using System;

using System.Reflection;

using System.Runtime.Serialization;

using System.Text;

using System.Xml.Serialization;

using ProtoBuf;



namespace Lokad.Serialization

{

	public static class ProtoBufUtil

	{

		public static string GetContractReference(Type type)

		{

			var attribs = type.GetCustomAttributes(false);

			var helper = new AttributeHelper(attribs);





			var name = Maybe.String

				.GetValue(() => helper.GetString<ProtoContractAttribute>(p => p.Name))

				.GetValue(() => helper.GetString<DataContractAttribute>(p => p.Name))

				.GetValue(() => helper.GetString<XmlTypeAttribute>(p => p.TypeName))

				.GetValue(() => type.Name);



			var ns = Maybe.String

				.GetValue(() => helper.GetString<DataContractAttribute>(p => p.Namespace))

				.GetValue(() => helper.GetString<XmlTypeAttribute>(p => p.Namespace))

				.Convert(s => s.Trim() + "/", "");



			return ns + name;

		}





		public static IFormatter CreateFormatter(Type type)

		{

			try

			{

				typeof(Serializer)

					.GetMethod("PrepareSerializer")

					.MakeGenericMethod(type)

					.Invoke(null, null);

			}

			catch (TargetInvocationException tie)

			{

				var message = string.Format("Failed to prepare ProtoBuf serializer for '{0}'.", type);

				throw new InvalidOperationException(message, tie.InnerException);

			}



			try

			{

				return (IFormatter)typeof(Serializer)

					.GetMethod("CreateFormatter")

					.MakeGenericMethod(type)

					.Invoke(null, null);

			}

			catch (TargetInvocationException tie)

			{

				var message = string.Format("Failed to create ProtoBuf formatter for '{0}'.", type);

				throw new InvalidOperationException(message, tie.InnerException);

			}

		}

	}

}