ui/base/native_theme/native_theme_android.cc

// 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.

#include "ui/base/native_theme/native_theme_android.h"

#include <limits>

#include "base/basictypes.h"
#include "base/logging.h"
#include "base/memory/scoped_ptr.h"
#include "grit/ui_resources.h"
#include "third_party/skia/include/effects/SkGradientShader.h"
#include "ui/base/layout.h"
#include "ui/base/resource/resource_bundle.h"
#include "ui/gfx/canvas.h"
#include "ui/gfx/color_utils.h"
#include "ui/gfx/rect.h"
#include "ui/gfx/size.h"

namespace ui {

const unsigned int kButtonLength = 14;
const unsigned int kScrollbarWidth = 15;
const unsigned int kThumbInactiveColor = 0xeaeaea;
const unsigned int kTrackColor= 0xd3d3d3;

// These are the default dimensions of radio buttons and checkboxes.
const int kCheckboxAndRadioWidth = 13;
const int kCheckboxAndRadioHeight = 13;

// These sizes match the sizes in Chromium Win.
const int kSliderThumbWidth = 11;
const int kSliderThumbHeight = 21;

const SkColor kSliderTrackBackgroundColor = SkColorSetRGB(0xe3, 0xdd, 0xd8);
const SkColor kSliderThumbLightGrey = SkColorSetRGB(0xf4, 0xf2, 0xef);
const SkColor kSliderThumbDarkGrey = SkColorSetRGB(0xea, 0xe5, 0xe0);
const SkColor kSliderThumbBorderDarkGrey = SkColorSetRGB(0x9d, 0x96, 0x8e);

// Get lightness adjusted color.
SkColor BrightenColor(const color_utils::HSL& hsl,
                      SkAlpha alpha,
                      double lightness_amount) {
  color_utils::HSL adjusted = hsl;
  adjusted.l += lightness_amount;
  if (adjusted.l > 1.0)
    adjusted.l = 1.0;
  if (adjusted.l < 0.0)
    adjusted.l = 0.0;

  return color_utils::HSLToSkColor(adjusted, alpha);
}

// static
const NativeTheme* NativeTheme::instance() {
  return NativeThemeAndroid::instance();
}

// static
const NativeThemeAndroid* NativeThemeAndroid::instance() {
  CR_DEFINE_STATIC_LOCAL(NativeThemeAndroid, s_native_theme, ());
  return &s_native_theme;
}

gfx::Size NativeThemeAndroid::GetPartSize(Part part,
                                          State state,
                                          const ExtraParams& extra) const {
  switch (part) {
    case kScrollbarDownArrow:
    case kScrollbarUpArrow:
      return gfx::Size(kScrollbarWidth, kButtonLength);
    case kScrollbarLeftArrow:
    case kScrollbarRightArrow:
      return gfx::Size(kButtonLength, kScrollbarWidth);
    case kCheckbox:
    case kRadio:
      return gfx::Size(kCheckboxAndRadioWidth, kCheckboxAndRadioHeight);
    case kSliderThumb:
      // These sizes match the sizes in Chromium Win.
      return gfx::Size(kSliderThumbWidth, kSliderThumbHeight);
    case kInnerSpinButton:
      return gfx::Size(kScrollbarWidth, 0);
    case kPushButton:
    case kTextField:
    case kMenuList:
    case kSliderTrack:
    case kProgressBar:
      return gfx::Size();  // No default size.
    default:
      NOTREACHED();
  }
  return gfx::Size();
}

void NativeThemeAndroid::Paint(SkCanvas* canvas,
                               Part part,
                               State state,
                               const gfx::Rect& rect,
                               const ExtraParams& extra) const {
  switch (part) {
    case kScrollbarDownArrow:
    case kScrollbarUpArrow:
    case kScrollbarLeftArrow:
    case kScrollbarRightArrow:
      PaintArrowButton(canvas, rect, part, state);
      break;
    case kCheckbox:
      PaintCheckbox(canvas, state, rect, extra.button);
      break;
    case kRadio:
      PaintRadio(canvas, state, rect, extra.button);
      break;
    case kPushButton:
      PaintButton(canvas, state, rect, extra.button);
      break;
    case kTextField:
      PaintTextField(canvas, state, rect, extra.text_field);
      break;
    case kMenuList:
      PaintMenuList(canvas, state, rect, extra.menu_list);
      break;
    case kSliderTrack:
      PaintSliderTrack(canvas, state, rect, extra.slider);
      break;
    case kSliderThumb:
      PaintSliderThumb(canvas, state, rect, extra.slider);
      break;
    case kInnerSpinButton:
      PaintInnerSpinButton(canvas, state, rect, extra.inner_spin);
      break;
    case kProgressBar:
      PaintProgressBar(canvas, state, rect, extra.progress_bar);
      break;
    default:
      NOTREACHED();
  }
}

