sky/engine/platform/text/TextRunIterator.h

// Copyright (C) 2013 Google Inc. All rights reserved.
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#ifndef SKY_ENGINE_PLATFORM_TEXT_TEXTRUNITERATOR_H_
#define SKY_ENGINE_PLATFORM_TEXT_TEXTRUNITERATOR_H_

#include "sky/engine/platform/text/TextRun.h"

namespace blink {

class TextRunIterator {
public:
    TextRunIterator()
        : m_textRun(0)
        , m_offset(0)
    {
    }

    TextRunIterator(const TextRun* textRun, unsigned offset)
        : m_textRun(textRun)
        , m_offset(offset)
    {
    }

    TextRunIterator(const TextRunIterator& other)
        : m_textRun(other.m_textRun)
        , m_offset(other.m_offset)
    {
    }

    unsigned offset() const { return m_offset; }
    void increment() { m_offset++; }
    bool atEnd() const { return !m_textRun || m_offset >= m_textRun->length(); }
    UChar current() const { return (*m_textRun)[m_offset]; }
    WTF::Unicode::Direction direction() const { return atEnd() ? WTF::Unicode::OtherNeutral : WTF::Unicode::direction(current()); }
    bool atParagraphSeparator() const { return current() == '\n'; }

    bool operator==(const TextRunIterator& other)
    {
        return m_offset == other.m_offset && m_textRun == other.m_textRun;
    }

    bool operator!=(const TextRunIterator& other) { return !operator==(other); }

private:
    const TextRun* m_textRun;
    int m_offset;
};


} // namespace blink

#endif  // SKY_ENGINE_PLATFORM_TEXT_TEXTRUNITERATOR_H_