Synnefo » Pithos MS Client

using System.Linq.Expressions;

    [DebuggerDisplay("{FilePath} C:{C} L:{L} S:{S}")]

    public class StateTuple

    {

        public string FilePath { get; private set; }

        public string L

        {

            get { return FileState==null?null:FileState.Checksum; }

        }

        public string C { get; set; }

        public string S

        {

            get { return ObjectInfo== null ? null : ObjectInfo.Hash; }

        }

        private FileSystemInfo _fileInfo;

        public FileSystemInfo FileInfo

        {

            get { return _fileInfo; }

            set

            {

                _fileInfo = value;

                FilePath = value.FullName;

            }

        }

        public FileState FileState { get; set; }

        public ObjectInfo ObjectInfo{ get; set; }

        public StateTuple() { }

        public StateTuple(FileSystemInfo info)

        {

            FileInfo = info;

        }

    }

        private CancellationTokenSource _currentOperationCancellation = new CancellationTokenSource();

        public void CancelCurrentOperation()

        {

            //What does it mean to cancel the current upload/download?

            //Obviously, the current operation will be cancelled by throwing

            //a cancellation exception.

            //

            //The default behavior is to retry any operations that throw.

            //Obviously this is not what we want in this situation.

            //The cancelled operation should NOT bea retried. 

            //

            //This can be done by catching the cancellation exception

            //and avoiding the retry.

            //

            //Have to reset the cancellation source - it is not possible to reset the source

            //Have to prevent a case where an operation requests a token from the old source

            var oldSource = Interlocked.Exchange(ref _currentOperationCancellation, new CancellationTokenSource());

            oldSource.Cancel();

        }

                                            orderby obj.Bytes ascending 

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

                        //Get the local files here                        

                        var agent = AgentLocator<FileAgent>.Get(accountInfo.AccountPath);

                        var files = LoadLocalFileTuples(accountInfo);

                        var states = FileState.Queryable.ToList();

                        var infos = (from remote in cleanRemotes

                                    let path = remote.RelativeUrlToFilePath(accountInfo.UserName)

                                    let info=agent.GetFileSystemInfo(path)

                                    select Tuple.Create(info.FullName,remote))

                                    .ToList();

                        var token = _currentOperationCancellation.Token;

                        var tuples = MergeSources(infos, files, states).ToList();

                        foreach (var tuple in tuples)

                            await _unPauseEvent.WaitAsync();

                            SyncSingleItem(accountInfo, tuple, agent, token);

                        //On the first run

/*

                        if (_firstPoll)

                        {

                            MarkSuspectedDeletes(accountInfo, cleanRemotes);

                        }

*/

        private static List<Tuple<FileSystemInfo, string>> LoadLocalFileTuples(AccountInfo accountInfo)

        {

            using (ThreadContext.Stacks["Account Files Hashing"].Push(accountInfo.UserName))

            {

                var localInfos = AgentLocator<FileAgent>.Get(accountInfo.AccountPath).EnumerateFileSystemInfos();

                //Use the queue to retry locked file hashing

                var fileQueue = new Queue<FileSystemInfo>(localInfos);

                var results = new List<Tuple<FileSystemInfo, string>>();

                while (fileQueue.Count > 0)

                {

                    var file = fileQueue.Dequeue();

                    using (ThreadContext.Stacks["File"].Push(file.FullName))

                    {

                        try

                        {

                            var hash = (file is DirectoryInfo)

                                           ? "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"

                                           : Signature.CalculateTreeHash(file, accountInfo.BlockSize,

                                                                         accountInfo.BlockHash)

                                                 .

