Reorder + analyzer cleanup

1 files changed, 120 insertions, 0 deletions

diff --git a/lib/Plugins.Runtime/src/LoaderExtensions.cs b/lib/Plugins.Runtime/src/LoaderExtensions.cs
new file mode 100644
index 0000000..795dcf5
--- /dev/null
+++ b/lib/Plugins.Runtime/src/LoaderExtensions.cs
@@ -0,0 +1,120 @@
+/*
+* Copyright (c) 2022 Vaughn Nugent
+* 
+* Library: VNLib
+* Package: VNLib.Plugins.Runtime
+* File: LoaderExtensions.cs 
+*
+* LoaderExtensions.cs is part of VNLib.Plugins.Runtime which is part of the larger 
+* VNLib collection of libraries and utilities.
+*
+* VNLib.Plugins.Runtime is free software: you can redistribute it and/or modify 
+* it under the terms of the GNU General Public License as published
+* by the Free Software Foundation, either version 2 of the License,
+* or (at your option) any later version.
+*
+* VNLib.Plugins.Runtime is distributed in the hope that it will be useful,
+* but WITHOUT ANY WARRANTY; without even the implied warranty of
+* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 
+* General Public License for more details.
+*
+* You should have received a copy of the GNU General Public License 
+* along with VNLib.Plugins.Runtime. If not, see http://www.gnu.org/licenses/.
+*/
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+
+namespace VNLib.Plugins.Runtime
+{
+    public static class LoaderExtensions
+    {
+        /// <summary>
+        /// Searches all plugins within the current loader for a 
+        /// single plugin that derrives the specified type
+        /// </summary>
+        /// <typeparam name="T">The type the plugin must derrive from</typeparam>
+        /// <param name="loader"></param>
+        /// <returns>The instance of the plugin that derrives from the specified type</returns>
+        public static LivePlugin? GetExposedPlugin<T>(this RuntimePluginLoader loader)
+        {
+            return loader.LivePlugins
+                .Where(static pl => typeof(T).IsAssignableFrom(pl.Plugin!.GetType()))
+                .SingleOrDefault();
+        }
+
+        /// <summary>
+        /// Searches all plugins within the current loader for a 
+        /// single plugin that derrives the specified type
+        /// </summary>
+        /// <typeparam name="T">The type the plugin must derrive from</typeparam>
+        /// <param name="loader"></param>
+        /// <returns>The instance of your custom type casted, or null if not found or could not be casted</returns>
+        public static T? GetExposedTypeFromPlugin<T>(this RuntimePluginLoader loader) where T: class
+        {
+            LivePlugin? plugin = loader.LivePlugins
+                .Where(static pl => typeof(T).IsAssignableFrom(pl.Plugin!.GetType()))
+                .SingleOrDefault();
+
+            return plugin?.Plugin as T;
+        }
+
+        /// <summary>
+        /// Registers a listener delegate method to invoke when the 
+        /// current <see cref="RuntimePluginLoader"/> is reloaded, and passes 
+        /// the new instance of the specified type
+        /// </summary>
+        /// <typeparam name="T">The single plugin type to register a listener for</typeparam>
+        /// <param name="loader"></param>
+        /// <param name="reloaded">The delegate method to invoke when the loader has reloaded plugins</param>
+        /// <exception cref="ArgumentNullException"></exception>
+        public static bool RegisterListenerForSingle<T>(this RuntimePluginLoader loader, Action<T, T> reloaded) where T: class
+        {
+            _ = reloaded ?? throw new ArgumentNullException(nameof(reloaded));
+
+            //try to get the casted type from the loader
+            T? current = loader.GetExposedTypeFromPlugin<T>();
+
+            if (current == null)
+            {
+                return false;
+            }
+            else
+            {
+                loader.Reloaded += delegate (object? sender, EventArgs args)
+                {
+                    RuntimePluginLoader wpl = (sender as RuntimePluginLoader)!;
+                    //Get the new loaded type
+                    T newT = (wpl.GetExposedPlugin<T>()!.Plugin as T)!;
+                    //Invoke reloaded action
+                    reloaded(current, newT);
+                    //update the new current instance
+                    current = newT;
+                };
+
+                return true;
+            }
+        }
+
+        /// <summary>
+        /// Gets all endpoints exposed by all exported plugin instances
+        /// within the current loader
+        /// </summary>
+        /// <param name="loader"></param>
+        /// <returns>An enumeration of all endpoints</returns>
+        public static IEnumerable<IEndpoint> GetEndpoints(this RuntimePluginLoader loader) => loader.LivePlugins.SelectMany(static pl => pl.Plugin!.GetEndpoints());
+
+        /// <summary>
+        /// Determines if any loaded plugin types exposes an instance of the 
+        /// specified type
+        /// </summary>
+        /// <typeparam name="T"></typeparam>
+        /// <param name="loader"></param>
+        /// <returns>True if any plugin instance exposes a the specified type, false otherwise</returns>
+        public static bool ExposesType<T>(this RuntimePluginLoader loader) where T : class
+        {
+            return loader.LivePlugins.Any(static pl => typeof(T).IsAssignableFrom(pl.Plugin?.GetType()));
+        }
+    }
+}