FTPProvider.cs

	#region FTPFileExchange
	[System.Net.WebPermission(System.Security.Permissions.SecurityAction.Assert, Unrestricted = true)]
	public class FTPFileExchange : BaseFileExchange, IFileExchange
	{
		public String Name { get { return Messages.ExchangeFTP; } }
		public String Code { get { return Codes.ExchangeFTPCode; } }

		public FTPFileExchange(String login, String password)
			: base(login, password)
		{	}

		private FtpWebRequest GetFTPRequest(String path, String method, Boolean isFolder)
		{
			// Create FtpWebRequest object from the Uri provided
			FtpWebRequest request = (FtpWebRequest)FtpWebRequest.Create(GetFileUri(path, isFolder));

			if (_creds != null) request.Credentials = _creds;
			request.KeepAlive = false;
			request.UseBinary = true;
			
			// Specify the command to be executed.
			request.Method = method;

			return request;
		}
		private Uri GetFileUri(String path, Boolean isFolder)
		{
			StringBuilder sb = new StringBuilder(path);
			sb = sb.Replace("\\", "/");
			if (!path.StartsWithCollation("ftp")) sb = sb.Insert(0, "ftp://");
			if (isFolder && !path.EndsWithCollation("/")) sb = sb.Append("/");
			return new Uri(sb.ToString());
		}

		public override ExternalFileInfo GetInfo(String path)
		{
			ExternalFileInfo result = new ExternalFileInfo(System.IO.Path.GetFileName(path));
			result.FullName = path;
			result.Date = GetTimeStamp(result.FullName);
			return result;
		}
		public override IEnumerable<ExternalFileInfo> ListFiles(String path)
		{
			List<ExternalFileInfo> files = new List<ExternalFileInfo>();

			FtpWebRequest request = GetFTPRequest(path, WebRequestMethods.Ftp.ListDirectoryDetails, true);
			using (WebResponse response = request.GetResponse())
			{
				String line = null;
				using (StreamReader reader = new StreamReader(response.GetResponseStream()))
				{
					while ((line = reader.ReadLine()) != null)
					{
						ExternalFileInfo result = RegExpHelper.ParseFtpLine(line);
						if (result == null) continue;

						result.FullName = new Uri(path.EndsWith("/") ? new Uri(path) : new Uri(path + "/"), result.Name).ToString();
						result.Date = GetTimeStamp(result.FullName);
						files.Add(result);
					}
				}
			}

			return files;
		}
		public override Stream UploadStream(String path)
		{
			FtpWebRequest request = GetFTPRequest(path, WebRequestMethods.Ftp.UploadFile, false);

			Stream stream = request.GetRequestStream();
			return stream;
		}
		public override Stream DownloadStream(String path)
		{
			FtpWebRequest request = GetFTPRequest(path, WebRequestMethods.Ftp.DownloadFile, false);
			FtpWebResponse response = (FtpWebResponse)request.GetResponse();
			Stream stream = response.GetResponseStream();
			return stream;
		}

		private DateTime GetTimeStamp(String path)
		{
			FtpWebRequest request = GetFTPRequest(path, WebRequestMethods.Ftp.GetDateTimestamp, false);
			using (FtpWebResponse response = (FtpWebResponse)request.GetResponse())
			{
				string dateString = response.StatusDescription.Substring(4,14);
				return DateTime.ParseExact(dateString, "yyyyMMddHHmmss", System.Globalization.CultureInfo.InvariantCulture.DateTimeFormat);
			}
		}
	}
	#endregion