Undo.h

// Copyright (C), UNIGINE. All rights reserved.
#pragma once


#include <EditorGlobal.h>
#include <QObject>


// Forward decl.
namespace Editor
{
class Presenter;
class Action;
}


namespace Editor
{
class EDITOR_API Undo : public QObject
{
    Q_OBJECT
public:
    static Undo *instance();

    static void apply(Action *action);
    static void push(Action *action);
    static void undo();
    static void redo();

    static void reset();
    static void begin();
    static void commit();
    static void rollback();

signals:
    void worldModified();
    void activity();

private:
    explicit Undo(QObject *parent);
    ~Undo() override;

    friend class Editor::Presenter;
};

class EDITOR_API Action
{
public:
    Action();
    virtual ~Action();
    virtual void apply() = 0;
    virtual void undo()  = 0;
    virtual void redo()  = 0;

    virtual bool validate() { return true; }
    virtual bool modifiesWorld() const { return true; }
};


} // namespace Editor