~repos /only-bible-app

import "dart:convert";
import "dart:io";

import "package:path_provider/path_provider.dart";
import "package:async_redux/async_redux.dart";
import "package:only_bible_app/store/app_state.dart";

class AppPersistor extends Persistor<AppState> {
  static const _fileName = "app_state.json";

  Future<File> get _file async {
    final dir = await getApplicationDocumentsDirectory();
    return File("${dir.path}/$_fileName");
  }

  @override
  Future<AppState?> readState() async {
    return null;
  }

  Future<Map<String, dynamic>?> readJson() async {
    try {
      final file = await _file;
      if (await file.exists()) {
        final contents = await file.readAsString();
        return jsonDecode(contents) as Map<String, dynamic>;
      }
    } catch (_) {}
    return null;
  }

  @override
  Future<void> deleteState() async {
    final file = await _file;
    if (await file.exists()) {
      await file.delete();
    }
  }

  @override
  Future<void> persistDifference({
    required AppState? lastPersistedState,
    required AppState newState,
  }) async {
    final file = await _file;
    final contents = jsonEncode(newState.toJson());
    await file.writeAsString(contents);
  }

  @override
  Duration? get throttle => const Duration(seconds: 1);
}