From 8306be3f98aec123096da9e894725be88ae81a58 Mon Sep 17 00:00:00 2001
From: Torwent <Torwent@users.noreply.github.com>
Date: Mon, 27 Jul 2026 10:35:09 +0100
Subject: [PATCH] feat: add bzip2 decompression

---
 .../script/imports/simba.import_encoding.pas  |  2 +-
 Source/simba.compress.pas                     | 37 ++++++++++++++++++-
 2 files changed, 36 insertions(+), 3 deletions(-)

diff --git a/Source/script/imports/simba.import_encoding.pas b/Source/script/imports/simba.import_encoding.pas
index 6b487cca3..740400515 100644
--- a/Source/script/imports/simba.import_encoding.pas
+++ b/Source/script/imports/simba.import_encoding.pas
@@ -401,7 +401,7 @@ procedure ImportEncoding(Script: TSimbaScript);
     addGlobalFunc('function Hash32(Data: Pointer; Len: Int32; Seed: UInt32 = 0): UInt32; overload', @_LapeHash32);
     addGlobalFunc('function Hash32(S: String; Seed: UInt32 = 0): UInt32; overload', @_LapeHash32String);
 
-    addGlobalType('enum(ZLIB, SYNLZ, GZ, RLE)', 'ECompressAlgo');
+    addGlobalType('enum(ZLIB, SYNLZ, GZ, RLE, BZIP2)', 'ECompressAlgo');
 
     addGlobalFunc('procedure CompressData(Algo: ECompressAlgo; InData: Pointer; InSize: Int64; var OutData: Pointer; out OutSize: Int64; Truncate: Boolean = True);', @_LapeCompressData);
     addGlobalFunc('function CompressBytes(Algo: ECompressAlgo; Bytes: TByteArray): TByteArray', @_LapeCompressBytes);
diff --git a/Source/simba.compress.pas b/Source/simba.compress.pas
index deaa40aed..b74e43d8f 100644
--- a/Source/simba.compress.pas
+++ b/Source/simba.compress.pas
@@ -20,7 +20,8 @@ interface
     ZLIB,
     SYNLZ,
     GZ,
-    RLE
+    RLE,
+    BZIP2
   );
 {$POP}
 
@@ -42,7 +43,8 @@ implementation
   ZStream,
   castle_gz,
   mormot2_synlz,
-  mormot2_rle;
+  mormot2_rle,
+  bzip2stream;
 
 type
   TOutStream = class(TStream)
@@ -178,7 +180,9 @@ procedure CompressData(Algo: ESimbaCompressAlgo; InData: PByte; InSize: Int64; v
     ESimbaCompressAlgo.SYNLZ: CompressWithSynLZ();
     ESimbaCompressAlgo.GZ:    CompressWithGZ();
     ESimbaCompressAlgo.RLE:   CompressWithRle();
+    ESimbaCompressAlgo.BZIP2: SimbaException('BZip2 compression is not supported.');
   end;
+
   if Truncate then
     ReAllocMem(OutData, OutSize);
 end;
@@ -269,6 +273,34 @@ procedure DecompressData(Algo: ESimbaCompressAlgo; InData: PByte; InSize: Int64;
     end;
   end;
 
+  procedure DecompressWithBZip2;
+  var
+    InStream: TMemoryStream;
+    OutStream: TOutStream;
+    BZStream: TDecompressBzip2Stream;
+    Count: Integer;
+    Chunk: array[0..4095] of Byte;
+  begin
+    InStream := TMemoryStream.Create();
+    InStream.Write(InData^, InSize);
+    InStream.Position := 0;
+    OutStream := TOutStream.Create(OutData);
+    BZStream := TDecompressBzip2Stream.Create(InStream);
+    try
+      repeat
+        Count := BZStream.Read(Chunk[0], Length(Chunk));
+        if (Count > 0) then
+          OutStream.Write(Chunk[0], Count);
+      until (Count = 0);
+      OutSize := OutStream.Position;
+      OutData := OutStream.Data;
+    finally
+      InStream.Free();
+      OutStream.Free();
+      BZStream.Free();
+    end;
+  end;
+
 begin
   OutSize := 0;
   if (InSize < 0) or (InSize > High(Int32)) then
@@ -279,6 +311,7 @@ procedure DecompressData(Algo: ESimbaCompressAlgo; InData: PByte; InSize: Int64;
     ESimbaCompressAlgo.SYNLZ: DecompressWithSynLZ();
     ESimbaCompressAlgo.GZ:    DecompressWithGZ();
     ESimbaCompressAlgo.RLE:   DecompressWithRLE();
+    ESimbaCompressAlgo.BZIP2: DecompressWithBZip2();
   end;
   if Truncate then
     ReAllocMem(OutData, OutSize);