From af33e341bd577b1a8838b5fd5936b4f7ebdb36e5 Mon Sep 17 00:00:00 2001
From: ragnarok-clanker <ragnarok-clanker>
Date: Sun, 1 Nov 2026 03:05:46 +0000
Subject: [PATCH] Decompile fn_17811 (InitializeLanguage)

Batch #9151 by KWDev: 0 byte-identical, 1 confirmed by peer review.

- fn_17811 InitializeLanguage: logic confirmed by peer review

Peer-reviewed-by: youko, superintelligence
Accepted without human review: peers confirmed the logic ("same" ahead by at least 3, with 70% of the votes).
---
 Source/Client/Input/InputCharset.h            |  26 +++++
 .../Configuration/ServiceConfiguration.cpp    | 108 +++++++++++++++++-
 2 files changed, 132 insertions(+), 2 deletions(-)

diff --git a/Source/Client/Input/InputCharset.h b/Source/Client/Input/InputCharset.h
index 5b2e0f27..81c06f4a 100644
--- a/Source/Client/Input/InputCharset.h
+++ b/Source/Client/Input/InputCharset.h
@@ -27,6 +27,32 @@ static_assert(offsetof(InputCharset, servicePrefix) == 0x9C);
 static_assert(offsetof(InputCharset, alternateLanguage) == 0xB4);
 #endif
 
+struct DefaultInputCharset : InputCharset {
+  DefaultInputCharset();
+  ~DefaultInputCharset();
+};
+
+struct TraditionalChineseInputCharset : InputCharset {
+  /* 00B8 */ unsigned char unknown_00B8[0x40C];
+
+  TraditionalChineseInputCharset();
+  ~TraditionalChineseInputCharset();
+};
+
+struct ThaiInputCharset : InputCharset {
+  /* 00B8 */ bool unknown_00B8;
+
+  ThaiInputCharset();
+  ~ThaiInputCharset();
+};
+
+struct ArabicInputCharset : InputCharset {
+  /* 00B8 */ bool unknown_00B8;
+
+  ArabicInputCharset();
+  ~ArabicInputCharset();
+};
+
 extern InputCharset* g_serverLanguage;
 
 #endif
diff --git a/Source/Contents/Configuration/ServiceConfiguration.cpp b/Source/Contents/Configuration/ServiceConfiguration.cpp
index 8a6d080a..d5375bce 100644
--- a/Source/Contents/Configuration/ServiceConfiguration.cpp
+++ b/Source/Contents/Configuration/ServiceConfiguration.cpp
@@ -13,6 +13,7 @@
 #include "Resource/ResourceMgr.h"
 #include "Resource/XmlNode.h"
 #include "UI/Text/UIBalloonText.h"
+#include "Utility/Text/TextTokens.h"
 #include "Utility/Cipher/XorBytes.h"
 
 #include <cstddef>
@@ -136,7 +137,7 @@ const char* GetLicenceText() {
 }
 
 void sub_AD1270();
-void sub_AD1780();
+void InitializeLanguage();
 
 // OFFSET: 0x00ACFF90
 // FUNCTION: fn_17808
@@ -173,7 +174,7 @@ void InitializeServiceStrings() {
   }
   }
 
-  sub_AD1780();
+  InitializeLanguage();
 
   if (g_serviceType == 0 || g_serviceType == 6) {
     g_nameBalloonFontHeight = 13;
@@ -324,6 +325,109 @@ void sub_AD1270() {
   }
 }
 
+// OFFSET: 0x00AD1780
+// FUNCTION: fn_17811
+void InitializeLanguage() {
+  // GLOBAL: gl_25359
+  static DefaultInputCharset defaultCharset;
+  // GLOBAL: gl_25360
+  static TraditionalChineseInputCharset traditionalChineseCharset;
+  // GLOBAL: gl_25361
+  static ThaiInputCharset thaiCharset;
+  // GLOBAL: gl_25362
+  static ArabicInputCharset arabicCharset;
+
+  switch (g_serviceType) {
+  case 0:
+    g_language = 0;
+    g_textCodePage = 949;
+    g_serverLanguage = &defaultCharset;
+    break;
+  case 2:
+    g_language = 2;
+    g_textCodePage = 932;
+    g_serverLanguage = &defaultCharset;
+    break;
+  case 3:
+    g_language = 3;
+    g_serverLanguage = &traditionalChineseCharset;
+    g_textCodePage = 936;
+    break;
+  case 4:
+    g_language = 4;
+    g_serverLanguage = &traditionalChineseCharset;
+    g_textCodePage = 950;
+    break;
+  case 5:
+    g_language = 5;
+    g_serverLanguage = &thaiCharset;
+    g_textCodePage = 874;
+    break;
+  case 10:
+    g_language = 1;
+    g_inlineCharset = 1;
+    g_textCodePage = 0;
+    g_serverLanguage = &defaultCharset;
+    break;
+  case 11:
+    g_language = 1;
+    g_inlineCharset = 0;
+    g_textCodePage = 0;
+    g_serverLanguage = &defaultCharset;
+    break;
+  case 12:
+  case 18:
+    g_language = 6;
+    g_inlineCharset = 0;
+    g_textCodePage = 1252;
+    g_serverLanguage = &defaultCharset;
+    break;
+  case 14:
+    g_language = 1;
+    g_inlineCharset = 0;
+    g_textCodePage = 1251;
+    g_serverLanguage = &defaultCharset;
+    break;
+  case 15:
+    g_language = 7;
+    g_inlineCharset = 0;
+    g_textCodePage = 1258;
+    g_serverLanguage = &defaultCharset;
+    break;
+  case 17:
+    g_language = 1;
+    g_inlineCharset = 0;
+    g_textCodePage = 1145;
+    g_serverLanguage = &defaultCharset;
+    break;
+  case 19:
+    g_language = 12;
+    g_serverLanguage = &arabicCharset;
+    g_textCodePage = 1256;
+    break;
+  default: {
+    const std::uint8_t source[] = {0xF9, 0x1E, 0x87, 0xD1, 0x00, 0x4D, 0xE4, 0x2E, 0xF6, 0x16, 0xC2, 0x9D,
+                                   0x12, 0x46, 0xF7, 0x2F, 0xFE, 0x1F, 0xC0, 0x9D, 0x40, 0x02, 0xA2, 0x5B};
+    ShowErrorDialog(GetRenderSystemHolder()->system, DecryptText<0x5B832361BDA77197ULL>(source), 0);
+  }
+  case 1:
+  case 6:
+  case 7:
+  case 8:
+  case 9:
+  case 13:
+  case 20:
+    g_textCodePage = 0;
+    g_language = 1;
+    g_serverLanguage = &defaultCharset;
+    break;
+  }
+
+  if (g_serviceMode == 3) {
+    g_inlineCharset = 1;
+  }
+}
+
 // OFFSET: 0x00AD2A00
 // FUNCTION: fn_17818
 void ReadClientInfo(XmlNode* clientInfo) {