private void Evaluate(XmlTextWriter output, RuleCondition <RuleContext> condition, RuleContext ruleContext, RuleStack stack, Database database, XElement element)
{
var andCondition = condition as AndCondition <RuleContext>;
if (andCondition != null)
{
Evaluate(output, andCondition.LeftOperand, ruleContext, stack, database, element.Element(0));
if (!(bool)stack.Pop())
{
stack.Push(false);
}
else
{
Evaluate(output, andCondition.RightOperand, ruleContext, stack, database, element.Element(1));
}
return;
}
var orCondition = condition as OrCondition <RuleContext>;
if (orCondition != null)
{
Evaluate(output, orCondition.LeftOperand, ruleContext, stack, database, element.Element(0));
if ((bool)stack.Pop())
{
stack.Push(true);
}
else
{
Evaluate(output, orCondition.RightOperand, ruleContext, stack, database, element.Element(1));
}
return;
}
var notCondition = condition as NotCondition <RuleContext>;
if (notCondition != null)
{
Evaluate(output, notCondition.Operand, ruleContext, stack, database, element.Element(0));
var flag = (bool)stack.Pop();
stack.Push(!flag);
return;
}
condition.Evaluate(ruleContext, stack);
var text = condition.GetType().Name;
var conditionItem = database.GetItem(element.GetAttributeValue("id"));
if (conditionItem != null)
{
text = Expand(database, conditionItem["Text"], element);
}
var result = stack.Peek();
output.WriteElementString("entry", string.Format(" Condition \"{0}\" returned \"{1}\".", text, result.ToString()));
}