Support for Reflection Lookup of Mod Types (#117)

* Modified reflection utils to support lookup across multiple assemblies.
* Added registration of generated mod assembly to LuaCs Compiler.

Barotrauma/BarotraumaShared/SharedSource/LuaCs/Cs/CsScriptLoader.cs

@@ -87,7 +87,6 @@ namespace Barotrauma
             foreach (var cp in ContentPackageManager.AllPackages.Concat(ContentPackageManager.EnabledPackages.All))
             {
                 if (packagesAdded.Contains(cp)) { continue; }
-
                 var path = $"{Path.GetFullPath(Path.GetDirectoryName(cp.Path)).Replace('\\', '/')}/";
                 if (ShouldRun(cp, path))
                 {
@@ -102,7 +101,6 @@ namespace Barotrauma
                     {
                         paths.Add(cp.Name, path);
                     }
-
                     packagesAdded.Add(cp);
                 }
             }
@@ -169,14 +167,14 @@ namespace Barotrauma
             return syntaxTrees;
         }
 
-        public List<Type> Compile()
+        public List<Type> Compile() 
         {
             IEnumerable<SyntaxTree> syntaxTrees = ParseSources();
 
             var options = new CSharpCompilationOptions(OutputKind.DynamicallyLinkedLibrary)
                 .WithMetadataImportOptions(MetadataImportOptions.All)
                 .WithOptimizationLevel(OptimizationLevel.Release)
-                .WithAllowUnsafe(false);
+                .WithAllowUnsafe(true); 
             var compilation = CSharpCompilation.Create(CsScriptAssembly, syntaxTrees, defaultReferences, options);
 
             using (var mem = new MemoryStream())
@@ -188,7 +186,9 @@ namespace Barotrauma
 
                     string errStr = "CS MODS NOT LOADED | Compilation errors:";
                     foreach (Diagnostic diagnostic in failures)
+                    {
                         errStr += $"\n{diagnostic}";
+                    }
                     LuaCsSetup.PrintCsError(errStr);
                 }
                 else
@@ -200,7 +200,16 @@ namespace Barotrauma
 
             if (Assembly != null)
             {
-                return Assembly.GetTypes().Where(t => t.IsSubclassOf(typeof(ACsMod))).ToList();
+                RegisterAssemblyWithNativeGame(Assembly);
+                try
+                {
+                    return Assembly.GetTypes().Where(t => t.IsSubclassOf(typeof(ACsMod))).ToList();
+                }
+                catch (ReflectionTypeLoadException re)
+                {
+                    LuaCsSetup.PrintCsError($"Unable to load CsMod Types. {re.Message}");
+                    throw re;
+                }
             }
             else
             {
@@ -208,6 +217,23 @@ namespace Barotrauma
             }
         }
 
+        /// <summary>
+        /// This function should be used whenever a new assembly is created. Wrapper to allow more complicated setup later if need be.
+        /// </summary>
+        private static void RegisterAssemblyWithNativeGame(Assembly assembly)
+        {
+            Barotrauma.ReflectionUtils.AddNonAbstractAssemblyTypes(assembly);
+        }
+
+        /// <summary>
+        /// This function should be used whenever a new assembly is about to be destroyed/unloaded. Wrapper to allow more complicated setup later if need be.
+        /// </summary>
+        /// <param name="assembly">Assembly to remove</param>
+        private static void UnregisterAssemblyFromNativeGame(Assembly assembly)
+        {
+            Barotrauma.ReflectionUtils.RemoveAssemblyFromCache(assembly);
+        }
+
         private static string[] DirSearch(string sDir)
         {
             if (!Directory.Exists(sDir))
@@ -220,7 +246,11 @@ namespace Barotrauma
 
         public void Clear()
         {
-            Assembly = null;
+            if (Assembly != null)
+            {
+                UnregisterAssemblyFromNativeGame(Assembly);
+                Assembly = null;
+            }
         }
     }
 }

Barotrauma/BarotraumaShared/SharedSource/Utils/ReflectionUtils.cs

@@ -12,17 +12,61 @@ namespace Barotrauma
         private static readonly Dictionary<Assembly, ImmutableArray<Type>> cachedNonAbstractTypes
             = new Dictionary<Assembly, ImmutableArray<Type>>();
 
+        
         public static IEnumerable<Type> GetDerivedNonAbstract<T>()
         {
             Assembly assembly = typeof(T).Assembly;
             if (!cachedNonAbstractTypes.ContainsKey(assembly))
             {
-                cachedNonAbstractTypes[assembly] = assembly.GetTypes()
-                    .Where(t => !t.IsAbstract).ToImmutableArray();
+                AddNonAbstractAssemblyTypes(assembly);
             }
-            return cachedNonAbstractTypes[assembly].Where(t => t.IsSubclassOf(typeof(T)));
+
+            #warning TODO: Add safety checks in case an assembly is unloaded without being removed from the cache.
+            
+            List<Type> types = new List<Type>();
+            foreach (var typearr in cachedNonAbstractTypes)
+            {
+                types = types.Concat(typearr.Value.Where(t => t.IsSubclassOf(typeof(T)))).ToList();
+            }
+            
+            return types;
         }
 
+        /// <summary>
+        /// Adds an assembly's Non-Abstract Types to the cache for Barotrauma's Type lookup. 
+        /// </summary>
+        /// <param name="assembly">Assembly to be added</param>
+        /// <param name="overwrite">Whether or not to overwrite an entry if the assembly already exists within it.</param>
+        public static void AddNonAbstractAssemblyTypes(Assembly assembly, bool overwrite = false)
+        {
+            if (cachedNonAbstractTypes.ContainsKey(assembly))
+            {
+                if (!overwrite)
+                {
+                    DebugConsole.LogError(
+                        $"ReflectionUtils::AddNonAbstractAssemblyTypes() | The assembly [{assembly.GetName()}] already exists in the cache.");
+                    return;
+                }
+                cachedNonAbstractTypes.Remove(assembly);
+            }
+
+            try
+            {
+                if (!cachedNonAbstractTypes.TryAdd(assembly, assembly.GetTypes().Where(t => !t.IsAbstract).ToImmutableArray()))
+                    DebugConsole.LogError($"ReflectionUtils::AddNonAbstractAssemblyTypes() | Unable to add types from Assembly to cache.");
+            }
+            catch (ReflectionTypeLoadException e)
+            {
+                DebugConsole.LogError($"ReflectionUtils::AddNonAbstractAssemblyTypes() | RTFException: Unable to load Assembly Types from {assembly.GetName()}.");
+            }
+        }
+
+        /// <summary>
+        /// Removes an assembly from the cache for Barotrauma's Type lookup.
+        /// </summary>
+        /// <param name="assembly">Assembly to remove.</param>
+        public static void RemoveAssemblyFromCache(Assembly assembly) => cachedNonAbstractTypes.Remove(assembly);
+
         public static Option<TBase> ParseDerived<TBase, TInput>(TInput input) where TInput : notnull
         {
             static Option<TBase> none() => Option<TBase>.None();
@@ -60,4 +104,4 @@ namespace Barotrauma
             return derivedTypes.Select(parseOfType).FirstOrDefault(t => t.IsSome()) ?? none();
         }
     }
-}
+}