State Restoration support for Veggie Seasons app (#433)

veggieseasons/lib/data/app_state.dart

@@ -1,73 +0,0 @@
-// Copyright 2018 The Flutter team. All rights reserved.
-// Use of this source code is governed by a BSD-style license that can be
-// found in the LICENSE file.
-
-import 'package:flutter/foundation.dart';
-import 'package:veggieseasons/data/local_veggie_provider.dart';
-import 'package:veggieseasons/data/veggie.dart';
-
-class AppState extends ChangeNotifier {
-  final List<Veggie> _veggies;
-
-  AppState() : _veggies = LocalVeggieProvider.veggies;
-
-  List<Veggie> get allVeggies => List<Veggie>.from(_veggies);
-
-  List<Veggie> get availableVeggies {
-    var currentSeason = _getSeasonForDate(DateTime.now());
-    return _veggies.where((v) => v.seasons.contains(currentSeason)).toList();
-  }
-
-  List<Veggie> get favoriteVeggies =>
-      _veggies.where((v) => v.isFavorite).toList();
-
-  List<Veggie> get unavailableVeggies {
-    var currentSeason = _getSeasonForDate(DateTime.now());
-    return _veggies.where((v) => !v.seasons.contains(currentSeason)).toList();
-  }
-
-  Veggie getVeggie(int id) => _veggies.singleWhere((v) => v.id == id);
-
-  List<Veggie> searchVeggies(String terms) => _veggies
-      .where((v) => v.name.toLowerCase().contains(terms.toLowerCase()))
-      .toList();
-
-  void setFavorite(int id, bool isFavorite) {
-    var veggie = getVeggie(id);
-    veggie.isFavorite = isFavorite;
-    notifyListeners();
-  }
-
-  static Season _getSeasonForDate(DateTime date) {
-    // Technically the start and end dates of seasons can vary by a day or so,
-    // but this is close enough for produce.
-    switch (date.month) {
-      case 1:
-        return Season.winter;
-      case 2:
-        return Season.winter;
-      case 3:
-        return date.day < 21 ? Season.winter : Season.spring;
-      case 4:
-        return Season.spring;
-      case 5:
-        return Season.spring;
-      case 6:
-        return date.day < 21 ? Season.spring : Season.summer;
-      case 7:
-        return Season.summer;
-      case 8:
-        return Season.summer;
-      case 9:
-        return date.day < 22 ? Season.autumn : Season.winter;
-      case 10:
-        return Season.autumn;
-      case 11:
-        return Season.autumn;
-      case 12:
-        return date.day < 22 ? Season.autumn : Season.winter;
-      default:
-        throw ArgumentError('Can\'t return a season for month #${date.month}.');
-    }
-  }
-}