SkColor NativeThemeAndroid::GetSystemColor(ColorId color_id) const {
  NOTIMPLEMENTED();
  return SK_ColorBLACK;
}

NativeThemeAndroid::NativeThemeAndroid() {
}

NativeThemeAndroid::~NativeThemeAndroid() {
}

void NativeThemeAndroid::PaintArrowButton(SkCanvas* canvas,
                                          const gfx::Rect& rect,
                                          Part direction,
                                          State state) const {
  int widthMiddle;
  int lengthMiddle;
  SkPaint paint;
  if (direction == kScrollbarUpArrow || direction == kScrollbarDownArrow) {
    widthMiddle = rect.width() / 2 + 1;
    lengthMiddle = rect.height() / 2 + 1;
  } else {
    lengthMiddle = rect.width() / 2 + 1;
    widthMiddle = rect.height() / 2 + 1;
  }

  // Calculate button color.
  SkScalar trackHSV[3];
  SkColorToHSV(kTrackColor, trackHSV);
  SkColor buttonColor = SaturateAndBrighten(trackHSV, 0, 0.2);
  SkColor backgroundColor = buttonColor;
  if (state == kPressed) {
    SkScalar buttonHSV[3];
    SkColorToHSV(buttonColor, buttonHSV);
    buttonColor = SaturateAndBrighten(buttonHSV, 0, -0.1);
  } else if (state == kHovered) {
    SkScalar buttonHSV[3];
    SkColorToHSV(buttonColor, buttonHSV);
    buttonColor = SaturateAndBrighten(buttonHSV, 0, 0.05);
  }

  SkIRect skrect;
  skrect.set(rect.x(), rect.y(), rect.x() + rect.width(), rect.y()
      + rect.height());
  // Paint the background (the area visible behind the rounded corners).
  paint.setColor(backgroundColor);
  canvas->drawIRect(skrect, paint);

  // Paint the button's outline and fill the middle
  SkPath outline;
  switch (direction) {
    case kScrollbarUpArrow:
      outline.moveTo(rect.x() + 0.5, rect.y() + rect.height() + 0.5);
      outline.rLineTo(0, -(rect.height() - 2));
      outline.rLineTo(2, -2);
      outline.rLineTo(rect.width() - 5, 0);
      outline.rLineTo(2, 2);
      outline.rLineTo(0, rect.height() - 2);
      break;
    case kScrollbarDownArrow:
      outline.moveTo(rect.x() + 0.5, rect.y() - 0.5);
      outline.rLineTo(0, rect.height() - 2);
      outline.rLineTo(2, 2);
      outline.rLineTo(rect.width() - 5, 0);
      outline.rLineTo(2, -2);
      outline.rLineTo(0, -(rect.height() - 2));
      break;
    case kScrollbarRightArrow:
      outline.moveTo(rect.x() - 0.5, rect.y() + 0.5);
      outline.rLineTo(rect.width() - 2, 0);
      outline.rLineTo(2, 2);
      outline.rLineTo(0, rect.height() - 5);
      outline.rLineTo(-2, 2);
      outline.rLineTo(-(rect.width() - 2), 0);
      break;
    case kScrollbarLeftArrow:
      outline.moveTo(rect.x() + rect.width() + 0.5, rect.y() + 0.5);
      outline.rLineTo(-(rect.width() - 2), 0);
      outline.rLineTo(-2, 2);
      outline.rLineTo(0, rect.height() - 5);
      outline.rLineTo(2, 2);
      outline.rLineTo(rect.width() - 2, 0);
      break;
    default:
      break;
  }
  outline.close();

  paint.setStyle(SkPaint::kFill_Style);
  paint.setColor(buttonColor);
  canvas->drawPath(outline, paint);

  paint.setAntiAlias(true);
  paint.setStyle(SkPaint::kStroke_Style);
  SkScalar thumbHSV[3];
  SkColorToHSV(kThumbInactiveColor, thumbHSV);
  paint.setColor(OutlineColor(trackHSV, thumbHSV));
  canvas->drawPath(outline, paint);

