gistfile1.txt

import 'dart:io';
import 'dart:math';

class FileSaveDirectory {
  FileSaveDirectory(this.parentDirectoryFuture);

  Directory? _saveDirectory;
  final Future<Directory> parentDirectoryFuture;
  bool get isExists => _saveDirectory?.existsSync() ?? false;
  String get path => _saveDirectory!.path;
  Directory? get directory => _saveDirectory;

  /// Create directory in device temporary directory with a given [subDirName] for
  /// video or captured images (see [remove]).
  Future<void> initialize(String subDirName,{bool clear = false}) async {
    _saveDirectory =
        Directory((await parentDirectoryFuture).path + '/$subDirName/');

    if(clear){
      await remove();
    }

    if (!_saveDirectory!.existsSync()) {
      await _saveDirectory!.create(recursive: true);
    }
  }

  /// Removes created subdirectory (see [initialize]).
  Future<void> remove() async {
    if (_saveDirectory != null && _saveDirectory!.existsSync()) {
      _saveDirectory!.deleteSync(recursive: true);
    }
  }

  /// Generate full file path with given file [fileExtension]
  /// (see [initialize] and [remove]).
  String generateFilePath(String fileExtension,{String? name}) {
    name = name ?? Random()
        .nextDouble()
        .toString()
        .replaceAll(',', '')
        .replaceAll('.', '');

    return _saveDirectory!.path + name + fileExtension;
  }

}


class EventStore {
  late final FileSaveDirectory _fileSaveDirectory =
      FileSaveDirectory(getTemporaryDirectory());

  Future<void> storeEvent(
      String legitimationId, EventReport eventReport) async {
    if (_fileSaveDirectory.directory == null) {
      await _fileSaveDirectory.initialize('events');
    }

    final file = File(_createFileName(legitimationId));
    final exists = file.existsSync();

    if (!exists) {
      await _fileSaveDirectory.initialize('events', clear: true);
      file.createSync();
    }

    await file.writeAsString(jsonEncode(eventReport.toJsonMap()) + "%%",
        mode: FileMode.append, flush: true);
  }

  Future<List<Map<String,dynamic>>> fetchEventsByLegitimationId(
      String legitimationId) async {
    final file = File(_createFileName(legitimationId));
    final exists = file.existsSync();
    if (!exists) {
      return [];
    }
    final jsonObjects = file.readAsStringSync().split('%%');
    if (jsonObjects.lastOrNull == '') {
      jsonObjects.removeLast();
    }
    final events = <Map<String,dynamic>> [
      for (final json in jsonObjects) jsonDecode(json) as Map<String,dynamic>
    ];
    return events;
  }

  Future<void> removeEventsByLegitimationId(String legitimationId) async {
    final file = File(_createFileName(legitimationId));
    file.deleteSync(recursive: true);
  }

  Future<List<String>> fetchEventFileNames() async {
    if(!_fileSaveDirectory.isExists){
      return [];
    }
    final directory = Directory(_fileSaveDirectory.path);
    return directory.listSync().map((e) => e.path.split('/').last).toList();
  }

  String _createFileName(String legitimationId) =>
      '${_fileSaveDirectory.path}/$legitimationId';
}