/***
    Copyright (C) 2021 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: CompressInfo.hpp
    Date: 2021-7-14
    Author: Reece
***/
#pragma once

namespace Aurora::Compression
{
    using CompressionOptions_t = AuList<AuPair<int, int>>;

    struct CompressInfo
    {
        AU_COPY_MOVE_DEF(CompressInfo);

        ECompressionType type;
        
        /**
         * @brief 
         * 
         * ZSTD: -5 <= level <= 22
         *      recommended: ZSTD_CLEVEL_DEFAULT 
         * LZMA: 0 <= level <= 9
         * LZ4 : N/A
         * Deflate: 0 <= x >= 9,
         *      recommended: 6
         * Zip: 0 <= x <= 9, 
         *      recommended: 6
         * GZip: 0 <= x <= 9, 
         *      recommended: 6
         * BZIP: 0 <= x <= 9
         * 
        */
        AuInt8 uCompressionLevel { 6 };

        /**
         * @brief LZMA: 5 <= fb <= 273, default = 32
        */
        AuUInt32 uFbWordSize { 32 };

        /**
         *  LZMA only
         *  (1 << 12) <= dictSize <= (1 << 27) for 32-bit version
         *  (1 << 12) <= dictSize <= (3 << 29) for 64-bit version
         *  default = (1 << 24) 
        */
        AuUInt32 uDictSize { };

        /**
         * @brief 64KiB is a recommended "small" block size
         * todo: lzma respects this
        */
        AuUInt16 uBlockSize {};

        /**
         * @brief DEFLATE related variabl
         * 
         * Deflate: 0 <= x <= 15,
         *      recommended: 15
         * Zip: 0 <= x <= 15,
         *      recommended: 15
         * GZip: 0 <= x <= 15,
         *      recommended: 15
         * Brotli: 16 <= x <= 24 
         *      recommended: 
        */
        AuOptionalEx<AuUInt8> uOptWindowBits { };

        /**
         * brotli: 0 <= x <= 11,
         * zstd: 0 <= x <= 9,
        */
        AuOptionalEx<AuUInt8> uOptQuality { 7 };

        /**
         * @brief Internal output buffer size.
        */
        AuUInt32 uInternalStreamSize { 512 * 1024 };

        AuUInt8 uThreads { 1 };

        bool bLZ4AutoFlush {false};

        CompressionOptions_t options;

        bool bErrorCheck { true };

        inline CompressInfo(ECompressionType alg) : type(alg)
        {

        }

        inline CompressInfo(ECompressionType alg, AuUInt32 bufferSize) : type(alg), uInternalStreamSize(bufferSize)
        {

        }
    };
    
    struct DecompressInfo
    {
        AU_COPY_MOVE(DecompressInfo);

        /**
         * @brief algorithm
        */
        ECompressionType alg { ECompressionType::eDeflate };

        /**
         * @brief Internal output buffer size.
        */
        AuUInt32 uInternalStreamSize { 512 * 1024 };
        
        /**
         * @brief Flag for headerless decompression streams
        */
        AuOptionalEx<AuInt8> uOptWindowBits { };

        AuUInt8 uThreads { 1 };

        CompressionOptions_t options;

        bool bErrorCheck { true };

        inline DecompressInfo(ECompressionType alg) : alg(alg)
        {

        }

        inline DecompressInfo(ECompressionType alg, AuUInt32 bufferSize) : alg(alg), uInternalStreamSize(bufferSize)
        {

        }
    };
}