/// Version 1.0.0
/// Last modified 24.5.2014
///
/// Copyright (C) 2014 Veli-Mikko Puupponen
///
/// Halyri-system is a prototype emergency call system. Its purpose is to
/// demonstrate the use of the advanced capabilities available in the current
/// generation smartphones in facilitating the emergency service dispatcher's
/// capability to determine the nature of the emergency and to dispatch help.
///
/// For more information, see the README file of this package.
///
/// The MIT License (MIT)
///
/// Permission is hereby granted, free of charge, to any person obtaining a copy
/// of this software and associated documentation files (the "Software"), to
/// deal in the Software without restriction, including without limitation the
/// rights to use, copy, modify, merge, publish, distribute, sublicense,
/// and/or sell copies of the Software, and to permit persons to whom the
/// Software is furnished to do so, subject to the following conditions:
///
/// The above copyright notice and this permission notice shall be included in
/// all copies or substantial portions of the Software.
///
/// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
/// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
/// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
/// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
/// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
/// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
/// IN THE SOFTWARE.
///

using System.IO;
using System.IO.Compression;

namespace Hake_WPF.Conversion {
    /// <author>Veli-Mikko Puupponen</author>
    /// <summary>
    /// The class for static compression methods. It contains methods to compress and decompress data.
    /// 
    /// NOTICE: IO.Compression-library will not work, if the solution has Active Config set to any CPU. For
    /// phone, this should be ARM and for emulator, x86.
    /// </summary>
    class CompressionHelper
    {
        /// <summary>
        /// The function compresses the provided byte array using the GZip algorithm provided by
        /// System.IO.Compression library.
        /// </summary>
        /// <param name="sourceData">The data to be compressed.</param>
        /// <param name="useOptimalCompression">True, if using optimal compression method, otherwise using fastest.</param>
        /// <returns>The input data compressed with GZip.</returns>
        public static byte[] CompressGZip(byte[] sourceData, bool useOptimalCompression)
        {
            byte[] compressedData;
            CompressionLevel level = CompressionLevel.Fastest;
            if (useOptimalCompression)
                level = CompressionLevel.Optimal;
            using (MemoryStream inputStream = new MemoryStream(sourceData))
            {
                using (MemoryStream compressedStream = new MemoryStream())
                {
                    using (GZipStream compressionStream = new GZipStream(compressedStream, level))
                    {
                        inputStream.CopyTo(compressionStream);
                    }
                    compressedData = compressedStream.ToArray();
                }
            }
            return compressedData;
        }

        /// <summary>
        /// The function decompresses the provided byte array using the GZip algorithm provided by
        /// System.IO.Compression library.
        /// </summary>
        /// <param name="sourceData">The data to be decompressed.</param>
        /// <returns>The input data decompressed with GZip.</returns>
        public static byte[] DecompressGZip(byte[] sourceData)
        {
            byte[] decompressedData;
            using (MemoryStream inputStream = new MemoryStream(sourceData))
            {
                using (MemoryStream decompressedStream = new MemoryStream())
                {
                    using (GZipStream decompressionStream = new GZipStream(inputStream, CompressionMode.Decompress))
                    {
                        decompressionStream.CopyTo(decompressedStream);
                    }
                    decompressedData = decompressedStream.ToArray();
                }
            }
            return decompressedData;
        }

    }
}