local_data_source.dart

import 'dart:convert';

import 'package:hive/hive.dart' show Box;

abstract class ILocalDataSource {
  SomeModel getSomeModel();
  Future<void> saveSomeModel(SomeModel model);
}

class LocalDataSource implements ILocalDataSource {
	LocalDataSource({required Box box}) : _box = box;

  final Box _box;

  @override
  SomeModel getSomeModel() {
    final encodedJson = _box.get('model_key');

    if (encodedJson != null) {
      final model = SomeModel.fromJson(json.decode(jsonStr));
      return model;
    } else {
      throw CacheException();
    }
  }

	@override
  Future<void> saveSomeModel(SomeModel model) async {
    await _box.put('model_key', json.encode(model.toJson()));
  }
}