  // If the button is disabled or read-only, the arrow is drawn with the
  // outline color.
  if (state != kDisabled)
    paint.setColor(SK_ColorBLACK);

  paint.setAntiAlias(false);
  paint.setStyle(SkPaint::kFill_Style);

  SkPath path;
  // The constants in this block of code are hand-tailored to produce good
  // looking arrows without anti-aliasing.
  switch (direction) {
    case kScrollbarUpArrow:
      path.moveTo(rect.x() + widthMiddle - 4, rect.y() + lengthMiddle + 2);
      path.rLineTo(7, 0);
      path.rLineTo(-4, -4);
      break;
    case kScrollbarDownArrow:
      path.moveTo(rect.x() + widthMiddle - 4, rect.y() + lengthMiddle - 3);
      path.rLineTo(7, 0);
      path.rLineTo(-4, 4);
      break;
    case kScrollbarRightArrow:
      path.moveTo(rect.x() + lengthMiddle - 3, rect.y() + widthMiddle - 4);
      path.rLineTo(0, 7);
      path.rLineTo(4, -4);
      break;
    case kScrollbarLeftArrow:
      path.moveTo(rect.x() + lengthMiddle + 1, rect.y() + widthMiddle - 5);
      path.rLineTo(0, 9);
      path.rLineTo(-4, -4);
      break;
    default:
      break;
  }
  path.close();

  canvas->drawPath(path, paint);
}

void NativeThemeAndroid::PaintCheckbox(SkCanvas* canvas,
                                       State state,
                                       const gfx::Rect& rect,
                                       const ButtonExtraParams& button) const {
  ResourceBundle& rb = ResourceBundle::GetSharedInstance();
  gfx::ImageSkia* image = NULL;
  if (button.indeterminate) {
    image = state == kDisabled ?
        rb.GetImageSkiaNamed(IDR_CHECKBOX_DISABLED_INDETERMINATE) :
        rb.GetImageSkiaNamed(IDR_CHECKBOX_INDETERMINATE);
  } else if (button.checked) {
    image = state == kDisabled ?
        rb.GetImageSkiaNamed(IDR_CHECKBOX_DISABLED_ON) :
        rb.GetImageSkiaNamed(IDR_CHECKBOX_ON);
  } else {
    image = state == kDisabled ?
        rb.GetImageSkiaNamed(IDR_CHECKBOX_DISABLED_OFF) :
        rb.GetImageSkiaNamed(IDR_CHECKBOX_OFF);
  }

  gfx::Rect bounds = rect.Center(gfx::Size(image->width(), image->height()));
  DrawImageInt(canvas, *image, 0, 0, image->width(), image->height(),
      bounds.x(), bounds.y(), bounds.width(), bounds.height());
}

void NativeThemeAndroid::PaintRadio(SkCanvas* canvas,
                                    State state,
                                    const gfx::Rect& rect,
                                    const ButtonExtraParams& button) const {
  ResourceBundle& rb = ResourceBundle::GetSharedInstance();
  gfx::ImageSkia* image = NULL;
  if (state == kDisabled) {
    image = button.checked ?
        rb.GetImageSkiaNamed(IDR_RADIO_DISABLED_ON) :
        rb.GetImageSkiaNamed(IDR_RADIO_DISABLED_OFF);
  } else {
    image = button.checked ?
        rb.GetImageSkiaNamed(IDR_RADIO_ON) :
        rb.GetImageSkiaNamed(IDR_RADIO_OFF);
  }

  gfx::Rect bounds = rect.Center(gfx::Size(image->width(), image->height()));
  DrawImageInt(canvas, *image, 0, 0, image->width(), image->height(),
      bounds.x(), bounds.y(), bounds.width(), bounds.height());
}

void NativeThemeAndroid::PaintButton(SkCanvas* canvas,
                                     State state,
                                     const gfx::Rect& rect,
                                     const ButtonExtraParams& button) const {
  SkPaint paint;
  SkRect skrect;
  int kRight = rect.right();
  int kBottom = rect.bottom();
  SkColor base_color = button.background_color;

  color_utils::HSL base_hsl;
  color_utils::SkColorToHSL(base_color, &base_hsl);

  // Our standard gradient is from 0xdd to 0xf8. This is the amount of
  // increased luminance between those values.
  SkColor light_color(BrightenColor(base_hsl, SkColorGetA(base_color), 0.105));