                                                 TopHash.ToHashString();

                            results.Add(Tuple.Create(file, hash));

                        }

                        catch (IOException exc)

                        {

                            Log.WarnFormat("[HASH] File in use, will retry [{0}]", exc);

                            fileQueue.Enqueue(file);

                        }

                    }

                }

                return results;

            }

        }

        private void SyncSingleItem(AccountInfo accountInfo, StateTuple tuple, FileAgent agent, CancellationToken token)

        {

            Log.DebugFormat("Sync [{0}] C:[{1}] L:[{2}] S:[{3}]",tuple.FilePath,tuple.C,tuple.L,tuple.S);

            var localFilePath = tuple.FilePath;

            //Don't use the tuple info, it may have been deleted

            var localInfo = FileInfoExtensions.FromPath(localFilePath);

            // Local file unchanged? If both C and L are null, make sure it's because 

            //both the file is missing and the state checksum is not missing

            if (tuple.C == tuple.L && (localInfo.Exists || tuple.FileState==null))

            {

                //No local changes

                //Server unchanged?

                if (tuple.S == tuple.L)

                {

                    // No server changes

                    ;

                }

                else

                {

                    //Different from server

                    if (Selectives.IsSelected(accountInfo, localFilePath))

                    {

                        //Does the server file exist?

                        if (tuple.S == null)

                        {

                            //Server file doesn't exist

                            //deleteObjectFromLocal()

                            StatusKeeper.SetFileState(localFilePath, FileStatus.Deleted,

                                                      FileOverlayStatus.Deleted, "");

                            agent.Delete(localFilePath);

                            //updateRecord(Remove C, L)

                            StatusKeeper.ClearFileStatus(localFilePath);

                        }

                        else

                        {

                            //Server file exists

                            //downloadServerObject() // Result: L = S

                            StatusKeeper.SetFileState(localFilePath, FileStatus.Modified,

                                                      FileOverlayStatus.Modified, "");

                            NetworkAgent.Downloader.DownloadCloudFile(accountInfo,

                                                                            tuple.ObjectInfo,

                                                                            localFilePath, token).Wait(token);

                            //updateRecord( L = S )

                            StatusKeeper.UpdateFileChecksum(localFilePath, tuple.FileState==null?"":tuple.FileState.ShortHash,

                                                            tuple.ObjectInfo.Hash);

                            StatusKeeper.SetFileState(localFilePath, FileStatus.Unchanged,

                                                      FileOverlayStatus.Normal, "");

                        }

                    }

                }

            }

            else

            {

                //Local changes found

                //Server unchanged?

                if (tuple.S == tuple.L)

                {

                    //The FileAgent selective sync checks for new root folder files

                    if (!agent.Ignore(localFilePath))

                    {

                        if ((tuple.C == null || !localInfo.Exists) && tuple.ObjectInfo != null)

                        {

                            //deleteObjectFromServer()

                            DeleteCloudFile(accountInfo, tuple);

                            //updateRecord( Remove L, S)                  

                        }

                        else

                        {

                            //uploadLocalObject() // Result: S = C, L = S                        

                            var isUnselected = agent.IsUnselectedRootFolder(tuple.FilePath);

                            //Debug.Assert(tuple.FileState !=null);

                            var action = new CloudUploadAction(accountInfo, localInfo, tuple.FileState,

                                                               accountInfo.BlockSize, accountInfo.BlockHash,

                                                               "Poll", isUnselected);

                            NetworkAgent.Uploader.UploadCloudFile(action, token).Wait(token);

                            //updateRecord( S = C )

                            StatusKeeper.SetFileState(localFilePath, FileStatus.Unchanged,

                                                      FileOverlayStatus.Normal, "");

                            if (isUnselected)

                            {

                                ProcessChildren(accountInfo, tuple, agent, token);

                            }

                        }

                    }

                }

                else

                {

                    if (Selectives.IsSelected(accountInfo, localFilePath))

                    {

                        if (tuple.C == tuple.S)

                        {

                            // (Identical Changes) Result: L = S

                            //doNothing()

                            StatusKeeper.UpdateFileChecksum(localFilePath, tuple.FileState == null ? "" : tuple.FileState.ShortHash,

                                                            tuple.ObjectInfo.Hash);

