public IDisposable Initialize()
{
var groups = _allNodes.GroupBy(item => item.Value, item => item.Key).ToArray();
foreach (var group in groups)
{
switch (group.Key)
{
case NodeType.IfTrue:
_ifTrueNodes = group.ToList().AsReadOnly();
break;
case NodeType.IfFalse:
_ifFalseNodes = group.ToList().AsReadOnly();
break;
case NodeType.Test:
group.ForEach(item => item.Changed += OnChanged);
break;
}
}
var ifTrueChildDisposable = IfTrueChild?.Initialize();
var ifFalseChildDisposable = IfFalseChild?.Initialize();
Update(true);
return(Disposable.Create(() =>
{
Update(false);
_ifTrueNodes = null;
_ifFalseNodes = null;
groups.FirstOrDefault(item => item.Key == NodeType.Test)?
.ForEach(item => item.Changed -= OnChanged);
ifTrueChildDisposable?.Dispose();
ifFalseChildDisposable?.Dispose();
}));
}
private void Update(bool activate)
{
IsActivated = activate;
if (IsActivated)
{
var testResult = _testGetter.TryGet(out var exception);
if (exception == null)
{
UpdateInternal(IfTrueChild, _ifTrueNodes, testResult);
UpdateInternal(IfFalseChild, _ifFalseNodes, !testResult);
}
}
else
{
// Disable all nodes and child-conditional-expression recursively.
_allNodes.Keys.ForEach(item => item.IsActivated = false);
// The following two line only used to conditional expressions
// that are larger than three levels of nesting.
IfTrueChild?.Update(false);
IfFalseChild?.Update(false);
}
}
