private async Task Upload()
        {
            IRemoteResource target;
            C4CHttpClient   cloudClient;

            bool   silentOptionSet         = false;
            bool   overrideDefaultTypeCode = false;
            string typeCode = "10001";

            List <string> optionsAndParameter = new List <string>(this.args);

            string targetArg = optionsAndParameter[optionsAndParameter.Count - 1];

            optionsAndParameter.RemoveAt(optionsAndParameter.Count - 1);            // Remove Target
            optionsAndParameter.RemoveAt(0);                                        // Remove "upload"

            TargetDescription targetDescription = new TargetDescription(targetArg); // parseTargetDescription(TargetArg);

            cloudClient = CreateCloudClient(targetDescription);

            List <string> files2Upload = new List <string>();

            foreach (var element in optionsAndParameter)
            {
                if (overrideDefaultTypeCode)
                {
                    typeCode = element;
                    overrideDefaultTypeCode = false;

                    continue;
                }

                if (element == "-s")
                {
                    silentOptionSet = true;

                    continue;
                }

                if (element == "-C")
                {
                    overrideDefaultTypeCode = true;

                    continue;
                }

                files2Upload.AddRange(GetFiles(element));
            }

            if (files2Upload.Count == 0)
            {
                // ToDo: Error?
            }

            files2Upload = files2Upload.Distinct().ToList();

            if (targetDescription.Collection == string.Empty || targetDescription.Identifier == string.Empty)
            {
                throw new Exception("Target collection or identifier not set.");
            }

            if (targetDescription.Identifier[0] == '#')
            {
                target = TargetFactory.CreateC4CTarget(targetDescription.Collection, targetDescription.Identifier.Substring(1), cloudClient, typeCode);
            }
            else
            {
                target = TargetFactory.CreateC4CTarget(targetDescription.Collection, targetDescription.Identifier, typeCode);
            }

            foreach (string filePath in files2Upload)
            {
                var uploadTask = await cloudClient.UploadFileAsync(new FileSystemResource(filePath), target);

                if (!silentOptionSet)
                {
                    uploadTask.PrintMetdata();

                    Console.WriteLine();
                }
            }
        }
        private async Task List()
        {
            IClient cloudClient;

            IRemoteResource directory2Read;

            List <string> optionsAndParameter = new List <string>(this.args);

            string targetArg = optionsAndParameter[optionsAndParameter.Count - 1];

            optionsAndParameter.RemoveAt(optionsAndParameter.Count - 1); // Remove Target
            optionsAndParameter.RemoveAt(0);                             // Remove "list"

            TargetDescription targetDescription = new TargetDescription(targetArg);

            IOutputOptions outputOptions = new OutputOptions();

            string filterPattern    = string.Empty;
            bool   filterByWildcard = false;
            bool   filterByRegex    = false;

            foreach (var element in optionsAndParameter)
            {
                if ((filterByWildcard || filterByRegex) && filterPattern == string.Empty)
                {
                    filterPattern = element;
                    continue;
                }

                if (element == "-r") // reverse sort order
                {
                    outputOptions.SortDirection = ListSortDirection.Descending;
                    continue;
                }

                if (element == "-X") // sort by file extension
                {
                    outputOptions.SortAttribute = "FilenameExtension";
                    continue;
                }

                if (element == "-M") // sort by Mime type
                {
                    outputOptions.SortAttribute = "MimeType";
                    continue;
                }

                if (element == "-U") // sort by UUID
                {
                    outputOptions.SortAttribute = "UUID";
                    continue;
                }

                if (element == "-P") // pattern
                {
                    filterByWildcard = true;
                }

                if (element == "-R") // REGEX
                {
                    filterByRegex = true;
                }
            }

            cloudClient = CreateCloudClient(targetDescription);

            if (targetDescription.Collection == string.Empty || targetDescription.Identifier == string.Empty)
            {
                throw new Exception("Target collection or identifier not set.");
            }

            if (targetDescription.Identifier[0] == '#')
            {
                directory2Read = TargetFactory.CreateC4CTarget(targetDescription.Collection, targetDescription.Identifier.Substring(1), (C4CHttpClient)cloudClient);
            }
            else
            {
                directory2Read = TargetFactory.CreateC4CTarget(targetDescription.Collection, targetDescription.Identifier);
            }

            var fileListing = await cloudClient.GetFileListingAsync(directory2Read);

            if (filterByWildcard)
            {
                fileListing.RemoveNotMatchingWildcard(filterPattern);
            }

            if (filterByRegex)
            {
                fileListing.RemoveNotMatchingRegex(filterPattern);
            }

            fileListing.ListFiles(outputOptions);
        }
        private async Task Download()
        {
            C4CHttpClient cloudClient;
            List <string> optionsAndParameter = new List <string>(this.args);

            IRemoteResource directory2Read;

            string filterPattern    = string.Empty;
            bool   filterByWildcard = false;
            bool   filterByRegex    = false;

            bool overrideDefaultParallelism = false;
            int  maxParallelism             = 4;

            string targetArg = optionsAndParameter[optionsAndParameter.Count - 1];

            optionsAndParameter.RemoveAt(optionsAndParameter.Count - 1); //Remove Target
            optionsAndParameter.RemoveAt(0);                             // Remove "download"

            TargetDescription targetDescription = new TargetDescription(targetArg);

            foreach (var element in optionsAndParameter)
            {
                if ((filterByWildcard || filterByRegex) && filterPattern == string.Empty)
                {
                    filterPattern = element;
                    continue;
                }

                if (overrideDefaultParallelism)
                {
                    maxParallelism             = int.Parse(element);
                    overrideDefaultParallelism = false;
                }

                if (element == "-P") // pattern
                {
                    filterByWildcard = true;
                }

                if (element == "-R") // REGEX
                {
                    filterByRegex = true;
                }

                if (element == "-T") // Max number of download threads
                {
                    overrideDefaultParallelism = true;
                }
            }

            cloudClient = CreateCloudClient(targetDescription);

            if (targetDescription.Collection == string.Empty || targetDescription.Identifier == string.Empty)
            {
                throw new Exception("Target collection or identifier not set.");
            }

            if (targetDescription.Identifier[0] == '#')
            {
                directory2Read = TargetFactory.CreateC4CTarget(targetDescription.Collection, targetDescription.Identifier.Substring(1), cloudClient);
            }
            else
            {
                directory2Read = TargetFactory.CreateC4CTarget(targetDescription.Collection, targetDescription.Identifier);
            }

            var fileListing = await cloudClient.GetFileListingAsync(directory2Read);

            if (filterByWildcard)
            {
                fileListing.RemoveNotMatchingWildcard(filterPattern);
            }

            if (filterByRegex)
            {
                fileListing.RemoveNotMatchingRegex(filterPattern);
            }

            // Links cannot be downloaded and dont have a DownloadURI set
            fileListing.RemoveEmptyURIs();

            var downloadTasks = new List <Task>();
            var sSlim         = new SemaphoreSlim(initialCount: maxParallelism);

            foreach (var fileMetadata in fileListing)
            {
                await sSlim.WaitAsync();

                downloadTasks.Add(
                    Task.Run(async() =>
                {
                    try
                    {
                        await cloudClient.DownloadFileAsync(fileMetadata, new FileSystemResource(fileMetadata.Filename));
                        Console.WriteLine(fileMetadata.Filename);
                    }
                    finally
                    {
                        sSlim.Release();
                    }
                }));
            }

            await Task.WhenAll(downloadTasks);
        }