add bootstrap and plugins prototype

CringePlugins/Utils/IntrospectionContext.cs

@@ -0,0 +1,49 @@
+using System.Reflection;
+using dnlib.DotNet;
+
+namespace CringePlugins.Utils;
+
+public class IntrospectionContext
+{
+    public static IntrospectionContext Global { get; } = new();
+    
+    private readonly ModuleContext _context = ModuleDef.CreateModuleContext();
+
+    public IEnumerable<Type> CollectAttributedTypes<TAttribute>(Module module, bool allowAbstract = false) where TAttribute : Attribute
+    {
+        var moduleDef = ModuleDefMD.Load(module, _context);
+
+        return moduleDef.GetTypes()
+            .Where(b => b.CustomAttributes.IsDefined(typeof(TAttribute).FullName) && (allowAbstract || !b.IsAbstract))
+            .Select(b => module.GetType(b.FullName, true, false)!);
+    }
+
+    public IEnumerable<Type> CollectDerivedTypes<T>(Module module, bool allowAbstract = false)
+    {
+        var moduleDef = ModuleDefMD.Load(module, _context);
+
+        var token =  moduleDef.ImportAsTypeSig(typeof(T));
+
+        return moduleDef.GetTypes()
+            .Where(b => (typeof(T).IsInterface
+                ? b.Interfaces.Any(i => i.Interface.FullName == token.FullName)
+                : MatchBaseType(b, token)) && (allowAbstract || !b.IsAbstract))
+            .Select(b => module.GetType(b.FullName, true, false)!);
+    }
+
+    private static bool MatchBaseType(ITypeDefOrRef? defOrRef, TypeSig token)
+    {
+        while ((defOrRef = defOrRef.GetBaseType()) != null)
+        {
+            if (defOrRef.FullName == token.FullName)
+                return true;
+        }
+        
+        return false;
+    }
+}
+
+public static class AssemblyExtensions
+{
+    public static Module GetMainModule(this Assembly assembly) => assembly.GetModule(assembly.GetName().Name! + ".dll") ?? assembly.GetModules()[0];
+}