using System.Collections.Generic;
using System.IO;
using System;
using System.Threading;
using System.IO.Pipes;
using SlimDX;
using SlimDX.DirectInput;

//this is not a very safe or pretty protocol, I'm not proud of it

namespace BizHawk.Client.EmuHawk
{
	public static class IPCKeyInput
	{
		public static void Initialize()
		{
			var t = new Thread(IPCThread);
			t.IsBackground = true;
			t.Start();
		}


		static List<KeyInput.KeyEvent> PendingEventList = new List<KeyInput.KeyEvent>();
		static List<KeyInput.KeyEvent> EventList = new List<KeyInput.KeyEvent>();

		static void IPCThread()
		{
			string pipeName = $"bizhawk-pid-{System.Diagnostics.Process.GetCurrentProcess().Id}-IPCKeyInput";


			for (; ; )
			{
				using (NamedPipeServerStream pipe = new NamedPipeServerStream(pipeName, PipeDirection.In, 1, PipeTransmissionMode.Byte, PipeOptions.Asynchronous, 1024, 1024))
				{
					try
					{
						pipe.WaitForConnection();

						BinaryReader br = new BinaryReader(pipe);

						for (; ; )
						{
							int e = br.ReadInt32();
							bool pressed = (e & 0x80000000) != 0;
							lock (PendingEventList)
								PendingEventList.Add(new KeyInput.KeyEvent { Key = (Key)(e & 0x7FFFFFFF), Pressed = pressed });
						}
					}
					catch { }
				}
			}
		}

		public static IEnumerable<KeyInput.KeyEvent> Update()
		{
			EventList.Clear();

			lock (PendingEventList)
			{
				EventList.AddRange(PendingEventList);
				PendingEventList.Clear();
			}

			return EventList;
		}
	}
}