/*************************************************************************

 * Copyright (C) 2014 by Hugo Pereira Da Costa <hugo.pereira@free.fr>    *

 * Copyright (C) 2014-2018 Martin Bříza <m@rtinbriza.cz>                 *

 * Copyright (C) 2019 Jan Grulich <jgrulich@redhat.com>                  *

 *                                                                       *

 * This program is free software; you can redistribute it and/or modify  *

 * it under the terms of the GNU General Public License as published by  *

 * the Free Software Foundation; either version 2 of the License, or     *

 * (at your option) any later version.                                   *

 *                                                                       *

 * This program is distributed in the hope that it will be useful,       *

 * but WITHOUT ANY WARRANTY; without even the implied warranty of        *

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *

 * GNU General Public License for more details.                          *

 *                                                                       *

 * You should have received a copy of the GNU General Public License     *

 * along with this program; if not, write to the                         *

 * Free Software Foundation, Inc.,                                       *

 * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA .        *

 *************************************************************************/

#ifndef ADWAITA_STYLE_H

#define ADWAITA_STYLE_H

#include "adwaita.h"

#include "config-adwaita.h"

#include <QAbstractItemView>

#include <QAbstractScrollArea>

#include <QCommonStyle>

#include <QDockWidget>

#include <QHash>

#include <QIcon>

#include <QMdiSubWindow>

#include <QStyleOption>

#include <QWidget>

#include <QCommandLinkButton>

namespace AdwaitaPrivate

{

class TabBarData;

}

namespace Adwaita

{

class Animations;

class Helper;

class Mnemonics;

class SplitterFactory;

class WidgetExplorer;

class WindowManager;

//* convenience typedef for base class

using ParentStyleClass = QCommonStyle;

//* base class for adwaita style

/** it is responsible to draw all the primitives to be displayed on screen, on request from Qt paint engine */

class Style : public ParentStyleClass

{

    Q_OBJECT

    /* this tells kde applications that custom style elements are supported, using the kstyle mechanism */

    Q_CLASSINFO("X-KDE-CustomElements", "true")

public:

    //* constructor

    explicit Style(bool dark);

    //* destructor

    virtual ~Style(void);

    //* needed to avoid warnings at compilation time

    using ParentStyleClass::polish;

    using ParentStyleClass::unpolish;

    //* widget polishing

    virtual void polish(QWidget *widget);

    //* widget unpolishing

    virtual void unpolish(QWidget *widget);

    //* palette polishing

    virtual void polish(QPalette &palette);

    virtual QPalette standardPalette() const;

    //* polish scrollarea

    void polishScrollArea(QAbstractScrollArea *scrollArea);

    //* pixel metrics

    virtual int pixelMetric(PixelMetric metric, const QStyleOption *option = nullptr, const QWidget *widget = nullptr) const;

    //* style hints

    virtual int styleHint(StyleHint hint, const QStyleOption *option = nullptr, const QWidget *widget = nullptr, QStyleHintReturn *returnData = nullptr) const;

    //* returns rect corresponding to one widget's subelement

    virtual QRect subElementRect(SubElement element, const QStyleOption *option, const QWidget *widget) const;

    //* returns rect corresponding to one widget's subcontrol

    virtual QRect subControlRect(ComplexControl element, const QStyleOptionComplex *option, SubControl subControl, const QWidget *widget) const;

    //* returns size matching contents

    QSize sizeFromContents(ContentsType element, const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    //* returns which subcontrol given QPoint corresponds to

    SubControl hitTestComplexControl(ComplexControl control, const QStyleOptionComplex *option , const QPoint &point, const QWidget *widget) const;

    //* primitives

    void drawPrimitive(PrimitiveElement element, const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    //* controls

    void drawControl(ControlElement element, const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    //* complex controls

    void drawComplexControl(ComplexControl element, const QStyleOptionComplex *option, QPainter *painter, const QWidget *widget) const;

    //* generic text rendering

    virtual void drawItemText(QPainter *painter, const QRect &rect, int alignment, const QPalette &palette, bool enabled,

                              const QString &text, QPalette::ColorRole textRole = QPalette::NoRole) const;