  // If the button is too small, fallback to drawing a single, solid color
  if (rect.width() < 5 || rect.height() < 5) {
    paint.setColor(base_color);
    skrect.set(rect.x(), rect.y(), kRight, kBottom);
    canvas->drawRect(skrect, paint);
    return;
  }

  if (button.has_border) {
    int kBorderAlpha = state == kHovered ? 0x80 : 0x55;
    paint.setARGB(kBorderAlpha, 0, 0, 0);
    canvas->drawLine(rect.x() + 1, rect.y(), kRight - 1, rect.y(), paint);
    canvas->drawLine(kRight - 1, rect.y() + 1, kRight - 1, kBottom - 1, paint);
    canvas->drawLine(rect.x() + 1, kBottom - 1, kRight - 1, kBottom - 1, paint);
    canvas->drawLine(rect.x(), rect.y() + 1, rect.x(), kBottom - 1, paint);
  }

  paint.setColor(SK_ColorBLACK);
  int kLightEnd = state == kPressed ? 1 : 0;
  int kDarkEnd = !kLightEnd;
  SkPoint gradient_bounds[2];
  gradient_bounds[kLightEnd].iset(rect.x(), rect.y());
  gradient_bounds[kDarkEnd].iset(rect.x(), kBottom - 1);
  SkColor colors[2];
  colors[0] = light_color;
  colors[1] = base_color;

  SkShader* shader = SkGradientShader::CreateLinear(
      gradient_bounds, colors, NULL, 2, SkShader::kClamp_TileMode, NULL);
  paint.setStyle(SkPaint::kFill_Style);
  paint.setShader(shader);
  shader->unref();

  if (button.has_border) {
    skrect.set(rect.x() + 1, rect.y() + 1, kRight - 1, kBottom - 1);
  } else {
    skrect.set(rect.x(), rect.y(), kRight, kBottom);
  }
  canvas->drawRect(skrect, paint);
  paint.setShader(NULL);

  if (button.has_border) {
    paint.setColor(BrightenColor(base_hsl, SkColorGetA(base_color), -0.0588));
    canvas->drawPoint(rect.x() + 1, rect.y() + 1, paint);
    canvas->drawPoint(kRight - 2, rect.y() + 1, paint);
    canvas->drawPoint(rect.x() + 1, kBottom - 2, paint);
    canvas->drawPoint(kRight - 2, kBottom - 2, paint);
  }
}

void NativeThemeAndroid::PaintTextField(
    SkCanvas* canvas,
    State state,
    const gfx::Rect& rect,
    const TextFieldExtraParams& text) const {
  // The following drawing code simulates the user-agent css border for
  // text area and text input so that we do not break layout tests. Once we
  // have decided the desired looks, we should update the code here and
  // the layout test expectations.
  SkRect bounds;
  bounds.set(rect.x(), rect.y(), rect.right() - 1, rect.bottom() - 1);

  SkPaint fill_paint;
  fill_paint.setStyle(SkPaint::kFill_Style);
  fill_paint.setColor(text.background_color);
  canvas->drawRect(bounds, fill_paint);

  if (text.is_text_area) {
    // Draw text area border: 1px solid black
    SkPaint stroke_paint;
    fill_paint.setStyle(SkPaint::kStroke_Style);
    fill_paint.setColor(SK_ColorBLACK);
    canvas->drawRect(bounds, fill_paint);
  } else {
    // Draw text input and listbox inset border
    //   Text Input: 2px inset #eee
    //   Listbox: 1px inset #808080
    SkColor kLightColor = text.is_listbox ?
        SkColorSetRGB(0x80, 0x80, 0x80) : SkColorSetRGB(0xee, 0xee, 0xee);
    SkColor kDarkColor = text.is_listbox ?
        SkColorSetRGB(0x2c, 0x2c, 0x2c) : SkColorSetRGB(0x9a, 0x9a, 0x9a);
    int kBorderWidth = text.is_listbox ? 1 : 2;

    SkPaint dark_paint;
    dark_paint.setAntiAlias(true);
    dark_paint.setStyle(SkPaint::kFill_Style);
    dark_paint.setColor(kDarkColor);

    SkPaint light_paint;
    light_paint.setAntiAlias(true);
    light_paint.setStyle(SkPaint::kFill_Style);
    light_paint.setColor(kLightColor);

    int left = rect.x();
    int top = rect.y();
    int right = rect.right();
    int bottom = rect.bottom();

