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// 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_SIZE_F_H_
#define UI_GFX_GEOMETRY_SIZE_F_H_

#include <iosfwd>
#include <string>

#include "base/compiler_specific.h"
#include "base/gtest_prod_util.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gfx/gfx_export.h"

namespace gfx {

FORWARD_DECLARE_TEST(SizeTest, TrivialDimensionTests);
FORWARD_DECLARE_TEST(SizeTest, ClampsToZero);
FORWARD_DECLARE_TEST(SizeTest, ConsistentClamping);

// A floating version of gfx::Size.
class GFX_EXPORT SizeF {
 public:
  constexpr SizeF() : width_(0.f), height_(0.f) {}
  constexpr SizeF(float width, float height)
      : width_(clamp(width)), height_(clamp(height)) {}

  constexpr explicit SizeF(const Size& size)
      : SizeF(static_cast<float>(size.width()),
              static_cast<float>(size.height())) {}

  constexpr float width() const { return width_; }
  constexpr float height() const { return height_; }

  void set_width(float width) { width_ = clamp(width); }
  void set_height(float height) { height_ = clamp(height); }

  float GetArea() const;

  void SetSize(float width, float height) {
    set_width(width);
    set_height(height);
  }

  void Enlarge(float grow_width, float grow_height);

  void SetToMin(const SizeF& other);
  void SetToMax(const SizeF& other);

  bool IsEmpty() const { return !width() || !height(); }

  void Scale(float scale) {
    Scale(scale, scale);
  }

  void Scale(float x_scale, float y_scale) {
    SetSize(width() * x_scale, height() * y_scale);
  }

  std::string ToString() const;

 private:
  FRIEND_TEST_ALL_PREFIXES(SizeTest, TrivialDimensionTests);
  FRIEND_TEST_ALL_PREFIXES(SizeTest, ClampsToZero);
  FRIEND_TEST_ALL_PREFIXES(SizeTest, ConsistentClamping);

  static constexpr float kTrivial = 8.f * std::numeric_limits<float>::epsilon();

  static constexpr float clamp(float f) { return f > kTrivial ? f : 0.f; }

  float width_;
  float height_;
};

inline bool operator==(const SizeF& lhs, const SizeF& rhs) {
  return lhs.width() == rhs.width() && lhs.height() == rhs.height();
}

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

GFX_EXPORT SizeF ScaleSize(const SizeF& p, float x_scale, float y_scale);

inline SizeF ScaleSize(const SizeF& p, float scale) {
  return ScaleSize(p, scale, scale);
}

// This is declared here for use in gtest-based unit tests but is defined in
// the //ui/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 SizeF& size, ::std::ostream* os);

}  // namespace gfx

#endif  // UI_GFX_GEOMETRY_SIZE_F_H_