// Copyright 2016 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_GTK_NATIVE_THEME_GTK_H_
#define UI_GTK_NATIVE_THEME_GTK_H_

#include "base/callback_list.h"
#include "base/macros.h"
#include "base/no_destructor.h"
#include "third_party/abseil-cpp/absl/types/optional.h"
#include "ui/base/glib/glib_signal.h"
#include "ui/base/glib/scoped_gobject.h"
#include "ui/native_theme/native_theme_base.h"

typedef struct _GtkCssProvider GtkCssProvider;
typedef struct _GtkParamSpec GtkParamSpec;
typedef struct _GtkSettings GtkSettings;

namespace gtk {

using ScopedCssProvider = ScopedGObject<GtkCssProvider>;

// A version of NativeTheme that uses GTK-rendered widgets.
class NativeThemeGtk : public ui::NativeThemeBase {
 public:
  static NativeThemeGtk* instance();

  // ui::NativeThemeBase:
  void PaintArrowButton(cc::PaintCanvas* canvas,
                        const gfx::Rect& rect,
                        Part direction,
                        State state,
                        ColorScheme color_scheme,
                        const ScrollbarArrowExtraParams& arrow) const override;
  void PaintScrollbarTrack(cc::PaintCanvas* canvas,
                           Part part,
                           State state,
                           const ScrollbarTrackExtraParams& extra_params,
                           const gfx::Rect& rect,
                           ColorScheme color_scheme) const override;
  void PaintScrollbarThumb(cc::PaintCanvas* canvas,
                           Part part,
                           State state,
                           const gfx::Rect& rect,
                           NativeTheme::ScrollbarOverlayColorTheme theme,
                           ColorScheme color_scheme) const override;
  void PaintScrollbarCorner(cc::PaintCanvas* canvas,
                            State state,
                            const gfx::Rect& rect,
                            ColorScheme color_scheme) const override;
  void PaintMenuPopupBackground(
      cc::PaintCanvas* canvas,
      const gfx::Size& size,
      const MenuBackgroundExtraParams& menu_background,
      ColorScheme color_scheme) const override;
  void PaintMenuSeparator(cc::PaintCanvas* canvas,
                          State state,
                          const gfx::Rect& rect,
                          const MenuSeparatorExtraParams& menu_separator,
                          ColorScheme color_scheme) const override;
  void PaintMenuItemBackground(cc::PaintCanvas* canvas,
                               State state,
                               const gfx::Rect& rect,
                               const MenuItemExtraParams& menu_item,
                               ColorScheme color_scheme) const override;
  void PaintFrameTopArea(cc::PaintCanvas* canvas,
                         State state,
                         const gfx::Rect& rect,
                         const FrameTopAreaExtraParams& frame_top_area,
                         ColorScheme color_scheme) const override;
  void NotifyOnNativeThemeUpdated() override;

  void OnThemeChanged(GtkSettings* settings, GtkParamSpec* param);

 protected:
  // ui::NativeThemeBase:
  bool AllowColorPipelineRedirection(ColorScheme color_scheme) const override;
  SkColor GetSystemColorDeprecated(ColorId color_id,
                                   ColorScheme color_scheme,
                                   bool apply_processing) const override;

 private:
  friend class base::NoDestructor<NativeThemeGtk>;

  NativeThemeGtk();
  ~NativeThemeGtk() override;

  void SetThemeCssOverride(ScopedCssProvider provider);

  mutable absl::optional<SkColor> color_cache_[kColorId_NumColors];

  ScopedCssProvider theme_css_override_;

  DISALLOW_COPY_AND_ASSIGN(NativeThemeGtk);
};

}  // namespace gtk

#endif  // UI_GTK_NATIVE_THEME_GTK_H_