third_party/blink/renderer/platform/text/text_run_iterator.h

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#ifndef THIRD_PARTY_BLINK_RENDERER_PLATFORM_TEXT_TEXT_RUN_ITERATOR_H_
#define THIRD_PARTY_BLINK_RENDERER_PLATFORM_TEXT_TEXT_RUN_ITERATOR_H_

#include "third_party/blink/renderer/platform/text/text_run.h"
#include "third_party/blink/renderer/platform/wtf/allocator.h"

namespace blink {

class TextRunIterator {
  DISALLOW_NEW();

 public:
  TextRunIterator() : text_run_(nullptr), offset_(0), length_(0) {}

  TextRunIterator(const TextRun* text_run, unsigned offset)
      : text_run_(text_run), offset_(offset), length_(text_run_->length()) {}

  TextRunIterator(const TextRunIterator& other)
      : text_run_(other.text_run_),
        offset_(other.offset_),
        length_(text_run_->length()) {}

  unsigned Offset() const { return offset_; }
  void Increment() { offset_++; }
  bool AtEnd() const { return offset_ >= length_; }
  UChar Current() const { return (*text_run_)[offset_]; }
  WTF::unicode::CharDirection Direction() const {
    return AtEnd() ? WTF::unicode::kOtherNeutral
                   : WTF::unicode::Direction(Current());
  }
  bool AtParagraphSeparator() const { return Current() == '\n'; }

  bool operator==(const TextRunIterator& other) {
    return offset_ == other.offset_ && text_run_ == other.text_run_;
  }

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

 private:
  const TextRun* text_run_;
  unsigned offset_;
  unsigned length_;
};

}  // namespace blink

#endif  // THIRD_PARTY_BLINK_RENDERER_PLATFORM_TEXT_TEXT_RUN_ITERATOR_H_