code.grnet.gr Git - pithos-ms-client/blob - trunk/Pithos.Core/PithosWorkflow.cs

   1 using System;
   2 using System.Collections.Generic;
   3 using System.ComponentModel.Composition;
   4 using System.Linq;
   5 using System.Runtime.InteropServices;
   6 using System.Text;
   7 using System.Threading;
   8 using System.Threading.Tasks;
   9 using Pithos.Interfaces;
  10 using System.IO;
  11
  12 namespace Pithos.Core
  13 {
  14     [Export(typeof(IPithosWorkflow))]
  15     public class PithosWorkflow:IPithosWorkflow
  16     {
  17         [Import]
  18         public IPithosSettings Settings { get; set; }
  19
  20         [Import]
  21         public IStatusKeeper StatusKeeper { get; set; }
  22
  23         public FileStatus SetFileStatus(string path, FileStatus status)
  24         {
  25             if (String.IsNullOrWhiteSpace(path))
  26                 throw new ArgumentNullException("path", "The path parameter must not be emtpy");
  27
  28             var oldStatus=StatusKeeper.GetFileStatus(path);
  29
  30             if (oldStatus == status)
  31                 return oldStatus;
  32
  33             switch(oldStatus)
  34             {
  35                 case FileStatus.Unchanged :
  36                     break;
  37                 case FileStatus.Created:
  38                     if (status == FileStatus.Modified)
  39                         return oldStatus;
  40                     break;
  41                 case FileStatus.Modified:
  42                 case FileStatus.Renamed:
  43                     if (status == FileStatus.Created)
  44                         return oldStatus;
  45                     break;
  46                 case FileStatus.Deleted:
  47                     return oldStatus;
  48             }
  49             StatusKeeper.SetFileStatus(path, status);
  50             return status;
  51         }
  52
  53         public void ClearFileStatus(string path)
  54         {
  55             if (String.IsNullOrWhiteSpace(path))
  56                 throw new ArgumentNullException("path", "The path parameter must not be emtpy");
  57
  58             StatusKeeper.ClearFileStatus(path);
  59         }
  60
  61         public void RaiseChangeNotification(string path)
  62         {
  63             if (String.IsNullOrWhiteSpace(path))
  64                 throw new ArgumentNullException("path", "The path parameter must not be emtpy");
  65
  66             if (!Directory.Exists(path ) && !File.Exists(path))
  67                 throw new FileNotFoundException("The specified file or path does not exist",path);
  68
  69
  70             IntPtr pathPointer = Marshal.StringToCoTaskMemAuto(path);
  71
  72             try
  73             {
  74                 NativeMethods.SHChangeNotify(HChangeNotifyEventID.SHCNE_UPDATEITEM,
  75                                              HChangeNotifyFlags.SHCNF_PATHW | HChangeNotifyFlags.SHCNF_FLUSHNOWAIT,
  76                                              pathPointer, IntPtr.Zero);
  77             }
  78             finally
  79             {
  80                 Marshal.FreeHGlobal(pathPointer);
  81             }
  82
  83         }
  84
  85         public Task<FileStream> OpenStreamWithWaiting(string path)
  86         {
  87             if (String.IsNullOrWhiteSpace(path))
  88                 throw new ArgumentNullException("path","The path parameter must not be emtpy");
  89
  90             if (!File.Exists(path))
  91                 throw new FileNotFoundException("The specified file or path does not exist", path);
  92
  93             return new Task<FileStream>(() =>
  94                     {
  95                         int counter = 0;
  96                         while (true)
  97                         {
  98                             try
  99                             {
 100                                 var stream=File.OpenRead(path);
 101                                 return stream;
 102                             }
 103                             catch (Exception ex)
 104                             {
 105                                 Thread.Sleep(500);
 106                                 if (++counter > 10)
 107                                     throw;
 108                             }
 109                         }
 110                     });
 111         }
 112     }
 113 }