cpd_2022_zi/lib/service/date_service.dart

import 'package:smoke_cess_app/service/settings_service.dart';
import 'package:timezone/timezone.dart';

const int trainingTime = 40;

const weekDays = {
  "Montag": 1,
  "Dienstag": 2,
  "Mittwoch": 3,
  "Donnerstag": 4,
  "Freitag": 5,
  "Samstag": 6,
  "Sonntag": 7,
};

Future<List<TZDateTime>> getDatesforAll() async {
  List<TZDateTime> allDates = [];
  List<TZDateTime> moodDates = await getDatesforMood();
  List<TZDateTime> sleepDates = await getDatesforSleep();
  allDates.addAll(moodDates);
  allDates.addAll(sleepDates);
  return allDates;
}

Future<List<TZDateTime>> getDatesforMood() async {
  final List<String>? selectedDays = await getMoodQueryDaysCategories();
  final int? selectedHours = await getMoodQueryHours();
  final int? selectedMinutes = await getMoodQueryMinutes();
  return createTZDateTimes(selectedDays, selectedHours, selectedMinutes);
}

Future<List<TZDateTime>> getDatesforSleep() async {
  final List<String>? selectedDays = await getSleepQueryDaysCategories();
  final int? selectedHours = await getSleepQueryHours();
  final int? selectedMinutes = await getSleepQueryMinutes();
  return createTZDateTimes(selectedDays, selectedHours, selectedMinutes);
}

List<TZDateTime> createTZDateTimes(
    List<String>? selectedDays, int? selectedHours, int? selectedMinutes) {
  final List<TZDateTime> tzDateTimes = [];
  final DateTime now = DateTime.now();
  final Duration offset = now.timeZoneOffset;
  if (selectedDays == null ||
      selectedHours == null ||
      selectedMinutes == null) {
    return tzDateTimes;
  }
  final Iterable<int?> selectedDaysInt =
      selectedDays.map((day) => weekDays[day]);
  for (int i = 0; i < trainingTime; i++) {
    final DateTime date = DateTime(now.year, now.month, now.day, selectedHours,
            selectedMinutes, 0, 0, 0)
        .add(Duration(days: i));
    if (selectedDaysInt.contains(date.weekday) &&
        date.isAfter(DateTime.now())) {
      tzDateTimes.add(TZDateTime.local(date.year, date.month, date.day,
              selectedHours, selectedMinutes, 0, 0, 0)
          .subtract(offset));
    }
  }
  return tzDateTimes;
}