third_party/WebKit/Source/core/layout/line/AbstractInlineTextBox.h

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#ifndef AbstractInlineTextBox_h
#define AbstractInlineTextBox_h

#include "core/CoreExport.h"
#include "core/dom/Range.h"
#include "core/layout/api/LineLayoutText.h"
#include "core/layout/line/InlineTextBox.h"
#include "wtf/HashMap.h"
#include "wtf/RefCounted.h"
#include "wtf/RefPtr.h"

namespace blink {

class InlineTextBox;

// High-level abstraction of InlineTextBox to allow the accessibility module to
// get information about InlineTextBoxes without tight coupling.
class CORE_EXPORT AbstractInlineTextBox
    : public RefCounted<AbstractInlineTextBox> {
 private:
  AbstractInlineTextBox(LineLayoutText lineLayoutItem,
                        InlineTextBox* inlineTextBox)
      : m_lineLayoutItem(lineLayoutItem), m_inlineTextBox(inlineTextBox) {}

  static PassRefPtr<AbstractInlineTextBox> getOrCreate(LineLayoutText,
                                                       InlineTextBox*);
  static void willDestroy(InlineTextBox*);

  friend class LayoutText;
  friend class InlineTextBox;

 public:
  struct WordBoundaries {
    DISALLOW_NEW_EXCEPT_PLACEMENT_NEW();
    WordBoundaries(int startIndex, int endIndex)
        : startIndex(startIndex), endIndex(endIndex) {}
    int startIndex;
    int endIndex;
  };

  enum Direction { LeftToRight, RightToLeft, TopToBottom, BottomToTop };

  ~AbstractInlineTextBox();

  LineLayoutText getLineLayoutItem() const { return m_lineLayoutItem; }

  PassRefPtr<AbstractInlineTextBox> nextInlineTextBox() const;
  LayoutRect localBounds() const;
  unsigned len() const;
  Direction getDirection() const;
  void characterWidths(Vector<float>&) const;
  void wordBoundaries(Vector<WordBoundaries>&) const;
  String text() const;
  bool isFirst() const;
  bool isLast() const;
  PassRefPtr<AbstractInlineTextBox> nextOnLine() const;
  PassRefPtr<AbstractInlineTextBox> previousOnLine() const;

 private:
  void detach();

  // Weak ptrs; these are nulled when InlineTextBox::destroy() calls
  // AbstractInlineTextBox::willDestroy.
  LineLayoutText m_lineLayoutItem;
  InlineTextBox* m_inlineTextBox;

  typedef HashMap<InlineTextBox*, RefPtr<AbstractInlineTextBox>>
      InlineToAbstractInlineTextBoxHashMap;
  static InlineToAbstractInlineTextBoxHashMap* gAbstractInlineTextBoxMap;
};

}  // namespace blink

#endif  // AbstractInlineTextBox_h