From d4452ce3af1f419beefa0872e0058ba0151bb5a5 Mon Sep 17 00:00:00 2001
From: Kurt <kaphotics@gmail.com>
Date: Sun, 4 Oct 2020 14:42:48 -0700
Subject: [PATCH] SK2 coerce to load to a hint language

This format won't be supported cleanly, so let's just try to allow language detection to work as best as it can without storing metadata in the SK2 bytes.
---
 PKHeX.Core/PKM/SK2.cs                         | 26 ++++++++++++++++---
 PKHeX.Core/Saves/Util/SaveExtensions.cs       |  2 +-
 PKHeX.WinForms/Controls/PKM Editor/EditPK2.cs | 20 ++++++++++++++
 .../Controls/SAV Editor/SlotChangeManager.cs  |  2 +-
 4 files changed, 44 insertions(+), 6 deletions(-)

diff --git a/PKHeX.Core/PKM/SK2.cs b/PKHeX.Core/PKM/SK2.cs
index 3f7751b37..0846b9d3e 100644
--- a/PKHeX.Core/PKM/SK2.cs
+++ b/PKHeX.Core/PKM/SK2.cs
@@ -12,7 +12,8 @@ public sealed class SK2 : GBPKM, ICaughtData2
 
         public override int SIZE_PARTY => PokeCrypto.SIZE_2STADIUM;
         public override int SIZE_STORED => PokeCrypto.SIZE_2STADIUM;
-        public override bool Japanese { get; }
+        private bool _jp { get; set; }
+        public override bool Japanese => _jp;
         public override bool Korean => false;
         private const int StringLength = 12;
 
@@ -22,11 +23,11 @@ public sealed class SK2 : GBPKM, ICaughtData2
 
         public SK2(bool jp = false) : base(PokeCrypto.SIZE_2STADIUM)
         {
-            Japanese = jp;
+            _jp = jp;
         }
 
         public SK2(byte[] data) : this(data, IsJapanese(data)) { }
-        public SK2(byte[] data, bool jp) : base(data) => Japanese = jp;
+        public SK2(byte[] data, bool jp) : base(data) => _jp = jp;
 
         public override PKM Clone() => new SK2((byte[])Data.Clone(), Japanese)
         {
@@ -175,8 +176,25 @@ public PK2 ConvertToPK2()
             };
         }
 
-        private static bool IsJapanese(byte[] data) => StringConverter12.GetIsG1Japanese(data, 0x24, StringLength) && StringConverter12.GetIsG1Japanese(data, 0x30, StringLength);
+        private static bool IsJapanese(byte[] data)
+        {
+            if (!StringConverter12.GetIsG1Japanese(data, 0x24, StringLength))
+                return false;
+            if (!StringConverter12.GetIsG1Japanese(data, 0x30, StringLength))
+                return false;
+
+            for (int i = 6; i < 0xC; i++)
+            {
+                if (data[0x24 + i] != 0 && data[0x24 + i] != StringConverter12.G1TerminatorCode)
+                    return false;
+                if (data[0x30 + i] != 0 && data[0x30 + i] != StringConverter12.G1TerminatorCode)
+                    return false;
+            }
+            return true;
+        }
+
         private static bool IsEnglish(byte[] data) => StringConverter12.GetIsG1English(data, 0x24, StringLength) && StringConverter12.GetIsG1English(data, 0x30, StringLength);
         public bool IsPossible(bool japanese) => japanese ? IsJapanese(Data) : IsEnglish(Data);
+        public void SwapLanguage() => _jp ^= true;
     }
 }
diff --git a/PKHeX.Core/Saves/Util/SaveExtensions.cs b/PKHeX.Core/Saves/Util/SaveExtensions.cs
index ac26caf69..7c802a9f3 100644
--- a/PKHeX.Core/Saves/Util/SaveExtensions.cs
+++ b/PKHeX.Core/Saves/Util/SaveExtensions.cs
@@ -165,7 +165,7 @@ public static IEnumerable<PKM> GetCompatible(this SaveFile sav, IEnumerable<PKM>
                     continue;
                 }
 
-                if (sav is ILangDeviantSave il && PKMConverter.IsIncompatibleGB(pk, il.Japanese, pk.Japanese))
+                if (sav is ILangDeviantSave il && PKMConverter.IsIncompatibleGB(temp, il.Japanese, pk.Japanese))
                 {
                     c = PKMConverter.GetIncompatibleGBMessage(pk, il.Japanese);
                     Debug.WriteLine(c);
diff --git a/PKHeX.WinForms/Controls/PKM Editor/EditPK2.cs b/PKHeX.WinForms/Controls/PKM Editor/EditPK2.cs
index d764c7508..b751f3ac7 100644
--- a/PKHeX.WinForms/Controls/PKM Editor/EditPK2.cs	
+++ b/PKHeX.WinForms/Controls/PKM Editor/EditPK2.cs	
@@ -10,6 +10,11 @@ private void PopulateFieldsPK2()
             if (!(Entity is GBPKM pk2) || !(Entity is ICaughtData2 c2))
                 throw new FormatException(nameof(Entity));
 
+            if (Entity is SK2 sk2)
+            {
+                var sav = RequestSaveFile;
+                CoerceStadium2Language(sk2, sav);
+            }
             LoadMisc1(pk2);
             LoadMisc2(pk2);
 
@@ -25,6 +30,21 @@ private void PopulateFieldsPK2()
             UpdateStats();
         }
 
+        private static void CoerceStadium2Language(SK2 sk2, SaveFile sav)
+        {
+            if (sk2.Japanese == (sav.Language == 1))
+                return;
+
+            var la = new LegalityAnalysis(sk2);
+            if (la.Valid || !sk2.IsPossible(sav.Language == 1))
+                return;
+
+            sk2.SwapLanguage();
+            la = new LegalityAnalysis(sk2);
+            if (!la.Valid) // fail
+                sk2.SwapLanguage();
+        }
+
         private GBPKM PreparePK2()
         {
             if (!(Entity is GBPKM pk2) || !(Entity is ICaughtData2 c2))
diff --git a/PKHeX.WinForms/Controls/SAV Editor/SlotChangeManager.cs b/PKHeX.WinForms/Controls/SAV Editor/SlotChangeManager.cs
index 8a52db779..06d7e5cba 100644
--- a/PKHeX.WinForms/Controls/SAV Editor/SlotChangeManager.cs	
+++ b/PKHeX.WinForms/Controls/SAV Editor/SlotChangeManager.cs	
@@ -286,7 +286,7 @@ private bool TryLoadFiles(IReadOnlyList<string> files, DragEventArgs e, bool bad
             if (badDest && (pk.Species == 0 || pk.IsEgg))
                 return false;
 
-            if (sav is ILangDeviantSave il && PKMConverter.IsIncompatibleGB(pk, il.Japanese, pk.Japanese))
+            if (sav is ILangDeviantSave il && PKMConverter.IsIncompatibleGB(temp, il.Japanese, pk.Japanese))
             {
                 c = PKMConverter.GetIncompatibleGBMessage(pk, il.Japanese);
                 WinFormsUtil.Error(c);