IFolder Interface

public interface IFolder : IFileSystemItem

Public Interface IFolder
	Inherits IFileSystemItem

public interface class IFolder : IFileSystemItem

type IFolder =  
    interface
        interface IFileSystemItem
    end

internal class VfsFolder : VfsFileSystemItem, IFolder
{
    public VfsFolder(string path, ILogger logger, VfsEngine engine) : base(path, logger, engine)
    {

    }

    public async Task GetChildrenAsync(string pattern, IOperationContext operationContext, IFolderListingResultContext resultContext)
    {
        // This method has a 60 sec timeout. 
        // To process longer requests and reset the timout timer call one of the following:
        // - resultContext.ReturnChildren() method.
        // - resultContext.ReportProgress() method.

        Logger.LogMessage($"IFolder.GetChildrenAsync({pattern})", UserFileSystemPath);

        IEnumerable<FileSystemItemBasicInfo> children = await new UserFolder(UserFileSystemPath).EnumerateChildrenAsync(pattern);

        // Filtering existing files/folders. This is only required to avoid extra errors in the log.
        List<IFileSystemItemBasicInfo> newChildren = new List<IFileSystemItemBasicInfo>();
        foreach (IFileSystemItemBasicInfo child in children)
        {
            string userFileSystemItemPath = Path.Combine(UserFileSystemPath, child.Name);
            if (!FsPath.Exists(userFileSystemItemPath))
            {
                Logger.LogMessage("Creating", child.Name);
                newChildren.Add(child);
            }
        }

        // To signal that the children enumeration is completed 
        // always call ReturnChildren(), even if the folder is empty.
        resultContext.ReturnChildren(newChildren.ToArray(), newChildren.Count());


        // Create ETags.
        // ETags must correspond with a server file/folder, NOT with a client placeholder. 
        // It should NOT be moved/deleted/updated when a placeholder in the user file system is moved/deleted/updated.
        // It should be moved/deleted when a file/folder in the remote storage is moved/deleted.
        foreach (FileSystemItemBasicInfo child in children)
        {
            string userFileSystemItemPath = Path.Combine(UserFileSystemPath, child.Name);
            await ETag.SetETagAsync(userFileSystemItemPath, child.ETag);
        }
    }
}

internal class VfsFolder : VfsFileSystemItem, IFolder
{
    public VfsFolder(string path, ILogger logger, VfsEngine engine) : base(path, logger, engine)
    {

    }

    public async Task GetChildrenAsync(string pattern, IOperationContext operationContext, IFolderListingResultContext resultContext)
    {
        // This method has a 60 sec timeout. 
        // To process longer requests and reset the timout timer call one of the following:
        // - resultContext.ReturnChildren() method.
        // - resultContext.ReportProgress() method.

        Logger.LogMessage($"IFolder.GetChildrenAsync({pattern})", UserFileSystemPath);

        IEnumerable<FileSystemItemBasicInfo> children = await new UserFolder(UserFileSystemPath).EnumerateChildrenAsync(pattern);

        // Filtering existing files/folders. This is only required to avoid extra errors in the log.
        List<IFileSystemItemBasicInfo> newChildren = new List<IFileSystemItemBasicInfo>();
        foreach (IFileSystemItemBasicInfo child in children)
        {
            string userFileSystemItemPath = Path.Combine(UserFileSystemPath, child.Name);
            if (!FsPath.Exists(userFileSystemItemPath))
            {
                Logger.LogMessage("Creating", child.Name);
                newChildren.Add(child);
            }
        }

        // To signal that the children enumeration is completed 
        // always call ReturnChildren(), even if the folder is empty.
        resultContext.ReturnChildren(newChildren.ToArray(), newChildren.Count());


        // Save ETags and set "locked by another user" icon.
        foreach (FileSystemItemBasicInfo child in children)
        {
            string userFileSystemItemPath = Path.Combine(UserFileSystemPath, child.Name);

            // Create ETags.
            // ETags must correspond with a server file/folder, NOT with a client placeholder. 
            // It should NOT be moved/deleted/updated when a placeholder in the user file system is moved/deleted/updated.
            // It should be moved/deleted when a file/folder in the remote storage is moved/deleted.
            ETag.SetETagAsync(userFileSystemItemPath, child.ETag);

            // Set the lock icon and read-only attribute, to indicate that the item is locked by another user.
            new UserFileSystemRawItem(userFileSystemItemPath).SetLockedByAnotherUserAsync(child.LockedByAnotherUser);
        }
    }
}

public class VirtualFolder : VirtualFileSystemItem, IFolder
{
    public VirtualFolder(string path, ILogger logger) : base(path, logger)
    {

