From 3906a7b34f9ecb1a4f8fdabcff8247a2750a8267 Mon Sep 17 00:00:00 2001
From: Stanley Dimant <stanley.dimant@varian.com>
Date: Mon, 30 Jan 2023 17:47:47 +0100
Subject: [PATCH] add start of mediator

---
 MareSynchronos/Mediator/IMessage.cs     |  3 ++
 MareSynchronos/Mediator/MareMediator.cs | 51 +++++++++++++++++++++++++
 MareSynchronos/Plugin.cs                |  6 +++
 3 files changed, 60 insertions(+)
 create mode 100644 MareSynchronos/Mediator/IMessage.cs
 create mode 100644 MareSynchronos/Mediator/MareMediator.cs

diff --git a/MareSynchronos/Mediator/IMessage.cs b/MareSynchronos/Mediator/IMessage.cs
new file mode 100644
index 0000000..68e4d6c
--- /dev/null
+++ b/MareSynchronos/Mediator/IMessage.cs
@@ -0,0 +1,3 @@
+namespace MareSynchronos.Mediator;
+
+public interface IMessage { }
\ No newline at end of file
diff --git a/MareSynchronos/Mediator/MareMediator.cs b/MareSynchronos/Mediator/MareMediator.cs
new file mode 100644
index 0000000..03ee16d
--- /dev/null
+++ b/MareSynchronos/Mediator/MareMediator.cs
@@ -0,0 +1,51 @@
+using MareSynchronos.Utils;
+
+namespace MareSynchronos.Mediator;
+
+public class MareMediator : IDisposable
+{
+    private record MediatorSubscriber(object Subscriber, Action<IMessage> Action);
+
+    private readonly Dictionary<Type, HashSet<MediatorSubscriber>> _subscriberDict = new();
+
+    public void Subscribe<T>(object subscriber, Action<IMessage> action) where T : IMessage
+    {
+        _subscriberDict.TryAdd(typeof(T), new HashSet<MediatorSubscriber>());
+
+        if (!_subscriberDict[typeof(T)].Add(new(subscriber, action)))
+        {
+            throw new InvalidOperationException("Already subscribed");
+        }
+    }
+
+    public void Unsubscribe<T>(object subscriber) where T : IMessage
+    {
+        if (_subscriberDict.TryGetValue(typeof(T), out var subscribers))
+        {
+            subscribers.RemoveWhere(p => p.Subscriber == subscriber);
+        }
+    }
+
+    public void Publish(IMessage message)
+    {
+        if (_subscriberDict.TryGetValue(message.GetType(), out var subscribers))
+        {
+            foreach (var subscriber in subscribers)
+            {
+                try
+                {
+                    subscriber.Action.Invoke(message);
+                }
+                catch (Exception ex)
+                {
+                    Logger.Error("Error executing " + subscriber.Action.Method, ex);
+                }
+            }
+        }
+    }
+
+    public void Dispose()
+    {
+        _subscriberDict.Clear();
+    }
+}
\ No newline at end of file
diff --git a/MareSynchronos/Plugin.cs b/MareSynchronos/Plugin.cs
index 7b8a4bb..e9fc7e5 100644
--- a/MareSynchronos/Plugin.cs
+++ b/MareSynchronos/Plugin.cs
@@ -16,6 +16,7 @@ using Dalamud.Game.Gui;
 using MareSynchronos.Export;
 using Dalamud.Data;
 using MareSynchronos.MareConfiguration;
+using MareSynchronos.Mediator;
 
 namespace MareSynchronos;
 
@@ -46,6 +47,7 @@ public sealed class Plugin : IDalamudPlugin
     private readonly ServerConfigurationManager _serverConfigurationManager;
     private readonly GposeUi _gposeUi;
     private readonly ConfigurationService _configurationService;
+    private readonly MareMediator _mediator;
 
 
     public Plugin(DalamudPluginInterface pluginInterface, CommandManager commandManager, DataManager gameData,
@@ -56,6 +58,7 @@ public sealed class Plugin : IDalamudPlugin
         _pluginInterface.UiBuilder.DisableGposeUiHide = true;
         _commandManager = commandManager;
         _configurationService = new(_pluginInterface);
+        _mediator = new();
 
         _localization = new Dalamud.Localization("MareSynchronos.Localization.", "", useEmbedded: true);
         _localization.SetupWithLangCode("en");
@@ -138,6 +141,9 @@ public sealed class Plugin : IDalamudPlugin
         _transientResourceManager?.Dispose();
         _dalamudUtil.Dispose();
         _configurationService?.Dispose();
+
+        _mediator.Dispose();
+
         Logger.Debug("Shut down");
     }