Source/core/editing/UndoStack.h

/*
 * Copyright (C) 2009 Google 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 are
 * met:
 *
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 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
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 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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#ifndef UndoStack_h
#define UndoStack_h

#include "platform/heap/Handle.h"
#include "wtf/Deque.h"
#include "wtf/Forward.h"

namespace blink {

class LocalFrame;
class UndoStep;

class UndoStack final : public NoBaseWillBeGarbageCollected<UndoStack> {
    DECLARE_EMPTY_DESTRUCTOR_WILL_BE_REMOVED(UndoStack)
public:
    static PassOwnPtrWillBeRawPtr<UndoStack> create();

    void registerUndoStep(PassRefPtrWillBeRawPtr<UndoStep>);
    void registerRedoStep(PassRefPtrWillBeRawPtr<UndoStep>);
    void didUnloadFrame(const LocalFrame&);
    bool canUndo() const;
    bool canRedo() const;
    void undo();
    void redo();

    DECLARE_TRACE();

private:
    UndoStack();

    typedef WillBeHeapDeque<RefPtrWillBeMember<UndoStep>> UndoStepStack;

    void filterOutUndoSteps(UndoStepStack&, const LocalFrame&);

    bool m_inRedo;
    UndoStepStack m_undoStack;
    UndoStepStack m_redoStack;
};

} // namespace blink

#endif