[nostalgia/core] Add gc function to AssetManager

src/nostalgia/core/assetmanager.hpp

@@ -15,12 +15,15 @@
 
 namespace nostalgia::core {
 
+class AssetManager;
+
 template<typename T>
 class AssetRef;
 
 template<typename T>
 struct AssetContainer {
 
+	friend AssetManager;
 	friend AssetRef<T>;
 
 	private:
@@ -49,6 +52,10 @@ struct AssetContainer {
 			--m_references;
 		}
 
+		constexpr int references() const noexcept {
+			return m_references;
+		}
+
 };
 
 template<typename T>
@@ -128,6 +135,8 @@ class AssetManager {
 		class AssetTypeManagerBase {
 			public:
 				virtual ~AssetTypeManagerBase() = default;
+
+				virtual void gc() noexcept = 0;
 		};
 
 		template<typename T>
@@ -146,6 +155,15 @@ class AssetManager {
 					auto &p = m_cache[path] = ox::make_unique<AssetContainer<T>>(obj);
 					return AssetRef<T>(p.get());
 				}
+
+				void gc() noexcept final {
+					for (const auto &ack : m_cache.keys()) {
+						auto &ac = m_cache[ack];
+						if (ac->references()) {
+							m_cache.erase(ack);
+						}
+					}
+				}
 		};
 
 		ox::HashMap<ox::String, ox::UniquePtr<AssetTypeManagerBase>> m_assetTypeManagers;
@@ -178,6 +196,13 @@ class AssetManager {
 			auto m = getTypeManager<T>();
 			return m->setAsset(path, obj);
 		}
+
+		void gc() noexcept {
+			for (const auto &amk : m_assetTypeManagers.keys()) {
+				auto &am = m_assetTypeManagers[amk];
+				am->gc();
+			}
+		}
 };
 
 }