private void StepForwardImpl()
{
HistoryMemento topMemento = redoStack[0];
ToolHistoryMemento asToolHistoryMemento = topMemento as ToolHistoryMemento;
if (asToolHistoryMemento != null && asToolHistoryMemento.ToolType != this.documentWorkspace.GetToolType())
{
this.documentWorkspace.SetToolFromType(asToolHistoryMemento.ToolType);
StepForward();
}
else
{
OnChanging();
ExecutingHistoryMementoEventArgs ehaea1 = new ExecutingHistoryMementoEventArgs(topMemento, true, false);
if (asToolHistoryMemento == null && topMemento.SeriesGuid != Guid.Empty)
{
ehaea1.SuspendTool = true;
}
OnExecutingHistoryMemento(ehaea1);
if (ehaea1.SuspendTool)
{
this.documentWorkspace.PushNullTool();
}
HistoryMemento redoMemento = redoStack[0];
// Possibly useful invariant here:
// ehaea1.HistoryMemento.SeriesGuid == ehaea2.HistoryMemento.SeriesGuid == ehaea3.HistoryMemento.SeriesGuid
ExecutingHistoryMementoEventArgs ehaea2 = new ExecutingHistoryMementoEventArgs(redoMemento, false, ehaea1.SuspendTool);
OnExecutingHistoryMemento(ehaea2);
HistoryMemento undoMemento = redoMemento.PerformUndo();
redoStack.RemoveAt(0);
undoStack.Add(undoMemento);
ExecutedHistoryMementoEventArgs ehaea3 = new ExecutedHistoryMementoEventArgs(undoMemento);
OnExecutedHistoryMemento(ehaea3);
OnChanged();
OnSteppedForward();
undoMemento.Flush();
if (ehaea1.SuspendTool)
{
this.documentWorkspace.PopNullTool();
}
}
if (this.stepGroupDepth == 0)
{
OnFinishedStepGroup();
}
}
/// <summary>
/// When the user does something new, it will clear out the redo stack.
/// </summary>
public void PushNewMemento(HistoryMemento value)
{
Utility.GCFullCollect();
OnChanging();
ClearRedoStack();
undoStack.Add(value);
OnNewHistoryMemento();
OnChanged();
value.Flush();
Utility.GCFullCollect();
}