/// <summary>
/// Inspects the provided type and generates a type expression to represent it in the object grpah.
/// </summary>
/// <param name="typeToCheck">The complete type specification to check.</param>
/// <param name="typeDefinition">An optional expression declaration to use as a set of overrides on the type provided.</param>
/// <returns>GraphFieldOptions.</returns>
public static GraphTypeExpression GenerateTypeExpression(Type typeToCheck, IGraphTypeExpressionDeclaration typeDefinition = null)
{
Validation.ThrowIfNull(typeToCheck, nameof(typeToCheck));
if (typeDefinition?.TypeWrappers != null)
{
typeToCheck = GraphValidation.EliminateWrappersFromCoreType(
typeToCheck,
eliminateEnumerables: true,
eliminateTask: true,
eliminateNullableT: true);
return(new GraphTypeExpression(typeToCheck.FriendlyName(), typeDefinition.TypeWrappers));
}
// strip out Task{T} before doin any type inspections
typeToCheck = GraphValidation.EliminateWrappersFromCoreType(
typeToCheck,
eliminateEnumerables: false,
eliminateTask: true,
eliminateNullableT: false);
var hasDefinedDefaultValue = typeDefinition?.HasDefaultValue ?? false;
List <MetaGraphTypes> wrappers = new List <MetaGraphTypes>();
if (GraphValidation.IsValidListType(typeToCheck))
{
// auto generated type expressions will always allow for a nullable list (since class references can be null)
// unwrap any nested lists as necessary: e.g. IEnumerable<IEnumerable<IEnumerable<T>>>
while (true)
{
var unwrappedType = EliminateNextWrapperFromCoreType(
typeToCheck,
eliminateEnumerables: true,
eliminateTask: false,
eliminateNullableT: false);
if (unwrappedType == typeToCheck)
{
break;
}
wrappers.Add(MetaGraphTypes.IsList);
typeToCheck = unwrappedType;
}
if (!hasDefinedDefaultValue && GraphValidation.IsNotNullable(typeToCheck))
{
wrappers.Add(MetaGraphTypes.IsNotNull);
}
}
else if (!hasDefinedDefaultValue && GraphValidation.IsNotNullable(typeToCheck))
{
wrappers.Add(MetaGraphTypes.IsNotNull);
}
typeToCheck = EliminateWrappersFromCoreType(
typeToCheck,
eliminateEnumerables: false,
eliminateTask: false,
eliminateNullableT: true);
return(new GraphTypeExpression(typeToCheck.FriendlyName(), wrappers));
}