    }

    public async Task CreateFileAsync(IFileMetadata fileMetadata, Stream content = null)
    {
        Logger.LogMessage($"{nameof(IFolder)}.{nameof(CreateFileAsync)}()", Path.Combine(UserFileSystemPath, fileMetadata.Name));

        FileInfo remoteStorageItem = new FileInfo(Path.Combine(RemoteStoragePath, fileMetadata.Name));

        // Upload remote storage file content.
        await using (FileStream remoteStorageStream = remoteStorageItem.Open(FileMode.CreateNew, FileAccess.Write, FileShare.Delete))
        {
            if (content != null)
            {
                await content.CopyToAsync(remoteStorageStream);
                remoteStorageStream.SetLength(content.Length);
            }
        }

        // Update remote storage file metadata.
        remoteStorageItem.Attributes = fileMetadata.Attributes;
        remoteStorageItem.CreationTimeUtc = fileMetadata.CreationTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = fileMetadata.LastWriteTime.UtcDateTime;
        remoteStorageItem.LastAccessTimeUtc = fileMetadata.LastAccessTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = fileMetadata.LastWriteTime.UtcDateTime;
    }

    public async Task CreateFolderAsync(IFolderMetadata folderMetadata)
    {
        Logger.LogMessage($"{nameof(IFolder)}.{nameof(CreateFolderAsync)}()", Path.Combine(UserFileSystemPath, folderMetadata.Name));

        DirectoryInfo remoteStorageItem = new DirectoryInfo(Path.Combine(RemoteStoragePath, folderMetadata.Name));
        remoteStorageItem.Create();

        // Update remote storage folder metadata.
        remoteStorageItem.Attributes = folderMetadata.Attributes;
        remoteStorageItem.CreationTimeUtc = folderMetadata.CreationTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = folderMetadata.LastWriteTime.UtcDateTime;
        remoteStorageItem.LastAccessTimeUtc = folderMetadata.LastAccessTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = folderMetadata.LastWriteTime.UtcDateTime;
    }

    public async Task GetChildrenAsync(string pattern, IOperationContext operationContext, IFolderListingResultContext resultContext)
    {
        // This method has a 60 sec timeout. 
        // To process longer requests and reset the timout timer call one of the following:
        // - resultContext.ReturnChildren() method.
        // - resultContext.ReportProgress() method.

        Logger.LogMessage($"{nameof(IFolder)}.{nameof(GetChildrenAsync)}({pattern})", UserFileSystemPath);

        IEnumerable<FileSystemInfo> remoteStorageChildren = new DirectoryInfo(RemoteStoragePath).EnumerateFileSystemInfos(pattern);

        List<IFileSystemItemMetadata> userFileSystemChildren = new List<IFileSystemItemMetadata>();
        foreach (FileSystemInfo remoteStorageItem in remoteStorageChildren)
        {
            IFileSystemItemMetadata itemInfo = Mapping.GetUserFileSysteItemMetadata(remoteStorageItem);
            userFileSystemChildren.Add(itemInfo);

            string userFileSystemItemPath = Path.Combine(UserFileSystemPath, itemInfo.Name);

            // Filtering existing files/folders. This is only required to avoid extra errors in the log.
            if (!FsPath.Exists(userFileSystemItemPath))
            {
                Logger.LogMessage("Creating", userFileSystemItemPath);
                userFileSystemChildren.Add(itemInfo);
            }
        }

        // To signal that the children enumeration is completed 
        // always call ReturnChildren(), even if the folder is empty.
        resultContext.ReturnChildren(userFileSystemChildren.ToArray(), userFileSystemChildren.Count());
    }

    public async Task WriteAsync(IFolderMetadata folderMetadata)
    {
        Logger.LogMessage($"{nameof(IFolder)}.{nameof(WriteAsync)}()", UserFileSystemPath);

        DirectoryInfo remoteStorageItem = new DirectoryInfo(RemoteStoragePath);

        // Update remote storage folder metadata.
        remoteStorageItem.Attributes = folderMetadata.Attributes;
        remoteStorageItem.CreationTimeUtc = folderMetadata.CreationTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = folderMetadata.LastWriteTime.UtcDateTime;
        remoteStorageItem.LastAccessTimeUtc = folderMetadata.LastAccessTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = folderMetadata.LastWriteTime.UtcDateTime;
    }
}

public class VirtualFolder : VirtualFileSystemItem, IFolder
{
    public VirtualFolder(string path, ILogger logger) : base(path, logger)
    {

