Flutter 文件类型常量

class FileExtension {
  static const String PDF = 'pdf';
  static const String DOC = 'doc';
  static const String DOCX = 'docx';
  static const String XLS = 'xls';
  static const String XLSX = 'xlsx';
  static const String PPT = 'ppt';
  static const String PPTX = 'pptx';
  static const String TXT = 'txt';
  static const String RTF = 'rtf';

  // file extension icon constants
  static const String FILE_EXTENSION_PDF_ICON =
      'assets/icons/file_extension/pdf.png';
  static const String FILE_EXTENSION_DOC_ICON =
      'assets/icons/file_extension/doc.png';
  static const String FILE_EXTENSION_DOCX_ICON =
      'assets/icons/file_extension/docx.png';
  static const String FILE_EXTENSION_XLS_ICON =
      'assets/icons/file_extension/xls.png';
  static const String FILE_EXTENSION_XLSX_ICON =
      'assets/icons/file_extension/xlsx.png';
  static const String FILE_EXTENSION_PPT_ICON =
      'assets/icons/file_extension/ppt.png';
  static const String FILE_EXTENSION_PPTX_ICON =
      'assets/icons/file_extension/pptx.png';
  static const String FILE_EXTENSION_TXT_ICON =
      'assets/icons/file_extension/txt.png';
  static const String FILE_EXTENSION_RTF_ICON =
      'assets/icons/file_extension/rtf.png';

  static const List<String> SUPPORTED_FILE_EXTENSIONS = [
    PDF,
    DOC,
    DOCX,
    XLS,
    XLSX,
    PPT,
    PPTX,
    TXT,
    RTF,
  ];

  static const Map<String, String> FILE_EXTENSION_ICON_MAP = {
    PDF: FILE_EXTENSION_PDF_ICON,
    DOC: FILE_EXTENSION_DOC_ICON,
    DOCX: FILE_EXTENSION_DOCX_ICON,
    XLS: FILE_EXTENSION_XLS_ICON,
    XLSX: FILE_EXTENSION_XLSX_ICON,
    PPT: FILE_EXTENSION_PPT_ICON,
    PPTX: FILE_EXTENSION_PPTX_ICON,
    TXT: FILE_EXTENSION_TXT_ICON,
    RTF: FILE_EXTENSION_RTF_ICON,
  };

  // get file extension icon
  static String? getFileExtensionIcon(String fileExtension) {
    if (FILE_EXTENSION_ICON_MAP.containsKey(fileExtension)) {
      return FILE_EXTENSION_ICON_MAP[fileExtension];
    }
    return '';
  }
}