using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.IO;
using System.IO.Compression;

namespace Sleis.Utility
{
    public class CompressionUtility
    {
        // Use this method is used to read all bytes from a stream.
        public static int ReadAllBytesFromStream(Stream stream, byte[] buffer)
        {
            int offset = 0;
            int totalCount = 0;
            while (true)
            {
                int bytesRead = stream.Read(buffer, offset, 1024);
                if (bytesRead == 0)
                {
                    break;
                }
                offset += bytesRead;
                totalCount += bytesRead;
            }
            return totalCount;
        }

        public static byte[] Compress(byte[] content)
        {
           // byte[] result = null;
            using (MemoryStream ms = new MemoryStream())
            {
                using (GZipStream stream = new GZipStream(ms, CompressionMode.Compress, true))
                {
                    stream.Write(content, 0, content.Length);
                }
                ms.Position = 0;

               // ReadAllBytesFromStream(ms, result);
               return ms.ToArray();
            }
           // return result;

        }

        public static byte[] Decompress(byte[] content)
        {
            List<byte> result = new List<byte>();
            using (MemoryStream ms = new MemoryStream())
            {
                //write content to stream
                ms.Write(content, 0, content.Length);
                ms.Position = 0;
                using (GZipStream stream = new GZipStream(ms, CompressionMode.Decompress))
                {
                    int retVal = 0;
                    while (retVal >= 0)
                    {
                        retVal = stream.ReadByte();
                        if (retVal != -1)
                        {
                            result.Add((byte)retVal);
                        }
                    }
                    return result.ToArray();
                }

            }
           
        }

    }
}