    }

    public async Task<string> CreateFileAsync(IFileMetadata fileMetadata, Stream content = null)
    {
        Logger.LogMessage($"{nameof(IFolder)}.{nameof(CreateFileAsync)}()", Path.Combine(UserFileSystemPath, fileMetadata.Name));

        FileInfo remoteStorageItem = new FileInfo(Path.Combine(RemoteStoragePath, fileMetadata.Name));

        // Upload remote storage file content.
        await using (FileStream remoteStorageStream = remoteStorageItem.Open(FileMode.CreateNew, FileAccess.Write, FileShare.Delete))
        {
            if (content != null)
            {
                await content.CopyToAsync(remoteStorageStream);
                remoteStorageStream.SetLength(content.Length);
            }
        }

        // Update remote storage file metadata.
        remoteStorageItem.Attributes = fileMetadata.Attributes;
        remoteStorageItem.CreationTimeUtc = fileMetadata.CreationTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = fileMetadata.LastWriteTime.UtcDateTime;
        remoteStorageItem.LastAccessTimeUtc = fileMetadata.LastAccessTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = fileMetadata.LastWriteTime.UtcDateTime;

        // Return remote storage item ID.
        return remoteStorageItem.FullName; 
    }

    public async Task<string> CreateFolderAsync(IFolderMetadata folderMetadata)
    {
        Logger.LogMessage($"{nameof(IFolder)}.{nameof(CreateFolderAsync)}()", Path.Combine(UserFileSystemPath, folderMetadata.Name));

        DirectoryInfo remoteStorageItem = new DirectoryInfo(Path.Combine(RemoteStoragePath, folderMetadata.Name));
        remoteStorageItem.Create();

        // Update remote storage folder metadata.
        remoteStorageItem.Attributes = folderMetadata.Attributes;
        remoteStorageItem.CreationTimeUtc = folderMetadata.CreationTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = folderMetadata.LastWriteTime.UtcDateTime;
        remoteStorageItem.LastAccessTimeUtc = folderMetadata.LastAccessTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = folderMetadata.LastWriteTime.UtcDateTime;

        // Return remote storage item ID.
        return remoteStorageItem.FullName;
    }

    public async Task GetChildrenAsync(string pattern, IOperationContext operationContext, IFolderListingResultContext resultContext)
    {
        // This method has a 60 sec timeout. 
        // To process longer requests and reset the timout timer call one of the following:
        // - resultContext.ReturnChildren() method.
        // - resultContext.ReportProgress() method.

        Logger.LogMessage($"{nameof(IFolder)}.{nameof(GetChildrenAsync)}({pattern})", UserFileSystemPath);

        IEnumerable<FileSystemInfo> remoteStorageChildren = new DirectoryInfo(RemoteStoragePath).EnumerateFileSystemInfos(pattern);

        List<IFileSystemItemMetadata> userFileSystemChildren = new List<IFileSystemItemMetadata>();
        foreach (FileSystemInfo remoteStorageItem in remoteStorageChildren)
        {
            IFileSystemItemMetadata itemInfo = Mapping.GetUserFileSysteItemMetadata(remoteStorageItem);

            string userFileSystemItemPath = Path.Combine(UserFileSystemPath, itemInfo.Name);

            // Filtering existing files/folders. This is only required to avoid extra errors in the log.
            if (!FsPath.Exists(userFileSystemItemPath))
            {
                Logger.LogMessage("Creating", userFileSystemItemPath);
                userFileSystemChildren.Add(itemInfo);
            }
        }

        // To signal that the children enumeration is completed 
        // always call ReturnChildren(), even if the folder is empty.
        resultContext.ReturnChildren(userFileSystemChildren.ToArray(), userFileSystemChildren.Count());
    }

    public async Task WriteAsync(IFolderMetadata folderMetadata)
    {
        Logger.LogMessage($"{nameof(IFolder)}.{nameof(WriteAsync)}()", UserFileSystemPath);

        DirectoryInfo remoteStorageItem = new DirectoryInfo(RemoteStoragePath);

        // Update remote storage folder metadata.
        remoteStorageItem.Attributes = folderMetadata.Attributes;
        remoteStorageItem.CreationTimeUtc = folderMetadata.CreationTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = folderMetadata.LastWriteTime.UtcDateTime;
        remoteStorageItem.LastAccessTimeUtc = folderMetadata.LastAccessTime.UtcDateTime;
        remoteStorageItem.LastWriteTimeUtc = folderMetadata.LastWriteTime.UtcDateTime;
    }
}