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#region
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/* -----------------------------------------------------------------------
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 * <copyright file="PollAgent.cs" company="GRNet">
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 * 
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 * Copyright 2011-2012 GRNET S.A. All rights reserved.
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 *
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 * Redistribution and use in source and binary forms, with or
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 * without modification, are permitted provided that the following
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 * conditions are met:
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 *
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 *   1. Redistributions of source code must retain the above
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 *      copyright notice, this list of conditions and the following
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 *      disclaimer.
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 *
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 *   2. Redistributions in binary form must reproduce the above
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 *      copyright notice, this list of conditions and the following
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 *      disclaimer in the documentation and/or other materials
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 *      provided with the distribution.
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 *
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 *
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 * THIS SOFTWARE IS PROVIDED BY GRNET S.A. ``AS IS'' AND ANY EXPRESS
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 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL GRNET S.A OR
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 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
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 * USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
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 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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 * POSSIBILITY OF SUCH DAMAGE.
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 *
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 * The views and conclusions contained in the software and
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 * documentation are those of the authors and should not be
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 * interpreted as representing official policies, either expressed
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 * or implied, of GRNET S.A.
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 * </copyright>
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 * -----------------------------------------------------------------------
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 */
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#endregion
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43
using System.Collections.Concurrent;
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using System.ComponentModel.Composition;
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using System.Diagnostics;
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using System.Diagnostics.Contracts;
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using System.IO;
48
using System.Reflection;
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using System.Threading;
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using System.Threading.Tasks;
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using Castle.ActiveRecord;
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using Pithos.Interfaces;
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using Pithos.Network;
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using log4net;
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56
namespace Pithos.Core.Agents
57
{
58
    using System;
59
    using System.Collections.Generic;
60
    using System.Linq;
61

    
62
    /// <summary>
63
    /// PollAgent periodically polls the server to detect object changes. The agent retrieves a listing of all
64
    /// objects and compares it with a previously cached version to detect differences. 
65
    /// New files are downloaded, missing files are deleted from the local file system and common files are compared
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    /// to determine the appropriate action
67
    /// </summary>
68
    [Export]
69
    public class PollAgent
70
    {
71
        private static readonly ILog Log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
72

    
73
        [System.ComponentModel.Composition.Import]
74
        public IStatusKeeper StatusKeeper { get; set; }
75

    
76
        [System.ComponentModel.Composition.Import]
77
        public IPithosSettings Settings { get; set; }
78

    
79
        [System.ComponentModel.Composition.Import]
80
        public NetworkAgent NetworkAgent { get; set; }
81

    
82
        public IStatusNotification StatusNotification { get; set; }
83

    
84
        private bool _firstPoll = true;
85

    
86
        //The Sync Event signals a manual synchronisation
87
        private readonly AsyncManualResetEvent _syncEvent = new AsyncManualResetEvent();
88

    
89
        private readonly ConcurrentDictionary<string, DateTime> _lastSeen = new ConcurrentDictionary<string, DateTime>();
90
        private readonly ConcurrentDictionary<string, AccountInfo> _accounts = new ConcurrentDictionary<string,AccountInfo>();
91

    
92

    
93
        /// <summary>
94
        /// Start a manual synchronization
95
        /// </summary>
96
        public void SynchNow()
97
        {            
98
            _syncEvent.Set();
99
        }
100

    
101
        /// <summary>
102
        /// Remote files are polled periodically. Any changes are processed
103
        /// </summary>
104
        /// <param name="since"></param>
105
        /// <returns></returns>
106
        public async Task PollRemoteFiles(DateTime? since = null)
107
        {
108
            if (Log.IsDebugEnabled)
109
                Log.DebugFormat("Polling changes after [{0}]",since);
110

    
111
            Debug.Assert(Thread.CurrentThread.IsBackground, "Polling Ended up in the main thread!");
112
            
113

    
114
            using (ThreadContext.Stacks["Retrieve Remote"].Push("All accounts"))
115
            {
116
                //If this poll fails, we will retry with the same since value
117
                var nextSince = since;
118
                try
119
                {
120
                    UpdateStatus(PithosStatus.PollSyncing);
121

    
122
                    var tasks = from accountInfo in _accounts.Values
123
                                select ProcessAccountFiles(accountInfo, since);
124

    
125
                    var nextTimes=await TaskEx.WhenAll(tasks.ToList());
126

    
127
                    _firstPoll = false;
128
                    //Reschedule the poll with the current timestamp as a "since" value
129

