private static object Create(Cat cat, Type type, Type[] genericArguments)
{
if (genericArguments.Length > 0)
{
type = type.MakeGenericType(genericArguments);
}
var constructors = type.GetConstructors();
if (constructors.Length == 0)
{
throw new InvalidOperationException($"Cannot create the instance of {type} which does not have an public constructor.");
}
var constructor = constructors.FirstOrDefault(it => it.GetCustomAttributes(false).OfType <InjectionAttribute>().Any());
constructor = constructor ?? constructors.First();
var parameters = constructor.GetParameters();
if (parameters.Length == 0)
{
return(Activator.CreateInstance(type));
}
var arguments = new object[parameters.Length];
for (int index = 0; index < arguments.Length; index++)
{
var parameter = parameters[index];
var parameterType = parameter.ParameterType;
if (cat.HasRegistry(parameterType))
{
arguments[index] = cat.GetService(parameterType);
}
else if (parameter.HasDefaultValue)
{
arguments[index] = parameter.DefaultValue;
}
else
{
throw new InvalidOperationException($"Cannot create the instance of {type} whose constructor has non-registered parameter type(s)");
}
}
return(Activator.CreateInstance(type, arguments));
}
public static bool HasRegistry <T>(this Cat cat) => cat.HasRegistry(typeof(T));