using System;
using System.Runtime.InteropServices;

namespace CPF.Mac.ObjCRuntime
{
	[AttributeUsage(AttributeTargets.Class, AllowMultiple = true)]
	public class AdoptsAttribute : Attribute
	{
		private IntPtr handle;

		public string ProtocolType
		{
			get;
			private set;
		}

		public IntPtr ProtocolHandle
		{
			get
			{
				if (handle == IntPtr.Zero && ProtocolType != null)
				{
					handle = objc_getProtocol(ProtocolType);
				}
				return handle;
			}
		}

		[DllImport("/usr/lib/libobjc.dylib")]
		internal static extern IntPtr objc_getProtocol(string proto);

		public AdoptsAttribute(string protocolType)
		{
			ProtocolType = protocolType;
		}
	}
}