Engine Class

public abstract class Engine : IEngine, 
	IFileSystemFilter, IDisposable

Public MustInherit Class Engine
	Implements IEngine, IFileSystemFilter, IDisposable

public ref class Engine abstract : IEngine, 
	IFileSystemFilter, IDisposable

[<AbstractClassAttribute>]
type Engine =  
    class
        interface IEngine
        interface IFileSystemFilter
        interface IDisposable
    end

public class VirtualEngine : EngineWindows
{
    internal RemoteStorageMonitor RemoteStorageMonitor;

    internal readonly Mapping Mapping;

    public VirtualEngine(string license, string userFileSystemRootPath, string remoteStorageRootPath, LogFormatter logFormatter) :
        base(license, userFileSystemRootPath)
    {
        Mapping = new Mapping(Path, remoteStorageRootPath);

        // We want our file system to run regardless of any errors.
        // If any request to file system fails in user code or in Engine itself we continue processing.
        ThrowExceptions = false;

        StateChanged += Engine_StateChanged;
        ItemsChanged += Engine_ItemsChanged;
        SyncService.StateChanged += SyncService_StateChanged;
        Error += logFormatter.LogError;
        Message += logFormatter.LogMessage;
        Debug += logFormatter.LogDebug;

        RemoteStorageMonitor = new RemoteStorageMonitor(remoteStorageRootPath, this, this.Logger);
    }

    private void Engine_ItemsChanged(Engine sender, ItemsChangeEventArgs e)
    {
        var logger = Logger.CreateLogger(e.ComponentName);
        foreach (ChangeEventItem item in e.Items)
        {

            // If update from server failed becase a file is in use,
            // try to show merge dialog (for MS Office, etc.).
            if (e.Direction == SyncDirection.Incoming
                && e.OperationType == OperationType.UpdateContent)
            {
                switch (e.Result.Status)
                {
                    case OperationStatus.FileInUse:
                        ITHit.FileSystem.Windows.AppHelper.Utilities.TryNotifyUpdateAvailable(item.Path, e.Result.ShadowFilePath);
                        break;
                }
            }

            // Log info about the opertion.
            LogItemChange(e, item);
        }
    }

    private void LogItemChange(ItemsChangeEventArgs e, ChangeEventItem item)
    {
        var logger = Logger.CreateLogger(e.ComponentName);

        switch (e.Result.Status)
        {
            case OperationStatus.Success:
                switch (e.Source)
                {
                    case OperationSource.Server:
                        logger.LogMessage($"{e.Direction} {e.OperationType}: {e.Result.Status}", item.Path, item.NewPath, e.OperationContext, item.Metadata);
                        break;
                    case OperationSource.Client:
                        logger.LogDebug($"{e.Direction} {e.OperationType}: {e.Result.Status}", item.Path, item.NewPath, e.OperationContext, item.Metadata);
                        break;
                }
                break;
            case OperationStatus.Conflict:
                logger.LogMessage($"{e.Direction} {e.OperationType}: {e.Result.Status}", item.Path, item.NewPath, e.OperationContext, item.Metadata);
                break;
            case OperationStatus.Exception:
                logger.LogError($"{e.Direction} {e.OperationType}", item.Path, item.NewPath, e.Result.Exception, e.OperationContext, item.Metadata);
                break;
            case OperationStatus.Filtered:
                logger.LogDebug($"{e.Direction} {e.OperationType}: {e.Result.Status} by {e.Result.FilteredBy.GetType().Name}", item.Path, item.NewPath, e.OperationContext, item.Metadata);
                break;
            default:
                logger.LogDebug($"{e.Direction} {e.OperationType}: {e.Result.Status}. {e.Result.Message}", item.Path, item.NewPath, e.OperationContext, item.Metadata);
                break;
        }
    }

    public override async Task<bool> FilterAsync(SyncDirection direction, OperationType operationType, string path, FileSystemItemType itemType, string newPath, IOperationContext operationContext)
    {

        if (await new ZipFilter().FilterAsync(direction, operationType, path, itemType, newPath, operationContext))
        {
            return true;
        }

        if (await new MsOfficeFilter().FilterAsync(direction, operationType, path, itemType, newPath, operationContext))
        {
            return true;
        }

        if (await new AutoCadFilter().FilterAsync(direction, operationType, path, itemType, newPath, operationContext))
        {
            return true;
        }

        if (await new ErrorStatusFilter().FilterAsync(direction, operationType, path, itemType, newPath, operationContext))
        {
            return true;
        }

        return false;
    }

    public override async Task<IFileSystemItem> GetFileSystemItemAsync(byte[] remoteStorageItemId, FileSystemItemType itemType, IContext context, ILogger logger = null)
    {
        string userFileSystemPath = context.FileNameHint;
        if (itemType == FileSystemItemType.File)
        {
            return new VirtualFile(Mapping, userFileSystemPath, logger);
        }
        else
        {
            return new VirtualFolder(Mapping, userFileSystemPath, logger);
        }
    }

    public override async Task<IMenuCommand> GetMenuCommandAsync(Guid menuGuid, IOperationContext operationContext = null)
    {
        // For this method to be called you need to register a menu command handler.
        // See method description for more details.