    
130
                    if (nextTimes.Length>0)
131
                        nextSince = nextTimes.Min();
132
                    if (Log.IsDebugEnabled)
133
                        Log.DebugFormat("Next Poll at [{0}]",nextSince);
134
                }
135
                catch (Exception ex)
136
                {
137
                    Log.ErrorFormat("Error while processing accounts\r\n{0}", ex);
138
                    //In case of failure retry with the same "since" value
139
                }
140

    
141
                UpdateStatus(PithosStatus.PollComplete);
142
                //The multiple try blocks are required because we can't have an await call
143
                //inside a finally block
144
                //TODO: Find a more elegant solution for reschedulling in the event of an exception
145
                try
146
                {
147
                    //Wait for the polling interval to pass or the Sync event to be signalled
148
                    nextSince = await WaitForScheduledOrManualPoll(nextSince);
149
                }
150
                finally
151
                {
152
                    //Ensure polling is scheduled even in case of error
153
                    TaskEx.Run(() => PollRemoteFiles(nextSince));                        
154
                }
155
            }
156
        }
157

    
158
        /// <summary>
159
        /// Wait for the polling period to expire or a manual sync request
160
        /// </summary>
161
        /// <param name="since"></param>
162
        /// <returns></returns>
163
        private async Task<DateTime?> WaitForScheduledOrManualPoll(DateTime? since)
164
        {
165
            var sync = _syncEvent.WaitAsync();
166
            var wait = TaskEx.Delay(TimeSpan.FromSeconds(Settings.PollingInterval), NetworkAgent.CancellationToken);
167
            var signaledTask = await TaskEx.WhenAny(sync, wait);
168

    
169
            //Wait for network processing to finish before polling
170
            var pauseTask=NetworkAgent.ProceedEvent.WaitAsync();
171
            await TaskEx.WhenAll(signaledTask, pauseTask);
172

    
173
            //If polling is signalled by SynchNow, ignore the since tag
174
            if (sync.IsCompleted)
175
            {
176
                //TODO: Must convert to AutoReset
177
                _syncEvent.Reset();
178
                return null;
179
            }
180
            return since;
181
        }
182

    
183
        public async Task<DateTime?> ProcessAccountFiles(AccountInfo accountInfo, DateTime? since = null)
184
        {
185
            if (accountInfo == null)
186
                throw new ArgumentNullException("accountInfo");
187
            if (String.IsNullOrWhiteSpace(accountInfo.AccountPath))
188
                throw new ArgumentException("The AccountInfo.AccountPath is empty", "accountInfo");
189
            Contract.EndContractBlock();
190

    
191

    
192
            using (ThreadContext.Stacks["Retrieve Remote"].Push(accountInfo.UserName))
193
            {
194

    
195
                await NetworkAgent.GetDeleteAwaiter();
196

    
197
                Log.Info("Scheduled");
198
                var client = new CloudFilesClient(accountInfo);
199

    
200
                //We don't need to check the trash container
201
                var containers = client.ListContainers(accountInfo.UserName)
202
                    .Where(c=>c.Name!="trash")
203
                    .ToList();
204

    
205

    
206
                CreateContainerFolders(accountInfo, containers);
207

    
208
                //The nextSince time fallback time is the same as the current.
209
                //If polling succeeds, the next Since time will be the smallest of the maximum modification times
210
                //of the shared and account objects
211
                var nextSince = since;
212

    
213
                try
214
                {
215
                    //Wait for any deletions to finish
216
                    await NetworkAgent.GetDeleteAwaiter();
217
                    //Get the poll time now. We may miss some deletions but it's better to keep a file that was deleted
218
                    //than delete a file that was created while we were executing the poll                    
219

    
220
                    //Get the list of server objects changed since the last check
221
                    //The name of the container is passed as state in order to create a dictionary of tasks in a subsequent step
222
                    var listObjects = (from container in containers
223
                                       select Task<IList<ObjectInfo>>.Factory.StartNew(_ =>
224
                                             client.ListObjects(accountInfo.UserName, container.Name, since), container.Name)).ToList();
225

    
226
                    var listShared = Task<IList<ObjectInfo>>.Factory.StartNew(_ => 
227
                        client.ListSharedObjects(since), "shared");
228
                    listObjects.Add(listShared);
229
                    var listTasks = await Task.Factory.WhenAll(listObjects.ToArray());
230