    SkPath path;
    path.incReserve(4);

    // Top
    path.moveTo(SkIntToScalar(left), SkIntToScalar(top));
    path.lineTo(SkIntToScalar(left + kBorderWidth),
                SkIntToScalar(top + kBorderWidth));
    path.lineTo(SkIntToScalar(right - kBorderWidth),
                SkIntToScalar(top + kBorderWidth));
    path.lineTo(SkIntToScalar(right), SkIntToScalar(top));
    canvas->drawPath(path, dark_paint);

    // Bottom
    path.reset();
    path.moveTo(SkIntToScalar(left + kBorderWidth),
                SkIntToScalar(bottom - kBorderWidth));
    path.lineTo(SkIntToScalar(left), SkIntToScalar(bottom));
    path.lineTo(SkIntToScalar(right), SkIntToScalar(bottom));
    path.lineTo(SkIntToScalar(right - kBorderWidth),
                SkIntToScalar(bottom - kBorderWidth));
    canvas->drawPath(path, light_paint);

    // Left
    path.reset();
    path.moveTo(SkIntToScalar(left), SkIntToScalar(top));
    path.lineTo(SkIntToScalar(left), SkIntToScalar(bottom));
    path.lineTo(SkIntToScalar(left + kBorderWidth),
                SkIntToScalar(bottom - kBorderWidth));
    path.lineTo(SkIntToScalar(left + kBorderWidth),
                SkIntToScalar(top + kBorderWidth));
    canvas->drawPath(path, dark_paint);

    // Right
    path.reset();
    path.moveTo(SkIntToScalar(right - kBorderWidth),
                SkIntToScalar(top + kBorderWidth));
    path.lineTo(SkIntToScalar(right - kBorderWidth), SkIntToScalar(bottom));
    path.lineTo(SkIntToScalar(right), SkIntToScalar(bottom));
    path.lineTo(SkIntToScalar(right), SkIntToScalar(top));
    canvas->drawPath(path, light_paint);
  }
}

void NativeThemeAndroid::PaintMenuList(
    SkCanvas* canvas,
    State state,
    const gfx::Rect& rect,
    const MenuListExtraParams& menu_list) const {
  // If a border radius is specified, we let the WebCore paint the background
  // and the border of the control.
  if (!menu_list.has_border_radius) {
    ButtonExtraParams button = { 0 };
    button.background_color = menu_list.background_color;
    button.has_border = menu_list.has_border;
    PaintButton(canvas, state, rect, button);
  }

  SkPaint paint;
  paint.setColor(SK_ColorBLACK);
  paint.setAntiAlias(true);
  paint.setStyle(SkPaint::kFill_Style);

  SkPath path;
  path.moveTo(menu_list.arrow_x, menu_list.arrow_y - 3);
  path.rLineTo(6, 0);
  path.rLineTo(-3, 6);
  path.close();
  canvas->drawPath(path, paint);
}

void NativeThemeAndroid::PaintSliderTrack(
    SkCanvas* canvas,
    State state,
    const gfx::Rect& rect,
    const SliderExtraParams& slider) const {
  int kMidX = rect.x() + rect.width() / 2;
  int kMidY = rect.y() + rect.height() / 2;

  SkPaint paint;
  paint.setColor(kSliderTrackBackgroundColor);

  SkRect skrect;
  if (slider.vertical) {
    skrect.set(std::max(rect.x(), kMidX - 2),
               rect.y(),
               std::min(rect.right(), kMidX + 2),
               rect.bottom());
  } else {
    skrect.set(rect.x(),
               std::max(rect.y(), kMidY - 2),
               rect.right(),
               std::min(rect.bottom(), kMidY + 2));
  }
  canvas->drawRect(skrect, paint);
}

void NativeThemeAndroid::PaintSliderThumb(
    SkCanvas* canvas,
    State state,
    const gfx::Rect& rect,
    const SliderExtraParams& slider) const {
  bool hovered = (state == kHovered) || slider.in_drag;
  int kMidX = rect.x() + rect.width() / 2;
  int kMidY = rect.y() + rect.height() / 2;

  SkPaint paint;
  paint.setColor(hovered ? SK_ColorWHITE : kSliderThumbLightGrey);

