Add methods for getting file data from the vfs (#1)

.gitignore

@@ -224,3 +224,4 @@ AppPackages/
 #####
 # End of core ignore list, below put you custom 'per project' settings (patterns or path)
 #####
+/GalanthusCli/Properties/launchSettings.json

Galanthus/GameManager.cs

@@ -130,4 +130,21 @@ public static bool LoadGame(string inDirectory, Platform inPlatform, Compression
 
         return true;
     }
+    public static Block<byte> GetFileBytesFromPath(string filePath, string inDirectory)
+    {
+        string dataDir = Path.Combine(inDirectory, CodeName, "sdf", Platform.ToString().ToLower(), "data");
+        Block<byte> data = null;
+        if (filePath != null)
+        {
+            foreach (Structs.File file in m_toc.Files)
+            {
+                if (file.Name == filePath)
+                {
+                    data = m_toc.GetFileBytes(file, dataDir);
+                    break;
+                }
+            }
+        }
+        return data;
+    }
 }

Galanthus/SdfToc.cs

@@ -2,9 +2,11 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
+using System.IO;
 using Galanthus.Structs;
 using Galanthus.Utils;
 using StreamUtils;
+using File = Galanthus.Structs.File;
 
 namespace Galanthus;
 
@@ -516,4 +518,117 @@ public void Dispose()
             header.Dispose();
         }
     }
+
+    public unsafe Block<Byte> GetFileBytes(File fileEntry, string dataDir)
+    {
+        int outBufferSize = 0;
+        string sdfPath = null;
+
+        //get final file size
+        foreach (DataSlice dataSlice in fileEntry.DataSlices)
+        {
+            if (fileEntry.DdsIndex != -1)
+            {
+                outBufferSize += m_ddsHeaders[fileEntry.DdsIndex].Size;
+            }
+
+            if (!TryGetDataFile(dataSlice, out string? sdfName))
+            {
+                Console.WriteLine($"Wrong index {dataSlice.Index}");
+                continue;
+            }
+
+            sdfPath = Path.Combine(dataDir, sdfName);
+            if (System.IO.File.Exists(sdfPath))
+            {
+                outBufferSize += (int)dataSlice.DecompressedSize;
+            }
+
+        }
+        Block<Byte> outBuffer = new(outBufferSize);
+
+
+        //add dds header
+        if (fileEntry.DdsIndex != -1)
+        {
+            m_ddsHeaders[fileEntry.DdsIndex].CopyTo(outBuffer);
+            outBuffer.Shift(m_ddsHeaders[fileEntry.DdsIndex].Size);
+        }
+
+        //read slices 
+        foreach (DataSlice dataSlice in fileEntry.DataSlices)
+        {
+            if (!TryGetDataFile(dataSlice, out string? sdfName))
+            {
+                Console.WriteLine($"Wrong index {dataSlice.Index}");
+                continue;
+            }
+
+            sdfPath = Path.Combine(dataDir, sdfName);
+            if (System.IO.File.Exists(sdfPath))
+            {
+                using (DataStream stream = BlockStream.FromFile(sdfPath, dataSlice.Offset, (int)dataSlice.CompressedSize))
+                {
+                    //read slice
+                    Block<Byte> compressedBuffer = new((int)dataSlice.CompressedSize);
+                    stream.ReadExactly(compressedBuffer);
+
+                    //decrypt slice
+                    if (dataSlice.IsEncrypted)
+                    {
+                        if (m_header.Version >= 0x29 && compressedBuffer.Size >= 8)
+                        {
+                            // first they use XTEA encryption, then they use des encryption
+                            XTEA((uint*)compressedBuffer.Ptr, 32);
+
+                            // DES-PCBC
+                            // Problem is c# doesnt have native support for it
+                            if (Crypto.DecryptDes((nuint)compressedBuffer.Ptr, (compressedBuffer.Size >> 3) << 3, (nuint)compressedBuffer.Ptr, (nuint)KeyManager.Key.Ptr,
+                                    (nuint)KeyManager.Iv.Ptr) != 0)
+                            {
+                                return null;
+                            }
+                        }
+                        else if (compressedBuffer.Size >= 0x100)
+                        {
+                            // AES-192-OFB
+                            // Problem is c# doesnt have native support for it
+                            if (Crypto.DecryptAes((nuint)compressedBuffer.Ptr, 0x100, (nuint)compressedBuffer.Ptr, (nuint)KeyManager.Key.Ptr,
+                                    (nuint)KeyManager.Iv.Ptr) != 0)
+                            {
+                                return null;
+                            }
+                        }
+                    }
+
+                    //decompress slice
+                    if (dataSlice.IsCompressed)
+                    {
+                        if (!dataSlice.IsOodle)
+                        {
+                            ZStd.Decompress(compressedBuffer, ref outBuffer);
+                        }
+                        else
+                        {
+                            Console.WriteLine("Oodle slice!");
+                        }
+                    }
+                    else
+                    {
+                        compressedBuffer.CopyTo(outBuffer);
+                    }
+
+                    outBuffer.Shift((int)dataSlice.DecompressedSize);
+                    compressedBuffer.Dispose();
+                }
+            }
+            else
+            {
+                Console.WriteLine($"{sdfName} does not exist, skipping slice.");
+            }
+        }
+
+        outBuffer.ResetShift();
+        return outBuffer;
+    }
 }

GalanthusCli/Program.cs

@@ -1,4 +1,4 @@
-using System;
+using System;
 using System.CommandLine;
 using System.IO;
 using Galanthus;