    
231
                    using (ThreadContext.Stacks["SCHEDULE"].Push("Process Results"))
232
                    {
233
                        var dict = listTasks.ToDictionary(t => t.AsyncState);
234

    
235
                        //Get all non-trash objects. Remember, the container name is stored in AsyncState
236
                        var remoteObjects = (from objectList in listTasks
237
                                            where (string)objectList.AsyncState != "trash"
238
                                            from obj in objectList.Result
239
                                            select obj).ToList();
240
                        
241
                        //Get the latest remote object modification date, only if it is after
242
                        //the original since date
243
                        nextSince = GetLatestDateAfter(nextSince, remoteObjects);
244

    
245
                        var sharedObjects = dict["shared"].Result;
246
                        nextSince = GetLatestDateBefore(nextSince, sharedObjects);
247

    
248
                        //DON'T process trashed files
249
                        //If some files are deleted and added again to a folder, they will be deleted
250
                        //even though they are new.
251
                        //We would have to check file dates and hashes to ensure that a trashed file
252
                        //can be deleted safely from the local hard drive.
253
                        /*
254
                        //Items with the same name, hash may be both in the container and the trash
255
                        //Don't delete items that exist in the container
256
                        var realTrash = from trash in trashObjects
257
                                        where
258
                                            !remoteObjects.Any(
259
                                                info => info.Name == trash.Name && info.Hash == trash.Hash)
260
                                        select trash;
261
                        ProcessTrashedFiles(accountInfo, realTrash);
262
*/
263

    
264
                        var cleanRemotes = (from info in remoteObjects.Union(sharedObjects)
265
                                            let name = info.Name??""
266
                                            where !name.EndsWith(".ignore", StringComparison.InvariantCultureIgnoreCase) &&
267
                                                  !name.StartsWith(FolderConstants.CacheFolder + "/",
268
                                                                   StringComparison.InvariantCultureIgnoreCase)
269
                                            select info).ToList();
270

    
271
                        var differencer = _differencer.PostSnapshot(accountInfo, cleanRemotes);
272

    
273
                        ProcessDeletedFiles(accountInfo, differencer.Deleted.FilterDirectlyBelow(SelectiveUris));
274

    
275
                        // @@@ NEED To add previous state here as well, To compare with previous hash
276

    
277
                        
278

    
279
                        //Create a list of actions from the remote files
280
                        var allActions = MovesToActions(accountInfo,differencer.Moved.FilterDirectlyBelow(SelectiveUris))
281
                                        .Union(
282
                                        ChangesToActions(accountInfo, differencer.Changed.FilterDirectlyBelow(SelectiveUris)))
283
                                        .Union(
284
                                        CreatesToActions(accountInfo, differencer.Created.FilterDirectlyBelow(SelectiveUris)));
285

    
286
                        //And remove those that are already being processed by the agent
287
                        var distinctActions = allActions
288
                            .Except(NetworkAgent.GetEnumerable(), new LocalFileComparer())
289
                            .ToList();
290

    
291
                        //Queue all the actions
292
                        foreach (var message in distinctActions)
293
                        {
294
                            NetworkAgent.Post(message);
295
                        }
296

    
297
                        Log.Info("[LISTENER] End Processing");
298
                    }
299
                }
300
                catch (Exception ex)
301
                {
302
                    Log.ErrorFormat("[FAIL] ListObjects for{0} in ProcessRemoteFiles with {1}", accountInfo.UserName, ex);
303
                    return nextSince;
304
                }
305

    
306
                Log.Info("[LISTENER] Finished");
307
                return nextSince;
308
            }
309
        }
310

    
311
        /// <summary>
312
        /// Returns the latest LastModified date from the list of objects, but only if it is before
313
        /// than the threshold value
314
        /// </summary>
315
        /// <param name="threshold"></param>
316
        /// <param name="cloudObjects"></param>
317
        /// <returns></returns>
318
        private static DateTime? GetLatestDateBefore(DateTime? threshold, IList<ObjectInfo> cloudObjects)
319
        {
320
            DateTime? maxDate = null;
321
            if (cloudObjects!=null &&  cloudObjects.Count > 0)
322
                maxDate = cloudObjects.Max(obj => obj.Last_Modified);
323
            if (maxDate == null || maxDate == DateTime.MinValue)
324
                return threshold;
325
            if (threshold == null || threshold == DateTime.MinValue || threshold > maxDate)
326
                return maxDate;
327
            return threshold;
328
        }
329

