using System;
using System.Collections.Generic;
using System.Text;

namespace UpdateServiceLibrary.Helper
{
    public class DownLoadFileHelper
    {
        public long TotalSize = 0;
        public long DownloadedSize = 0;
        public int buffSize = 1024;
        public Action<long, long> DownloadStatus;

        public ResultModel<Exception> DownloadFile(string URL, string filename)
        {
            ResultModel<Exception> result = new ResultModel<Exception> { IsSuccess= true };
            try
            {
                System.Net.HttpWebRequest Myrq = (System.Net.HttpWebRequest)System.Net.HttpWebRequest.Create(URL);
                System.Net.HttpWebResponse myrp = (System.Net.HttpWebResponse)Myrq.GetResponse();
                TotalSize = myrp.ContentLength;

                if (DownloadStatus != null)
                    DownloadStatus(TotalSize, DownloadedSize);

                System.IO.Stream st = myrp.GetResponseStream();
                System.IO.Stream so = new System.IO.FileStream(filename, System.IO.FileMode.Create);
                byte[] by = new byte[buffSize];
                int osize = st.Read(by, 0, (int)by.Length);
                while (osize > 0)
                {
                    DownloadedSize += osize;

                    if (DownloadStatus != null)
                        DownloadStatus(TotalSize, DownloadedSize);

                    so.Write(by, 0, osize);
                    osize = st.Read(by, 0, (int)by.Length);
                }
                so.Close();
                st.Close();
                myrp.Close();
                Myrq.Abort();
            }
            catch (System.Exception e)
            {
                result.IsSuccess = false;
                result.Data = e;
            }
            return result;
        }
    }
}