Load third-party libraries before loading plugins

BrackeysBot/BrackeysBotApp.cs

@@ -1,4 +1,7 @@
-using System.Reflection;
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Reflection;
 using System.Threading;
 using System.Threading.Tasks;
 using BrackeysBot.API;
@@ -14,6 +17,8 @@ namespace BrackeysBot;
 /// </summary>
 internal sealed class BrackeysBotApp : BackgroundService, IBot
 {
+    private readonly List<Assembly> _libraries = new();
+
     /// <summary>
     ///     Initializes a new instance of the <see cref="BrackeysBotApp" /> class.
     /// </summary>
@@ -23,6 +28,12 @@ public BrackeysBotApp()
         Version = assembly.GetName().Version!.ToString(3);
     }
 
+    /// <summary>
+    ///     Gets the <c>libraries</c> directory for this bot.
+    /// </summary>
+    /// <value>The <c>libraries</c> directory.</value>
+    public DirectoryInfo LibrariesDirectory { get; } = new("libraries");
+
     /// <inheritdoc />
     public ILogger Logger { get; } = LogManager.GetLogger("BrackeysBot");
 
@@ -50,17 +61,52 @@ public void EnablePlugins()
             PluginManager.EnablePlugin(plugin);
     }
 
+    /// <summary>
+    ///     Loads third party dependencies as found <see cref="LibrariesDirectory" />.
+    /// </summary>
+    public void LoadLibraries()
+    {
+        foreach (FileInfo file in LibrariesDirectory.EnumerateFiles("*.dll"))
+        {
+            try
+            {
+                Assembly assembly = Assembly.LoadFrom(file.FullName);
+                if (!_libraries.Contains(assembly))
+                    _libraries.Add(assembly);
+                Logger.Debug($"Loaded {assembly.GetName()}");
+            }
+            catch (Exception exception)
+            {
+                Logger.Warn(exception, $"Could not load library '{file.Name}' - SOME PLUGINS MAY NOT WORK");
+            }
+        }
+    }
+
     /// <inheritdoc />
     protected override Task ExecuteAsync(CancellationToken stoppingToken)
     {
         Logger.Info($"Starting Brackeys Bot version {Version}");
 
+        LoadLibraries();
+        int libraryCount = _libraries.Count;
+        Logger.Info($"Loaded {libraryCount} {(libraryCount == 1 ? "library" : "libraries")}");
+
         PluginManager.LoadPlugins();
-        Logger.Info($"Loaded {PluginManager.LoadedPlugins.Count} plugins");
+        int loadedPluginCount = PluginManager.LoadedPlugins.Count;
+        Logger.Info($"Loaded {loadedPluginCount} {(loadedPluginCount == 1 ? "plugin" : "plugins")}");
 
         EnablePlugins();
-        Logger.Info($"Enabled {PluginManager.EnabledPlugins.Count} plugins");
+        int enabledPluginCount = PluginManager.EnabledPlugins.Count;
+        Logger.Info($"Enabled {enabledPluginCount} {(enabledPluginCount == 1 ? "plugin" : "plugins")}");
 
         return Task.CompletedTask;
     }
+
+    public override Task StopAsync(CancellationToken cancellationToken)
+    {
+        DisablePlugins();
+        foreach (Plugin plugin in PluginManager.LoadedPlugins) PluginManager.UnloadPlugin(plugin);
+
+        return base.StopAsync(cancellationToken);
+    }
 }