From a62db8de1d75c5c9759911fc53a7aeccea219e3b Mon Sep 17 00:00:00 2001
From: QwQ <59914293+Qv2ray-dev@users.noreply.github.com>
Date: Sun, 2 Aug 2020 09:04:52 +0800
Subject: [PATCH] fix: fixed #845

---
 makespec/BUILDVERSION     |  2 +-
 src/Qv2rayApplication.cpp | 15 +++++++++++----
 2 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/makespec/BUILDVERSION b/makespec/BUILDVERSION
index 6838a64c..d01f253a 100644
--- a/makespec/BUILDVERSION
+++ b/makespec/BUILDVERSION
@@ -1 +1 @@
-5819
+5820
diff --git a/src/Qv2rayApplication.cpp b/src/Qv2rayApplication.cpp
index 117d39bf..1398a059 100644
--- a/src/Qv2rayApplication.cpp
+++ b/src/Qv2rayApplication.cpp
@@ -396,11 +396,17 @@ namespace Qv2ray
         // Load config object from upgraded config QJsonObject
         auto confObject = Qv2rayConfigObject::fromJson(conf);
 
-        if (!Qv2rayTranslator->GetAvailableLanguages().contains(confObject.uiConfig.language))
+        const auto allTranslations = Qv2rayTranslator->GetAvailableLanguages();
+        const auto osLanguage = QLocale::system().name();
+        if (!allTranslations.contains(confObject.uiConfig.language) && allTranslations.contains(osLanguage))
         {
-            // Prevent empty.
-            LOG(MODULE_UI, "Setting default UI language to system locale.")
-            confObject.uiConfig.language = QLocale::system().name();
+            // If configured language is not found. Set to system language.
+            LOG(MODULE_UI, "Fall back language setting to: " + osLanguage)
+            confObject.uiConfig.language = osLanguage;
+        }
+        else if (!allTranslations.isEmpty())
+        {
+            confObject.uiConfig.language = allTranslations.first();
         }
 
         if (!Qv2rayTranslator->InstallTranslation(confObject.uiConfig.language))
@@ -409,6 +415,7 @@ namespace Qv2ray
                              "Cannot load translation for " + confObject.uiConfig.language + NEWLINE + //
                                  "English is now used." + NEWLINE + NEWLINE +                          //
                                  "Please go to Preferences Window to change language or open an Issue");
+            confObject.uiConfig.language = "en_US";
         }
 
         // Let's save the config.