Improve the bandmap window

Remove the status bar and the band name, add the 75 and 150 kHz spans,
add buttons for the callsign size (saved in the settings), draw the scale
in the form's text colour so it shows in the dark theme, mark the carrier
on the VFO bar and place a sideband bar on its side of the carrier, and
show who spotted a station, when, and the comment when the pointer is on it.

Co-Authored-By: Claude Sonnet 5.5 <noreply@anthropic.com>

src/Nonemm.App/Windows/BandmapView.cs

@@ -19,10 +19,16 @@ public sealed class BandmapView : Control
     private const double ScaleX = 52;
     private const double LabelX = 96;
     private const double TickLength = 6;
-    private const double LabelHeight = 15;
-    private const double TextSize = 12;
+    private const double ScaleTextSize = 12;
+
+    /// Callsigns are drawn this much taller than their text, so the lines of
+    /// two neighbours do not touch.
+    private const double LabelPadding = 3;
     private const double VfoWidth = 4;
 
+    /// How far the carrier tick reaches past each side of the bar.
+    private const double CarrierOverhang = 3;
+
     /// The scale stops short of the top and bottom edges so the first and last
     /// frequency numbers are not cut in half.
     private const double Inset = 9;
@@ -46,6 +52,11 @@ public sealed class BandmapView : Control
 
     public IReadOnlyList<Spot> Spots { get; set; } = [];
 
+    /// The height of the callsigns, in points.
+    public double TextSize { get; set; } = 12;
+
+    private double LabelHeight => TextSize + LabelPadding;
+
     public IReadOnlyList<VfoMarker> Vfos { get; set; } = [];
 
     public Frequency Low { get; set; } = Bands.Band20M.Low;
@@ -121,7 +132,7 @@ public sealed class BandmapView : Control
 
     private void DrawScale(DrawingContext context, IBrush ink)
     {
-        Pen line = new(Opaque(ink, 0.5), 1);
+        Pen line = new(Opaque(ink, 0.7), 1);
         context.DrawLine(line, new Point(ScaleX, Inset), new Point(ScaleX, Inset + scale.Height));
         foreach (Frequency tick in BandmapLayout.Ticks(scale, TickStep))
         {
@@ -129,7 +140,8 @@ public sealed class BandmapView : Control
             context.DrawLine(line, new Point(ScaleX - TickLength, y), new Point(ScaleX, y));
             FormattedText text = Text(
                 tick.Kilohertz.ToString("0.#", CultureInfo.InvariantCulture),
-                Opaque(ink, 0.6));
+                Opaque(ink, 0.8),
+                ScaleTextSize);
             context.DrawText(text, new Point(ScaleX - TickLength - 4 - text.Width, y - (text.Height / 2)));
         }
     }
@@ -142,9 +154,13 @@ public sealed class BandmapView : Control
             double bottom = scale.YFor(vfo.High) + Inset;
             // a narrow mode would be less than a pixel tall
             double height = Math.Max(3, bottom - top);
+            IBrush brush = BrushFor(vfo.Role);
+            context.FillRectangle(brush, new Rect(ScaleX - (VfoWidth / 2), top, VfoWidth, height));
+            // the carrier, which is not in the middle of a sideband
+            double carrier = Math.Round(scale.YFor(vfo.Carrier) + Inset);
             context.FillRectangle(
-                BrushFor(vfo.Role),
-                new Rect(ScaleX - (VfoWidth / 2), top, VfoWidth, height));
+                brush,
+                new Rect(ScaleX - (VfoWidth / 2) - CarrierOverhang, carrier - 1, VfoWidth + (2 * CarrierOverhang), 2));
         }
     }
 
@@ -152,10 +168,12 @@ public sealed class BandmapView : Control
     {
         IBrush colour = ColourOf(label.Spot);
         context.DrawLine(
-            new Pen(Opaque(ink, 0.35), 1),
+            new Pen(Opaque(ink, 0.55), 1),
             new Point(ScaleX + 2, label.MarkY),
             new Point(LabelX - 2, label.LabelY + (LabelHeight / 2)));
-        context.DrawText(Text(label.Spot.Call.Text, colour), new Point(LabelX, label.LabelY));
+        context.DrawText(
+            Text(label.Spot.Call.Text, colour, TextSize),
+            new Point(LabelX, label.LabelY + (LabelPadding / 2)));
     }
 
     protected override void OnPointerWheelChanged(PointerWheelEventArgs e)
@@ -168,26 +186,37 @@ public sealed class BandmapView : Control
         }
     }
 
+    private BandmapLabel? LabelAt(Point at) =>
+        at.X < LabelX
+            ? null
+            : placed.FirstOrDefault(l => at.Y >= l.LabelY && at.Y <= l.LabelY + LabelHeight);
+
+    protected override void OnPointerMoved(PointerEventArgs e)
+    {
+        base.OnPointerMoved(e);
+        ToolTip.SetTip(
+            this,
+            LabelAt(e.GetPosition(this)) is { } label ? SpotDescription.Of(label.Spot) : null);
+    }
+
     protected override void OnPointerPressed(PointerPressedEventArgs e)
     {
         base.OnPointerPressed(e);
         Point at = e.GetPosition(this);
-        foreach (BandmapLabel label in placed)
+        if (LabelAt(at) is { } label)
         {
-            if (at.X >= LabelX && at.Y >= label.LabelY && at.Y <= label.LabelY + LabelHeight)
-            {
-                SpotPicked?.Invoke(this, label.Spot);
-                return;
-            }
+            SpotPicked?.Invoke(this, label.Spot);
+            return;
         }
         FrequencyPicked?.Invoke(this, scale.At(at.Y - Inset));
     }
 
-    private FormattedText Text(string text, IBrush brush) =>
-        new(text, CultureInfo.InvariantCulture, FlowDirection.LeftToRight, typeface, TextSize, brush);
+    private FormattedText Text(string text, IBrush brush, double size) =>
+        new(text, CultureInfo.InvariantCulture, FlowDirection.LeftToRight, typeface, size, brush);
 
+    /// The form's text colour, which the theme sets in both light and dark.
     private IBrush Foreground() =>
-        this.FindResource("SystemControlForegroundBaseHighBrush") as IBrush ?? Brushes.Gray;
+        this.FindResource("FormForeground") as IBrush ?? Brushes.Gray;
 
     private static IBrush Opaque(IBrush ink, double opacity) =>
         ink is ISolidColorBrush solid