InlineTextItem.h   [plain text]


/*
 * Copyright (C) 2018 Apple 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
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 *
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 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
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 */

#pragma once

#if ENABLE(LAYOUT_FORMATTING_CONTEXT)

#include "InlineFormattingState.h"
#include "InlineItem.h"
#include "LayoutInlineTextBox.h"

namespace WebCore {
namespace Layout {

class InlineTextItem : public InlineItem {
public:
    static void createAndAppendTextItems(InlineItems&, const InlineTextBox&);

    unsigned start() const { return m_startOrPosition; }
    unsigned end() const { return start() + length(); }
    unsigned length() const { return m_length; }

    bool isWhitespace() const { return m_textItemType == TextItemType::Whitespace; }
    bool isCollapsible() const { return m_isCollapsible; }
    Optional<InlineLayoutUnit> width() const { return m_hasWidth ? makeOptional(m_width) : Optional<InlineLayoutUnit> { }; }
    bool isEmptyContent() const;

    const InlineTextBox& inlineTextBox() const { return downcast<InlineTextBox>(layoutBox()); }

    InlineTextItem left(unsigned length) const;
    InlineTextItem right(unsigned length) const;

private:
    using InlineItem::TextItemType;

    InlineTextItem(const InlineTextBox&, unsigned start, unsigned length, Optional<InlineLayoutUnit> width, TextItemType);
    InlineTextItem(const InlineTextBox&);

    static InlineTextItem createWhitespaceItem(const InlineTextBox&, unsigned start, unsigned length, Optional<InlineLayoutUnit> width);
    static InlineTextItem createNonWhitespaceItem(const InlineTextBox&, unsigned start, unsigned length, Optional<InlineLayoutUnit> width);
    static InlineTextItem createEmptyItem(const InlineTextBox&);
};

inline InlineTextItem InlineTextItem::createWhitespaceItem(const InlineTextBox& inlineTextBox, unsigned start, unsigned length, Optional<InlineLayoutUnit> width)
{
    return { inlineTextBox, start, length, width, TextItemType::Whitespace };
}

inline InlineTextItem InlineTextItem::createNonWhitespaceItem(const InlineTextBox& inlineTextBox, unsigned start, unsigned length, Optional<InlineLayoutUnit> width)
{
    return { inlineTextBox, start, length, width, TextItemType::NonWhitespace };
}

inline InlineTextItem InlineTextItem::createEmptyItem(const InlineTextBox& inlineTextBox)
{
    return { inlineTextBox };
}

inline InlineTextItem::InlineTextItem(const InlineTextBox& inlineTextBox, unsigned start, unsigned length, Optional<InlineLayoutUnit> width, TextItemType textItemType)
    : InlineItem(inlineTextBox, Type::Text)
{
    m_startOrPosition = start;
    m_length = length;
    m_hasWidth = !!width;
    m_isCollapsible = textItemType == TextItemType::Whitespace && inlineTextBox.style().collapseWhiteSpace();
    m_width = width.valueOr(0);
    m_textItemType = textItemType;
}

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

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

inline InlineTextItem InlineTextItem::right(unsigned length) const
{
    RELEASE_ASSERT(length <= this->length());
    ASSERT(m_textItemType != TextItemType::Undefined);
    ASSERT(length);
    return { inlineTextBox(), end() - length, length, WTF::nullopt, m_textItemType };
}

}
}

SPECIALIZE_TYPE_TRAITS_INLINE_ITEM(InlineTextItem, isText())

#endif