    
330
        /// <summary>
331
        /// Returns the latest LastModified date from the list of objects, but only if it is after
332
        /// the threshold value
333
        /// </summary>
334
        /// <param name="threshold"></param>
335
        /// <param name="cloudObjects"></param>
336
        /// <returns></returns>
337
        private static DateTime? GetLatestDateAfter(DateTime? threshold, IList<ObjectInfo> cloudObjects)
338
        {
339
            DateTime? maxDate = null;
340
            if (cloudObjects!=null &&  cloudObjects.Count > 0)
341
                maxDate = cloudObjects.Max(obj => obj.Last_Modified);
342
            if (maxDate == null || maxDate == DateTime.MinValue)
343
                return threshold;
344
            if (threshold == null || threshold == DateTime.MinValue || threshold < maxDate)
345
                return maxDate;
346
            return threshold;
347
        }
348

    
349
        readonly AccountsDifferencer _differencer = new AccountsDifferencer();
350
        private List<Uri> _selectiveUris=new List<Uri>();
351

    
352
        /// <summary>
353
        /// Deletes local files that are not found in the list of cloud files
354
        /// </summary>
355
        /// <param name="accountInfo"></param>
356
        /// <param name="cloudFiles"></param>
357
        private void ProcessDeletedFiles(AccountInfo accountInfo, IEnumerable<ObjectInfo> cloudFiles)
358
        {
359
            if (accountInfo == null)
360
                throw new ArgumentNullException("accountInfo");
361
            if (String.IsNullOrWhiteSpace(accountInfo.AccountPath))
362
                throw new ArgumentException("The AccountInfo.AccountPath is empty", "accountInfo");
363
            if (cloudFiles == null)
364
                throw new ArgumentNullException("cloudFiles");
365
            Contract.EndContractBlock();
366

    
367
            //On the first run
368
            if (_firstPoll)
369
            {
370
                //Only consider files that are not being modified, ie they are in the Unchanged state            
371
                var deleteCandidates = FileState.Queryable.Where(state =>
372
                    state.FilePath.StartsWith(accountInfo.AccountPath)
373
                    && state.FileStatus == FileStatus.Unchanged).ToList();
374

    
375

    
376
                //TODO: filesToDelete must take into account the Others container            
377
                var filesToDelete = (from deleteCandidate in deleteCandidates
378
                                     let localFile = FileInfoExtensions.FromPath(deleteCandidate.FilePath)
379
                                     let relativeFilePath = localFile.AsRelativeTo(accountInfo.AccountPath)
380
                                     where
381
                                         !cloudFiles.Any(r => r.RelativeUrlToFilePath(accountInfo.UserName) == relativeFilePath)
382
                                     select localFile).ToList();
383

    
384

    
385

    
386
                //Set the status of missing files to Conflict
387
                foreach (var item in filesToDelete)
388
                {
389
                    //Try to acquire a gate on the file, to take into account files that have been dequeued
390
                    //and are being processed
391
                    using (var gate = NetworkGate.Acquire(item.FullName, NetworkOperation.Deleting))
392
                    {
393
                        if (gate.Failed)
394
                            continue;
395
                        StatusKeeper.SetFileState(item.FullName, FileStatus.Conflict, FileOverlayStatus.Deleted);
396
                    }
397
                }
398
                UpdateStatus(PithosStatus.HasConflicts);
399
                StatusNotification.NotifyConflicts(filesToDelete, String.Format("{0} local files are missing from Pithos, possibly because they were deleted", filesToDelete.Count));
400
                StatusNotification.NotifyForFiles(filesToDelete, String.Format("{0} files were deleted", filesToDelete.Count), TraceLevel.Info);
401
            }
402
            else
403
            {
404
                var deletedFiles = new List<FileSystemInfo>();
405
                foreach (var objectInfo in cloudFiles)
406
                {
407
                    if (Log.IsDebugEnabled)
408
                        Log.DebugFormat("Handle deleted [{0}]",objectInfo.Uri);
409
                    var relativePath = objectInfo.RelativeUrlToFilePath(accountInfo.UserName);
410
                    var item = FileAgent.GetFileAgent(accountInfo).GetFileSystemInfo(relativePath);
411
                    if (Log.IsDebugEnabled)
412
                        Log.DebugFormat("Will delete [{0}] for [{1}]", item.FullName,objectInfo.Uri);
413
                    if (item.Exists)
414
                    {
415
                        if ((item.Attributes & FileAttributes.ReadOnly) == FileAttributes.ReadOnly)
416
                        {
417
                            item.Attributes = item.Attributes & ~FileAttributes.ReadOnly;
418