    //*@name event filters

    //@{

    virtual bool eventFilter(QObject *object, QEvent *event);

    bool eventFilterScrollArea(QWidget *widget, QEvent *event);

    bool eventFilterComboBoxContainer(QWidget *widget, QEvent *event);

    bool eventFilterDockWidget(QDockWidget *dockWidget, QEvent *event);

    bool eventFilterMdiSubWindow(QMdiSubWindow *subWindow, QEvent *event);

    bool eventFilterCommandLinkButton(QCommandLinkButton *button, QEvent *event);

    //* install event filter to object, in a unique way

    void addEventFilter(QObject *object)

    {

        object->removeEventFilter(this);

        object->installEventFilter(this);

    }

    //@}

protected Q_SLOTS:

    //* update configuration

    void configurationChanged(void);

    //* standard icons

    virtual QIcon standardIconImplementation(StandardPixmap standardPixmap, const QStyleOption *option, const QWidget *widget) const;

protected:

    //* standard icons

    virtual QIcon standardIcon(StandardPixmap pixmap, const QStyleOption *option = nullptr, const QWidget *widget = nullptr) const

    {

        return standardIconImplementation(pixmap, option, widget);

    }

    //* load configuration

    void loadConfiguration();

    //*@name subelementRect specialized functions

    //@{

    //* default implementation. Does not change anything

    QRect defaultSubElementRect(const QStyleOption *option, const QWidget *widget) const

    {

        return option->rect;

    }

    QRect pushButtonContentsRect(const QStyleOption *option, const QWidget *widget) const;

    QRect pushButtonFocusRect(const QStyleOption *option, const QWidget *widget) const;

    QRect checkBoxContentsRect(const QStyleOption *option, const QWidget *widget) const;

    QRect checkBoxIndicatorRect(const QStyleOption *option, const QWidget *widget) const;

    QRect checkBoxFocusRect(const QStyleOption *option, const QWidget *widget) const;

    QRect lineEditContentsRect(const QStyleOption *option, const QWidget *widget) const;

    QRect progressBarGrooveRect(const QStyleOption *option, const QWidget *widget) const;

    QRect progressBarContentsRect(const QStyleOption *option, const QWidget *widget) const;

    QRect progressBarLabelRect(const QStyleOption *option, const QWidget *widget) const;

    QRect headerArrowRect(const QStyleOption *option, const QWidget *widget) const;

    QRect headerLabelRect(const QStyleOption *option, const QWidget *widget) const;

    QRect sliderFocusRect(const QStyleOption *option, const QWidget *widget) const;

    QRect tabBarTabLeftButtonRect(const QStyleOption *option, const QWidget *widget) const;

    QRect tabBarTabRightButtonRect(const QStyleOption *option, const QWidget *widget) const;

    QRect tabWidgetTabBarRect(const QStyleOption *option, const QWidget *widget) const;

    QRect tabWidgetTabContentsRect(const QStyleOption *option, const QWidget *widget) const;

    QRect tabWidgetTabPaneRect(const QStyleOption *option, const QWidget *widget) const;

    QRect tabWidgetCornerRect(SubElement element, const QStyleOption *option, const QWidget *widget) const;

    QRect toolBoxTabContentsRect(const QStyleOption *option, const QWidget *widget) const;

    QRect genericLayoutItemRect(const QStyleOption *option, const QWidget *widget) const;

    //@}option

    //*@name subcontrol Rect specialized functions

    //@{

    QRect groupBoxSubControlRect(const QStyleOptionComplex *option, SubControl subControl, const QWidget *widget) const;

    QRect toolButtonSubControlRect(const QStyleOptionComplex *option, SubControl subControl, const QWidget *widget) const;

    QRect comboBoxSubControlRect(const QStyleOptionComplex *option, SubControl subControl, const QWidget *widget) const;

    QRect spinBoxSubControlRect(const QStyleOptionComplex *option, SubControl subControl, const QWidget *widget) const;

    QRect scrollBarInternalSubControlRect(const QStyleOptionComplex *option, SubControl subControl) const;

    QRect scrollBarSubControlRect(const QStyleOptionComplex *option, SubControl subControl, const QWidget *widget) const;

    QRect dialSubControlRect(const QStyleOptionComplex *option, SubControl subControl, const QWidget *widget) const;

    QRect sliderSubControlRect(const QStyleOptionComplex *option, SubControl subControl, const QWidget *widget) const;

