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** Copyright (C) 2002 NVIDIA Corporation.
** Copyright (C) 2017 The Qt Company Ltd.
** Contact: https://www.qt.io/licensing/
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** This file is part of Qt 3D Studio.
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** General Public License version 3 as published by the Free Software
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#ifndef INCLUDED_CMD_STACK_H
#define INCLUDED_CMD_STACK_H 1

#pragma once

#include "Qt3DSString.h"

class CCmd;
class ICmdStackModifier;

//=============================================================================
/**
 * Class to listen for changes on the command listener.
 */
//=============================================================================
class CModificationListener
{
public:
    //==========================================================================
    /**
     * This is called every time a command is executed which modifies the
     * modified flag on the command stack. It is used to notify the interested
     * document that a change has occurred.
     */
    //==========================================================================
    virtual void SetCommandModifiedFlag(bool inModified) = 0;

    //==========================================================================
    /**
     * Called when a command modifies one or more of the views and the views
     * need to be redrawn.
     *
     * @param inUpdateFlags flags of what needs to be redrawn.
     */
    //==========================================================================
    virtual void CommandUpdate(unsigned long inUpdateFlags) = 0;
};

class CCmdStack
{
public:
    typedef std::vector<CCmd *> TCmdList;

    CCmdStack();
    virtual ~CCmdStack();

    bool ExecuteCommand(CCmd *inCommand);
    void Undo();
    void Redo();

    bool CanUndo();
    bool CanRedo();

    bool isUndoingOrRedoing() const;

    void RemoveLastUndo();

    QString GetUndoDescription();
    QString GetRedoDescription();

    void CommitLastCommand();

    void Clear();
    void ClearInvalid();

    void SetCommandStackModifier(ICmdStackModifier *inModifier);
    void SetModificationListener(CModificationListener *inListener);

    TCmdList GetUndoStack();
    TCmdList GetRedoStack();
    void EmptyRedoStack();

protected:
    void EmptyUndoStack();

    ICmdStackModifier *m_CommandStackModifier = nullptr;

    TCmdList m_UndoList;
    TCmdList m_RedoList;

    bool m_undoingOrRedoing = false;

    unsigned long m_MaxUndoStackSize = 100;

    CModificationListener *m_Listener = nullptr;
};
#endif // INCLUDED_CMD_STACK_H