source: branches/HeuristicLab.Problems.GrammaticalOptimization/DynamicDataDisplay/Common/UndoSystem/ActionStack.cs @ 13348

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Diagnostics;

namespace Microsoft.Research.DynamicDataDisplay.Common.UndoSystem
{
  [DebuggerDisplay("Count = {Count}")]
  public sealed class ActionStack
  {
    private readonly Stack<UndoAction> stack = new Stack<UndoAction>();

    public void Push(UndoAction action)
    {
      stack.Push(action);

      if (stack.Count == 1)
        RaiseIsEmptyChanged();
    }

    public UndoAction Pop()
    {
      var action = stack.Pop();

      if (stack.Count == 0)
        RaiseIsEmptyChanged();

      return action;
    }

    public int Count { get { return stack.Count; } }

    public void Clear()
    {
      stack.Clear();
      RaiseIsEmptyChanged();
    }

    public bool IsEmpty
    {
      get { return stack.Count == 0; }
    }

    private void RaiseIsEmptyChanged()
    {
      IsEmptyChanged.Raise(this);
    }
    public event EventHandler IsEmptyChanged;
  }
}