. For example, if the receiver had
  // a x-location of 2 and a width of 4, and the supplied rectangle had
  // an x-location of 0 with a width of 5, the returned rectangle would have
  // an x-location of 1 with a width of 4.
  void AdjustToFit(const RectF& rect);

  // Returns the center of this rectangle.
  PointF CenterPoint() const;

  // Becomes a rectangle that has the same center point but with a size capped
  // at given |size|.
  void ClampToCenteredSize(const SizeF& size);

  // Splits |this| in two halves, |left_half| and |right_half|.
  void SplitVertically(RectF* left_half, RectF* right_half) const;

  // Returns true if this rectangle shares an entire edge (i.e., same width or
  // same height) with the given rectangle, and the rectangles do not overlap.
  bool SharesEdgeWith(const RectF& rect) const;

  // Returns the manhattan distance from the rect to the point. If the point is
  // inside the rect, returns 0.
  float ManhattanDistanceToPoint(const PointF& point) const;

  // Returns the manhattan distance between the contents of this rect and the
  // contents of the given rect. That is, if the intersection of the two rects
  // is non-empty then the function returns 0. If the rects share a side, it
  // returns the smallest non-zero value appropriate for float.
  float ManhattanInternalDistance(const RectF& rect) const;

  // Scales the rectangle by |scale|.
  void Scale(float scale) {
    Scale(scale, scale);
  }

  void Scale(float x_scale, float y_scale) {
    set_origin(ScalePoint(origin(), x_scale, y_scale));
    set_size(ScaleSize(size(), x_scale, y_scale));
  }

  // This method reports if the RectF can be safely converted to an integer
  // Rect. When it is false, some dimension of the RectF is outside the bounds
  // of what an integer can represent, and converting it to a Rect will require
  // clamping.
  bool IsExpressibleAsRect() const;

  std::string ToString() const;

 private:
  PointF origin_;
  SizeF size_;
};

inline bool operator==(const RectF& lhs, const RectF& rhs) {
  return lhs.origin() == rhs.origin() && lhs.size() == rhs.size();
}

inline bool operator!=(const RectF& lhs, const RectF& rhs) {
  return !(lhs == rhs);
}

inline RectF operator+(const RectF& lhs, const Vector2dF& rhs) {
  return RectF(lhs.x() + rhs.x(), lhs.y() + rhs.y(),
      lhs.width(), lhs.height());
}

inline RectF operator-(const RectF& lhs, const Vector2dF& rhs) {
  return RectF(lhs.x() - rhs.x(), lhs.y() - rhs.y(),
      lhs.width(), lhs.height());
}

inline RectF operator+(const Vector2dF& lhs, const RectF& rhs) {
  return rhs + lhs;
}

GFX_EXPORT RectF IntersectRects(const RectF& a, const RectF& b);
GFX_EXPORT RectF UnionRects(const RectF& a, const RectF& b);
GFX_EXPORT RectF SubtractRects(const RectF& a, const RectF& b);

inline RectF ScaleRect(const RectF& r, float x_scale, float y_scale) {
  return RectF(r.x() * x_scale, r.y() * y_scale,
       r.width() * x_scale, r.height() * y_scale);
}

inline RectF ScaleRect(const RectF& r, float scale) {
  return ScaleRect(r, scale, scale);
}

// Constructs a rectangle with |p1| and |p2| as opposite corners.
//
// This could also be thought of as "the smallest rect that contains both
// points", except that we consider points on the right/bottom edges of the
// rect to be outside the rect.  So technically one or both points will not be
// contained within the rect, because they will appear on one of these edges.
GFX_EXPORT RectF BoundingRect(const PointF& p1, const PointF& p2);

// This is declared here for use in gtest-based unit tests but is defined in
// the gfx_test_support target. Depend on that to use this in your unit test.
// This should not be used in production code - call ToString() instead.
void PrintTo(const RectF& rect, ::std::ostream* os);

}  // namespace gfx

#endif  // UI_GFX_GEOMETRY_RECT_F_H_