using System;
using System.Text;
using System.IO;
using System.Runtime.InteropServices;

//todo - quit using Console.WriteLine (well, we can leave it hooked up as a backstop)
//use a different method instead, so we can collect unicode data
//also, collect log data independently of whether the log window is open
//we also need to dice it into lines so that we can have a backlog policy

namespace BizHawk.MultiClient
{
    static class LogConsole
    {
        public static bool ConsoleVisible 
        { 
            get; 
            private set; 
        }

		static LogWindow window;
		static LogStream logStream;
		static StringBuilder sbLog;

		class LogStream : Stream
		{
			public LogStream()
			{
			}

			public override bool CanRead { get { return false; } }
			public override bool CanSeek { get { return false; } }
			public override bool CanWrite { get { return true; } }

			public override void Flush()
			{
				//TODO - maybe this will help with decoding
			}

			public override long Length
			{
				get { throw new NotImplementedException(); }
			}

			public override long Position
			{
				get
				{
					throw new NotImplementedException();
				}
				set
				{
					throw new NotImplementedException();
				}
			}

			public override int Read(byte[] buffer, int offset, int count)
			{
				throw new NotImplementedException();
			}

			public override long Seek(long offset, SeekOrigin origin)
			{
				throw new NotImplementedException();
			}

			public override void SetLength(long value)
			{
				throw new NotImplementedException();
			}

			public override void Write(byte[] buffer, int offset, int count)
			{
				//TODO - buffer undecoded characters (this may be important)
				//(use decoder = System.Text.Encoding.Unicode.GetDecoder())
				string str = System.Text.Encoding.ASCII.GetString(buffer, offset, count);
				if (Emit != null)
					Emit(str);
			}

			public Action<string> Emit;
		}

        public static void ShowConsole()
        {
            if (ConsoleVisible) return;
			ConsoleVisible = true;

			logStream = new LogStream();
			var sout = new StreamWriter(logStream) { AutoFlush = true };
			Console.SetOut(sout);
			window = new LogWindow();
			window.Show();
			sbLog = new StringBuilder(); //not using this right now
			logStream.Emit = (str) => { window.Append(str); };
        }

        public static void HideConsole()
        {
            if (ConsoleVisible == false) return;
			window.Dispose();
			logStream.Dispose();
			logStream = null;
			window = null;
			
			Console.SetOut(TextWriter.Null);
			ConsoleVisible = false;
        }
    }
}