    
419
                        }
420
                        
421
                        
422
                        Log.DebugFormat("Deleting {0}", item.FullName);
423

    
424
                        var directory = item as DirectoryInfo;
425
                        if (directory!=null)
426
                            directory.Delete(true);
427
                        else
428
                            item.Delete();
429
                        Log.DebugFormat("Deleted [{0}] for [{1}]", item.FullName, objectInfo.Uri);
430
                        DateTime lastDate;
431
                        _lastSeen.TryRemove(item.FullName, out lastDate);
432
                        deletedFiles.Add(item);
433
                    }
434
                    StatusKeeper.SetFileState(item.FullName, FileStatus.Deleted, FileOverlayStatus.Deleted);
435
                }
436
                Log.InfoFormat("[{0}] files were deleted",deletedFiles.Count);
437
                StatusNotification.NotifyForFiles(deletedFiles, String.Format("{0} files were deleted", deletedFiles.Count), TraceLevel.Info);
438
            }
439

    
440
        }
441

    
442
        /// <summary>
443
        /// Creates a Sync action for each changed server file
444
        /// </summary>
445
        /// <param name="accountInfo"></param>
446
        /// <param name="changes"></param>
447
        /// <returns></returns>
448
        private IEnumerable<CloudAction> ChangesToActions(AccountInfo accountInfo, IEnumerable<ObjectInfo> changes)
449
        {
450
            if (changes == null)
451
                throw new ArgumentNullException();
452
            Contract.EndContractBlock();
453
            var fileAgent = FileAgent.GetFileAgent(accountInfo);
454

    
455
            //In order to avoid multiple iterations over the files, we iterate only once
456
            //over the remote files
457
            foreach (var objectInfo in changes)
458
            {
459
                var relativePath = objectInfo.RelativeUrlToFilePath(accountInfo.UserName);
460
                //If a directory object already exists, we may need to sync it
461
                if (fileAgent.Exists(relativePath))
462
                {
463
                    var localFile = fileAgent.GetFileSystemInfo(relativePath);
464
                    //We don't need to sync directories
465
                    if (objectInfo.Content_Type == @"application/directory" && localFile is DirectoryInfo)
466
                        continue;
467
                    using (new SessionScope(FlushAction.Never))
468
                    {
469
                        var state = StatusKeeper.GetStateByFilePath(localFile.FullName);
470
                        _lastSeen[localFile.FullName] = DateTime.Now;
471
                        //Common files should be checked on a per-case basis to detect differences, which is newer
472

    
473
                        yield return new CloudAction(accountInfo, CloudActionType.MustSynch,
474
                                                     localFile, objectInfo, state, accountInfo.BlockSize,
475
                                                     accountInfo.BlockHash);
476
                    }
477
                }
478
                else
479
                {
480
                    //Remote files should be downloaded
481
                    yield return new CloudDownloadAction(accountInfo, objectInfo);
482
                }
483
            }
484
        }
485

    
486
        /// <summary>
487
        /// Creates a Local Move action for each moved server file
488
        /// </summary>
489
        /// <param name="accountInfo"></param>
490
        /// <param name="moves"></param>
491
        /// <returns></returns>
492
        private IEnumerable<CloudAction> MovesToActions(AccountInfo accountInfo, IEnumerable<ObjectInfo> moves)
493
        {
494
            if (moves == null)
495
                throw new ArgumentNullException();
496
            Contract.EndContractBlock();
497
            var fileAgent = FileAgent.GetFileAgent(accountInfo);
498

    
499
            //In order to avoid multiple iterations over the files, we iterate only once
500
            //over the remote files
501
            foreach (var objectInfo in moves)
502
            {
503
                var previousRelativepath = objectInfo.Previous.RelativeUrlToFilePath(accountInfo.UserName);
504
                //If the previous file already exists, we can execute a Move operation
505
                if (fileAgent.Exists(previousRelativepath))
506
                {
507
                    var previousFile = fileAgent.GetFileSystemInfo(previousRelativepath);
508
                    using (new SessionScope(FlushAction.Never))
509
                    {
510
                        var state = StatusKeeper.GetStateByFilePath(previousFile.FullName);
511
                        _lastSeen[previousFile.FullName] = DateTime.Now;
512

