private static Expression GetThenByCall(this Expression expression, OrderByClause orderByClause)
{
const string ThenBy = "ThenBy";
const string ThenByDescending = "ThenByDescending";
return(orderByClause.ThenBy == null
? GetMethodCall()
: GetMethodCall().GetThenByCall(orderByClause.ThenBy));
Expression GetMethodCall()
{
return(orderByClause.Expression switch
{
CountNode countNode => expression.GetOrderByCountCall
(
countNode.GetPropertyPath(),
orderByClause.Direction == OrderByDirection.Ascending
? ThenBy
: ThenByDescending
),
SingleValuePropertyAccessNode propertyNode => expression.GetOrderByCall
(
propertyNode.GetPropertyPath(),
orderByClause.Direction == OrderByDirection.Ascending
? ThenBy
: ThenByDescending
),
_ => throw new ArgumentException($"Unsupported SingleValueNode value: {orderByClause.Expression.GetType()}"),
});
}
private static Expression GetOrderByCall(this Expression expression, OrderByClause orderByClause)
{
const string OrderBy = "OrderBy";
const string OrderByDescending = "OrderByDescending";
return(orderByClause.ThenBy == null
? GetMethodCall()
: GetMethodCall().GetThenByCall(orderByClause.ThenBy));
Expression GetMethodCall()
{
SingleValueNode orderByNode = orderByClause.Expression;
switch (orderByNode)
{
case CountNode countNode:
return(expression.GetOrderByCountCall
(
countNode.GetPropertyPath(),
orderByClause.Direction == OrderByDirection.Ascending
? OrderBy
: OrderByDescending,
orderByClause.RangeVariable.Name
));
default:
SingleValuePropertyAccessNode propertyNode = (SingleValuePropertyAccessNode)orderByNode;
return(expression.GetOrderByCall
(
propertyNode.GetPropertyPath(),
orderByClause.Direction == OrderByDirection.Ascending
? OrderBy
: OrderByDescending,
orderByClause.RangeVariable.Name
));
}
}
}
