Source/WebCore/editing/RenderedPosition.h

/*
 * Copyright (C) 2011 Google Inc. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
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 * notice, this list of conditions and the following disclaimer.
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 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
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 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#pragma once

#include "CaretRectComputation.h"
#include "InlineIteratorBox.h"
#include "InlineIteratorLineBox.h"
#include "TextAffinity.h"

namespace WebCore {

class LayoutUnit;
class Position;
class RenderObject;
class VisiblePosition;

class RenderedPosition {
public:
    RenderedPosition();
    explicit RenderedPosition(const VisiblePosition&);
    explicit RenderedPosition(const Position&, Affinity);
    bool isEquivalent(const RenderedPosition&) const;

    bool isNull() const { return !m_renderer; }
    InlineIterator::LineBoxIterator lineBox() const { return m_box ? m_box->lineBox() : InlineIterator::LineBoxIterator(); }

    unsigned char bidiLevelOnLeft() const;
    unsigned char bidiLevelOnRight() const;
    RenderedPosition leftBoundaryOfBidiRun(unsigned char bidiLevelOfRun);
    RenderedPosition rightBoundaryOfBidiRun(unsigned char bidiLevelOfRun);

    enum ShouldMatchBidiLevel { MatchBidiLevel, IgnoreBidiLevel };
    bool atLeftBoundaryOfBidiRun() const { return atLeftBoundaryOfBidiRun(IgnoreBidiLevel, 0); }
    bool atRightBoundaryOfBidiRun() const { return atRightBoundaryOfBidiRun(IgnoreBidiLevel, 0); }
    // The following two functions return true only if the current position is at the end of the bidi run
    // of the specified bidi embedding level.
    bool atLeftBoundaryOfBidiRun(unsigned char bidiLevelOfRun) const { return atLeftBoundaryOfBidiRun(MatchBidiLevel, bidiLevelOfRun); }
    bool atRightBoundaryOfBidiRun(unsigned char bidiLevelOfRun) const { return atRightBoundaryOfBidiRun(MatchBidiLevel, bidiLevelOfRun); }

    Position positionAtLeftBoundaryOfBiDiRun() const;
    Position positionAtRightBoundaryOfBiDiRun() const;

    IntRect absoluteRect(CaretRectMode = CaretRectMode::Normal) const;

private:
    bool operator==(const RenderedPosition&) const { return false; }
    explicit RenderedPosition(const RenderObject*, InlineIterator::LeafBoxIterator, unsigned offset);

    InlineIterator::LeafBoxIterator previousLeafOnLine() const;
    InlineIterator::LeafBoxIterator nextLeafOnLine() const;
    bool atLeftmostOffsetInBox() const { return m_box && m_offset == m_box->leftmostCaretOffset(); }
    bool atRightmostOffsetInBox() const { return m_box && m_offset == m_box->rightmostCaretOffset(); }
    bool atLeftBoundaryOfBidiRun(ShouldMatchBidiLevel, unsigned char bidiLevelOfRun) const;
    bool atRightBoundaryOfBidiRun(ShouldMatchBidiLevel, unsigned char bidiLevelOfRun) const;

    const RenderObject* m_renderer { nullptr };
    InlineIterator::LeafBoxIterator m_box;
    unsigned m_offset { 0 };

    mutable std::optional<InlineIterator::LeafBoxIterator> m_previousLeafOnLine;
    mutable std::optional<InlineIterator::LeafBoxIterator> m_nextLeafOnLine;
};

bool renderObjectContainsPosition(const RenderObject*, const Position&);

} // namespace WebCore