private IExpression ProcessFilter(XElement elem, FilterSettings settings, PropertyReference prop)
{
var elemName = elem.Name.LocalName.ToLowerInvariant();
switch (elemName)
{
case "property":
return(settings.ItemCallback(elem.Attribute("query_items_xpath")?.Value)
.GetProperty(new[] { elem.Attribute("name")?.Value }));
case "constant":
if (long.TryParse(elem.Value, out var lng) ||
double.TryParse(elem.Value, out var dbl) ||
DateTime.TryParse(elem.Value, out var date))
{
return(new ObjectLiteral(elem.Value, prop, _context));
}
else if (elem.Value.IndexOf('$') >= 0)
{
return(ReplaceParameters(elem.Value));
}
else
{
return(new StringLiteral(elem.Value));
}
case "count":
var path = elem.Element("query_reference_path").Value.Split('/');
var result = new CountAggregate();
foreach (var table in path.Select(s => settings.Joins[s].Right))
{
result.TablePath.Add(table);
}
return(result);
case "eq":
case "ne":
case "gt":
case "ge":
case "lt":
case "le":
case "like":
var left = ProcessFilter(elem.Elements().First(), settings, prop);
var right = ProcessFilter(elem.Elements().ElementAt(1), settings, left as PropertyReference);
if (left is CountAggregate cnt &&
right is IntegerLiteral iLit &&
Parents(elem)
.All(p => string.Equals(p.Name.LocalName, "condition", StringComparison.OrdinalIgnoreCase) ||
string.Equals(p.Name.LocalName, "and", StringComparison.OrdinalIgnoreCase)) &&
((elemName == "gt" && iLit.Value == 0) ||
(elemName == "ge" && iLit.Value == 1)))
{
var refPath = elem.Element("count").Element("query_reference_path").Value.Split('/');
foreach (var join in refPath.Select(s => settings.Joins[s]))
{
join.Type = JoinType.Inner;
}
return(IgnoreNode.Instance);
}
switch (elemName)
{
case "eq":
return(new EqualsOperator()
{
Left = left, Right = right
}.Normalize());
case "ne":
return(new NotEqualsOperator()
{
Left = left, Right = right
}.Normalize());
case "gt":
return(new GreaterThanOperator()
{
Left = left, Right = right
}.Normalize());
case "ge":
return(new GreaterThanOrEqualsOperator()
{
Left = left, Right = right
}.Normalize());
case "lt":
return(new LessThanOperator()
{
Left = left, Right = right
}.Normalize());
case "le":
return(new LessThanOrEqualsOperator()
{
Left = left, Right = right
}.Normalize());
case "like":
right = AmlLikeParser.Instance.Parse(right.ToString());
return(new LikeOperator()
{
Left = left, Right = right
}.Normalize());
default:
throw new InvalidOperationException();
}
case "null":
return(new IsOperator()
{
Left = ProcessFilter(elem.Elements().First(), settings, prop),
Right = IsOperand.Null
}.Normalize());
case "and":
case "or":
var children = elem.Elements()
.Select(e => ProcessFilter(e, settings, prop))
.ToArray();
if (children.Length < 1)
{
throw new InvalidOperationException();
}
else if (children.Length == 1)
{
return(children[0]);
}
else if (string.Equals(elem.Name.LocalName, "and", StringComparison.OrdinalIgnoreCase))
{
var expr = new AndOperator()
{
Left = children[0],
Right = children[1]
}.Normalize();
for (var i = 2; i < children.Length; i++)
{
expr = new AndOperator()
{
Left = expr,
Right = children[i]
}.Normalize();
}
return(expr);
}
else if (string.Equals(elem.Name.LocalName, "or", StringComparison.OrdinalIgnoreCase))
{
var expr = new OrOperator()
{
Left = children[0],
Right = children[1]
}.Normalize();
for (var i = 2; i < children.Length; i++)
{
expr = new OrOperator()
{
Left = expr,
Right = children[i]
}.Normalize();
}
return(expr);
}
break;
case "not":
return(new NotOperator()
{
Arg = ProcessFilter(elem.Elements().First(), settings, prop)
}.Normalize());
case "condition":
return(ProcessFilter(elem.Elements().First(), settings, prop));
}
throw new InvalidOperationException();
}