From 39c3a0eea700231253ababe2c340dcb5967f41d0 Mon Sep 17 00:00:00 2001
From: Kurt <kaphotics@gmail.com>
Date: Sun, 16 Sep 2018 13:57:09 -0700
Subject: [PATCH] Rework sav3 version detect

Might still be flaky for FRLG, but can now (99.99999999%) determine RS
vs E...
---
 PKHeX.Core/Saves/SAV3.cs          | 36 ++++++++++++++++++++++++-------
 PKHeX.Core/Saves/Util/SaveUtil.cs | 11 +---------
 2 files changed, 29 insertions(+), 18 deletions(-)

diff --git a/PKHeX.Core/Saves/SAV3.cs b/PKHeX.Core/Saves/SAV3.cs
index cb4b13056..b6db8871c 100644
--- a/PKHeX.Core/Saves/SAV3.cs
+++ b/PKHeX.Core/Saves/SAV3.cs
@@ -72,14 +72,6 @@ public SAV3(byte[] data = null, GameVersion versionOverride = GameVersion.Any)
             BAK = (byte[])Data.Clone();
             Exportable = !IsRangeEmpty(0, Data.Length);
 
-            if (data == null)
-                Version = GameVersion.FRLG;
-            else if (versionOverride != GameVersion.Any)
-                Version = versionOverride;
-            else Version = SaveUtil.GetIsG3SAV(Data);
-            if (Version == GameVersion.Invalid)
-                return;
-
             int[] BlockOrder1 = GetBlockOrder(0);
             if (Data.Length > SaveUtil.SIZE_G3RAWHALF)
             {
@@ -100,6 +92,13 @@ public SAV3(byte[] data = null, GameVersion versionOverride = GameVersion.Any)
                 BlockOfs[i] = index < 0 ? int.MinValue : (index * SIZE_BLOCK) + ABO;
             }
 
+            if (data == null)
+                Version = GameVersion.FRLG;
+            else if (versionOverride != GameVersion.Any)
+                Version = versionOverride;
+            else
+                Version = GetVersion(Data, BlockOfs[0]);
+
             // Set up PC data buffer beyond end of save file.
             Box = Data.Length;
             Array.Resize(ref Data, Data.Length + SIZE_RESERVED); // More than enough empty space.
@@ -197,6 +196,27 @@ private int GetActiveSaveIndex(int[] BlockOrder1, int[] BlockOrder2)
             return count1 > count2 ? 0 : 1;
         }
 
+        public static GameVersion GetVersion(byte[] data, int block0Ofs)
+        {
+            uint GameCode = BitConverter.ToUInt32(data, block0Ofs + 0xAC);
+            switch (GameCode)
+            {
+                case 1: return GameVersion.FRLG; // fixed value
+                case 0: return GameVersion.RS; // no battle tower record data
+                case uint.MaxValue: return GameVersion.Unknown; // what a hack
+                default:
+                    // Ruby doesn't set data as far down as Emerald.
+                    // 00 FF 00 00 00 00 00 00 00 FF 00 00 00 00 00 00
+                    // ^ byte pattern in Emerald saves, is all zero in Ruby/Sapphire as far as I can tell.
+                    // Some saves have had data @ 0x550
+                    if (BitConverter.ToUInt64(data, block0Ofs + 0xEE0) != 0)
+                        return GameVersion.E;
+                    if (BitConverter.ToUInt64(data, block0Ofs + 0xEE8) != 0)
+                        return GameVersion.E;
+                    return GameVersion.RS;
+            }
+        }
+
         protected override byte[] Write(bool DSV)
         {
             // Copy Box data back
diff --git a/PKHeX.Core/Saves/Util/SaveUtil.cs b/PKHeX.Core/Saves/Util/SaveUtil.cs
index f1764836b..e5e8b7326 100644
--- a/PKHeX.Core/Saves/Util/SaveUtil.cs
+++ b/PKHeX.Core/Saves/Util/SaveUtil.cs
@@ -237,16 +237,7 @@ internal static GameVersion GetIsG3SAV(byte[] data)
                     continue;
                 if (BlockOrder.Count(v => v == 0) == BlockOrder.Length)
                     continue;
-                uint GameCode = BitConverter.ToUInt32(data, (Block0 * 0x1000) + 0xAC + ofs);
-                switch (GameCode)
-                {
-                    case 0: return GameVersion.RS;
-                    case 1: return GameVersion.FRLG;
-                    case uint.MaxValue: return GameVersion.Unknown;  // what a hack
-                    default: return BitConverter.ToUInt32(data, (Block0 * 0x1000) + 0x1F4 + ofs) == 0
-                            ? GameVersion.RS
-                            : GameVersion.E;
-                }
+                return SAV3.GetVersion(data, (0x1000 * Block0) + ofs);
             }
             return GameVersion.Invalid;
         }