using System;
using System.Configuration;
using System.Collections.Generic;
using System.Text;
using System.Web;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.Security;
using System.IO;
using System.IO.Compression;
using System.Xml;
using System.Diagnostics;
using System.Windows.Forms;
using System.Threading;
using System.Security.Cryptography;

namespace HH.WMS.Utils
{
    public partial class ZFiles
    {
        /// <summary>
        /// method for getting a files MD5 hash, say for
        /// a checksum operation
        /// </summary>
        /// <param name="file">the file we want the has from</param>
        /// <returns></returns>
        public static string GetHashMD5(Stream stream)
        {
            //MD5 hash provider for computing the hash of the file
            MD5CryptoServiceProvider md5 = new MD5CryptoServiceProvider();

            //calculate the files hash
            md5.ComputeHash(stream);

            //byte array of files hash
            byte[] hash = md5.Hash;

            //string builder to hold the results
            StringBuilder sb = new StringBuilder();

            //loop through each byte in the byte array
            foreach (byte b in hash)
            {
                //format each byte into the proper value and append
                //current value to return value
                sb.Append(string.Format("{0:X2}", b));
            }

            //return the MD5 hash of the file
            return sb.ToString();
        }

        public static string GetHashMD5(string file)
        {
            //open the file
             FileStream stream = new FileStream(file, FileMode.Open, FileAccess.Read, FileShare.Read, 8192);
            
             string hashMD5 =  GetHashMD5(stream);

            //close our stream
             stream.Close();

            return hashMD5;
           
        }
    }
}