Implement Patcher and plugin providers

BepInEx.Preloader.Core/Patching/BasePatcherProvider.cs

@@ -0,0 +1,55 @@
+using System.Collections.Generic;
+using System.Reflection;
+using BepInEx.Configuration;
+using BepInEx.Logging;
+
+namespace BepInEx.Preloader.Core.Patching;
+
+/// <summary>
+///     A patcher provider that can discover and load assemblies containing patcher plugins
+/// </summary>
+public abstract class BasePatcherProvider
+{
+    protected BasePatcherProvider()
+    {
+        Info = PatcherPluginInfoAttribute.FromType(GetType());
+
+        Log = Logger.CreateLogSource(Info.Name);
+
+        Config = new ConfigFile(Utility.CombinePaths(Paths.ConfigPath, Info.GUID + ".cfg"), false,
+                                new BepInPlugin(Info.GUID, Info.Name, Info.Version.ToString()));
+    }
+
+    /// <summary>
+    ///     A <see cref="ILogSource" /> instance created for use by this patcher plugin provider.
+    /// </summary>
+    public ManualLogSource Log { get; }
+
+    /// <summary>
+    ///     A configuration file binding created with the <see cref="PatcherPluginInfoAttribute.GUID" /> of this provider as the
+    ///     filename.
+    /// </summary>
+    public ConfigFile Config { get; }
+
+    /// <summary>
+    ///     Metadata associated with this patcher plugin provider.
+    /// </summary>
+    public PatcherPluginInfoAttribute Info { get; }
+    
+    /// <summary>
+    ///     Obtains a list of assemblies containing patchers to load
+    /// </summary>
+    /// <returns>A list of loaders, one per assembly</returns>
+    public abstract IList<IPluginLoader> GetPatchers();
+
+    /// <summary>
+    ///     A custom assembly resolver that can be used by this provider to resolve assemblies
+    ///     that have failed to resolve
+    /// </summary>
+    /// <param name="name">The assembly's name</param>
+    /// <returns>The resolved assembly or null if the assembly couldn't be resolved</returns>
+    public virtual Assembly ResolveAssembly(string name)
+    {
+        return null;
+    }
+}