    //@}

    //*@name sizeFromContents

    //@{

    QSize defaultSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const

    {

        return size;

    }

    QSize checkBoxSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize lineEditSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize comboBoxSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize spinBoxSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize sliderSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize pushButtonSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize toolButtonSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize menuBarItemSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize menuItemSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize progressBarSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize tabWidgetSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize tabBarTabSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize headerSectionSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    QSize itemViewItemSizeFromContents(const QStyleOption *option, const QSize &size, const QWidget *widget) const;

    //@}

    //*@name primitives specialized functions

    //@{

    bool emptyPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const

    {

        return true;

    }

    bool drawFramePrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawFrameLineEditPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawFrameFocusRectPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawFrameMenuPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawFrameGroupBoxPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawFrameTabWidgetPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawFrameTabBarBasePrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawFrameWindowPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawIndicatorArrowUpPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const

    {

        return drawIndicatorArrowPrimitive(ArrowUp, option, painter, widget);

    }

    bool drawIndicatorArrowDownPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const

    {

        return drawIndicatorArrowPrimitive(ArrowDown, option, painter, widget);

    }

    bool drawIndicatorArrowLeftPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const

    {

        return drawIndicatorArrowPrimitive(ArrowLeft, option, painter, widget);

    }

    bool drawIndicatorArrowRightPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const

    {

        return drawIndicatorArrowPrimitive(ArrowRight, option, painter, widget);

    }

    bool drawIndicatorArrowPrimitive(ArrowOrientation orientation, const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawIndicatorHeaderArrowPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawPanelButtonCommandPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawPanelButtonToolPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawTabBarPanelButtonToolPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawPanelScrollAreaCornerPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawPanelMenuPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawPanelTipLabelPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawPanelItemViewRowPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawPanelItemViewItemPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawIndicatorCheckBoxPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawIndicatorRadioButtonPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawIndicatorButtonDropDownPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawIndicatorTabClosePrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawIndicatorTabTearPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawIndicatorToolBarHandlePrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawIndicatorToolBarSeparatorPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    bool drawIndicatorBranchPrimitive(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    //@}

    //*@name controls specialized functions

    //@{

    bool emptyControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const

    {

        return true;

    }

    virtual bool drawPushButtonLabelControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawToolButtonLabelControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawCheckBoxLabelControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawComboBoxLabelControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawItemViewItemControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawMenuBarEmptyArea(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawMenuBarItemControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawMenuItemControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawProgressBarControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawProgressBarContentsControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawProgressBarGrooveControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawProgressBarLabelControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawScrollBarSliderControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawScrollBarAddLineControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawScrollBarSubLineControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawShapedFrameControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawRubberBandControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawHeaderSectionControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawHeaderLabelControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawHeaderEmptyAreaControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawTabBarTabLabelControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawTabBarTabShapeControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawToolBoxTabLabelControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawToolBoxTabShapeControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    virtual bool drawDockWidgetTitleControl(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    //*@}

    //*@name complex ontrols specialized functions

    //@{

    bool drawGroupBoxComplexControl(const QStyleOptionComplex *option, QPainter *painter, const QWidget *widget) const;

    bool drawToolButtonComplexControl(const QStyleOptionComplex *option, QPainter *painter, const QWidget *widget) const;

    bool drawComboBoxComplexControl(const QStyleOptionComplex *option, QPainter *painter, const QWidget *widget) const;

    bool drawSpinBoxComplexControl(const QStyleOptionComplex *option, QPainter *painter, const QWidget *widget) const;

    bool drawSliderComplexControl(const QStyleOptionComplex *option, QPainter *painter, const QWidget *widget) const;

    bool drawDialComplexControl(const QStyleOptionComplex *option, QPainter *painter, const QWidget *widget) const;

    bool drawScrollBarComplexControl(const QStyleOptionComplex *option, QPainter *painter, const QWidget *widget) const;

    bool drawTitleBarComplexControl(const QStyleOptionComplex *option, QPainter *painter, const QWidget *widget) const;

    //@}

    //!*@name various utilty functions

    //@{

    //* spinbox arrows

    void renderSpinBoxArrow(const SubControl &subControl, const QStyleOptionSpinBox *option, QPainter *painter, const QWidget *widget) const;

