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Source/Engine/Engine/EngineService.cpp

@@ -0,0 +1,101 @@
+// Copyright (c) 2012-2020 Wojciech Figat. All rights reserved.
+
+#include "EngineService.h"
+#include "Engine/Core/Log.h"
+#include "Engine/Core/Collections/Array.h"
+#include "Engine/Core/Collections/Sorting.h"
+
+static bool CompareEngineServices(EngineService* const& a, EngineService* const& b)
+{
+    return a->Order < b->Order;
+}
+
+#define DEFINE_ENGINE_SERVICE_EVENT(name) \
+    void EngineService::name() { } \
+    void EngineService::On##name() \
+    { \
+        auto& services = GetServices(); \
+        for (int32 i = 0; i < services.Count(); i++) \
+            services[i]->name(); \
+    }
+#define DEFINE_ENGINE_SERVICE_EVENT_INVERTED(name) \
+    void EngineService::name() { } \
+    void EngineService::On##name() \
+    { \
+        auto& services = GetServices(); \
+        for (int32 i = 0; i < services.Count(); i++) \
+            services[i]->name(); \
+    }
+
+DEFINE_ENGINE_SERVICE_EVENT(FixedUpdate);
+DEFINE_ENGINE_SERVICE_EVENT(Update);
+DEFINE_ENGINE_SERVICE_EVENT(LateUpdate);
+DEFINE_ENGINE_SERVICE_EVENT(Draw);
+DEFINE_ENGINE_SERVICE_EVENT_INVERTED(BeforeExit);
+
+EngineService::EngineServicesArray& EngineService::GetServices()
+{
+    static EngineServicesArray Services;
+    return Services;
+}
+
+void EngineService::Sort()
+{
+    auto& services = GetServices();
+    Sorting::QuickSort(services.Get(), services.Count(), &CompareEngineServices);
+}
+
+EngineService::EngineService(const Char* name, int32 order)
+{
+    Name = name;
+    Order = order;
+
+    auto& services = GetServices();
+    services.Add(this);
+    if (services.First()->IsInitialized)
+        Sort();
+}
+
+bool EngineService::Init()
+{
+    return false;
+}
+
+void EngineService::OnInit()
+{
+    Sort();
+
+    // Init services from front to back
+    auto& services = GetServices();
+    for (int32 i = 0; i < services.Count(); i++)
+    {
+        const auto service = services[i];
+        LOG(Info, "Initialize {0}...", service->Name);
+        service->IsInitialized = true;
+        if (service->Init())
+        {
+            Platform::Fatal(String::Format(TEXT("Failed to initialize {0}."), service->Name));
+        }
+    }
+
+    LOG(Info, "Engine services are ready!");
+}
+
+void EngineService::Dispose()
+{
+}
+
+void EngineService::OnDispose()
+{
+    // Dispose services from back to front
+    auto& services = GetServices();
+    for (int32 i = services.Count() - 1; i >= 0; i--)
+    {
+        const auto service = services[i];
+        if (service->IsInitialized)
+        {
+            service->IsInitialized = false;
+            service->Dispose();
+        }
+    }
+}