From 592dbac710f889323e664ca172f5a484dfbec7b2 Mon Sep 17 00:00:00 2001
From: Denis <93516910+Bussun@users.noreply.github.com>
Date: Fri, 28 Jan 2022 23:58:35 +0100
Subject: [PATCH] trying stuff

---
 BMGEditor/BMGEditor.csproj |   1 +
 BMGEditor/FS/Yaz0Stream.cs | 109 ++++++++++++++++++++++++++++++++++++-
 2 files changed, 109 insertions(+), 1 deletion(-)

diff --git a/BMGEditor/BMGEditor.csproj b/BMGEditor/BMGEditor.csproj
index 5edafe8..e5b7a5e 100644
--- a/BMGEditor/BMGEditor.csproj
+++ b/BMGEditor/BMGEditor.csproj
@@ -9,6 +9,7 @@
     <Platforms>AnyCPU;x64</Platforms>
     <PlatformTarget>x64</PlatformTarget>
     <ApplicationIcon>Luma_icon.ico</ApplicationIcon>
+    <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
   </PropertyGroup>
 
   <ItemGroup>
diff --git a/BMGEditor/FS/Yaz0Stream.cs b/BMGEditor/FS/Yaz0Stream.cs
index b3d2872..c62ad52 100644
--- a/BMGEditor/FS/Yaz0Stream.cs
+++ b/BMGEditor/FS/Yaz0Stream.cs
@@ -33,7 +33,114 @@ namespace BMGEditor
                 return;
 
             Int32 decompSize = (data[4] << 24 | data[5] << 16 | data[6] << 8 | data[7]);
-            
+            Byte[] output = new Byte[decompSize + 1];
+
+            /* Tryed rewriting it using szs tools code from MKW Wiki, not a real success
+            uint pos = 0x10;
+            uint outPos = 0x00;
+
+            byte group_head = 0;
+            int group_head_length = 0;
+
+            while (pos < data.Length && outPos < output.Length)
+            {
+                if (group_head_length == 0)
+                {
+                    group_head = data[pos];
+                    pos++;
+                    group_head_length = 8;
+                }
+                group_head_length--;
+                if ((group_head & 0x80) != 0)
+                {
+                    output[outPos] = data[pos];
+                    outPos++; pos++;
+                }
+                else
+                {
+                    byte b1 = data[pos]; pos++;
+                    byte b2 = data[pos]; pos++;
+
+                    uint copy_src = (uint)(outPos - ((b1 & 0x0F) << 8 | b2) - 1);
+                    int n = b1 >> 4;
+
+                    if (n == 0)
+                    {
+                        n = data[pos] + 0x12; pos++;
+                    }
+                    else
+                    {
+                        n += 2;
+                    }
+
+                    while (n-- < 0)
+                    {
+                        output[outPos] = output[copy_src];
+                    }
+                }
+                group_head <<= 1;
+            }
+            */
+
+            int Read_Position = 0x10;
+            int Write_Position = 0;
+            uint ValidBitCount = 0;
+            byte CurrentCodeByte = 0;
+
+            while (Write_Position < decompSize)
+            {
+                if (ValidBitCount == 0)
+                {
+                    CurrentCodeByte = data[Read_Position];
+                    ++Read_Position;
+                    ValidBitCount = 8;
+                }
+
+                if ((CurrentCodeByte & 0x80) != 0)
+                {
+                    output[Write_Position] = data[Read_Position];
+                    Write_Position++;
+                    Read_Position++;
+                }
+                else
+                {
+                    byte Byte1 = data[Read_Position];
+                    byte Byte2 = data[Read_Position + 1];
+                    Read_Position += 2;
+
+                    uint Dist = (uint)(((Byte1 & 0xF) << 8) | Byte2);
+                    uint CopySource = (uint)(Write_Position - Dist - 1);
+
+                    uint Byte_Count = (uint)(Byte1 >> 4);
+                    if (Byte_Count == 0)
+                    {
+                        Byte_Count = (uint)(data[Read_Position] + 0x12);
+                        Read_Position++;
+                    }
+                    else
+                    {
+                        Byte_Count += 1;
+                    }
+
+                    for (int i = 0; i < Byte_Count; ++i)
+                    {
+                        output[Write_Position] = output[CopySource];
+                        CopySource++;
+                        Write_Position++;
+                    }
+                }
+
+                CurrentCodeByte <<= 1;
+                ValidBitCount -= 1;
+            }
+
+            Array.Resize(ref data, decompSize + 1);
+            output.CopyTo(data, 0);
+
+            FileStream test = File.OpenWrite("./test.bin");
+            test.Write(output);
+            test.Flush();
+            test.Close();
             return;
         }
     }