  SkIRect skrect;
  if (slider.vertical)
    skrect.set(rect.x(), rect.y(), kMidX + 1, rect.bottom());
  else
    skrect.set(rect.x(), rect.y(), rect.right(), kMidY + 1);

  canvas->drawIRect(skrect, paint);

  paint.setColor(hovered ? kSliderThumbLightGrey : kSliderThumbDarkGrey);

  if (slider.vertical)
    skrect.set(kMidX + 1, rect.y(), rect.right(), rect.bottom());
  else
    skrect.set(rect.x(), kMidY + 1, rect.right(), rect.bottom());

  canvas->drawIRect(skrect, paint);

  paint.setColor(kSliderThumbBorderDarkGrey);
  DrawBox(canvas, rect, paint);

  if (rect.height() > 10 && rect.width() > 10) {
    DrawHorizLine(canvas, kMidX - 2, kMidX + 2, kMidY, paint);
    DrawHorizLine(canvas, kMidX - 2, kMidX + 2, kMidY - 3, paint);
    DrawHorizLine(canvas, kMidX - 2, kMidX + 2, kMidY + 3, paint);
  }
}

void NativeThemeAndroid::PaintInnerSpinButton(
    SkCanvas* canvas,
    State state,
    const gfx::Rect& rect,
    const InnerSpinButtonExtraParams& spin_button) const {
  if (spin_button.read_only)
    state = kDisabled;

  State north_state = state;
  State south_state = state;
  if (spin_button.spin_up)
    south_state = south_state != kDisabled ? kNormal : kDisabled;
  else
    north_state = north_state != kDisabled ? kNormal : kDisabled;

  gfx::Rect half = rect;
  half.set_height(rect.height() / 2);
  PaintArrowButton(canvas, half, kScrollbarUpArrow, north_state);

  half.set_y(rect.y() + rect.height() / 2);
  PaintArrowButton(canvas, half, kScrollbarDownArrow, south_state);
}

void NativeThemeAndroid::PaintProgressBar(
    SkCanvas* canvas,
    State state,
    const gfx::Rect& rect,
    const ProgressBarExtraParams& progress_bar) const {
  ResourceBundle& rb = ResourceBundle::GetSharedInstance();
  gfx::ImageSkia* bar_image = rb.GetImageSkiaNamed(IDR_PROGRESS_BAR);
  gfx::ImageSkia* left_border_image = rb.GetImageSkiaNamed(
      IDR_PROGRESS_BORDER_LEFT);
  gfx::ImageSkia* right_border_image = rb.GetImageSkiaNamed(
      IDR_PROGRESS_BORDER_RIGHT);

  float tile_scale = static_cast<float>(rect.height()) /
      bar_image->height();

  int new_tile_width = static_cast<int>(bar_image->width() * tile_scale);
  float tile_scale_x = static_cast<float>(new_tile_width) /
      bar_image->width();

  DrawTiledImage(canvas, *bar_image, 0, 0, tile_scale_x, tile_scale,
      rect.x(), rect.y(), rect.width(), rect.height());

  if (progress_bar.value_rect_width) {
    gfx::ImageSkia* value_image = rb.GetImageSkiaNamed(IDR_PROGRESS_VALUE);

    new_tile_width = static_cast<int>(value_image->width() * tile_scale);
    tile_scale_x = static_cast<float>(new_tile_width) /
        value_image->width();

    DrawTiledImage(canvas, *value_image, 0, 0, tile_scale_x, tile_scale,
        progress_bar.value_rect_x,
        progress_bar.value_rect_y,
        progress_bar.value_rect_width,
        progress_bar.value_rect_height);
  }

  int dest_left_border_width = static_cast<int>(left_border_image->width() *
      tile_scale);
  DrawImageInt(canvas, *left_border_image, 0, 0, left_border_image->width(),
      left_border_image->height(), rect.x(), rect.y(), dest_left_border_width,
      rect.height());

  int dest_right_border_width = static_cast<int>(right_border_image->width() *
      tile_scale);
  int dest_x = rect.right() - dest_right_border_width;
  DrawImageInt(canvas, *right_border_image, 0, 0, right_border_image->width(),
      right_border_image->height(), dest_x, rect.y(), dest_right_border_width,
      rect.height());
}

bool NativeThemeAndroid::IntersectsClipRectInt(SkCanvas* canvas,
                                               int x,
                                               int y,
                                               int w,
                                               int h) const {
  SkRect clip;
  return canvas->getClipBounds(&clip) &&
      clip.intersect(SkIntToScalar(x), SkIntToScalar(y), SkIntToScalar(x + w),
                     SkIntToScalar(y + h));
}

