// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "ui/compositor_extra/shadow.h"

#include "base/test/test_discardable_memory_allocator.h"
#include "testing/gmock/include/gmock/gmock.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "ui/compositor/layer.h"
#include "ui/compositor/scoped_animation_duration_scale_mode.h"
#include "ui/gfx/geometry/insets.h"
#include "ui/gfx/shadow_util.h"
#include "ui/gfx/shadow_value.h"

namespace ui {
namespace {

using ::testing::FieldsAre;

constexpr int kElevationLarge = 24;
constexpr int kElevationSmall = 6;

// A specific elevation used for testing EvictUniquelyOwnedDetail.
constexpr int kElevationUnique = 66;

gfx::Insets InsetsForElevation(int elevation) {
  return -gfx::Insets(2 * elevation) +
         gfx::Insets::TLBR(elevation, 0, -elevation, 0);
}

gfx::Size NineboxImageSizeForElevationAndCornerRadius(int elevation,
                                                      int corner_radius) {
  auto values = gfx::ShadowValue::MakeMdShadowValues(elevation);
  gfx::Rect bounds(0, 0, 1, 1);
  bounds.Inset(-gfx::ShadowValue::GetBlurRegion(values));
  bounds.Inset(-gfx::Insets(corner_radius));
  return bounds.size();
}

// Calculates the minimum shadow content size for given elevation and corner
// radius.
gfx::Size MinContentSizeForElevationAndCornerRadius(int elevation,
                                                    int corner_radius) {
  const int dimension = 4 * elevation + 2 * corner_radius;
  return gfx::Size(dimension, dimension);
}

class ShadowTest : public testing::Test {
 public:
  ShadowTest(const ShadowTest&) = delete;
  ShadowTest& operator=(const ShadowTest&) = delete;

 protected:
  ShadowTest() {}
  ~ShadowTest() override {}

  void SetUp() override {
    base::DiscardableMemoryAllocator::SetInstance(
        &discardable_memory_allocator_);
  }

  void TearDown() override {
    base::DiscardableMemoryAllocator::SetInstance(nullptr);
  }

 private:
  base::TestDiscardableMemoryAllocator discardable_memory_allocator_;
};

// Test if the proper content bounds is calculated based on the current style.
TEST_F(ShadowTest, SetContentBounds) {
  ScopedAnimationDurationScaleMode zero_duration_mode(
      ScopedAnimationDurationScaleMode::ZERO_DURATION);
  // Verify that layer bounds are outset from content bounds.
  Shadow shadow;
  {
    shadow.Init(kElevationLarge);
    gfx::Rect content_bounds(100, 100, 300, 300);
    shadow.SetContentBounds(content_bounds);
    EXPECT_EQ(content_bounds, shadow.content_bounds());
    gfx::Rect shadow_bounds(content_bounds);
    shadow_bounds.Inset(InsetsForElevation(kElevationLarge));
    EXPECT_EQ(shadow_bounds, shadow.layer()->bounds());
  }

  {
    shadow.SetElevation(kElevationSmall);
    gfx::Rect content_bounds(100, 100, 300, 300);
    shadow.SetContentBounds(content_bounds);
    EXPECT_EQ(content_bounds, shadow.content_bounds());
    gfx::Rect shadow_bounds(content_bounds);
    shadow_bounds.Inset(InsetsForElevation(kElevationSmall));
    EXPECT_EQ(shadow_bounds, shadow.layer()->bounds());
  }
}

// Test if the shadow's layer bounds are modified, setting the same content
// bounds can reset the layer bounds.
TEST_F(ShadowTest, ResetLayerBoundsBySettingSameContentBounds) {
  Shadow shadow;
  shadow.Init(kElevationLarge);
  gfx::Rect content_bounds(100, 100, 300, 300);
  shadow.SetContentBounds(content_bounds);
  EXPECT_EQ(content_bounds, shadow.content_bounds());

  const gfx::Rect layer_bounds = shadow.layer()->bounds();

  // Change shadow's layer bounds.
  const gfx::Rect modified_bounds(200, 200, 150, 400);
  shadow.layer()->SetBounds(modified_bounds);
  EXPECT_EQ(shadow.layer()->bounds(), modified_bounds);

