public EventStackFilter()
{
var stackOnlyFields = _stackOnlyFields.Union(_stackOnlySpecialFields);
var stackFields = stackOnlyFields.Union(_stackAndEventFields);
_parser = new LuceneQueryParser();
_eventQueryVisitor = new ChainedQueryVisitor();
_eventQueryVisitor.AddVisitor(new RemoveFieldsQueryVisitor(stackOnlyFields));
_eventQueryVisitor.AddVisitor(new CleanupQueryVisitor());
_stackQueryVisitor = new ChainedQueryVisitor();
// remove everything not in the stack fields list
_stackQueryVisitor.AddVisitor(new RemoveFieldsQueryVisitor(f => !stackFields.Contains(f)));
_stackQueryVisitor.AddVisitor(new CleanupQueryVisitor());
// handles stack special fields and changing event field names to their stack equivalent
_stackQueryVisitor.AddVisitor(new StackFilterQueryVisitor());
_stackQueryVisitor.AddVisitor(new CleanupQueryVisitor());
_invertedStackQueryVisitor = new ChainedQueryVisitor();
// remove everything not in the stack fields list
_invertedStackQueryVisitor.AddVisitor(new RemoveFieldsQueryVisitor(f => !stackFields.Contains(f)));
_invertedStackQueryVisitor.AddVisitor(new CleanupQueryVisitor());
// handles stack special fields and changing event field names to their stack equivalent
_invertedStackQueryVisitor.AddVisitor(new StackFilterQueryVisitor());
_invertedStackQueryVisitor.AddVisitor(new CleanupQueryVisitor());
// inverts the filter
_invertedStackQueryVisitor.AddVisitor(new InvertQueryVisitor(_stackNonInvertedFields));
_invertedStackQueryVisitor.AddVisitor(new CleanupQueryVisitor());
}