using System;
using System.Collections.Generic;
using System.IO;
using System.IO.Compression;
using System.Linq;
using System.Text;
using Ionic.BZip2;

    public static class Compress
    {
        public static System.Text.Encoding Coding = System.Text.Encoding.UTF8;
        public static string CompressGZip(string text)
        {
            byte[] buffer = Encoding.UTF8.GetBytes(text);
            var memoryStream = new MemoryStream();
            using (var gZipStream = new GZipStream(memoryStream, CompressionMode.Compress, true))
            {
                gZipStream.Write(buffer, 0, buffer.Length);
            }

            memoryStream.Position = 0;

            var compressedData = new byte[memoryStream.Length];
            memoryStream.Read(compressedData, 0, compressedData.Length);

            var gZipBuffer = new byte[compressedData.Length + 4];
            Buffer.BlockCopy(compressedData, 0, gZipBuffer, 4, compressedData.Length);
            Buffer.BlockCopy(BitConverter.GetBytes(buffer.Length), 0, gZipBuffer, 0, 4);
            return Convert.ToBase64String(gZipBuffer);
        }

        /// <summary>
        /// Decompresses the string.
        /// </summary>
        /// <param name="compressedText">The compressed text.</param>
        /// <returns></returns>
        public static string DecompressGZip(string compressedText)
        {
            byte[] gZipBuffer = Convert.FromBase64String(compressedText);
            using (var memoryStream = new MemoryStream())
            {
                int dataLength = BitConverter.ToInt32(gZipBuffer, 0);
                memoryStream.Write(gZipBuffer, 4, gZipBuffer.Length - 4);

                var buffer = new byte[dataLength];

                memoryStream.Position = 0;
                using (var gZipStream = new GZipStream(memoryStream, CompressionMode.Decompress))
                {
                    gZipStream.Read(buffer, 0, buffer.Length);
                }

                return Coding.GetString(buffer);
            }
        }
        public static string DecompressBZip(String compressedText)
        {
            if (String.IsNullOrEmpty(compressedText)) return String.Empty;
            
            byte[] bytes = System.Text.Encoding.UTF8.GetBytes(compressedText);
            compressedText = DecompressBZip(bytes);
            Encoding srcEncodingFormat = Coding;
            Encoding dstEncodingFormat = Coding;
            byte[] originalByteString = srcEncodingFormat.GetBytes(compressedText);
            byte[] convertedByteString = Encoding.Convert(srcEncodingFormat, dstEncodingFormat, originalByteString);
            compressedText = dstEncodingFormat.GetString(convertedByteString);
            return compressedText;
        }
        static string DecompressBZip(byte[] compressedbytes)
        {
            String result;
            MemoryStream m_msBZip2 = new MemoryStream(compressedbytes);
            using (BinaryReader reader = new BinaryReader(m_msBZip2, Coding))
            {
                Int32 size = reader.ReadInt32();

                using (var m_isBZip2 = new BZip2InputStream(m_msBZip2))
                {
                    byte[] bytesUncompressed = new byte[size];
                    m_isBZip2.Read(bytesUncompressed, 0, bytesUncompressed.Length);
                    m_isBZip2.Close();
                    m_msBZip2.Close();

                    result = Coding.GetString(bytesUncompressed, 0, bytesUncompressed.Length);

                    reader.Close();
                }
            }
            return result;
        }
        public static byte[] CompressBZip(string sBuffer)
        {
            byte[] result;
            using (MemoryStream m_msBZip2 = new MemoryStream())
            {
                Int32 size = sBuffer.Length;

                using (BinaryWriter writer = new BinaryWriter(m_msBZip2, Coding))//, System.Text.Encoding.ASCII))
                {
                    writer.Write(size);

                    using (BZip2OutputStream m_osBZip2 = new BZip2OutputStream(m_msBZip2))
                    {
                        m_osBZip2.Write(Coding.GetBytes(sBuffer), 0, sBuffer.Length);
                        m_osBZip2.Close();
                    }

                    writer.Close();
                    result = m_msBZip2.ToArray();

                    m_msBZip2.Close();
                }
            }
            return result;

        }
    }