Source/WebCore/rendering/EllipsisBoxPainter.cpp

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#include "config.h"
#include "EllipsisBoxPainter.h"

#include "CSSPropertyNames.h"
#include "InlineIteratorTextBox.h"
#include "LineSelection.h"
#include "PaintInfo.h"
#include "RenderObjectDocument.h"
#include "RenderStyle+GettersInlines.h"
#include "RenderView.h"
#include "Settings.h"
#include "StyleColorResolver.h"
#include "StyleTextShadow.h"

namespace WebCore {

EllipsisBoxPainter::EllipsisBoxPainter(const InlineIterator::LineBox& lineBox, PaintInfo& paintInfo, const LayoutPoint& paintOffset, Color selectionForegroundColor, Color selectionBackgroundColor)
    : m_lineBox(lineBox)
    , m_paintInfo(paintInfo)
    , m_paintOffset(paintOffset)
    , m_selectionForegroundColor(selectionForegroundColor)
    , m_selectionBackgroundColor(selectionBackgroundColor)
{
}

void EllipsisBoxPainter::paint()
{
    // FIXME: Transition it to TextPainter.
    auto& context = m_paintInfo.context();
    auto& style = m_lineBox.style();
    auto textColor = style.visitedDependentTextFillColorApplyingColorFilter();

    if (m_paintInfo.forceTextColor())
        textColor = m_paintInfo.forcedTextColor();

    if (m_lineBox.ellipsisSelectionState() != RenderObject::HighlightState::None) {
        paintSelection();

        // Select the correct color for painting the text.
        auto foreground = m_paintInfo.forceTextColor() ? m_paintInfo.forcedTextColor() : m_selectionForegroundColor;
        if (foreground.isValid() && foreground != textColor)
            context.setFillColor(foreground);
    }

    if (textColor != context.fillColor())
        context.setFillColor(textColor);

    bool setShadow = WTF::switchOn(style.textShadow(),
        [&](const CSS::Keyword::None&) {
            return false;
        },
        [&](const auto& shadows) {
            const auto& zoomFactor = style.usedZoomForLength();

            Style::ColorResolver colorResolver { style };

            context.setDropShadow({
                LayoutSize {
                    shadows[0].location.x().resolveZoom(zoomFactor),
                    shadows[0].location.y().resolveZoom(zoomFactor),
                },
                shadows[0].blur.resolveZoom(zoomFactor),
                colorResolver.colorResolvingCurrentColorApplyingColorFilter(shadows[0].color),
                ShadowRadiusMode::Default
            });
            return true;
        }
    );

    auto visualRect = m_lineBox.ellipsisVisualRect();
    auto textOrigin = visualRect.location();
    auto ascent = m_lineBox.formattingContextRoot().settings().subpixelInlineLayoutEnabled() ? LayoutUnit(style.metricsOfPrimaryFont().ascent()) : LayoutUnit(style.metricsOfPrimaryFont().intAscent());
    textOrigin.move(m_paintOffset.x(), m_paintOffset.y() + ascent);

    if (style.writingMode().isHorizontal())
        textOrigin.setY(roundToDevicePixel(LayoutUnit { textOrigin.y() }, m_lineBox.formattingContextRoot().document().deviceScaleFactor()));
    else
        textOrigin.setX(roundToDevicePixel(LayoutUnit { textOrigin.x() }, m_lineBox.formattingContextRoot().document().deviceScaleFactor()));

    context.drawBidiText(style.fontCascade(), m_lineBox.ellipsisText(), textOrigin);

    if (textColor != context.fillColor())
        context.setFillColor(textColor);

    if (setShadow)
        context.clearDropShadow();
}

void EllipsisBoxPainter::paintSelection()
{
    auto& context = m_paintInfo.context();
    auto& style = m_lineBox.style();

    auto textColor = style.visitedDependentColorApplyingColorFilter();
    auto backgroundColor = m_selectionBackgroundColor;
    if (!backgroundColor.isVisible())
        return;

    // If the text color ends up being the same as the selection background, invert the selection background.
    if (textColor == backgroundColor)
        backgroundColor = backgroundColor.invertedColorWithAlpha(1.0);

    auto stateSaver = GraphicsContextStateSaver { context };

    auto visualRect = LayoutRect { m_lineBox.ellipsisVisualRect(InlineIterator::LineBox::AdjustedForSelection::Yes) };
    visualRect.move(m_paintOffset.x(), m_paintOffset.y());

    auto ellipsisText = m_lineBox.ellipsisText();
    constexpr bool canUseSimplifiedTextMeasuring = false;
    style.fontCascade().adjustSelectionRectForText(canUseSimplifiedTextMeasuring, ellipsisText, visualRect);
    context.fillRect(snapRectToDevicePixelsWithWritingDirection(visualRect, m_lineBox.formattingContextRoot().document().deviceScaleFactor(), ellipsisText.ltr()), backgroundColor);
}

}