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Nitrox.Launcher/Models/Converters/EqualityConverter.cs

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+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using Avalonia.Data.Converters;
+
+namespace Nitrox.Launcher.Models.Converters;
+
+/// <summary>
+///     Returns true if values are equal to each other.
+///     Or if value is singular, if parameter is equal to the value.
+/// </summary>
+public class EqualityConverter : Converter<EqualityConverter>, IMultiValueConverter
+{
+    public override object Convert(object value, Type targetType, object parameter, CultureInfo culture) => Equals(value, parameter);
+
+    public override object ConvertBack(object value, Type targetType, object parameter, CultureInfo culture) => throw new NotSupportedException();
+
+    public object Convert(IList<object> values, Type targetType, object parameter, CultureInfo culture)
+    {
+        foreach (object val1 in values)
+        {
+            foreach (object val2 in values)
+            {
+                if (ReferenceEquals(val1, val2))
+                {
+                    continue;
+                }
+                if (!Equals(val1, val2))
+                {
+                    return false;
+                }
+            }
+        }
+        return true;
+    }
+}