  // Reset layer bounds by setting the same content bounds.
  shadow.SetContentBounds(content_bounds);
  EXPECT_EQ(layer_bounds, shadow.layer()->bounds());
}

// Test that the elevation is reduced when the contents are too small to handle
// the full elevation.
TEST_F(ShadowTest, AdjustElevationForSmallContents) {
  Shadow shadow;
  shadow.Init(kElevationLarge);
  {
    gfx::Rect content_bounds(100, 100, 300, 300);
    shadow.SetContentBounds(content_bounds);
    gfx::Rect shadow_bounds(content_bounds);
    shadow_bounds.Inset(InsetsForElevation(kElevationLarge));
    EXPECT_EQ(shadow_bounds, shadow.layer()->bounds());
  }

  {
    constexpr int kWidth = 80;
    gfx::Rect content_bounds(100, 100, kWidth, 300);
    shadow.SetContentBounds(content_bounds);
    gfx::Rect shadow_bounds(content_bounds);
    shadow_bounds.Inset(InsetsForElevation((kWidth - 4) / 4));
    EXPECT_EQ(shadow_bounds, shadow.layer()->bounds());
  }

  {
    constexpr int kHeight = 80;
    gfx::Rect content_bounds(100, 100, 300, kHeight);
    shadow.SetContentBounds(content_bounds);
    gfx::Rect shadow_bounds(content_bounds);
    shadow_bounds.Inset(InsetsForElevation((kHeight - 4) / 4));
    EXPECT_EQ(shadow_bounds, shadow.layer()->bounds());
  }
}

// Test that rounded corner radius is handled correctly.
TEST_F(ShadowTest, AdjustRoundedCornerRadius) {
  Shadow shadow;
  shadow.Init(kElevationSmall);
  gfx::Rect content_bounds(100, 100, 300, 300);
  shadow.SetContentBounds(content_bounds);
  EXPECT_EQ(content_bounds, shadow.content_bounds());
  shadow.SetRoundedCornerRadius(0);
  gfx::Rect shadow_bounds(content_bounds);
  shadow_bounds.Inset(InsetsForElevation(kElevationSmall));
  EXPECT_EQ(shadow_bounds, shadow.layer()->bounds());
  EXPECT_EQ(NineboxImageSizeForElevationAndCornerRadius(6, 0),
            shadow.details_for_testing()->nine_patch_image.size());
}

// Test that the uniquely owned shadow image is evicted from the cache when new
// shadow details are created.
TEST_F(ShadowTest, EvictUniquelyOwnedDetail) {
  // Insert a new shadow with unique details which will evict existing details
  // from the cache.
  {
    Shadow shadow_new;
    shadow_new.Init(kElevationUnique);
    shadow_new.SetRoundedCornerRadius(2);

    const gfx::Size min_content_size =
        MinContentSizeForElevationAndCornerRadius(kElevationUnique, 2);
    shadow_new.SetContentBounds(gfx::Rect(min_content_size));
    // The cache size should be 1.
    EXPECT_EQ(1u, gfx::ShadowDetails::GetDetailsCacheSizeForTest());

    // Creating a shadow with the same detail won't increase the cache size.
    Shadow shadow_same;
    shadow_same.Init(kElevationUnique);
    shadow_same.SetRoundedCornerRadius(2);
    shadow_same.SetContentBounds(
        gfx::Rect(gfx::Point(10, 10), min_content_size + gfx::Size(50, 50)));
    // The cache size is unchanged.
    EXPECT_EQ(1u, gfx::ShadowDetails::GetDetailsCacheSizeForTest());

    // Creating a new uniquely owned detail will increase the cache size.
    gfx::ShadowDetails::Get(kElevationUnique, 3);
    EXPECT_EQ(2u, gfx::ShadowDetails::GetDetailsCacheSizeForTest());

    // Creating a shadow with different details will replace the uniquely owned
    // detail.
    Shadow shadow_small;
    shadow_small.Init(kElevationSmall);
    shadow_small.SetRoundedCornerRadius(2);
    shadow_small.SetContentBounds(gfx::Rect(
        MinContentSizeForElevationAndCornerRadius(kElevationSmall, 2)));
    EXPECT_EQ(2u, gfx::ShadowDetails::GetDetailsCacheSizeForTest());

