Ground work for Wino Calendar. (#475)

Wino Calendar abstractions.

Wino.Calendar/Views/CalendarPage.xaml.cs

@@ -0,0 +1,77 @@
+using System;
+using CommunityToolkit.Mvvm.Messaging;
+using Microsoft.UI.Xaml.Controls;
+using Windows.UI.Xaml.Controls;
+using Wino.Calendar.Args;
+using Wino.Calendar.Views.Abstract;
+using Wino.Core.Domain.Models.Calendar;
+using Wino.Messaging.Client.Calendar;
+
+namespace Wino.Calendar.Views
+{
+    public sealed partial class CalendarPage : CalendarPageAbstract,
+        IRecipient<ScrollToDateMessage>,
+        IRecipient<GoNextDateRequestedMessage>,
+        IRecipient<GoPreviousDateRequestedMessage>
+    {
+        private DateTime? selectedDateTime;
+        public CalendarPage()
+        {
+            InitializeComponent();
+        }
+
+        public void Receive(ScrollToDateMessage message) => CalendarControl.NavigateToDay(message.Date);
+
+        public void Receive(GoNextDateRequestedMessage message) => CalendarControl.GoNextRange();
+
+        public void Receive(GoPreviousDateRequestedMessage message) => CalendarControl.GoPreviousRange();
+
+        private void CellSelected(object sender, TimelineCellSelectedArgs e)
+        {
+            selectedDateTime = e.ClickedDate;
+
+            TeachingTipPositionerGrid.Width = e.CellSize.Width;
+            TeachingTipPositionerGrid.Height = e.CellSize.Height;
+
+            Canvas.SetLeft(TeachingTipPositionerGrid, e.PositionerPoint.X);
+            Canvas.SetTop(TeachingTipPositionerGrid, e.PositionerPoint.Y);
+
+            WeakReferenceMessenger.Default.Send(new CalendarEventAdded(new CalendarItem(selectedDateTime.Value, default)));
+
+            //var t = new Flyout()
+            //{
+            //    Content = new TextBlock() { Text = "Create event" }
+            //};
+
+            //t.ShowAt(TeachingTipPositionerGrid, new FlyoutShowOptions()
+            //{
+            //    ShowMode = FlyoutShowMode.Transient,
+            //    Placement = FlyoutPlacementMode.Right
+            //});
+
+            NewEventTip.IsOpen = true;
+        }
+
+        private void CellUnselected(object sender, TimelineCellUnselectedArgs e)
+        {
+            NewEventTip.IsOpen = false;
+            selectedDateTime = null;
+        }
+
+        private void CreateEventTipClosed(TeachingTip sender, TeachingTipClosedEventArgs args)
+        {
+            // Reset the timeline selection when the tip is closed.
+            CalendarControl.ResetTimelineSelection();
+        }
+
+        private void AddEventClicked(object sender, Windows.UI.Xaml.RoutedEventArgs e)
+        {
+            if (selectedDateTime == null) return;
+
+            var eventEndDate = selectedDateTime.Value.Add(EventTimePicker.Time);
+
+            // Create the event.
+            WeakReferenceMessenger.Default.Send(new CalendarEventAdded(new CalendarItem(selectedDateTime.Value, eventEndDate)));
+        }
+    }
+}