2 files changed, 62 insertions, 2 deletions

diff --git a/src/core/hle/service/cfg/cfg.cpp b/src/core/hle/service/cfg/cfg.cpp
index 65655f45d..0bf59eb76 100644
--- a/src/core/hle/service/cfg/cfg.cpp
+++ b/src/core/hle/service/cfg/cfg.cpp
@@ -115,6 +115,8 @@ static const std::vector<u8> cfg_system_savedata_id = {
     0x00, 0x00, 0x00, 0x00, 0x17, 0x00, 0x01, 0x00,
 };
 
+static u32 preferred_region_code = 0;
+
 void GetCountryCodeString(Service::Interface* self) {
     u32* cmd_buff = Kernel::GetCommandBuffer();
     u32 country_code_id = cmd_buff[1];
@@ -160,11 +162,18 @@ void GetCountryCodeID(Service::Interface* self) {
     cmd_buff[2] = country_code_id;
 }
 
+static u32 GetRegionValue() {
+    if (Settings::values.region_value == Settings::REGION_VALUE_AUTO_SELECT)
+        return preferred_region_code;
+
+    return Settings::values.region_value;
+}
+
 void SecureInfoGetRegion(Service::Interface* self) {
     u32* cmd_buff = Kernel::GetCommandBuffer();
 
     cmd_buff[1] = RESULT_SUCCESS.raw;
-    cmd_buff[2] = Settings::values.region_value;
+    cmd_buff[2] = GetRegionValue();
 }
 
 void GenHashConsoleUnique(Service::Interface* self) {
@@ -184,7 +193,7 @@ void GetRegionCanadaUSA(Service::Interface* self) {
     cmd_buff[1] = RESULT_SUCCESS.raw;
 
     u8 canada_or_usa = 1;
-    if (canada_or_usa == Settings::values.region_value) {
+    if (canada_or_usa == GetRegionValue()) {
         cmd_buff[2] = 1;
     } else {
         cmd_buff[2] = 0;
@@ -314,10 +323,47 @@ static ResultVal<void*> GetConfigInfoBlockPointer(u32 block_id, u32 size, u32 fl
     return MakeResult<void*>(pointer);
 }
 
+/// Checks if the language is available in the chosen region, and returns a proper one
+static u8 AdjustLanguageInfoBlock(u32 region, u8 language) {
+    static const std::array<std::vector<u8>, 7> region_languages{{
+        // JPN
+        {LANGUAGE_JP},
+        // USA
+        {LANGUAGE_EN, LANGUAGE_FR, LANGUAGE_ES, LANGUAGE_PT},
+        // EUR
+        {LANGUAGE_EN, LANGUAGE_FR, LANGUAGE_DE, LANGUAGE_IT, LANGUAGE_ES, LANGUAGE_NL, LANGUAGE_PT,
+         LANGUAGE_RU},
+        // AUS
+        {LANGUAGE_EN, LANGUAGE_FR, LANGUAGE_DE, LANGUAGE_IT, LANGUAGE_ES, LANGUAGE_NL, LANGUAGE_PT,
+         LANGUAGE_RU},
+        // CHN
+        {LANGUAGE_ZH},
+        // KOR
+        {LANGUAGE_KO},
+        // TWN
+        {LANGUAGE_TW},
+    }};
+    const auto& available = region_languages[region];
+    if (std::find(available.begin(), available.end(), language) == available.end()) {
+        return available[0];
+    }
+    return language;
+}
+
 ResultCode GetConfigInfoBlock(u32 block_id, u32 size, u32 flag, void* output) {
     void* pointer;
     CASCADE_RESULT(pointer, GetConfigInfoBlockPointer(block_id, size, flag));
     memcpy(output, pointer, size);
+
+    // override the language setting if the region setting is auto
+    if (block_id == LanguageBlockID &&
+        Settings::values.region_value == Settings::REGION_VALUE_AUTO_SELECT) {
+        u8 language;
+        memcpy(&language, output, sizeof(u8));
+        language = AdjustLanguageInfoBlock(preferred_region_code, language);
+        memcpy(output, &language, sizeof(u8));
+    }
+
     return RESULT_SUCCESS;
 }
 
@@ -535,10 +581,17 @@ void Init() {
     AddService(new CFG_U);
 
     LoadConfigNANDSaveFile();
+
+    preferred_region_code = 0;
 }
 
 void Shutdown() {}
 
+void SetPreferredRegionCode(u32 region_code) {
+    preferred_region_code = region_code;
+    LOG_INFO(Service_CFG, "Preferred region code set to %u", preferred_region_code);
+}
+
 void SetUsername(const std::u16string& name) {
     ASSERT(name.size() <= 10);
     UsernameBlock block{};
diff --git a/src/core/hle/service/cfg/cfg.h b/src/core/hle/service/cfg/cfg.h
index fb47c2aa5..618c9647e 100644
--- a/src/core/hle/service/cfg/cfg.h
+++ b/src/core/hle/service/cfg/cfg.h
@@ -282,6 +282,13 @@ void Init();
 /// Shutdown the config service
 void Shutdown();
 
+/**
+ * Set the region code preferred by the game so that CFG will adjust to it when the region setting
+ * is auto.
+ * @param region_code the preferred region code to set
+ */
+void SetPreferredRegionCode(u32 region_code);
+
 // Utilities for frontend to set config data.
 // Note: before calling these functions, LoadConfigNANDSaveFile should be called,
 // and UpdateConfigNANDSavegame should be called after making changes to config data.