#region Copyright & License Information
/*
 * Copyright 2007-2011 The OpenRA Developers (see AUTHORS)
 * This file is part of OpenRA, which is free software. It is made
 * available to you under the terms of the GNU General Public License
 * as published by the Free Software Foundation. For more information,
 * see COPYING.
 */
#endregion

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;

namespace OpenRA.Network
{
	class ReplayRecorderConnection : IConnection
	{
		IConnection inner;
		BinaryWriter writer;
		Func<string> chooseFilename;
		MemoryStream preStartBuffer = new MemoryStream();

		public ReplayRecorderConnection( IConnection inner, Func<string> chooseFilename )
		{
			this.chooseFilename = chooseFilename;
			this.inner = inner;

			writer = new BinaryWriter(preStartBuffer);
		}

		void StartSavingReplay(byte[] initialContent)
		{
			var filename = chooseFilename();
			var replaysDirectory = Path.Combine(Platform.SupportDir, "Replays");

			if (!Directory.Exists(replaysDirectory))
				Directory.CreateDirectory(replaysDirectory);

			FileStream file = null;
			var id = -1;
			while (file == null)
			{
				var fullFilename = Path.Combine(replaysDirectory, id < 0
					? "{0}.rep".F(filename)
					: "{0}-{1}.rep".F(filename, id));
				id++;
				try
				{
					file = File.Create(fullFilename);
				}
				catch (IOException) { }
			}

			file.Write(initialContent);
			this.writer = new BinaryWriter(file);
		}

		public int LocalClientId { get { return inner.LocalClientId; } }
		public ConnectionState ConnectionState { get { return inner.ConnectionState; } }

		public void Send( int frame, List<byte[]> orders ) { inner.Send( frame, orders ); }
		public void SendImmediate( List<byte[]> orders ) { inner.SendImmediate( orders ); }
		public void SendSync( int frame, byte[] syncData ) { inner.SendSync( frame, syncData ); }

		public void Receive( Action<int, byte[]> packetFn )
		{
			inner.Receive((client, data) =>
				{
					if (preStartBuffer != null && IsGameStart(data))
					{
						writer.Flush();
						var preStartData = preStartBuffer.ToArray();
						preStartBuffer = null;
						StartSavingReplay(preStartData);
					}

					writer.Write(client);
					writer.Write(data.Length);
					writer.Write(data);
					packetFn(client, data);
				} );
		}

		bool IsGameStart(byte[] data)
		{
			if (data.Length == 5 && data[4] == 0xbf)
				return false;
			if (data.Length >= 5 && data[4] == 0x65)
				return false;

			var frame = BitConverter.ToInt32(data, 0);
			return frame == 0 && data.ToOrderList(null).Any(
				o => o.OrderString == "StartGame");
		}

		bool disposed;

		public void Dispose()
		{
			if( disposed )
				return;

			writer.Close();
			inner.Dispose();
			disposed = true;
		}

		~ReplayRecorderConnection()
		{
			Dispose();
		}
	}
}