        throw new NotImplementedException();
    }

    public override async Task StartAsync(bool processModified = true, CancellationToken cancellationToken = default)
    {
        await base.StartAsync(processModified, cancellationToken);
        await RemoteStorageMonitor.StartAsync();
    }

    public override async Task StopAsync()
    {
        await base.StopAsync();
        await RemoteStorageMonitor.StopAsync();
    }

    private void Engine_StateChanged(Engine engine, EngineWindows.StateChangeEventArgs e)
    {
        engine.Logger.LogMessage($"{e.NewState}", this.Path);
    }

    private void SyncService_StateChanged(object sender, SynchEventArgs e)
    {
        if (e.NewState == SynchronizationState.Enabled || e.NewState == SynchronizationState.Disabled)
        {
            SyncService.Logger.LogMessage($"{e.NewState}", this.Path);
        }
    }

    private bool disposedValue;

    protected override void Dispose(bool disposing)
    {
        if (!disposedValue)
        {
            if (disposing)
            {
                RemoteStorageMonitor.Dispose();
            }

            // TODO: free unmanaged resources (unmanaged objects) and override finalizer
            // TODO: set large fields to null
            disposedValue = true;
        }
        base.Dispose(disposing);
    }
}

public static async Task Main(string[] args)
{
    // Load Settings.
    Settings = new ConfigurationBuilder().AddJsonFile("appsettings.json", false, true).Build().ReadSettings();

    logFormatter = new LogFormatter(log, Settings.AppID);
    WindowManager.ConfigureConsole();

    // Log environment description.
    logFormatter.PrintEnvironmentDescription();

    registrar = new Registrar(log);
    consoleProcessor = new ConsoleProcessor(registrar, logFormatter, Settings.AppID);

    try
    {
        // Register sync root and create app folders.
        await registrar.RegisterSyncRootAsync(
            SyncRootId, 
            Settings.UserFileSystemRootPath, 
            Settings.RemoteStorageRootPath,
            Settings.ProductName, 
            Path.Combine(Settings.IconsFolderPath, "Drive.ico"));

        using (Engine = new VirtualEngine(
            Settings.UserFileSystemLicense,
            Settings.UserFileSystemRootPath,
            Settings.RemoteStorageRootPath,
            logFormatter))
        {
            commands = new Commands(Engine, Settings.RemoteStorageRootPath, log);
            commands.RemoteStorageMonitor = Engine.RemoteStorageMonitor;
            consoleProcessor.Commands.TryAdd(Guid.Empty, commands);

            // Here we disable incoming sync. To get changes from your remote storage using pooling, call the IncomingPooling.ProcessAsync() method.
            Engine.SyncService.IncomingSyncMode = ITHit.FileSystem.Synchronization.IncomingSyncMode.Disabled;

            // Set the remote storage item ID for the root item. It will be passed to the IEngine.GetFileSystemItemAsync()
            // method as a remoteStorageItemId parameter when a root folder is requested. 
            // In this sample we do not set the ID becuse in case of a network path the ID is not available.
            //Engine.SetRemoteStorageRootItemId(rootItemId);

            // Print console commands.
            consoleProcessor.PrintHelp();

            // Print Engine config, settings, logging headers.
            await logFormatter.PrintEngineStartInfoAsync(Engine, Settings.RemoteStorageRootPath);

            // Start processing OS file system calls.
            await Engine.StartAsync();

            // Sync all changes from remote storage one time for demo purposes.
            await Engine.SyncService.IncomingPooling.ProcessAsync();
G
            // Opens Windows File Manager with user file system folder and remote storage folder.
            commands.ShowTestEnvironment(Settings.ProductName);
#endif
            // Keep this application running and reading user input.
            await consoleProcessor.ProcessUserInputAsync();
        }
    }
    catch (Exception ex)
    {
        log.Error(ex);
        await consoleProcessor.ProcessUserInputAsync();
    }
}