Use proper color for highlighted text in log widget

The color is either from qbt theme pack or desktop environment.

Note that Windows default theme do not use highlighted text color.
Other themes (either OS default or qbt themes) are closer to native
look when highlighted text color is in action.

src/gui/log/loglistview.cpp

@@ -29,6 +29,7 @@
 
 #include "loglistview.h"
 
+#include <QtGlobal>
 #include <QApplication>
 #include <QClipboard>
 #include <QFontMetrics>
@@ -38,9 +39,12 @@
 #include <QStyledItemDelegate>
 
 #include "base/global.h"
-#include "gui/uithememanager.h"
 #include "logmodel.h"
 
+#ifdef Q_OS_WIN
+#include "base/preferences.h"
+#endif
+
 namespace
 {
     const QString SEPARATOR = u" - "_qs;
@@ -60,7 +64,13 @@ namespace
     class LogItemDelegate final : public QStyledItemDelegate
     {
     public:
-        using QStyledItemDelegate::QStyledItemDelegate;
+        explicit LogItemDelegate(QObject *parent = nullptr)
+            : QStyledItemDelegate(parent)
+#ifdef Q_OS_WIN
+            , m_useCustomUITheme(Preferences::instance()->useCustomUITheme())
+#endif
+        {
+        }
 
     private:
         void paint(QPainter *painter, const QStyleOptionViewItem &option, const QModelIndex &index) const override
@@ -70,6 +80,16 @@ namespace
 
             const QStyle *style = option.widget ? option.widget->style() : QApplication::style();
             const QRect textRect = option.rect.adjusted(1, 0, 0, 0); // shift 1 to avoid text being too close to focus rect
+            const bool isEnabled = option.state.testFlag(QStyle::State_Enabled);
+
+#ifdef Q_OS_WIN
+            // Windows default theme do not use highlighted text color
+            const QPalette::ColorRole textRole = m_useCustomUITheme
+                ? (option.state.testFlag(QStyle::State_Selected) ? QPalette::HighlightedText : QPalette::WindowText)
+                : QPalette::WindowText;
+#else
+            const QPalette::ColorRole textRole = option.state.testFlag(QStyle::State_Selected) ? QPalette::HighlightedText : QPalette::WindowText;
+#endif
 
             // for unknown reasons (fixme) painter won't accept some font properties
             // until they are set explicitly, and we have to manually set some font properties
@@ -79,24 +99,23 @@ namespace
                 font.setPointSizeF(option.font.pointSizeF());
             painter->setFont(font);
 
-            const QPen originalPen = painter->pen();
-            QPen coloredPen = originalPen;
-            coloredPen.setColor(index.data(BaseLogModel::TimeForegroundRole).value<QColor>());
-            painter->setPen(coloredPen);
+            QPalette palette = option.palette;
+
             const QString time = index.data(BaseLogModel::TimeRole).toString();
-            style->drawItemText(painter, textRect, option.displayAlignment, option.palette, (option.state & QStyle::State_Enabled), time);
+            palette.setColor(QPalette::Active, QPalette::WindowText, index.data(BaseLogModel::TimeForegroundRole).value<QColor>());
+            style->drawItemText(painter, textRect, option.displayAlignment, palette, isEnabled, time, textRole);
 
-            painter->setPen(originalPen);
             const QFontMetrics fontMetrics = painter->fontMetrics(); // option.fontMetrics adds extra padding to QFontMetrics::width
             const int separatorCoordinateX = horizontalAdvance(fontMetrics, time);
             style->drawItemText(painter, textRect.adjusted(separatorCoordinateX, 0, 0, 0), option.displayAlignment, option.palette
-                                , (option.state & QStyle::State_Enabled), SEPARATOR);
+                                , isEnabled, SEPARATOR, textRole);
 
-            coloredPen.setColor(index.data(BaseLogModel::MessageForegroundRole).value<QColor>());
-            painter->setPen(coloredPen);
             const int messageCoordinateX = separatorCoordinateX + horizontalAdvance(fontMetrics, SEPARATOR);
-            style->drawItemText(painter, textRect.adjusted(messageCoordinateX, 0, 0, 0), option.displayAlignment, option.palette
-                                , (option.state & QStyle::State_Enabled), index.data(BaseLogModel::MessageRole).toString());
+            const QString message = index.data(BaseLogModel::MessageRole).toString();
+            palette.setColor(QPalette::Active, QPalette::WindowText, index.data(BaseLogModel::MessageForegroundRole).value<QColor>());
+            style->drawItemText(painter, textRect.adjusted(messageCoordinateX, 0, 0, 0), option.displayAlignment, palette
+                                , isEnabled, message, textRole);
+
             painter->restore();
         }
 
@@ -108,6 +127,10 @@ namespace
             const QSize margins = (defaultSize - fontSize).expandedTo({0, 0});
             return fontSize + margins;
         }
+
+#ifdef Q_OS_WIN
+        const bool m_useCustomUITheme = false;
+#endif
     };
 }
 
@@ -117,7 +140,7 @@ LogListView::LogListView(QWidget *parent)
     setSelectionMode(QAbstractItemView::ExtendedSelection);
     setItemDelegate(new LogItemDelegate(this));
 
-#if defined(Q_OS_MAC)
+#ifdef Q_OS_MAC
     setAttribute(Qt::WA_MacShowFocusRect, false);
 #endif
 }