Wino-Mail/Wino.Calendar/Controls/DayColumnControl.cs

using System;
using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Wino.Core.Domain.Models.Calendar;

namespace Wino.Calendar.Controls
{
    public class DayColumnControl : Control
    {
        private const string PART_HeaderDateDayText = nameof(PART_HeaderDateDayText);
        private const string PART_IsTodayBorder = nameof(PART_IsTodayBorder);
        private const string PART_ColumnHeaderText = nameof(PART_ColumnHeaderText);

        private const string TodayState = nameof(TodayState);
        private const string NotTodayState = nameof(NotTodayState);

        private TextBlock HeaderDateDayText;
        private TextBlock ColumnHeaderText;
        private Border IsTodayBorder;

        public CalendarDayModel DayModel
        {
            get { return (CalendarDayModel)GetValue(DayModelProperty); }
            set { SetValue(DayModelProperty, value); }
        }

        public static readonly DependencyProperty DayModelProperty = DependencyProperty.Register(nameof(DayModel), typeof(CalendarDayModel), typeof(DayColumnControl), new PropertyMetadata(null, new PropertyChangedCallback(OnRenderingPropertiesChanged)));

        public DayColumnControl()
        {
            DefaultStyleKey = typeof(DayColumnControl);
        }

        protected override void OnApplyTemplate()
        {
            base.OnApplyTemplate();

            HeaderDateDayText = GetTemplateChild(PART_HeaderDateDayText) as TextBlock;
            ColumnHeaderText = GetTemplateChild(PART_ColumnHeaderText) as TextBlock;
            IsTodayBorder = GetTemplateChild(PART_IsTodayBorder) as Border;

            UpdateValues();
        }

        private static void OnRenderingPropertiesChanged(DependencyObject control, DependencyPropertyChangedEventArgs e)
        {
            if (control is DayColumnControl columnControl)
            {
                columnControl.UpdateValues();
            }
        }

        private void UpdateValues()
        {
            if (HeaderDateDayText == null || ColumnHeaderText == null || IsTodayBorder == null || DayModel == null) return;

            HeaderDateDayText.Text = DayModel.RepresentingDate.Day.ToString();
            ColumnHeaderText.Text = DayModel.RepresentingDate.ToString("dddd", DayModel.CalendarRenderOptions.CalendarSettings.CultureInfo);

            bool isToday = DayModel.RepresentingDate.Date == DateTime.Now.Date;

            VisualStateManager.GoToState(this, isToday ? TodayState : NotTodayState, false);
        }
    }
}