    //* menu title

    void renderMenuTitle(const QStyleOptionToolButton *option, QPainter *painter, const QWidget *widget) const;

    //* return dial angle based on option and value

    qreal dialAngle(const QStyleOptionSlider *sliderOption, int value) const;

    //* returns relevant scrollbar parent

    /** needed to detect parent focus */

    const QWidget *scrollBarParent(const QWidget *widget) const;

    //* returns true if given scrollbar arrow is animated

    QColor scrollBarArrowColor(const QStyleOptionSlider *option, const SubControl &control, const QWidget *widget) const;

    //* scrollbar buttons

    enum ScrollBarButtonType {

        NoButton,

        SingleButton,

        DoubleButton

    };

    //* returns height for scrollbar buttons depending of button types

    int scrollBarButtonHeight(const ScrollBarButtonType &type) const

    {

        switch (type) {

        case NoButton:

            return Metrics::ScrollBar_NoButtonHeight;

        case SingleButton:

            return Metrics::ScrollBar_SingleButtonHeight;

        case DoubleButton:

            return Metrics::ScrollBar_DoubleButtonHeight;

        default:

            return 0;

        }

    }

    //@}

    //* translucent background

    void setTranslucentBackground(QWidget *widget) const;

    /**

    separator can have a title and an icon

    in that case they are rendered as sunken flat toolbuttons

    return toolbutton option that matches named separator menu items

    */

    QStyleOptionToolButton separatorMenuItemOption(const QStyleOptionMenuItem *menuItemOption, const QWidget *widget) const;

    //* create toolbar extension icon

    QIcon toolBarExtensionIcon(StandardPixmap, const QStyleOption *option, const QWidget *widget) const;

    //* create title bar button icon

    QIcon titleBarButtonIcon(StandardPixmap, const QStyleOption *option, const QWidget *widget) const;

    //* returns item view parent if any

    /** needed to have correct color on focused checkboxes and radiobuttons */

    const QAbstractItemView *itemViewParent(const QWidget *widget) const;

    //* returns true if a given widget is a selected item in a focused list

    /**

    This is necessary to have the correct colors used for e.g. checkboxes and radiobuttons in lists

    @param widget The widget to be checked

    @param position Used to find the relevant QModelIndex

    */

    bool isSelectedItem(const QWidget *widget, const QPoint &localPosition) const;

    //* return true if option corresponds to QtQuick control

    bool isQtQuickControl(const QStyleOption *option, const QWidget *widget) const;

    //@}

    //* adjust rect based on provided margins

    QRect insideMargin(const QRect &r, int margin) const

    {

        return insideMargin(r, margin, margin);

    }

    //* adjust rect based on provided margins

    QRect insideMargin(const QRect &r, int marginWidth, int marginHeight) const

    {

        return r.adjusted(marginWidth, marginHeight, -marginWidth, -marginHeight);

    }

    //* expand size based on margins

    QSize expandSize(const QSize &size, int margin) const

    {

        return expandSize(size, margin, margin);

    }

    //* expand size based on margins

    QSize expandSize(const QSize &size, int marginWidth, int marginHeight) const

    {

        return size + 2 * QSize(marginWidth, marginHeight);

    }

    //* returns true for vertical tabs

    bool isVerticalTab(const QStyleOptionTab *option) const

    {

        return isVerticalTab(option->shape);

    }

    bool isVerticalTab(const QTabBar::Shape &shape) const

    {

        return shape == QTabBar::RoundedEast

               || shape == QTabBar::RoundedWest

               || shape == QTabBar::TriangularEast

               || shape == QTabBar::TriangularWest;

    }

    //* right to left alignment handling

    using ParentStyleClass::visualRect;

    QRect visualRect(const QStyleOption *opt, const QRect &subRect) const

    {

        return ParentStyleClass::visualRect(opt->direction, opt->rect, subRect);

    }

    //* centering

    QRect centerRect(const QRect &rect, const QSize &size) const

    {

        return centerRect(rect, size.width(), size.height());

    }

    QRect centerRect(const QRect &rect, int width, int height) const

    {

        return QRect(rect.left() + (rect.width() - width) / 2, rect.top() + (rect.height() - height) / 2, width, height);

    }

    /*

    Checks whether the point is before the bound rect for bound of given orientation.

