Add localization string tables caching for current language

Source/Engine/Localization/Localization.cpp

@@ -7,29 +7,38 @@
 #include "Engine/Core/Config/GameSettings.h"
 #include "Engine/Engine/EngineService.h"
 #include "Engine/Content/Content.h"
+#include "Engine/Profiler/ProfilerCPU.h"
 #include "Engine/Serialization/Serialization.h"
 
 class LocalizationService : public EngineService
 {
 public:
+    CultureInfo CurrentCulture;
+    CultureInfo CurrentLanguage;
+    Array<AssetReference<LocalizedStringTable>> LocalizedStringTables;
+
     LocalizationService()
-        : EngineService(TEXT("Localization"), -950)
+        : EngineService(TEXT("Localization"), -500)
+        , CurrentCulture(0)
+        , CurrentLanguage(0)
     {
     }
 
+    void OnLocalizationChanged();
+
     bool Init() override;
 };
 
 namespace
 {
-    CultureInfo CurrentCulture(0);
-    CultureInfo CurrentLanguage(0);
-    LocalizationService LocalizationServiceInstance;
+    LocalizationService Instance;
+}
 
 IMPLEMENT_SETTINGS_GETTER(LocalizationSettings, Localization);
 
 void LocalizationSettings::Apply()
 {
+    Instance.OnLocalizationChanged();
 }
 
 void LocalizationSettings::Deserialize(DeserializeStream& stream, ISerializeModifier* modifier)
@@ -37,11 +46,68 @@ void LocalizationSettings::Deserialize(DeserializeStream& stream, ISerializeModi
     DESERIALIZE(LocalizedStringTables);
 }
 
+void LocalizationService::OnLocalizationChanged()
+{
+    PROFILE_CPU();
+
+    Instance.LocalizedStringTables.Clear();
+
+    // Collect all localization tables into mapping locale -> tables
+    auto& settings = *LocalizationSettings::Get();
+    Dictionary<String, Array<AssetReference<LocalizedStringTable>, InlinedAllocation<8>>> tables;
+    for (auto& e : settings.LocalizedStringTables)
+    {
+        auto table = e.Get();
+        if (table && !table->WaitForLoaded())
+        {
+            tables[table->Locale].Add(table);
+        }
+    }
+
+    // Pick localization tables for a current language
+    auto* table = tables.TryGet(Instance.CurrentLanguage.GetName());
+    if (!table)
+    {
+        // Try using parent culture (eg. en if en-GB is missing)
+        const CultureInfo parentLanguage(Instance.CurrentLanguage.GetParentLCID());
+        if (parentLanguage.GetName().HasChars())
+            table = tables.TryGet(parentLanguage.GetName());
+        if (!table)
+        {
+            // Fallback to English
+            const CultureInfo english("en");
+            table = tables.TryGet(english.GetName());
+        }
+    }
+
+    // Apply localization table
+    if (table)
+    {
+        String locale;
+        for (auto& e : tables)
+        {
+            if (&e.Value == table)
+            {
+                locale = e.Key;
+                break;
+            }
+        }
+        LOG(Info, "Using localization for {0}", locale);
+        Instance.LocalizedStringTables.Add(table->Get(), table->Count());
+    }
+
+    // Send event
+    Localization::LocalizationChanged();
 }
 
 bool LocalizationService::Init()
 {
+    // Use system language as default
     CurrentLanguage = CurrentCulture = CultureInfo(Platform::GetUserLocaleName());
+
+    // Setup localization
+    Instance.OnLocalizationChanged();
+
     return false;
 }
 
@@ -49,41 +115,41 @@ Delegate<> Localization::LocalizationChanged;
 
 const CultureInfo& Localization::GetCurrentCulture()
 {
-    return CurrentCulture;
+    return Instance.CurrentCulture;
 }
 
 void Localization::SetCurrentCulture(const CultureInfo& value)
 {
-    if (CurrentCulture == value)
+    if (Instance.CurrentCulture == value)
         return;
 
     LOG(Info, "Changing current culture to: {0} ({1})", value.GetName(), value.GetLCID());
-    CurrentCulture = value;
-    LocalizationChanged();
+    Instance.CurrentCulture = value;
+    Instance.OnLocalizationChanged();
 }
 
 const CultureInfo& Localization::GetCurrentLanguage()
 {
-    return CurrentLanguage;
+    return Instance.CurrentLanguage;
 }
 
 void Localization::SetCurrentLanguage(const CultureInfo& value)
 {
-    if (CurrentLanguage == value)
+    if (Instance.CurrentLanguage == value)
         return;
 
     LOG(Info, "Changing current language to: {0} ({1})", value.GetName(), value.GetLCID());
-    CurrentLanguage = value;
-    LocalizationChanged();
+    Instance.CurrentLanguage = value;
+    Instance.OnLocalizationChanged();
 }
 
 void Localization::SetCurrentLanguageCulture(const CultureInfo& value)
 {
-    if (CurrentCulture == value && CurrentLanguage == value)
+    if (Instance.CurrentCulture == value && Instance.CurrentLanguage == value)
         return;
 
     LOG(Info, "Changing current language and culture to: {0} ({1})", value.GetName(), value.GetLCID());
-    CurrentCulture = value;
-    CurrentLanguage = value;
-    LocalizationChanged();
+    Instance.CurrentCulture = value;
+    Instance.CurrentLanguage = value;
+    Instance.OnLocalizationChanged();
 }