using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        RunModel();

    }

    public static void RunModel()

    {

        List<UndoBatch> um = new List<UndoBatch>();

        UndoBatch batch;

        batch = new UndoBatch();

        batch.AddUndoData( new ChangeQuantityUndoData() );

        batch.AddUndoData( new ChangeQuantityUndoData() );

        batch.AddUndoData( new ChangeQuantityUndoData() );

        um.Add(batch);

​

        batch = new UndoBatch();

        batch.AddUndoData( new ChangePriceUndoData() );

        batch.AddUndoData( new ChangePriceUndoData() );

        um.Add(batch);

​

        batch = new UndoBatch();

        batch.AddUndoData( new AddProductUndoData() );

        um.Add(batch);

​

        batch = new UndoBatch();

        DeleteProductUndoData dpud = new DeleteProductUndoData();

        dpud.DeletedElementRestoredEventHandler += (sender, e) => { Console.WriteLine("Undo: Restored Product = {0}", ((DeleteProductUndoData)e).originalId); };

        dpud.originalId = 2931;

        batch.AddUndoData( dpud );

        um.Add(batch);

        foreach (UndoBatch ub in um)

            ub.RunUndoBatch();

    }

    public static void OnDeletedElementRestored(object sender, DeleteProductUndoData e)

    {

        Console.WriteLine("Undo: Restored Product = {0}", e.originalId);

    }

}

​

public class UndoBatch

{

    private List<IUndoData> operationData;

    public UndoBatch()

    {

        operationData = new List<IUndoData>();

    }

    public void AddUndoData(IUndoData undoData)

    {

        operationData.Add(undoData);

    }

    public void RunUndoBatch()

    {

        foreach (IUndoData op in operationData)

            op.RunUndo();

    }

}

​

public class ChangeQuantityUndoData : IUndoData

{

    public void RunUndo()

    {

        Console.WriteLine("Undo: Change Quantity");

    }

}

​

public class ChangePriceUndoData : IUndoData

{

    public void RunUndo()

    {

        Console.WriteLine("Undo: Change Price");

    }

}

​

public class AddProductUndoData : IUndoData

{

    public void RunUndo()

    {

        Console.WriteLine("Undo: Add Product");

    }

}

​

public class DeleteProductUndoData : IUndoData

{

    public EventHandler<IUndoData> DeletedElementRestoredEventHandler;

​

    public void RunUndo()

    {

        Console.WriteLine("Undo: Delete Product");

        if (DeletedElementRestoredEventHandler != null)

            DeletedElementRestoredEventHandler.Invoke(this, this);

    }

    public int originalId { get; set; }

}

​

public interface IUndoData

{

    void RunUndo();

}