private void SelectFilePackages()
        {
            // TODO what is this?
            // temporarily change MULTI_ALT to BASE_ALT if a reference scenario ought to be defined - is changed back (and further treated) after user choice
//            bool refDef = template.TemplateType == EMS_TEMPLATE_TYPE.MULTI_ALT && template.FilePackageDefinition.SpecifyReference;
//            if (refDef) template.TemplateType = EMS_TEMPLATE_TYPE.BASE_ALT;

            if (templateInfo.templateType == HardDefinitions.TemplateType.Default ||
                (templateInfo.templateType == HardDefinitions.TemplateType.Multi))
            { // (simple) selection-dialog, which allows for selecting (one or more) files
                SelectFilesForm form = new SelectFilesForm(templateInfo);
                DialogResult = form.ShowDialog() == DialogResult.OK ? DialogResult.OK : DialogResult.Cancel;
                filePackages = form.filePackages;
            }
            else if (templateInfo.templateType == HardDefinitions.TemplateType.BaselineReform)
            { // dialog allowing to select one base and several alternatives
                SelectBaseAltsForm form = new SelectBaseAltsForm(templateInfo);
                DialogResult = form.ShowDialog() == DialogResult.OK ? DialogResult.OK : DialogResult.Cancel;
                filePackages = form.filePackages;
            }



            /*
             * if (refDef) // MULTI_ALT with a reference scenario: add the "base", i.e. the reference scenario, as the first alternative
             * {           // this is what the library needs to make EMS_Template.REFERENCE_ALT work
             *  foreach (EMS_FilePackageContent filePackage in filePackages)
             *  {
             *      filePackage.PathsAlt.Insert(0, filePackage.PathBase);
             *      filePackage.PathBase = string.Empty;
             *      template.TemplateType = EMS_TEMPLATE_TYPE.MULTI_ALT;
             *  }
             * }
             */
        }
        private void FillFileList(bool alt)
        {
            ListBox box         = alt ? listAlt : listBase;
            string  filePattern = "*.txt"; //TODO alt ? template.FilePackageDefinition.AltFileNamePattern : template.FilePackageDefinition.BaseFileNamePattern;
            string  path        = alt ? textAltPath.Text : textBasePath.Text;

            box.Items.Clear();
            if (Directory.Exists(path))
            {
                foreach (string filePath in Directory.GetFiles(path, filePattern))
                {
                    if (SelectFilesForm.isValidInput(filePath, templateInfo))
                    {
                        box.Items.Add((new FileInfo(filePath)).Name);
                    }
                }
            }
        }