using System;
using K4os.Compression.LZ4;

namespace SongCore.Arcache
{
    // idx: [[len:2] [u8str:len] [offset:8] [compressedSize:8] [originalSize:8]] ...
    // dat: [block] ...

    public abstract class Lz4ArchiveBase
    {
        public static byte[] Compress(byte[] source)
        {
            var target = new byte[LZ4Codec.MaximumOutputSize(source.Length)];
            var len = LZ4Codec.Encode(source, target, LZ4Level.L12_MAX);
            var compressed = new byte[len];
            Buffer.BlockCopy(target, 0, compressed, 0, len);
            return compressed;
        }

        public static byte[] Decompress(byte[] source, int originalSize)
        {
            var decompressed = new byte[originalSize];
            LZ4Codec.Decode(source, decompressed);
            return decompressed;
        }

        public static byte[] CompressPickle(byte[] source)
        {
            return LZ4Pickler.Pickle(source,LZ4Level.L12_MAX);
        }

        public static byte[] DecompressPickle(byte[] source)
        {
            return LZ4Pickler.Unpickle(source);
        }

        protected internal string BlobFilePath;
        protected internal string IndexFilePath;

        protected internal Lz4ArchiveBase(string pathAndBaseName)
        {
            BlobFilePath = pathAndBaseName + ".lz4a";
            IndexFilePath = pathAndBaseName + ".lz4i";
        }
    }
}