Added dark mode 🦇

src/Artemis.UI/Utilities/ThemeWatcher.cs

@@ -0,0 +1,76 @@
+using System;
+using System.Globalization;
+using System.Management;
+using System.Security.Principal;
+using Artemis.UI.Events;
+using Microsoft.Win32;
+
+namespace Artemis.UI.Utilities
+{
+    public class ThemeWatcher
+    {
+        public ThemeWatcher()
+        {
+            WatchTheme();
+        }
+
+        public enum WindowsTheme
+        {
+            Light,
+            Dark
+        }
+
+        private const string RegistryKeyPath = @"Software\Microsoft\Windows\CurrentVersion\Themes\Personalize";
+
+        private const string RegistryValueName = "AppsUseLightTheme";
+
+        public void WatchTheme()
+        {
+            var currentUser = WindowsIdentity.GetCurrent();
+            var query = string.Format(
+                CultureInfo.InvariantCulture,
+                @"SELECT * FROM RegistryValueChangeEvent WHERE Hive = 'HKEY_USERS' AND KeyPath = '{0}\\{1}' AND ValueName = '{2}'",
+                currentUser.User.Value,
+                RegistryKeyPath.Replace(@"\", @"\\"),
+                RegistryValueName);
+
+            try
+            {
+                var watcher = new ManagementEventWatcher(query);
+                watcher.EventArrived += (sender, args) =>
+                {
+                    var newWindowsTheme = GetWindowsTheme();
+                    OnThemeChanged(new WindowsThemeEventArgs(newWindowsTheme));
+                };
+
+                // Start listening for events
+                watcher.Start();
+            }
+            catch (Exception)
+            {
+                // This can fail on Windows 7
+            }
+        }
+
+        public WindowsTheme GetWindowsTheme()
+        {
+            using (var key = Registry.CurrentUser.OpenSubKey(RegistryKeyPath))
+            {
+                var registryValueObject = key?.GetValue(RegistryValueName);
+                if (registryValueObject == null) return WindowsTheme.Light;
+
+                var registryValue = (int) registryValueObject;
+
+                return registryValue > 0 ? WindowsTheme.Light : WindowsTheme.Dark;
+            }
+        }
+
+        public event EventHandler<WindowsThemeEventArgs> ThemeChanged;
+
+
+        protected virtual void OnThemeChanged(WindowsThemeEventArgs e)
+        {
+            ThemeChanged?.Invoke(this, e);
+        }
+    }
+}