public void OnEdit()
{
if (!picture.shapes.Any(shape => shape is CompoundShape))
{
ToUndoStack.Push(new List <IShape>(picture.shapes.Select(shape => shape.Clone()).ToList()));
}
else
{
var cloneList = new List <IShape>();
foreach (var shape in picture.shapes)
{
if (shape is CompoundShape compoundShape)
{
cloneList.Add(GetAllCompoundShapeClones(compoundShape));
}
else
{
cloneList.Add(shape.Clone());
}
}
ToUndoStack.Push(cloneList);
}
ToRedoStack = new Stack <List <IShape> >();
}
public List <IShape> OnRedo()
{
if (ToRedoStack.Count != 0 && ToRedoStack.Any())
{
var copy = ToRedoStack.Peek().Select(shape =>
shape is CompoundShape compoundShape ? GetAllCompoundShapeClones(compoundShape) : shape.Clone()
).ToList();
ToUndoStack.Push(ToRedoStack.Pop());
return(copy);
}
return(null);
}
public List <IShape> OnUndo()
{
if (!IsStackEmpty())
{
ToRedoStack.Push(ToUndoStack.Pop());
var copy = ToUndoStack.Peek().Select(shape =>
shape is CompoundShape compoundShape ? GetAllCompoundShapeClones(compoundShape) : shape.Clone()
).ToList();
return(copy);
}
return(null);
}
private bool IsStackEmpty()
{
return(ToUndoStack.Count == 1 && ToUndoStack.Peek().Count == 0);
}