                            StatusKeeper.SetFileState(localFilePath, FileStatus.Unchanged,

                                                      FileOverlayStatus.Normal, "");

                        }

                        else

                        {

                            if ((tuple.C == null || !localInfo.Exists) && tuple.ObjectInfo != null )

                            {

                                //deleteObjectFromServer()

                                DeleteCloudFile(accountInfo, tuple);

                                //updateRecord(Remove L, S)                  

                            }

                            else

                            {

                                ReportConflictForMismatch(localFilePath);

                                //identifyAsConflict() // Manual action required

                            }

                        }

                    }

                }

            }

        }

        private void DeleteCloudFile(AccountInfo accountInfo, StateTuple tuple)

        {

            StatusKeeper.SetFileState(tuple.FilePath, FileStatus.Deleted,

                                      FileOverlayStatus.Deleted, "");

            NetworkAgent.DeleteAgent.DeleteCloudFile(accountInfo, tuple.ObjectInfo);

            StatusKeeper.ClearFileStatus(tuple.FilePath);

        }

        private void ProcessChildren(AccountInfo accountInfo, StateTuple tuple, FileAgent agent, CancellationToken token)

        {

            var dirInfo = tuple.FileInfo as DirectoryInfo;

            var folderTuples = from folder in dirInfo.EnumerateDirectories("*", SearchOption.AllDirectories)

                               select new StateTuple(folder);

            var fileTuples = from file in dirInfo.EnumerateFiles("*", SearchOption.AllDirectories)

                             select new StateTuple(file);

            //Process folders first, to ensure folders appear on the sever as soon as possible

            folderTuples.ApplyAction(t => SyncSingleItem(accountInfo, t, agent, token));

            fileTuples.ApplyAction(t => SyncSingleItem(accountInfo, t, agent, token));

        }

        private static IEnumerable<StateTuple> MergeSources(

            IEnumerable<Tuple<string, ObjectInfo>> infos, 

            IEnumerable<Tuple<FileSystemInfo, string>> files, 

            IEnumerable<FileState> states)

        {

            var dct = new Dictionary<string, StateTuple>();

            foreach (var file in files)

            {

                var fsInfo = file.Item1;

                var fileHash = file.Item2;

                dct[fsInfo.FullName] = new StateTuple {FileInfo = fsInfo, C = fileHash};

            }

            foreach (var state in states)

            {

                StateTuple hashTuple;

                if (dct.TryGetValue(state.FilePath, out hashTuple))

                {

                    hashTuple.FileState = state;

                }

                else

                {

                    var fsInfo = FileInfoExtensions.FromPath(state.FilePath);

                    dct[state.FilePath] = new StateTuple {FileInfo = fsInfo, FileState = state};

                }

            }

            foreach (var info in infos)

            {

                StateTuple hashTuple;

                var filePath = info.Item1;

                var objectInfo = info.Item2;

                if (dct.TryGetValue(filePath, out hashTuple))

                {

                    hashTuple.ObjectInfo = objectInfo;

                }

                else

                {

                    var fsInfo = FileInfoExtensions.FromPath(filePath);

                    dct[filePath] = new StateTuple {FileInfo = fsInfo, ObjectInfo = objectInfo};

                }

            }

            return dct.Values;

        }

        //readonly AccountsDifferencer _differencer = new AccountsDifferencer();

        private void ReportConflictForMismatch(string localFilePath)

        {

            if (String.IsNullOrWhiteSpace(localFilePath))

                throw new ArgumentNullException("localFilePath");

            Contract.EndContractBlock();

            StatusKeeper.SetFileState(localFilePath, FileStatus.Conflict, FileOverlayStatus.Conflict, "File changed at the server");

            UpdateStatus(PithosStatus.HasConflicts);

            var message = String.Format("Conflict detected for file {0}", localFilePath);

            Log.Warn(message);

            StatusNotification.NotifyChange(message, TraceLevel.Warning);

        }

/*

*/