Source/WebCore/layout/formattingContexts/inline/InlineTextItem.cpp

/*
 * Copyright (C) 2018 Apple Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions
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 *
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 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
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#include "config.h"
#include "InlineTextItem.h"

#if ENABLE(LAYOUT_FORMATTING_CONTEXT)

#include "FontCascade.h"
#include "InlineSoftLineBreakItem.h"
#include "TextUtil.h"
#include <wtf/unicode/CharacterNames.h>

namespace WebCore {
namespace Layout {

static_assert(sizeof(InlineItem) == sizeof(InlineTextItem), "");

InlineTextItem::InlineTextItem(const InlineTextBox& inlineTextBox, unsigned start, unsigned length, UBiDiLevel bidiLevel, bool hasTrailingSoftHyphen, bool isWordSeparator, std::optional<InlineLayoutUnit> width, TextItemType textItemType)
    : InlineItem(inlineTextBox, Type::Text, bidiLevel)
{
    m_startOrPosition = start;
    m_length = length;
    m_hasWidth = !!width;
    m_hasTrailingSoftHyphen = hasTrailingSoftHyphen;
    m_isWordSeparator = isWordSeparator;
    m_width = width.value_or(0);
    m_textItemType = textItemType;
}

InlineTextItem::InlineTextItem(const InlineTextBox& inlineTextBox, UBiDiLevel bidiLevel)
    : InlineItem(inlineTextBox, Type::Text, bidiLevel)
{
}

InlineTextItem InlineTextItem::left(unsigned length) const
{
    RELEASE_ASSERT(length <= this->length());
    ASSERT(m_textItemType != TextItemType::Undefined);
    ASSERT(length);
    return { inlineTextBox(), start(), length, bidiLevel(), false, isWordSeparator(), std::nullopt, m_textItemType };
}

InlineTextItem InlineTextItem::right(unsigned length, std::optional<InlineLayoutUnit> width) const
{
    RELEASE_ASSERT(length <= this->length());
    ASSERT(m_textItemType != TextItemType::Undefined);
    ASSERT(length);
    return { inlineTextBox(), end() - length, length, bidiLevel(), hasTrailingSoftHyphen(), isWordSeparator(), width, m_textItemType };
}

InlineTextItem InlineTextItem::split(size_t leftSideLength)
{
    RELEASE_ASSERT(length() > 1);
    RELEASE_ASSERT(leftSideLength && leftSideLength < length());
    auto rightSide = right(length() - leftSideLength, { });
    m_length = length() - rightSide.length();
    m_hasWidth = false;
    m_width = { };
    return rightSide;
}

bool InlineTextItem::isZeroWidthSpaceSeparator() const
{
    // FIXME: We should check for more zero width content and not just U+200B.
    return !m_length || (m_length == 1 && inlineTextBox().content()[start()] == zeroWidthSpace); 
}

bool InlineTextItem::isCollapsibleNonBreakingSpace() const
{
    if (style().nbspMode() != NBSPMode::Space)
        return false;
    // Note that this text item may be longer than just one character.
    return m_length && inlineTextBox().content()[start()] == noBreakSpace;
}

bool InlineTextItem::shouldPreserveSpacesAndTabs(const InlineTextItem& inlineTextItem)
{
    ASSERT(inlineTextItem.isWhitespace());
    return TextUtil::shouldPreserveSpacesAndTabs(inlineTextItem.layoutBox());
}

}
}
#endif