    
513
                        //For each moved object we need to move both the local file and update                                                
514
                        yield return new CloudAction(accountInfo, CloudActionType.RenameLocal,
515
                                                     previousFile, objectInfo, state, accountInfo.BlockSize,
516
                                                     accountInfo.BlockHash);
517
                        //For modified files, we need to download the changes as well
518
                        if (objectInfo.Hash!=objectInfo.PreviousHash)
519
                            yield return new CloudDownloadAction(accountInfo,objectInfo);
520
                    }
521
                }
522
                //If the previous file does not exist, we need to download it in the new location
523
                else
524
                {
525
                    //Remote files should be downloaded
526
                    yield return new CloudDownloadAction(accountInfo, objectInfo);
527
                }
528
            }
529
        }
530

    
531

    
532
        /// <summary>
533
        /// Creates a download action for each new server file
534
        /// </summary>
535
        /// <param name="accountInfo"></param>
536
        /// <param name="creates"></param>
537
        /// <returns></returns>
538
        private IEnumerable<CloudAction> CreatesToActions(AccountInfo accountInfo, IEnumerable<ObjectInfo> creates)
539
        {
540
            if (creates == null)
541
                throw new ArgumentNullException();
542
            Contract.EndContractBlock();
543
            var fileAgent = FileAgent.GetFileAgent(accountInfo);
544

    
545
            //In order to avoid multiple iterations over the files, we iterate only once
546
            //over the remote files
547
            foreach (var objectInfo in creates)
548
            {
549
                if (Log.IsDebugEnabled)
550
                    Log.DebugFormat("[NEW INFO] {0}",objectInfo.Uri);
551

    
552
                var relativePath = objectInfo.RelativeUrlToFilePath(accountInfo.UserName);
553
                //If the object already exists, we probably have a conflict
554
                if (fileAgent.Exists(relativePath))
555
                {
556
                    Log.DebugFormat("[SKIP EXISTING] {0}", objectInfo.Uri);
557
                    //If a directory object already exists, we don't need to perform any other action                    
558
                    var localFile = fileAgent.GetFileSystemInfo(relativePath);
559
                    StatusKeeper.SetFileState(localFile.FullName, FileStatus.Conflict, FileOverlayStatus.Conflict);
560
                }
561
                else
562
                {
563
                    //Remote files should be downloaded
564
                    yield return new CloudDownloadAction(accountInfo, objectInfo);
565
                }
566
            }
567
        }
568

    
569
        /// <summary>
570
        /// Notify the UI to update the visual status
571
        /// </summary>
572
        /// <param name="status"></param>
573
        private void UpdateStatus(PithosStatus status)
574
        {
575
            try
576
            {
577
                StatusNotification.SetPithosStatus(status);
578
                //StatusNotification.Notify(new Notification());
579
            }
580
            catch (Exception exc)
581
            {
582
                //Failure is not critical, just log it
583
                Log.Warn("Error while updating status", exc);
584
            }
585
        }
586

    
587
        private static void CreateContainerFolders(AccountInfo accountInfo, IEnumerable<ContainerInfo> containers)
588
        {
589
            var containerPaths = from container in containers
590
                                 let containerPath = Path.Combine(accountInfo.AccountPath, container.Name)
591
                                 where container.Name != FolderConstants.TrashContainer && !Directory.Exists(containerPath)
592
                                 select containerPath;
593

    
594
            foreach (var path in containerPaths)
595
            {
596
                Directory.CreateDirectory(path);
597
            }
598
        }
599

    
600
        public void SetSyncUris(Uri[] uris)
601
        {            
602
            SelectiveUris=uris.ToList();
603
        }
604

    
605
        protected List<Uri> SelectiveUris
606
        {
607
            get { return _selectiveUris;}
608
            set { _selectiveUris = value; }
609
        }
610

    
611
        public void AddAccount(AccountInfo accountInfo)
612
        {
613
            //Avoid adding a duplicate accountInfo
614
            _accounts.TryAdd(accountInfo.UserName, accountInfo);
615
        }
616

    
617
        public void RemoveAccount(AccountInfo accountInfo)
618
        {
619
            AccountInfo account;
620
            _accounts.TryRemove(accountInfo.UserName,out account);
621
            SnapshotDifferencer differencer;
622
            _differencer.Differencers.TryRemove(accountInfo.UserName, out differencer);
623
        }
624
    }
625
}