Implement machine linking (#1784)

* Implement machine linking

* Cleanup and rename Signals

* Implement signal button

* Add machine linking signal mapping

* Fix signallink command help

* Add localization to signal linking and allow infinite range

* Add feedback for when a transmitter is not connected to any receivers

Refactor PopupMessage to use the entity extension
Refactor dependencies to not have to disable warnings

Content.Server/GameObjects/EntitySystems/SignalLinkerSystem.cs

@@ -0,0 +1,140 @@
+using Content.Server.GameObjects.Components.MachineLinking;
+using Robust.Server.Interfaces.Console;
+using Robust.Server.Interfaces.Player;
+using Robust.Shared.GameObjects;
+using Robust.Shared.GameObjects.Systems;
+using Robust.Shared.Input;
+using Robust.Shared.Input.Binding;
+using Robust.Shared.Interfaces.GameObjects;
+using Robust.Shared.IoC;
+using Robust.Shared.Map;
+using Robust.Shared.Network;
+using Robust.Shared.Players;
+using System.Collections.Generic;
+
+namespace Content.Server.GameObjects.EntitySystems
+{
+    public class SignalLinkerSystem : EntitySystem
+    {
+        private Dictionary<NetSessionId, SignalTransmitterComponent> _transmitters;
+
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            _transmitters = new Dictionary<NetSessionId, SignalTransmitterComponent>();
+        }
+
+        public void SignalLinkerKeybind(NetSessionId id, bool? enable)
+        {
+            if (enable == null)
+            {
+                enable = !_transmitters.ContainsKey(id);
+            }
+
+            if (enable == true)
+            {
+                if (_transmitters.ContainsKey(id))
+                {
+                    return;
+                }
+
+                if (_transmitters.Count == 0)
+                {
+                    CommandBinds.Builder
+                        .Bind(EngineKeyFunctions.Use, new PointerInputCmdHandler(HandleUse))
+                        .Register<SignalLinkerSystem>();
+                }
+
+                _transmitters.Add(id, null);
+
+            }
+            else if (enable == false)
+            {
+                if (!_transmitters.ContainsKey(id))
+                {
+                    return;
+                }
+
+                _transmitters.Remove(id);
+                if (_transmitters.Count == 0)
+                {
+                    CommandBinds.Unregister<SignalLinkerSystem>();
+                }
+            }
+        }
+
+        private bool HandleUse(ICommonSession session, GridCoordinates coords, EntityUid uid)
+        {
+            if (!_transmitters.TryGetValue(session.SessionId, out var signalTransmitter))
+            {
+                return false;
+            }
+
+            if (!EntityManager.TryGetEntity(uid, out var entity))
+            {
+                return false;
+            }
+
+            if (entity == null)
+            {
+                return false;
+            }
+
+            if (entity.TryGetComponent<SignalReceiverComponent>(out var signalReceiver))
+            {
+                if (signalReceiver.Interact(session.AttachedEntity, signalTransmitter))
+                {
+                    return true;
+                }
+            }
+
+            if (entity.TryGetComponent<SignalTransmitterComponent>(out var transmitter))
+            {
+                _transmitters[session.SessionId] = transmitter.GetSignal(session.AttachedEntity);
+
+                return true;
+            }
+
+            return false;
+        }
+
+    }
+
+    public class SignalLinkerCommand : IClientCommand
+    {
+        public string Command => "signallink";
+
+        public string Description => "Turns on signal linker mode. Click a transmitter to tune that signal and then click on each receiver to tune them to the transmitter signal.";
+
+        public string Help => "signallink (on/off)";
+
+        public void Execute(IConsoleShell shell, IPlayerSession player, string[] args)
+        {
+            bool? enable = null;
+            if (args.Length > 0)
+            {
+                if (args[0] == "on")
+                    enable = true;
+                else if (args[0] == "off")
+                    enable = false;
+                else if (bool.TryParse(args[0], out var boolean))
+                    enable = boolean;
+                else if (int.TryParse(args[0], out var num))
+                {
+                    if (num == 1)
+                        enable = true;
+                    else if (num == 0)
+                        enable = false;
+                }
+            }
+
+            if (!IoCManager.Resolve<IEntitySystemManager>().TryGetEntitySystem<SignalLinkerSystem>(out var system))
+            {
+                return;
+            }
+
+            system.SignalLinkerKeybind(player.SessionId, enable);
+        }
+    }
+}