From 345746d34d9f64aa41a87608626da2209fc69f56 Mon Sep 17 00:00:00 2001
From: Brian Fiete <bfiete@gmail.com>
Date: Sun, 14 Nov 2021 18:01:37 -0800
Subject: [PATCH] zlib interface

---
 BeefLibs/Beefy2D/src/utils/Compression.bf |  57 ++++++++++
 BeefySysLib/util/Compress.cpp             | 126 ++++++++++++++++++++++
 BeefySysLib/util/Compress.h               |  16 +++
 3 files changed, 199 insertions(+)
 create mode 100644 BeefLibs/Beefy2D/src/utils/Compression.bf
 create mode 100644 BeefySysLib/util/Compress.cpp
 create mode 100644 BeefySysLib/util/Compress.h

diff --git a/BeefLibs/Beefy2D/src/utils/Compression.bf b/BeefLibs/Beefy2D/src/utils/Compression.bf
new file mode 100644
index 00000000..a680b9ea
--- /dev/null
+++ b/BeefLibs/Beefy2D/src/utils/Compression.bf
@@ -0,0 +1,57 @@
+using System;
+using System.Collections;
+
+namespace utils
+{
+	class Compression
+	{
+		[CallingConvention(.Stdcall), CLink]
+		extern static Span<uint8> Compression_Compress(void* ptr, int size);
+
+		[CallingConvention(.Stdcall), CLink]
+		extern static Span<uint8> Compression_Decompress(void* ptr, int size);
+
+		[CallingConvention(.Stdcall), CLink]
+		extern static void Compression_Free(void* ptr);
+
+		public static Result<void> Compress(Span<uint8> inData, List<uint8> outData)
+		{
+			var outSpan = Compression_Compress(inData.Ptr, inData.Length);
+			if ((outSpan.Length == 0) && (inData.Length != 0))
+				return .Err;
+			outData.AddRange(outSpan);
+			Compression_Free(outSpan.Ptr);
+			return .Ok;
+		}
+
+		public static Result<void> Compress(Span<uint8> inData, String outData)
+		{
+			var outSpan = Compression_Compress(inData.Ptr, inData.Length);
+			if ((outSpan.Length == 0) && (inData.Length != 0))
+				return .Err;
+			outData.Insert(outData.Length, StringView((.)outSpan.Ptr, outSpan.Length));
+			Compression_Free(outSpan.Ptr);
+			return .Ok;
+		}
+
+		public static Result<void> Decompress(Span<uint8> inData, List<uint8> outData)
+		{
+			var outSpan = Compression_Decompress(inData.Ptr, inData.Length);
+			if ((outSpan.Length == 0) && (inData.Length != 0))
+				return .Err;
+			outData.AddRange(outSpan);
+			Compression_Free(outSpan.Ptr);
+			return .Ok;
+		}
+
+		public static Result<void> Decompress(Span<uint8> inData, String outData)
+		{
+			var outSpan = Compression_Decompress(inData.Ptr, inData.Length);
+			if ((outSpan.Length == 0) && (inData.Length != 0))
+				return .Err;
+			outData.Insert(outData.Length, StringView((.)outSpan.Ptr, outSpan.Length));
+			Compression_Free(outSpan.Ptr);
+			return .Ok;
+		}
+	}
+}
diff --git a/BeefySysLib/util/Compress.cpp b/BeefySysLib/util/Compress.cpp
new file mode 100644
index 00000000..7040a226
--- /dev/null
+++ b/BeefySysLib/util/Compress.cpp
@@ -0,0 +1,126 @@
+#include "Compress.h"
+#include "third_party/zlib/zlib.h"
+#include "TLSingleton.h"
+
+#pragma warning(disable:4190)
+
+USING_NS_BF;
+
+bool Compression::Compress(Span<uint8> inData, Array<uint8>& outData)
+{
+	outData.Reserve(128);
+
+	z_stream zs;
+	zs.zalloc = Z_NULL;