void NativeThemeAndroid::DrawImageInt(SkCanvas* sk_canvas,
                                       const gfx::ImageSkia& image,
                                       int src_x,
                                       int src_y,
                                       int src_w,
                                       int src_h,
                                       int dest_x,
                                       int dest_y,
                                       int dest_w,
                                       int dest_h) const {
  // TODO(pkotwicz): Do something better and don't infer device
  // scale factor from canvas scale.
  SkMatrix m = sk_canvas->getTotalMatrix();
  ui::ScaleFactor device_scale_factor = ui::GetScaleFactorFromScale(
      SkScalarAbs(m.getScaleX()));
  scoped_ptr<gfx::Canvas> canvas(gfx::Canvas::CreateCanvasWithoutScaling(
      sk_canvas, device_scale_factor));
  canvas->DrawImageInt(image, src_x, src_y, src_w, src_h,
      dest_x, dest_y, dest_w, dest_h, true);
}

void NativeThemeAndroid::DrawTiledImage(SkCanvas* sk_canvas,
                                        const gfx::ImageSkia& image,
                                        int src_x,
                                        int src_y,
                                        float tile_scale_x,
                                        float tile_scale_y,
                                        int dest_x,
                                        int dest_y,
                                        int w,
                                        int h) const {
  // TODO(pkotwicz): Do something better and don't infer device
  // scale factor from canvas scale.
  SkMatrix m = sk_canvas->getTotalMatrix();
  ui::ScaleFactor device_scale_factor = ui::GetScaleFactorFromScale(
      SkScalarAbs(m.getScaleX()));
  scoped_ptr<gfx::Canvas> canvas(gfx::Canvas::CreateCanvasWithoutScaling(
      sk_canvas, device_scale_factor));
  canvas->TileImageInt(image, src_x, src_y, tile_scale_x,
      tile_scale_y, dest_x, dest_y, w, h);
}

SkColor NativeThemeAndroid::SaturateAndBrighten(
    SkScalar* hsv,
    SkScalar saturate_amount,
    SkScalar brighten_amount) const {
  SkScalar color[3];
  color[0] = hsv[0];
  color[1] = Clamp(hsv[1] + saturate_amount, 0.0, 1.0);
  color[2] = Clamp(hsv[2] + brighten_amount, 0.0, 1.0);
  return SkHSVToColor(color);
}

SkScalar NativeThemeAndroid::Clamp(SkScalar value,
                                   SkScalar min,
                                   SkScalar max) const {
  return std::min(std::max(value, min), max);
}

void NativeThemeAndroid::DrawVertLine(SkCanvas* canvas,
                                      int x,
                                      int y1,
                                      int y2,
                                      const SkPaint& paint) const {
  SkIRect skrect;
  skrect.set(x, y1, x + 1, y2 + 1);
  canvas->drawIRect(skrect, paint);
}

void NativeThemeAndroid::DrawHorizLine(SkCanvas* canvas,
                                       int x1,
                                       int x2,
                                       int y,
                                       const SkPaint& paint) const {
  SkIRect skrect;
  skrect.set(x1, y, x2 + 1, y + 1);
  canvas->drawIRect(skrect, paint);
}

void NativeThemeAndroid::DrawBox(SkCanvas* canvas,
                                 const gfx::Rect& rect,
                                 const SkPaint& paint) const {
  int right = rect.x() + rect.width() - 1;
  int bottom = rect.y() + rect.height() - 1;
  DrawHorizLine(canvas, rect.x(), right, rect.y(), paint);
  DrawVertLine(canvas, right, rect.y(), bottom, paint);
  DrawHorizLine(canvas, rect.x(), right, bottom, paint);
  DrawVertLine(canvas, rect.x(), rect.y(), bottom, paint);
}

SkColor NativeThemeAndroid::OutlineColor(SkScalar* hsv1, SkScalar* hsv2) const {
  SkScalar min_diff = Clamp((hsv1[1] + hsv2[1]) * 1.2, 0.28, 0.5);
  SkScalar diff = Clamp(fabs(hsv1[2] - hsv2[2]) / 2, min_diff, 0.5);

  if (hsv1[2] + hsv2[2] > 1.0)
    diff = -diff;

  return SaturateAndBrighten(hsv2, -0.2, diff);
}

}  // namespace ui