Source/WebCore/layout/formattingContexts/inline/invalidation/InlineDamage.h

/*
 * Copyright (C) 2021 Apple Inc. All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
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 */

#pragma once

#if ENABLE(LAYOUT_FORMATTING_CONTEXT)

#include <wtf/IsoMallocInlines.h>

namespace WebCore {
namespace Layout {

class InlineInvalidation;

class InlineDamage {
    WTF_MAKE_ISO_ALLOCATED_INLINE(InlineDamage);
public:
    InlineDamage() = default;

    enum class Type {
        // Content changed or some style property that drives soft wrap opportunities (e.g. going from white-space: pre to normal).
        // This tells us to re-process the inline content and run line layout.
        NeedsContentUpdateAndLineLayout,
        // Same content but either the constraint or some style that may affect line breaking changed (e.g. font-size or containing block set new horizontal constraint). 
        NeedsLineLayout,
        // Line breaking positions are the same, only height related style changed (e.g img's height changes).
        NeedsVerticalAdjustment,
        // Line breaking positions are the same, runs may show up at a different horizontal position (e.g. text-align changes).
        NeedsHorizontalAdjustment 
    };
    Type type() const { return m_damageType; }
    // FIXME: Add support for damage range with multiple, different damage types.
    std::optional<size_t> line() const { return m_damagedLine; }

private:
    friend class InlineInvalidation;

    void setDamageType(Type type) { m_damageType = type; }
    void setDamagedLine(size_t lineIndex) { m_damagedLine = lineIndex; }

    Type m_damageType { Type::NeedsContentUpdateAndLineLayout };
    std::optional<size_t> m_damagedLine;
};

}
}
#endif