    // Changing the shadow appearance will insert a new detail in the cache and
    // make the old detail uniquely owned.
    shadow_small.SetRoundedCornerRadius(3);
    EXPECT_EQ(3u, gfx::ShadowDetails::GetDetailsCacheSizeForTest());

    // Changing the shadow with another appearance will replace the uniquely
    // owned detail.
    shadow_small.SetRoundedCornerRadius(4);
    EXPECT_EQ(3u, gfx::ShadowDetails::GetDetailsCacheSizeForTest());
  }

  // After destroying the all the shadows, the cache has 3 uniquely owned
  // details.
  EXPECT_EQ(3u, gfx::ShadowDetails::GetDetailsCacheSizeForTest());

  // After inserting a new detail, the uniquely owned details will be evicted.
  Shadow shadow_large;
  shadow_large.Init(kElevationLarge);
  shadow_large.SetRoundedCornerRadius(2);
  shadow_large.SetContentBounds(
      gfx::Rect(MinContentSizeForElevationAndCornerRadius(kElevationLarge, 2)));
  // The cache size is unchanged.
  EXPECT_EQ(1u, gfx::ShadowDetails::GetDetailsCacheSizeForTest());
}

class ShadowColorTest : public ShadowTest,
                        public testing::WithParamInterface<gfx::ShadowStyle> {
 public:
  ShadowColorTest() = default;
  ShadowColorTest(const ShadowColorTest&) = delete;
  ShadowColorTest& operator=(const ShadowColorTest&) = delete;
  ~ShadowColorTest() override = default;

  static std::vector<gfx::ShadowStyle> GetTestParamValues() {
#if BUILDFLAG(IS_CHROMEOS)
    return {gfx::ShadowStyle::kMaterialDesign,
            gfx::ShadowStyle::kChromeOSSystemUI};
#else
    return {gfx::ShadowStyle::kMaterialDesign};
#endif
  }
};

INSTANTIATE_TEST_SUITE_P(
    All,
    ShadowColorTest,
    testing::ValuesIn(ShadowColorTest::GetTestParamValues()));

// Tests the shadow colors are updated when setting elevation to colors map.
TEST_P(ShadowColorTest, ElevationToColorsMap) {
  Shadow shadow;
  shadow.Init(kElevationSmall);
  shadow.SetShadowStyle(GetParam());
  // Set the content bounds which is big enough for the large elevation.
  shadow.SetContentBounds(
      gfx::Rect(MinContentSizeForElevationAndCornerRadius(kElevationLarge, 0)));

  // Cache the default colors.
  const auto& values = shadow.details_for_testing()->values;
  const SkColor default_key_color = values[0].color();
  const SkColor default_ambient_color = values[1].color();

  // Set a color map.
  const SkColor small_key_color = SkColorSetA(SK_ColorRED, 0x3d);
  const SkColor small_ambient_color = SkColorSetA(SK_ColorBLUE, 0x1a);
  const SkColor large_key_color = SkColorSetA(SK_ColorGREEN, 0x41);
  const SkColor large_ambient_color = SkColorSetA(SK_ColorYELLOW, 0x26);
  Shadow::ElevationToColorsMap color_map;
  color_map[kElevationSmall] =
      std::make_pair(small_key_color, small_ambient_color);
  color_map[kElevationLarge] =
      std::make_pair(large_key_color, large_ambient_color);
  shadow.SetElevationToColorsMap(color_map);

  // A lambda to get key and ambient shadow colors.
  auto get_colors =
      [](const ui::Shadow& shadow) -> std::pair<SkColor, SkColor> {
    const auto& values = shadow.details_for_testing()->values;
    return std::make_pair(values[0].color(), values[1].color());
  };

  // Check if shadow colors are updated.
  EXPECT_THAT(get_colors(shadow),
              FieldsAre(small_key_color, small_ambient_color));

  // Check if shadow colors are updated when the shadow changes to another
  // specified elevation.
  shadow.SetElevation(kElevationLarge);
  EXPECT_THAT(get_colors(shadow),
              FieldsAre(large_key_color, large_ambient_color));

  // Check if the shadow colors change back to default colors when the shadow
  // changes to a non-specified elevation.
  shadow.SetElevation(kElevationSmall + 1);
  EXPECT_THAT(get_colors(shadow),
              FieldsAre(default_key_color, default_ambient_color));
}

}  // namespace
}  // namespace ui