private void RefreshMonthDaysForToDo(ToDoViewModel model)
        {
            DateTime date = model.WhenHappens;

            var monthToChange = Months.FirstOrDefault(
                m => m.Days.Any(x => x.CurrentDate.Year == date.Year &&
                                x.CurrentDate.Month == date.Month &&
                                x.CurrentDate.Day == date.Day));

            monthToChange?.RefreshDaysForActiveAndCompletedToDo(
                GetDaysWithToDoByDateAndStatus(monthToChange.CurrentDate, ConstantsHelper.Active),
                GetDaysWithToDoByDateAndStatus(monthToChange.CurrentDate, ConstantsHelper.Completed));
        }
        private void ChangeToDoStatus(ToDoViewModel model)
        {
            switch (model.Status)
            {
            case ToDoStatus.Active:
                model.Status = ToDoStatus.Completed;
                break;

            case ToDoStatus.Completed:
                model.Status = ToDoStatus.Active;
                break;
            }
            ToDoRepository.Save(model.ToToDoModel());
            _calendarViewModel.SelectDayCommand.Execute(_calendarViewModel.LastSelectedDate);
            RefreshMonthDaysForToDo(model);
        }