using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.IO;

namespace Btg.Zip
{
    /// <summary>
    /// Windows File compression
    /// The SourceDirectory can be a directory or a file.  Look at CopyHere in help for the Flags.
    /// This uses the Windows compression mechanism.  Reference Microsoft Shell Controls and Automation on the Com tab.
    /// </summary>
    public class WindowsZipCompression
    {

        #region ZipFile
        /// <summary>
        /// zip up only the file name
        /// compress a file with L-Z algorithim
        /// </summary>
        /// <param name="Input">file name in</param>
        /// <param name="Filename">Out file name</param>
        public void ZipFile(string Input, string Filename)
        {
            Shell32.Shell Shell = new Shell32.Shell();
        
            //Create our Zip File
            CreateZipFile(Filename);

            //Copy the file or folder to it
            Shell.NameSpace(Filename).CopyHere(Input,0);
          
            //If you can write the code to wait for the code to finish, please let me know
            System.Threading.Thread.Sleep(2000);
            {

            }
        }
        /// <summary>
        /// 
        /// pk zip header  "PK" + (char)5 + (char)6;
        /// </summary>
        /// <param name="filename"></param>
        private void CreateZipFile(string filename)
        {
            //Create the header of the Zip File 
            System.Text.ASCIIEncoding Encoder = new System.Text.ASCIIEncoding();
            string sHeader = "PK" + (char)5 + (char)6;
            sHeader = sHeader.PadRight(22, (char)0);
            SaveFile(filename, sHeader);            
        }
        /// <summary>
        /// actually saves the zip file
        /// </summary>
        /// <param name="filename"></param>
        /// <param name="sHeader"></param>
        private void SaveFile(string filename, string sHeader)
        {
            //Convert to byte array
            byte[] baHeader = System.Text.Encoding.ASCII.GetBytes(sHeader);
            //Save File - Make sure your file ends with .zip!
            FileStream fs = File.Create(filename);
            fs.Write(baHeader, 0, baHeader.Length);
            fs.Flush();
            fs.Close();
            fs = null;
        }

        #endregion ZipFile


        #region ZipDirectory
        /// <summary>
        /// zip up a whole directory
        /// pk zip header "PK\x05\x06"
        /// Example of InputDirectory - "C:\\Program Files"
        /// </summary>
        /// <param name="InputDirectory"></param>
        /// <param name="Filename"></param>
        public void ZipDirectory(string InputDirectory, string Filename)
        {
            string ZipFile = Filename;
            System.IO.File.WriteAllText(ZipFile, "PK\x05\x06" + new String('\0', 18));
            CopyDirectory(InputDirectory, ZipFile, 0);
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="SourceDirectory"></param>
        /// <param name="DestinationDirectory"></param>
        /// <param name="Flags"></param>
        private void CopyDirectory(string SourceDirectory, string DestinationDirectory, int Flags)
        {
            Shell32.Shell Sh = new Shell32.Shell();
            Shell32.Folder SD = Sh.NameSpace(SourceDirectory);
            Shell32.Folder DD = Sh.NameSpace(DestinationDirectory);
            DD.CopyHere(SD, Flags);
            System.Runtime.InteropServices.Marshal.FinalReleaseComObject(Sh);
        }

        #endregion ZipDirectory

    }
}