private static string ComputeArray(Expression array, ArrayPostfixMode arrayPostfixMode, RequestBuilderConfiguration configuration)
{
var list = string.Join(
",",
(array as NewArrayExpression).Expressions.Select(e => Run(e as ConstantExpression, configuration))
);
return(arrayPostfixMode switch
{
ArrayPostfixMode.ContainsAny => $"({list})",
ArrayPostfixMode.ContainsAll => $"[{list}]",
ArrayPostfixMode.ExactMatch => $"{{{list}}}",
_ => throw new Exception("Unknown array postfix mode"),
});
/// <summary>
/// Interpretes a predicate to convert it to a string usable by IGDB API
/// </summary>
/// <param name="predicate"></param>
/// <returns></returns>
public static string Run(Expression predicate, RequestBuilderConfiguration configuration, bool invert = false, ArrayPostfixMode arrayPostfixMode = ArrayPostfixMode.ContainsAny)
{
if (predicate is null)
{
throw new ArgumentNullException(nameof(predicate));
}
var binaryPredicate = predicate as BinaryExpression;
switch (predicate.NodeType)
{
/*
* First part of switch : binary operators
* -------
* if Node type referes to a binary operators we set the operator
* and let the method continue after the switch to create the
* expression.
* binary operators are either logical operators (&& or ||),
* relational operators (>, >=, <, <=) or equality operators (==, !=)
*/
case ExpressionType.AndAlso:
return(ComputeBinaryOperator(binaryPredicate.Left, binaryPredicate.Right, "&", configuration));
case ExpressionType.OrElse:
return(ComputeBinaryOperator(binaryPredicate.Left, binaryPredicate.Right, "|", configuration));
case ExpressionType.GreaterThan:
return(ComputeBinaryOperator(binaryPredicate.Left, binaryPredicate.Right, ">", configuration));
case ExpressionType.GreaterThanOrEqual:
return(ComputeBinaryOperator(binaryPredicate.Left, binaryPredicate.Right, ">=", configuration));
case ExpressionType.LessThan:
return(ComputeBinaryOperator(binaryPredicate.Left, binaryPredicate.Right, "<", configuration));
case ExpressionType.LessThanOrEqual:
return(ComputeBinaryOperator(binaryPredicate.Left, binaryPredicate.Right, "<=", configuration));
case ExpressionType.NotEqual:
return(ComputeBinaryOperator(binaryPredicate.Left, binaryPredicate.Right, "!=", configuration));
case ExpressionType.Equal:
return(ComputeBinaryOperator(binaryPredicate.Left, binaryPredicate.Right, "=", configuration));
/*
* Second part of switch : members
* -------
* If node type refers to a member, a constant or an array then
* then return an interpretation.
*/
case ExpressionType.MemberAccess:
return(ComputeMemberAccess(predicate, configuration));
case ExpressionType.Constant:
return(ComputeConstant(predicate, configuration));
case ExpressionType.NewArrayInit:
return(ComputeArray(predicate, arrayPostfixMode, configuration));
/*
* Third part of switch : methods
* -------
* if node type referes to a method corresponding to
*/
case ExpressionType.Not:
return(ComputeNotCall(predicate, configuration));
case ExpressionType.Call:
return(ComputeMethodCall(predicate, configuration, invert));
default:
throw new InvalidPredicateException(predicate);
}
}
