context: #region Disclaimer / License
  // Copyright (C) 2015, The Duplicati Team
  // http://www.duplicati.com, info@duplicati.com
  // 
  // This library is free software; you can redistribute it and/or
  // modify it under the terms of the GNU Lesser General Public
  // License as published by the Free Software Foundation; either
  // version 2.1 of the License, or (at your option) any later version.
  // 
  // This library is distributed in the hope that it will be useful,
  // but WITHOUT ANY WARRANTY; without even the implied warranty of
  // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  // Lesser General Public License for more details.
  // 
  // You should have received a copy of the GNU Lesser General Public
  // License along with this library; if not, write to the Free Software
  // Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  // 
  #endregion
  using System;
  using System.Collections.Generic;
  using System.Text;
  using Duplicati.Library.Interface;
  
  namespace Duplicati.Library.Backend
  {
      public class File : IBackend, IStreamingBackend, IQuotaEnabledBackend, IRenameEnabledBackend
      {
          private const string OPTION_DESTINATION_MARKER = "alternate-destination-marker";
          private const string OPTION_ALTERNATE_PATHS = "alternate-target-paths";
          private const string OPTION_MOVE_FILE = "use-move-for-put";
          private const string OPTION_FORCE_REAUTH = "force-smb-authentication";
  
          private string m_path;
          private string m_username;
          private string m_password;
          private bool m_moveFile;
          private bool m_hasAutenticated;
          private bool m_forceReauth;
  
          private readonly byte[] m_copybuffer = new byte[Duplicati.Library.Utility.Utility.DEFAULT_BUFFER_SIZE];
  
  
          public File()
          {
          }
  
          public File(string url, Dictionary<string, string> options)
          {
              var uri = new Utility.Uri(url);
              m_path = uri.HostAndPath;
              
              if (options.ContainsKey("auth-username"))
                  m_username = options["auth-username"];
              if (options.ContainsKey("auth-password"))
                  m_password = options["auth-password"];
              if (!string.IsNullOrEmpty(uri.Username))
                  m_username = uri.Username;
              if (!string.IsNullOrEmpty(uri.Password))
                  m_password = uri.Password;
              
              if (!System.IO.Path.IsPathRooted(m_path))
                  m_path = System.IO.Path.GetFullPath(m_path);
  
              if (options.ContainsKey(OPTION_ALTERNATE_PATHS))
              {
                  List<string> paths = new List<string>();
                  paths.Add(m_path);
                  paths.AddRange(options[OPTION_ALTERNATE_PATHS].Split(new string[] { System.IO.Path.PathSeparator.ToString() }, StringSplitOptions.RemoveEmptyEntries));
  
                  //On windows we expand the drive letter * to all drives
                  if (!Utility.Utility.IsClientLinux)
                  {
                      System.IO.DriveInfo[] drives = System.IO.DriveInfo.GetDrives();
                      
                      for (int i = 0; i < paths.Count; i++)
                      {
                          if (paths[i].StartsWith("*:"))
                          {
                              string rpl_path = paths[i].Substring(1);
                              paths.RemoveAt(i);
                              i--;
                              foreach (System.IO.DriveInfo di in drives)
                                  paths.Insert(++i, di.Name[0] + rpl_path);
                          }
                      }
                  }
  
                  string markerfile = null;
  
                  //If there is a marker file, we do not allow the primary target path
                  // to be accepted, unless it contains the marker file
                  if (options.ContainsKey(OPTION_DESTINATION_MARKER))
                  {
                      markerfile = options[OPTION_DESTINATION_MARKER];
                      m_path = null;
                  }
  
                  foreach (string p in paths)
                  {
                      try
                      {
                          if (System.IO.Directory.Exists(p) && (markerfile == null || System.IO.File.Exists(System.IO.Path.Combine(p, markerfile))))
                          {
                              m_path = p;
                              break;
                          }
                      }
                      catch
                      {
                      }
                  }
  
                  if (m_path == null)
                      throw new UserInformationException(Strings.FileBackend.NoDestinationWithMarkerFileError(markerfile, paths.ToArray()));
              }
  
              m_moveFile = Utility.Utility.ParseBoolOption(options, OPTION_MOVE_FILE);
              m_forceReauth = Utility.Utility.ParseBoolOption(options, OPTION_FORCE_REAUTH);
              m_hasAutenticated = false;
          }
  
          private void PreAuthenticate()
          {
              try
              {
                  if (!string.IsNullOrEmpty(m_username) && m_password != null)
                  {
                      if (!m_hasAutenticated)
                      {
                          Win32.PreAuthenticate(m_path, m_username, m_password, m_forceReauth);
                          m_hasAutenticated = true;
                      }
                  }
              }
              catch
              { }
          }
  
          private string GetRemoteName(string remotename)
          {
              PreAuthenticate();
  
              if (!System.IO.Directory.Exists(m_path))
                  throw new FolderMissingException(Strings.FileBackend.FolderMissingError(m_path));
  
              return System.IO.Path.Combine(m_path, remotename);
          }
  
          #region IBackendInterface Members
  
          public string DisplayName
          {
              get { return Strings.FileBackend.DisplayName; }
          }
  
          public string ProtocolKey
          {
              get { return "file"; }
          }
  
          public bool SupportsStreaming
          {
              get { return true; }
          }
  
          public List<IFileEntry> List()
          {
              List<IFileEntry> ls = new List<IFileEntry>();
  
