using CPF.Mac.Foundation;
using CPF.Mac.ObjCRuntime;
using System;
using System.Runtime.InteropServices;

namespace CPF.Mac.CoreGraphics
{
	public class CGDataConsumer : INativeObject, IDisposable
	{
		internal IntPtr handle;

		private IntPtr buffer;

		private byte[] reference;

		public IntPtr Handle => handle;

		public CGDataConsumer(IntPtr handle)
			: this(handle, owns: false)
		{
			this.handle = handle;
		}

		[Preserve(Conditional = true)]
		internal CGDataConsumer(IntPtr handle, bool owns)
		{
			this.handle = handle;
			if (!owns)
			{
				CGDataConsumerRetain(handle);
			}
		}

		~CGDataConsumer()
		{
			Dispose(disposing: false);
		}

		public void Dispose()
		{
			Dispose(disposing: true);
			GC.SuppressFinalize(this);
		}

		[DllImport("/System/Library/Frameworks/ApplicationServices.framework/Versions/A/Frameworks/CoreGraphics.framework/CoreGraphics")]
		private static extern void CGDataConsumerRelease(IntPtr handle);

		[DllImport("/System/Library/Frameworks/ApplicationServices.framework/Versions/A/Frameworks/CoreGraphics.framework/CoreGraphics")]
		private static extern void CGDataConsumerRetain(IntPtr handle);

		protected virtual void Dispose(bool disposing)
		{
			if (handle != IntPtr.Zero)
			{
				if (buffer != IntPtr.Zero)
				{
					Marshal.FreeHGlobal(buffer);
				}
				buffer = IntPtr.Zero;
				CGDataConsumerRelease(handle);
				handle = IntPtr.Zero;
			}
			reference = null;
		}

		[DllImport("/System/Library/Frameworks/ApplicationServices.framework/Versions/A/Frameworks/CoreGraphics.framework/CoreGraphics")]
		private static extern IntPtr CGDataConsumerCreateWithCFData(IntPtr data);

		public CGDataConsumer(NSMutableData data)
		{
			handle = CGDataConsumerCreateWithCFData(data.Handle);
		}
	}
}