Source/WebCore/layout/integration/LayoutIntegrationInlineContentBuilder.cpp

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#include "config.h"
#include "LayoutIntegrationInlineContentBuilder.h"

#if ENABLE(LAYOUT_FORMATTING_CONTEXT)

#include "InlineDisplayBox.h"
#include "InlineFormattingState.h"
#include "LayoutBoxGeometry.h"
#include "LayoutIntegrationBoxTree.h"
#include "LayoutIntegrationInlineContent.h"
#include "LayoutReplacedBox.h"
#include "LayoutState.h"
#include "RenderBlockFlow.h"
#include "StringTruncator.h"

namespace WebCore {
namespace LayoutIntegration {

inline InlineDisplay::Line::EnclosingTopAndBottom operator+(const InlineDisplay::Line::EnclosingTopAndBottom enclosingTopAndBottom, float offset)
{
    return { enclosingTopAndBottom.top + offset, enclosingTopAndBottom.bottom + offset };
}

inline static float lineOverflowWidth(const RenderBlockFlow& flow, Layout::InlineLayoutUnit lineContentWidth)
{
    // FIXME: It's the copy of the lets-adjust-overflow-for-the-caret behavior from LegacyLineLayout::addOverflowFromInlineChildren.
    auto endPadding = flow.hasNonVisibleOverflow() ? flow.paddingEnd() : 0_lu;
    if (!endPadding)
        endPadding = flow.endPaddingWidthForCaret();
    if (flow.hasNonVisibleOverflow() && !endPadding && flow.element() && flow.element()->isRootEditableElement())
        endPadding = 1;
    return lineContentWidth + endPadding;
}

InlineContentBuilder::InlineContentBuilder(const RenderBlockFlow& blockFlow, BoxTree& boxTree)
    : m_blockFlow(blockFlow)
    , m_boxTree(boxTree)
{
}

void InlineContentBuilder::build(Layout::InlineFormattingState& inlineFormattingState, InlineContent& inlineContent) const
{
    // FIXME: This might need a different approach with partial layout where the layout code needs to know about the boxes.
    inlineContent.boxes = WTFMove(inlineFormattingState.boxes());

    auto updateIfTextRenderersNeedVisualReordering = [&] {
        // FIXME: We may want to have a global, "is this a bidi paragraph" flag to avoid this loop for non-rtl, non-bidi content. 
        for (auto& displayBox : inlineContent.boxes) {
            auto& layoutBox = displayBox.layoutBox();
            if (!is<Layout::InlineTextBox>(layoutBox))
                continue;
            if (displayBox.bidiLevel() != UBIDI_DEFAULT_LTR) 
                downcast<RenderText>(m_boxTree.rendererForLayoutBox(layoutBox)).setNeedsVisualReordering();
        }
    };
    updateIfTextRenderersNeedVisualReordering();
    createDisplayLines(inlineFormattingState, inlineContent);
}

void InlineContentBuilder::createDisplayLines(Layout::InlineFormattingState& inlineFormattingState, InlineContent& inlineContent) const
{
    auto& lines = inlineFormattingState.lines();
    auto& boxes = inlineContent.boxes;
    size_t boxIndex = 0;
    inlineContent.lines.reserveInitialCapacity(lines.size());
    for (size_t lineIndex = 0; lineIndex < lines.size(); ++lineIndex) {
        auto& line = lines[lineIndex];
        auto scrollableOverflowRect = FloatRect { line.scrollableOverflow() };
        if (auto overflowWidth = lineOverflowWidth(m_blockFlow, line.contentWidth()); overflowWidth > scrollableOverflowRect.width()) {
            auto overflowValue = overflowWidth - scrollableOverflowRect.width();
            m_blockFlow.style().isLeftToRightDirection() ? scrollableOverflowRect.shiftMaxXEdgeBy(overflowValue) : scrollableOverflowRect.shiftXEdgeBy(-overflowValue);
        }

        auto firstBoxIndex = boxIndex;
        auto lineInkOverflowRect = scrollableOverflowRect;
        // Collect overflow from boxes.
        for (; boxIndex < boxes.size() && boxes[boxIndex].lineIndex() == lineIndex; ++boxIndex) {
            auto& box = boxes[boxIndex];

            lineInkOverflowRect.unite(box.inkOverflow());

            auto& layoutBox = box.layoutBox();
            if (layoutBox.isReplacedBox()) {
                // Similar to LegacyInlineFlowBox::addReplacedChildOverflow.
                auto& renderer = downcast<RenderBox>(m_boxTree.rendererForLayoutBox(layoutBox));
                if (!renderer.hasSelfPaintingLayer()) {
                    auto childInkOverflow = renderer.logicalVisualOverflowRectForPropagation(&renderer.parent()->style());
                    childInkOverflow.move(box.left(), box.top());
                    lineInkOverflowRect.unite(childInkOverflow);
                }
                auto childScrollableOverflow = renderer.logicalLayoutOverflowRectForPropagation(&renderer.parent()->style());
                childScrollableOverflow.move(box.left(), box.top());
                scrollableOverflowRect.unite(childScrollableOverflow);
            }
        }

        if (!inlineContent.lines.isEmpty()) {
            auto& lastInkOverflow = inlineContent.lines.last().inkOverflow();
            if (lineInkOverflowRect.y() <= lastInkOverflow.y() || lastInkOverflow.maxY() >= lineInkOverflowRect.maxY())
                inlineContent.hasMultilinePaintOverlap = true;
        }

        auto boxCount = boxIndex - firstBoxIndex;
        inlineContent.lines.append({ firstBoxIndex, boxCount, FloatRect { line.lineBoxRect() }, line.enclosingTopAndBottom().top, line.enclosingTopAndBottom().bottom, scrollableOverflowRect, lineInkOverflowRect, line.baseline(), line.contentLeft(), line.contentWidth() });
    }
}

}
}

#endif