using System;

namespace Python.Runtime.Codecs
{
 [Obsolete]
 public sealed class EnumPyIntCodec : IPyObjectEncoder, IPyObjectDecoder
 {
 public static EnumPyIntCodec Instance { get; } = new EnumPyIntCodec();

 public bool CanDecode(PyType objectType, Type targetType)
 {
 return targetType.IsEnum
 && objectType.IsSubclass(Runtime.PyLongType);
 }

 public bool CanEncode(Type type)
 {
 return type == typeof(object) || type == typeof(ValueType) || type.IsEnum;
 }

 public bool TryDecode<T>(PyObject pyObj, out T? value)
 {
 value = default;
 if (!typeof(T).IsEnum) return false;

 Type etype = Enum.GetUnderlyingType(typeof(T));

 if (!PyInt.IsIntType(pyObj)) return false;

 object? result;
 try
 {
 result = pyObj.AsManagedObject(etype);
 }
 catch (InvalidCastException)
 {
 return false;
 }

 if (Enum.IsDefined(typeof(T), result) || typeof(T).IsFlagsEnum())
 {
 value = (T)Enum.ToObject(typeof(T), result);
 return true;
 }

 return false;
 }

 public PyObject? TryEncode(object value)
 {
 if (value is null) return null;

 var enumType = value.GetType();
 if (!enumType.IsEnum) return null;

 try
 {
 return new PyInt(Convert.ToInt64(value));
 }
 catch (OverflowException)
 {
 return new PyInt(Convert.ToUInt64(value));
 }
 }

 private EnumPyIntCodec() { }
 }
}