+	zs.zfree = Z_NULL;
+	zs.opaque = Z_NULL;	
+	zs.avail_in = (int)inData.mSize;
+	zs.next_in = inData.mVals;
+	zs.next_out = outData.mVals;
+	zs.avail_out = outData.mAllocSize;
+	
+	deflateInit(&zs, Z_BEST_COMPRESSION);
+
+	bool isDone = false;
+	bool hadError = false;
+
+	while (true)
+	{
+		bool isDone = zs.avail_in == 0;
+		
+		int err = deflate(&zs, isDone ? Z_FINISH : Z_NO_FLUSH);
+		outData.mSize = (int)(zs.next_out - outData.mVals);
+
+		if (err < 0)
+		{
+			hadError = true;
+			break;
+		}
+
+		if ((isDone) && (err == Z_STREAM_END))
+			break;
+
+		if (zs.avail_out == 0)
+		{
+			outData.Reserve((int)outData.mAllocSize + (int)outData.mAllocSize / 2 + 1);
+			zs.next_out = outData.mVals + outData.mSize;
+			zs.avail_out = outData.mAllocSize - outData.mSize;
+		}		
+	}
+	
+	deflateEnd(&zs);	
+	return !hadError;
+}
+
+bool Compression::Decompress(Span<uint8> inData, Array<uint8>& outData)
+{
+	outData.Reserve(128);
+
+	z_stream zs;
+	zs.zalloc = Z_NULL;
+	zs.zfree = Z_NULL;
+	zs.opaque = Z_NULL;
+	zs.avail_in = (int)inData.mSize;
+	zs.next_in = inData.mVals;
+	zs.next_out = outData.mVals;
+	zs.avail_out = outData.mAllocSize;
+
+	inflateInit(&zs, Z_BEST_COMPRESSION);
+
+	bool isDone = false;
+	bool hadError = false;
+
+	while (true)
+	{
+		bool isDone = zs.avail_in == 0;
+
+		int err = inflate(&zs, isDone ? Z_FINISH : Z_NO_FLUSH);
+		outData.mSize = (int)(zs.next_out - outData.mVals);
+
+		if (err < 0)
+		{
+			hadError = true;
+			break;
+		}
+
+		if ((isDone) && (err == Z_STREAM_END))
+			break;
+		
+		if (zs.avail_out == 0)
+		{
+			outData.Reserve((int)outData.mAllocSize + (int)outData.mAllocSize / 2 + 1);
+			zs.next_out = outData.mVals + outData.mSize;
+			zs.avail_out = outData.mAllocSize - outData.mSize;
+		}
+	}
+
+	inflateEnd(&zs);
+	return !hadError;
+}
+
+//////////////////////////////////////////////////////////////////////////
+
+BF_EXPORT Span<uint8> BF_CALLTYPE Compression_Compress(void* ptr, int size)
+{
+	Array<uint8> outData;
+	if (!Compression::Compress(Span<uint8>((uint8*)ptr, size), outData))	
+		return Span<uint8>();	
+	uint8* outPtr = outData.mVals;
+	outData.mVals = NULL;
+	return Span<uint8>(outPtr, outData.mSize);
+}
+
+BF_EXPORT Span<uint8> BF_CALLTYPE Compression_Decompress(void* ptr, int size)
+{
+	Array<uint8> outData;
+	if (!Compression::Decompress(Span<uint8>((uint8*)ptr, size), outData))
+		return Span<uint8>();
+	uint8* outPtr = outData.mVals;
+	outData.mVals = NULL;
+	return Span<uint8>(outPtr, outData.mSize);
+}
+
+BF_EXPORT void BF_CALLTYPE Compression_Free(void* ptr)
+{
+	delete ptr;
+}
diff --git a/BeefySysLib/util/Compress.h b/BeefySysLib/util/Compress.h
new file mode 100644
index 00000000..06785abb
--- /dev/null
+++ b/BeefySysLib/util/Compress.h
@@ -0,0 +1,16 @@
+#pragma once
+
+#include "../Common.h"
+#include "Array.h"
+#include "Span.h"
+
+NS_BF_BEGIN;
+
+class Compression
+{
+public:
+	static bool Compress(Span<uint8> inData, Array<uint8>& outData);
+	static bool Decompress(Span<uint8> inData, Array<uint8>& outData);
+};
+
+NS_BF_END;