[add] Ahelp volume change

Content.Client/Options/UI/Tabs/AdminSettingsTab.xaml.cs

@@ -0,0 +1,50 @@
+using Content.Shared.CCVar;
+using Content.Shared.White;
+using Robust.Client.AutoGenerated;
+using Robust.Client.UserInterface;
+using Robust.Client.UserInterface.XAML;
+using Robust.Shared.Configuration;
+using Range = Robust.Client.UserInterface.Controls.Range;
+
+namespace Content.Client.Options.UI.Tabs;
+
+[GenerateTypedNameReferences]
+public sealed partial class AdminSettingsTab : Control
+{
+    [Dependency] private readonly IConfigurationManager _cfg = default!;
+
+    public AdminSettingsTab()
+    {
+        RobustXamlLoader.Load(this);
+        IoCManager.InjectDependencies(this);
+
+        LoadData();
+
+        AhelpSoundVolume.OnValueChanged += OnAhelpVolumeChanged;
+    }
+
+    protected override void Dispose(bool disposing)
+    {
+        AhelpSoundVolume.OnValueChanged -= OnAhelpVolumeChanged;
+        base.Dispose(disposing);
+    }
+
+    private void LoadData()
+    {
+        var bwoinkVolume = _cfg.GetCVar(WhiteCVars.BwoinkVolume);
+        AhelpSoundVolume.Value = bwoinkVolume;
+        AhelpSoundVolumeLabel.Text = ((int) bwoinkVolume).ToString();
+    }
+
+    private void OnAhelpVolumeChanged(Range newValue)
+    {
+        _cfg.SetCVar(WhiteCVars.BwoinkVolume, LV100ToDB(newValue.Value));
+        AhelpSoundVolumeLabel.Text = ((int)newValue.Value).ToString();
+    }
+
+    private float LV100ToDB(float lv100)
+    {
+        // Saving negative infinity doesn't work, so use -10000000 instead (MidiManager does it)
+        return MathF.Max(-10000000, MathF.Log(lv100 / 100, 10) * 10);
+    }
+}