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** This file is part of the Qt Quick Controls 2 module of the Qt Toolkit.
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#include "qquickstyleitemscrollbar.h"

QFont QQuickStyleItemScrollBar::styleFont(QQuickItem *control) const
{
    return style()->font(QStyle::CE_ProgressBarLabel, controlSize(control));
}

void QQuickStyleItemScrollBar::connectToControl() const
{
    QQuickStyleItem::connectToControl();
    auto scrollBar = control<QQuickScrollBar>();
    connect(scrollBar, &QQuickScrollBar::orientationChanged, this, &QQuickStyleItem::markImageDirty);
    connect(scrollBar, &QQuickScrollBar::pressedChanged, this, &QQuickStyleItem::markImageDirty);
}

StyleItemGeometry QQuickStyleItemScrollBar::calculateGeometry()
{
    QStyleOptionSlider styleOption;
    initStyleOption(styleOption);

    StyleItemGeometry geometry;
    geometry.minimumSize = style()->sizeFromContents(QStyle::CT_ScrollBar, &styleOption, QSize(0, 0));
    geometry.implicitSize = geometry.minimumSize;
    styleOption.rect = QRect(QPoint(0, 0), geometry.implicitSize);
    geometry.layoutRect = style()->subElementRect(QStyle::SE_ScrollBarLayoutItem, &styleOption);
    geometry.ninePatchMargins = style()->ninePatchMargins(QStyle::CC_ScrollBar, &styleOption, geometry.minimumSize);

    return geometry;
}

void QQuickStyleItemScrollBar::paintEvent(QPainter *painter) const
{
    QStyleOptionSlider styleOption;
    initStyleOption(styleOption);
    style()->drawComplexControl(QStyle::CC_ScrollBar, &styleOption, painter);
}

void QQuickStyleItemScrollBar::initStyleOption(QStyleOptionSlider &styleOption) const
{
    initStyleOptionBase(styleOption);
    auto scrollBar = control<QQuickScrollBar>();

    styleOption.subControls = m_subControl == Groove
                            ? QStyle::SC_ScrollBarGroove | QStyle::SC_ScrollBarAddLine | QStyle::SC_ScrollBarSubLine
                            : QStyle::SC_ScrollBarSlider;
    styleOption.activeSubControls = QStyle::SC_None;
    styleOption.orientation = scrollBar->orientation();
    if (styleOption.orientation == Qt::Horizontal)
        styleOption.state |= QStyle::State_Horizontal;

    if (scrollBar->isPressed())
        styleOption.state |= QStyle::State_Sunken;

    if (m_overrideState != None) {
        // In ScrollBar.qml we fade between two versions of
        // the handle, depending on if it's hovered or not
        if (m_overrideState & AlwaysHovered) {
            styleOption.state |= QStyle::State_Sunken;
            styleOption.activeSubControls = (styleOption.subControls & (QStyle::SC_ScrollBarSlider | QStyle::SC_ScrollBarGroove));
        } else if (m_overrideState & NeverHovered) {
            styleOption.state &= ~QStyle::State_Sunken;
            styleOption.activeSubControls &= ~(styleOption.subControls & (QStyle::SC_ScrollBarSlider | QStyle::SC_ScrollBarGroove));
        }
    }

    // The following values will let the handle fill 100% of the
    // groove / imageSize. But when the handle is resized by
    // QQuickScrollBar, it will end up with the correct size visually.
    styleOption.pageStep = 1000;
    styleOption.minimum = 0;
    styleOption.maximum = 1;
    styleOption.sliderValue = 0;
}