              PreAuthenticate();
  
              if (!System.IO.Directory.Exists(m_path))
                  throw new FolderMissingException(Strings.FileBackend.FolderMissingError(m_path));
  
              foreach (string s in System.IO.Directory.GetFiles(m_path))
              {
                  System.IO.FileInfo fi = new System.IO.FileInfo(s);
                  ls.Add(new FileEntry(fi.Name, fi.Length, fi.LastAccessTime, fi.LastWriteTime));
              }
  
              foreach (string s in System.IO.Directory.GetDirectories(m_path))
              {
                  System.IO.DirectoryInfo di = new System.IO.DirectoryInfo(s);
                  FileEntry fe = new FileEntry(di.Name, 0, di.LastAccessTime, di.LastWriteTime);
                  fe.IsFolder = true;
                  ls.Add(fe);
              }
  
              return ls;
          }
  
  #if DEBUG_RETRY
          private static Random random = new Random();
          public void Put(string remotename, System.IO.Stream stream)
          {
              using(System.IO.FileStream writestream = System.IO.File.Open(GetRemoteName(remotename), System.IO.FileMode.Create, System.IO.FileAccess.Write, System.IO.FileShare.None))
              {
                  if (random.NextDouble() > 0.6666)
                      throw new Exception("Random upload failure");
                  Utility.Utility.CopyStream(stream, writestream);
              }
          }
  #else
          public void Put(string remotename, System.IO.Stream stream)
          {
              using(System.IO.FileStream writestream = System.IO.File.Open(GetRemoteName(remotename), System.IO.FileMode.Create, System.IO.FileAccess.Write, System.IO.FileShare.None))
                  Utility.Utility.CopyStream(stream, writestream, true, m_copybuffer);
          }
  #endif
  
          public void Get(string remotename, System.IO.Stream stream)
          {
              using (System.IO.FileStream readstream = System.IO.File.Open(GetRemoteName(remotename), System.IO.FileMode.Open, System.IO.FileAccess.Read, System.IO.FileShare.Read))
                  Utility.Utility.CopyStream(readstream, stream, true, m_copybuffer);
          }
  
          public void Put(string remotename, string filename)
          {
              string path = GetRemoteName(remotename);
              if (m_moveFile)
              {
                  if (System.IO.File.Exists(path))
                      System.IO.File.Delete(path);
                  
                  System.IO.File.Move(filename, path);
              }
              else
                  System.IO.File.Copy(filename, path, true);
          }
  
          public void Get(string remotename, string filename)
          {
              System.IO.File.Copy(GetRemoteName(remotename), filename, true);
          }
  
          public void Delete(string remotename)
          {
              System.IO.File.Delete(GetRemoteName(remotename));
          }
  
          public IList<ICommandLineArgument> SupportedCommands
          {
              get
              {
                  return new List<ICommandLineArgument>(new ICommandLineArgument[] {
                      new CommandLineArgument("auth-password", CommandLineArgument.ArgumentType.Password, Strings.FileBackend.DescriptionAuthPasswordShort, Strings.FileBackend.DescriptionAuthPasswordLong),
                      new CommandLineArgument("auth-username", CommandLineArgument.ArgumentType.String, Strings.FileBackend.DescriptionAuthUsernameShort, Strings.FileBackend.DescriptionAuthUsernameLong),
                      new CommandLineArgument(OPTION_DESTINATION_MARKER, CommandLineArgument.ArgumentType.String, Strings.FileBackend.AlternateDestinationMarkerShort, Strings.FileBackend.AlternateDestinationMarkerLong(OPTION_ALTERNATE_PATHS)),
                      new CommandLineArgument(OPTION_ALTERNATE_PATHS, CommandLineArgument.ArgumentType.Path, Strings.FileBackend.AlternateTargetPathsShort, Strings.FileBackend.AlternateTargetPathsLong(OPTION_DESTINATION_MARKER, System.IO.Path.PathSeparator)),
                      new CommandLineArgument(OPTION_MOVE_FILE, CommandLineArgument.ArgumentType.Boolean, Strings.FileBackend.UseMoveForPutShort, Strings.FileBackend.UseMoveForPutLong),
                      new CommandLineArgument(OPTION_FORCE_REAUTH, CommandLineArgument.ArgumentType.Boolean, Strings.FileBackend.ForceReauthShort, Strings.FileBackend.ForceReauthLong),
                  });
  
              }
          }
  
          public string Description
          {
              get
              {
                  return Strings.FileBackend.Description;
              }
          }
  
          public void Test()
          {
              List();
          }
  
          public void CreateFolder()
          {
              if (System.IO.Directory.Exists(m_path))
                  throw new FolderAreadyExistedException();
  
              System.IO.Directory.CreateDirectory(m_path);
          }
  
          #endregion
  
          #region IDisposable Members
  
          public void Dispose()
          {
              if (m_username != null)
                  m_username = null;
              if (m_password != null)
                  m_password = null;
          }
  
          #endregion
  
          public static bool PreAuthenticate(string path, string username, string password, bool forceReauth)
          {
              return Win32.PreAuthenticate(path, username, password, forceReauth);
          }
  
          private System.IO.DriveInfo GetDrive()
          {
              string root;
              if (Utility.Utility.IsClientLinux)
              {
                  string path = Utility.Utility.AppendDirSeparator(System.IO.Path.GetFullPath(m_path));
                  root = "/";
  
                  //Find longest common prefix from mounted devices
                  //TODO: Can trick this with symlinks, where the symlink is on one mounted volume,
                  // and the actual storage is on another
                  foreach (System.IO.DriveInfo di in System.IO.DriveInfo.GetDrives())
                      if (path.StartsWith(Utility.Utility.AppendDirSeparator(di.Name)) && di.Name.Length > root.Length)
                          root = di.Name;
              }
              else
              {
                  root = System.IO.Path.GetPathRoot(m_path);
              }
  
  
gt:             return new System.IO.DriveInfo(root);