Improve EOR and add more TODO notes.

TelnetNegotiationCore/Interpretors/TelnetCharsetInterpretor.cs

@@ -224,6 +224,9 @@ private async Task CompleteCharsetAsync(StateMachine<State, Trigger>.Transition
 
 			CurrentEncoding = chosenEncoding;
 
+			// TODO: The implementing Server or Client needs to be warned when CurrentEncoding is set!
+			// This would allow, for instance, the Console to ensure it displays Unicode correctly.
+
 			await CallbackNegotiation(preamble.Concat(charsetAscii).Concat(postamble).ToArray());
 		}
 

TelnetNegotiationCore/Interpretors/TelnetEORInterpretor.cs

@@ -1,13 +1,12 @@
-using System;
-using System.Threading.Tasks;
+using System.Threading.Tasks;
 using Stateless;
 using TelnetNegotiationCore.Models;
 
 namespace TelnetNegotiationCore.Interpretors
 {
 	public partial class TelnetInterpretor
 	{
-		private bool _doEOR = false;
+		private bool? _doEOR = null;
 
 		/// <summary>
 		/// Character set Negotiation will set the Character Set and Character Page Server & Client have agreed to.
@@ -30,7 +29,7 @@ private StateMachine<State, Trigger> SetupEORNegotiation(StateMachine<State, Tri
 
 				tsm.Configure(State.DontEOR)
 					.SubstateOf(State.Accepting)
-					.OnEntry(() => _Logger.Debug("Connection: {connectionStatus}", "Client won't do EOR - do nothing"));
+					.OnEntryAsync(OnDontEORAsync);
 
 				RegisterInitialWilling(WillingEORAsync);
 			}
@@ -44,7 +43,7 @@ private StateMachine<State, Trigger> SetupEORNegotiation(StateMachine<State, Tri
 
 				tsm.Configure(State.WontEOR)
 					.SubstateOf(State.Accepting)
-					.OnEntry(() => _Logger.Debug("Connection: {connectionStatus}", "Server  won't do EOR - do nothing"));
+					.OnEntryAsync(WontEORAsync);
 
 				tsm.Configure(State.WillEOR)
 					.SubstateOf(State.Accepting)
@@ -54,6 +53,20 @@ private StateMachine<State, Trigger> SetupEORNegotiation(StateMachine<State, Tri
 			return tsm;
 		}
 
+		private async Task OnDontEORAsync()
+		{
+			_Logger.Debug("Connection: {connectionStatus}", "Client won't do EOR - do nothing");
+			_doEOR = false;
+			await Task.CompletedTask;
+		}
+
+		private async Task WontEORAsync()
+		{
+			_Logger.Debug("Connection: {connectionStatus}", "Server  won't do EOR - do nothing");
+			_doEOR = false;
+			await Task.CompletedTask;
+		}
+
 		/// <summary>
 		/// Announce we do EOR negotiation to the client.
 		/// </summary>
@@ -90,8 +103,11 @@ private async Task OnWillEORAsync(StateMachine<State, Trigger>.Transition _)
 		/// <returns>A completed Task</returns>
 		public async Task SendPromptAsync(byte[] send)
 		{
-			await CallbackNegotiation(send);
-			if (_doEOR)
+			if (_doEOR is null or false)
+			{
+				await CallbackNegotiation(send);
+			}
+			else
 			{
 				await CallbackNegotiation(new byte[] { (byte)Trigger.IAC, (byte)Trigger.EOR });
 			}