Ground work for Wino Calendar. (#475)

Wino Calendar abstractions.

Wino.Calendar/Controls/CalendarDayItemsControl.cs

@@ -0,0 +1,132 @@
+using System.Collections.ObjectModel;
+using System.Collections.Specialized;
+using System.Linq;
+using Windows.UI.Xaml;
+using Windows.UI.Xaml.Controls;
+using Wino.Core.Domain.Interfaces;
+using Wino.Core.Domain.Models.Calendar;
+
+namespace Wino.Calendar.Controls
+{
+    public class CalendarDayItemsControl : Control
+    {
+        private const string PART_CalendarPanel = nameof(PART_CalendarPanel);
+
+        private WinoCalendarPanel CalendarPanel;
+
+        public CalendarDayModel DayModel
+        {
+            get { return (CalendarDayModel)GetValue(DayModelProperty); }
+            set { SetValue(DayModelProperty, value); }
+        }
+
+
+        public static readonly DependencyProperty DayModelProperty = DependencyProperty.Register(nameof(DayModel), typeof(CalendarDayModel), typeof(CalendarDayItemsControl), new PropertyMetadata(null, new PropertyChangedCallback(OnRepresentingDateChanged)));
+
+        private static void OnRepresentingDateChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
+        {
+            if (d is CalendarDayItemsControl control)
+            {
+                if (e.OldValue != null && e.OldValue is CalendarDayModel oldCalendarDayModel)
+                {
+                    control.DetachCollection(oldCalendarDayModel.Events);
+                }
+
+                if (e.NewValue != null && e.NewValue is CalendarDayModel newCalendarDayModel)
+                {
+                    control.AttachCollection(newCalendarDayModel.Events);
+                }
+
+                control.ResetItems();
+                control.RenderEvents();
+            }
+        }
+
+        public CalendarDayItemsControl()
+        {
+            DefaultStyleKey = typeof(CalendarDayItemsControl);
+        }
+
+        protected override void OnApplyTemplate()
+        {
+            base.OnApplyTemplate();
+
+            CalendarPanel = GetTemplateChild(PART_CalendarPanel) as WinoCalendarPanel;
+
+            RenderEvents();
+        }
+
+        private void ResetItems()
+        {
+            if (CalendarPanel == null) return;
+
+            CalendarPanel.Children.Clear();
+        }
+
+        private void RenderEvents()
+        {
+            if (CalendarPanel == null || CalendarPanel.DayModel == null) return;
+
+            RenderCalendarItems();
+        }
+
+        private void AttachCollection(ObservableCollection<ICalendarItem> newCollection)
+            => newCollection.CollectionChanged += CalendarItemsChanged;
+
+        private void DetachCollection(ObservableCollection<ICalendarItem> oldCollection)
+            => oldCollection.CollectionChanged -= CalendarItemsChanged;
+
+        private void CalendarItemsChanged(object sender, NotifyCollectionChangedEventArgs e)
+        {
+            switch (e.Action)
+            {
+                case NotifyCollectionChangedAction.Add:
+                    foreach (ICalendarItem item in e.NewItems)
+                    {
+                        AddItem(item);
+                    }
+                    break;
+                case NotifyCollectionChangedAction.Remove:
+                    foreach (ICalendarItem item in e.OldItems)
+                    {
+                        var control = GetCalendarItemControl(item);
+                        if (control != null)
+                        {
+                            CalendarPanel.Children.Remove(control);
+                        }
+                    }
+                    break;
+                case NotifyCollectionChangedAction.Reset:
+                    ResetItems();
+                    break;
+                default:
+                    break;
+            }
+        }
+
+        private CalendarItemControl GetCalendarItemControl(ICalendarItem item)
+            => CalendarPanel.Children.Where(c => c is CalendarItemControl calendarItemControl && calendarItemControl.Item == item).FirstOrDefault() as CalendarItemControl;
+
+        private void RenderCalendarItems()
+        {
+            if (DayModel == null || DayModel.Events == null || DayModel.Events.Count == 0)
+            {
+                ResetItems();
+                return;
+            }
+
+            foreach (var item in DayModel.Events)
+            {
+                AddItem(item);
+            }
+        }
+
+        private void AddItem(ICalendarItem item)
+        {
+            CalendarPanel.Children.Add(new CalendarItemControl()
+            {
+                Item = item
+            });
+        }
+    }
+}