refactor: unify model source and weight lifecycle management (#1956)

src/extensions/generation_extension.h

@@ -19,7 +19,7 @@ struct GenerationExtensionInitContext {
     const sd_ctx_params_t* params;
     SDVersion version;
     const String2TensorStorage& tensor_storage_map;
-    ModelLoader& model_loader;
+    bool photomaker_source_available;
     std::shared_ptr<ModelManager> model_manager;
     int n_threads;
     std::function<bool(SDBackendModule)> ensure_backend_pair;
@@ -39,7 +39,8 @@ struct GenerationExtensionConditionContext {
 struct GenerationExtension {
     virtual ~GenerationExtension() = default;
 
-    virtual const char* name() const = 0;
+    virtual ModelComponent component() const = 0;
+    const char* name() const { return model_component_name(component()); }
     virtual bool is_enabled() const {
         return false;
     }

src/extensions/photomaker_extension.cpp

@@ -109,8 +109,8 @@ struct PhotoMakerExtension : public GenerationExtension {
     SDCondition id_condition;
     int start_merge_step = -1;
 
-    const char* name() const override {
-        return "photomaker";
+    ModelComponent component() const override {
+        return ModelComponent::PhotoMaker;
     }
 
     bool is_enabled() const override {
@@ -119,7 +119,7 @@ struct PhotoMakerExtension : public GenerationExtension {
 
     bool init(const GenerationExtensionInitContext& ctx) override {
         model_path = SAFE_STR(ctx.params->photo_maker_path);
-        if (model_path.empty()) {
+        if (model_path.empty() || !ctx.photomaker_source_available) {
             return true;
         }
 
@@ -128,13 +128,7 @@ struct PhotoMakerExtension : public GenerationExtension {
         }
 
         PMVersion pm_version = std::strstr(model_path.c_str(), "v2") != nullptr ? PM_VERSION_2 : PM_VERSION_1;
-        LOG_INFO("loading stacked ID embedding (PHOTOMAKER) model file from '%s'", model_path.c_str());
-        if (!ctx.model_loader.init_from_file_and_convert_name(model_path, "pmid.")) {
-            LOG_WARN("loading stacked ID embedding from '%s' failed", model_path.c_str());
-            return true;
-        }
-
-        pmid_model = std::make_shared<PhotoMakerIDEncoder>(ctx.backend_for(SDBackendModule::PHOTOMAKER),
+        pmid_model           = std::make_shared<PhotoMakerIDEncoder>(ctx.backend_for(SDBackendModule::PHOTOMAKER),
                                                            ctx.tensor_storage_map,
                                                            "pmid",
                                                            ctx.version,

src/extensions/pulid_extension.cpp

@@ -79,8 +79,8 @@ struct PuLIDExtension : public GenerationExtension {
     sd::Tensor<float> id_embedding;
     float id_weight = 1.0f;
 
-    const char* name() const override {
-        return "pulid";
+    ModelComponent component() const override {
+        return ModelComponent::PuLID;
     }
 
     bool is_enabled() const override {