0.1.5

LanMontainDesktop/Theme/AppThemePalette.cs

@@ -3,12 +3,29 @@ using Avalonia.Media;
 namespace LanMontainDesktop.Theme;
 
 public sealed record AppThemePalette(
+    Color Primary,
+    Color Secondary,
+    Color Accent,
+    Color OnAccent,
+    Color AccentLight1,
+    Color AccentLight2,
+    Color AccentLight3,
+    Color AccentDark1,
+    Color AccentDark2,
+    Color AccentDark3,
+    Color SurfaceBase,
+    Color SurfaceRaised,
+    Color SurfaceOverlay,
     Color TextPrimary,
     Color TextSecondary,
     Color TextMuted,
     Color TextAccent,
     Color NavText,
     Color NavSelectedText,
+    Color NavSelectionIndicator,
     Color NavItemBackground,
     Color NavItemHoverBackground,
-    Color NavItemSelectedBackground);
+    Color NavItemSelectedBackground,
+    Color ToggleOn,
+    Color ToggleOff,
+    Color ToggleBorder);

LanMontainDesktop/Theme/ColorMath.cs

@@ -0,0 +1,61 @@
+using System;
+using Avalonia.Media;
+
+namespace LanMontainDesktop.Theme;
+
+public static class ColorMath
+{
+    public static Color Blend(Color from, Color to, double ratio)
+    {
+        ratio = Math.Clamp(ratio, 0, 1);
+        var inverse = 1 - ratio;
+        var red = (byte)Math.Round((from.R * inverse) + (to.R * ratio));
+        var green = (byte)Math.Round((from.G * inverse) + (to.G * ratio));
+        var blue = (byte)Math.Round((from.B * inverse) + (to.B * ratio));
+        return Color.FromRgb(red, green, blue);
+    }
+
+    public static Color WithAlpha(Color color, byte alpha)
+    {
+        return Color.FromArgb(alpha, color.R, color.G, color.B);
+    }
+
+    public static Color EnsureContrast(Color preferred, Color background, double minRatio)
+    {
+        if (ContrastRatio(preferred, background) >= minRatio)
+        {
+            return preferred;
+        }
+
+        var white = Color.Parse("#FFFFFFFF");
+        var black = Color.Parse("#FF000000");
+        var whiteRatio = ContrastRatio(white, background);
+        var blackRatio = ContrastRatio(black, background);
+        return whiteRatio >= blackRatio ? white : black;
+    }
+
+    public static double ContrastRatio(Color first, Color second)
+    {
+        var firstLum = RelativeLuminance(first);
+        var secondLum = RelativeLuminance(second);
+        var lighter = Math.Max(firstLum, secondLum);
+        var darker = Math.Min(firstLum, secondLum);
+        return (lighter + 0.05) / (darker + 0.05);
+    }
+
+    private static double RelativeLuminance(Color color)
+    {
+        var red = ToLinear(color.R / 255d);
+        var green = ToLinear(color.G / 255d);
+        var blue = ToLinear(color.B / 255d);
+        return (0.2126 * red) + (0.7152 * green) + (0.0722 * blue);
+    }
+
+    private static double ToLinear(double value)
+    {
+        return value <= 0.04045
+            ? value / 12.92
+            : Math.Pow((value + 0.055) / 1.055, 2.4);
+    }
+}
+