// A proxy style with debugging output wrapped around the base style
// for debugging metrics,etc.
// 1.0, 6.8.2014

#include <QApplication>
#include <QDesktopWidget>
#include <QSpinBox>
#include <QDebug>
#include <QStyle>
#include <QStyleOption>
#include <QProxyStyle>
#include <QFontMetrics>
#include <QVariant>

class DebugStyle : public QProxyStyle {
public:
    static QString debugWidget(const QWidget *widget = 0)
    {
        if (!widget)
            return QStringLiteral("widget=NULL");
        const QString on = widget->objectName();
        if (!on.isEmpty())
            return on;
        return widget->metaObject()->className();
    }
    static QString debugQStyleOption(const QStyleOption *option)
    {
        QString result;
        if (option)
            QDebug(&result) << "optRec=" << option->rect;
        else
            result = QStringLiteral("option=NULL");
        return result;
    }

    DebugStyle(QStyle *style) : QProxyStyle(style)
    {
          qDebug() << __FUNCTION__ << style->objectName() << "devicePixelRatio=" << qApp->devicePixelRatio();
    }

    void drawPrimitive(PrimitiveElement element, const QStyleOption *option, QPainter *painter, const QWidget *widget = 0) const
    {
        qDebug() << __FUNCTION__ << "element="<< element
                 << DebugStyle::debugQStyleOption(option) << DebugStyle::debugWidget(widget);
        QProxyStyle::drawPrimitive( element, option, painter, widget);
    }

    void drawControl(ControlElement element, const QStyleOption *option, QPainter *painter, const QWidget *widget = 0) const
    {
        qDebug() << __FUNCTION__ << "element="<< element
                 << DebugStyle::debugQStyleOption(option) << DebugStyle::debugWidget(widget);
        QProxyStyle::drawControl(element, option, painter, widget);
    }
    void drawComplexControl(ComplexControl control, const QStyleOptionComplex *option, QPainter *painter, const QWidget *widget = 0) const
    {
        qDebug() << __FUNCTION__ << "control="<< control
                 << DebugStyle::debugQStyleOption(option) << DebugStyle::debugWidget(widget);
        QProxyStyle::drawComplexControl(control, option, painter, widget);
    }
    void drawItemPixmap(QPainter *painter, const QRect &rect, int alignment, const QPixmap &pixmap) const
    {
        qDebug() << __FUNCTION__ << rect << "alignment=" << alignment << pixmap;
        QProxyStyle::drawItemPixmap(painter, rect, alignment, pixmap);
    }

    QSize sizeFromContents(ContentsType type, const QStyleOption *option, const QSize &size, const QWidget *widget) const
    {
        QSize r= QProxyStyle::sizeFromContents(type, option, size, widget);
        qDebug() << __FUNCTION__ << size << "type=" << type
                 << DebugStyle::debugQStyleOption(option) << DebugStyle::debugWidget(widget) << "returns" << r;
        return r;
    }

    QRect subElementRect(SubElement element, const QStyleOption *option, const QWidget *widget) const
    {
        QRect r = QProxyStyle::subElementRect(element, option, widget);
        qDebug() << __FUNCTION__ << "element=" << element
                 << DebugStyle::debugQStyleOption(option) << DebugStyle::debugWidget(widget) << "returns" << r;
        return r;

    }
    QRect subControlRect(ComplexControl cc, const QStyleOptionComplex *opt, SubControl sc, const QWidget *widget) const
    {
        QRect r = QProxyStyle::subControlRect(cc, opt, sc, widget);
        qDebug() << __FUNCTION__ << "cc=" << cc << "sc=" << sc
                 <<  DebugStyle::debugQStyleOption(opt) << DebugStyle::debugWidget(widget) << "returns" << r;
        return r;
    }
    QRect itemTextRect(const QFontMetrics &fm, const QRect &r, int flags, bool enabled, const QString &text) const
    {
        QRect re = QProxyStyle::itemTextRect(fm, r, flags, enabled, text);
        qDebug() << __FUNCTION__ <<  r << "flags=" << flags  << "enabled=" << enabled << text << "returns " << re;
        return re;
    }

    QRect itemPixmapRect(const QRect &r, int flags, const QPixmap &pixmap) const
    {
        QRect re = QProxyStyle::itemPixmapRect(r, flags, pixmap);
        qDebug() << __FUNCTION__ << r << "flags=" << flags  << pixmap << "returns " << re;
        return re;
    }

    int pixelMetric(PixelMetric metric, const QStyleOption *option = 0, const QWidget *widget = 0) const
    {
        int r = QProxyStyle::pixelMetric(metric, option, widget);
        qDebug() << __FUNCTION__ << "metric="<< metric
                 << DebugStyle::debugQStyleOption(option) << DebugStyle::debugWidget(widget) << "returns" << r;
        return r;
    }

    QPixmap standardPixmap(StandardPixmap standardPixmap, const QStyleOption *opt, const QWidget *widget = 0) const
    {
        QPixmap r = QProxyStyle::standardPixmap(standardPixmap, opt, widget);
        qDebug() << __FUNCTION__ << "standardPixmap=" << standardPixmap << "returns " << r;
        return r;
    }

    QPixmap generatedIconPixmap(QIcon::Mode iconMode, const QPixmap &pixmap, const QStyleOption *opt) const
    {
        QPixmap r = QProxyStyle::generatedIconPixmap(iconMode, pixmap, opt);
        qDebug() << __FUNCTION__ << "iconMode=" << iconMode << pixmap << "returns " << r;
        return r;
    }
};

int main(int argc, char *argv[])
{
    QApplication app(argc, argv);    
    const QString stName = QApplication::style()->objectName();
    app.setStyle(new DebugStyle(QApplication::style()));

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