Materials: Model Manager External Interface (#20825)

* Materials: Model Manager External Interface

Implement the ModelManagerExternal class for the external Materials
interface.

This is part of the ongoing merges of code to support external material
interfaces. In this PR the ModelManagerExternal class is implemented,
along with changes to supporting classes required for this class.

* Apply reviewer feedback

src/Mod/Material/App/ModelManagerExternal.cpp

@@ -0,0 +1,187 @@
+/***************************************************************************
+ *   Copyright (c) 2024 David Carter <dcarter@david.carter.ca>             *
+ *                                                                         *
+ *   This file is part of FreeCAD.                                         *
+ *                                                                         *
+ *   FreeCAD is free software: you can redistribute it and/or modify it    *
+ *   under the terms of the GNU Lesser General Public License as           *
+ *   published by the Free Software Foundation, either version 2.1 of the  *
+ *   License, or (at your option) any later version.                       *
+ *                                                                         *
+ *   FreeCAD is distributed in the hope that it will be useful, but        *
+ *   WITHOUT ANY WARRANTY; without even the implied warranty of            *
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU      *
+ *   Lesser General Public License for more details.                       *
+ *                                                                         *
+ *   You should have received a copy of the GNU Lesser General Public      *
+ *   License along with FreeCAD. If not, see                               *
+ *   <https://www.gnu.org/licenses/>.                                      *
+ *                                                                         *
+ **************************************************************************/
+
+#include "PreCompiled.h"
+#ifndef _PreComp_
+#endif
+
+#include <QMutexLocker>
+
+#include <App/Application.h>
+
+#include "Model.h"
+#include "ModelLoader.h"
+#include "ModelManagerExternal.h"
+#include "ExternalManager.h"
+
+using namespace Materials;
+
+QMutex ModelManagerExternal::_mutex;
+LRU::Cache<std::string, std::shared_ptr<Model>> ModelManagerExternal::_cache(DEFAULT_CACHE_SIZE);
+
+TYPESYSTEM_SOURCE(Materials::ModelManagerExternal, Base::BaseClass)
+
+ModelManagerExternal::ModelManagerExternal()
+{
+    initCache();
+}
+
+void ModelManagerExternal::initCache()
+{
+    QMutexLocker locker(&_mutex);
+
+    ParameterGrp::handle hGrp = App::GetApplication().GetParameterGroupByPath(
+        "User parameter:BaseApp/Preferences/Mod/Material/ExternalInterface");
+    auto cacheSize = hGrp->GetInt("ModelCacheSize", DEFAULT_CACHE_SIZE);
+    _cache.capacity(cacheSize);
+
+    _cache.monitor();
+}
+
+void ModelManagerExternal::cleanup()
+{
+}
+
+void ModelManagerExternal::refresh()
+{
+    resetCache();
+}
+
+//=====
+//
+// Library management
+//
+//=====
+
+std::shared_ptr<std::list<std::shared_ptr<ModelLibrary>>> ModelManagerExternal::getLibraries()
+{
+    auto libraryList = std::make_shared<std::list<std::shared_ptr<ModelLibrary>>>();
+    try {
+        auto externalLibraries = ExternalManager::getManager()->libraries();
+        for (auto& entry : *externalLibraries) {
+            auto library = std::make_shared<ModelLibrary>(*entry);
+            libraryList->push_back(library);
+        }
+    }
+    catch (const LibraryNotFound& e) {
+    }
+    catch (const ConnectionError& e) {
+    }
+
+    return libraryList;
+}
+
+std::shared_ptr<ModelLibrary> ModelManagerExternal::getLibrary(const QString& name) const
+{
+    try {
+        auto lib = ExternalManager::getManager()->getLibrary(name);
+        auto library = std::make_shared<ModelLibrary>(*lib);
+        return library;
+    }
+    catch (const LibraryNotFound& e) {
+        throw LibraryNotFound(e);
+    }
+    catch (const ConnectionError& e) {
+        throw LibraryNotFound(e.what());
+    }
+}
+
+void ModelManagerExternal::createLibrary(const QString& libraryName,
+                                      const QString& icon,
+                                      bool readOnly)
+{
+    ExternalManager::getManager()->createLibrary(libraryName, icon, readOnly);
+}
+
+std::shared_ptr<std::vector<std::tuple<QString, QString, QString>>>
+ModelManagerExternal::libraryModels(const QString& libraryName)
+{
+    return ExternalManager::getManager()->libraryModels(libraryName);
+}
+
+//=====
+//
+// Model management
+//
+//=====
+
+std::shared_ptr<Model> ModelManagerExternal::getModel(const QString& uuid)
+{
+    if (_cache.contains(uuid.toStdString())) {
+        return _cache.lookup(uuid.toStdString());
+    }
+    try
+    {
+        auto model = ExternalManager::getManager()->getModel(uuid);
+        _cache.emplace(uuid.toStdString(), model);
+        return model;
+    }
+    catch (const ModelNotFound& e) {
+        _cache.emplace(uuid.toStdString(), nullptr);
+        return nullptr;
+    }
+    catch (const ConnectionError& e) {
+        _cache.emplace(uuid.toStdString(), nullptr);
+        return nullptr;
+    }
+}
+
+std::shared_ptr<std::map<QString, std::shared_ptr<Model>>> ModelManagerExternal::getModels()
+{
+    // TODO: Implement an external call
+    return std::make_shared<std::map<QString, std::shared_ptr<Model>>>();
+}
+
+void ModelManagerExternal::addModel(const QString& libraryName,
+                                    const QString& path,
+                                    const std::shared_ptr<Model>& model)
+{
+    _cache.erase(model->getUUID().toStdString());
+    ExternalManager::getManager()->addModel(libraryName, path, model);
+}
+
+void ModelManagerExternal::migrateModel(const QString& libraryName,
+                                    const QString& path,
+                                    const std::shared_ptr<Model>& model)
+{
+    _cache.erase(model->getUUID().toStdString());
+    ExternalManager::getManager()->migrateModel(libraryName, path, model);
+}
+
+//=====
+//
+// Cache management
+//
+//=====
+
+void ModelManagerExternal::resetCache()
+{
+    _cache.clear();
+}
+
+double ModelManagerExternal::modelHitRate()
+{
+    auto hitRate = _cache.stats().hit_rate();
+    if (std::isnan(hitRate)) {
+        return 0;
+    }
+    return hitRate;
+}