    This is needed to implement custom number of buttons in scrollbars,

    as well as proper mouse-hover

    */

    inline bool preceeds(const QPoint &point, const QRect &bound, const QStyleOption *option) const;

    //* return which arrow button is hit by point for scrollbar double buttons

    inline QStyle::SubControl scrollBarHitTest(const QRect &rect, const QPoint &point, const QStyleOption *option) const;

    //! return true if one of the widget's parent inherits requested type

    inline bool hasParent(const QWidget *widget, const char *className) const;

    //* return true if one of the widget's parent inherits requested type

    template<typename T> bool hasParent(const QWidget *widget) const;

    //* return true if icons should be shown in menus

    bool showIconsInMenuItems(void) const;

    //* return true if icons should be shown on buttons

    bool showIconsOnPushButtons(void) const;

    //* return true if passed widget is a menu title (KMenu::addTitle)

    bool isMenuTitle(const QWidget *widget) const;

    //* return true if passed widget is a menu title (KMenu::addTitle)

    bool hasAlteredBackground(const QWidget *widget) const;

private:

    //*@name scrollbar button types (for addLine and subLine )

    //@{

    ScrollBarButtonType _addLineButtons;

    ScrollBarButtonType _subLineButtons;

    //@}

    //* helper

    Helper *_helper;

    //* animations

    Animations *_animations;

    //* keyboard accelerators

    Mnemonics *_mnemonics;

    //* window manager

    WindowManager *_windowManager;

    //* splitter Factory, to extend splitters hit area

    SplitterFactory *_splitterFactory;

    //* widget explorer

    WidgetExplorer *_widgetExplorer;

    //* tabbar data

    AdwaitaPrivate::TabBarData *_tabBarData;

    //* icon hash

    using IconCache = QHash<StandardPixmap, QIcon>;

    IconCache _iconCache;

    //* pointer to primitive specialized function

    using StylePrimitive = bool(Style::*)(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    StylePrimitive _frameFocusPrimitive = nullptr;

    //* pointer to control specialized function

    using StyleControl = bool (Style::*)(const QStyleOption *option, QPainter *painter, const QWidget *widget) const;

    //* pointer to control specialized function

    using StyleComplexControl = bool (Style::*)(const QStyleOptionComplex *option, QPainter *painter, const QWidget *widget) const;

    //*@name custom elements

    //@{

    //* use Argb Drag and Drop Window

    QStyle::StyleHint SH_ArgbDndWindow;

    //! styled painting for KCapacityBar

    QStyle::ControlElement CE_CapacityBar;

    bool _dark { false };

    bool _isGNOME { false };

    bool _isKDE { false };

    //@}

};

//_________________________________________________________________________

bool Style::preceeds(const QPoint &point, const QRect &bound, const QStyleOption *option) const

{

    if (option->state & QStyle::State_Horizontal) {

        if (option->direction == Qt::LeftToRight)

            return point.x() < bound.right();

        else

            return point.x() > bound.x();

    } else

        return point.y() < bound.y();

}

//_________________________________________________________________________

QStyle::SubControl Style::scrollBarHitTest(const QRect &rect, const QPoint &point, const QStyleOption *option) const

{

    if (option->state & QStyle::State_Horizontal) {

        if (option->direction == Qt::LeftToRight)

            return point.x() < rect.center().x() ? QStyle::SC_ScrollBarSubLine : QStyle::SC_ScrollBarAddLine;

        else

            return point.x() > rect.center().x() ? QStyle::SC_ScrollBarSubLine : QStyle::SC_ScrollBarAddLine;

    } else

        return point.y() < rect.center().y() ? QStyle::SC_ScrollBarSubLine : QStyle::SC_ScrollBarAddLine;

}

//_________________________________________________________________________

bool Style::hasParent(const QWidget *widget, const char *className) const

{

    if (!widget)

        return false;

    while ((widget = widget->parentWidget())) {

        if (widget->inherits(className))

            return true;

    }

    return false;

}

//_________________________________________________________________________

template< typename T > bool Style::hasParent(const QWidget *widget) const

{

    if (!widget)

        return false;

    while ((widget = widget->parentWidget())) {

        if (qobject_cast<const T *>(widget))

            return true;

    }

    return false;

}

} // namespace Adwaita

#endif // ADWAITA_STYLE_H