Implement an abstract RulesetSelector class

osu.Game/Rulesets/RulesetSelector.cs

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+// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
+// See the LICENCE file in the repository root for full licence text.
+
+using osu.Framework.Graphics.UserInterface;
+using osu.Framework.Bindables;
+using osu.Framework.Allocation;
+
+namespace osu.Game.Rulesets
+{
+    public abstract class RulesetSelector : TabControl<RulesetInfo>
+    {
+        protected RulesetStore AvaliableRulesets;
+        protected readonly Bindable<RulesetInfo> GlobalRuleset = new Bindable<RulesetInfo>();
+
+        protected override Dropdown<RulesetInfo> CreateDropdown() => null;
+
+        /// <summary>
+        /// Whether we want to change a global ruleset when local one is changed.
+        /// </summary>
+        protected virtual bool AllowGlobalRulesetChange => true;
+
+        /// <summary>
+        /// Whether we want to change a local ruleset when global one is changed.
+        /// /// </summary>
+        protected virtual bool AllowLocalRulesetChange => true;
+
+        [BackgroundDependencyLoader]
+        private void load(RulesetStore rulesets, Bindable<RulesetInfo> parentRuleset)
+        {
+            AvaliableRulesets = rulesets;
+            GlobalRuleset.BindTo(parentRuleset);
+
+            foreach (var r in rulesets.AvailableRulesets)
+            {
+                AddItem(r);
+            }
+
+            GlobalRuleset.BindValueChanged(globalRulesetChanged);
+            Current.BindValueChanged(OnLocalRulesetChanged);
+        }
+
+        private void globalRulesetChanged(ValueChangedEvent<RulesetInfo> e)
+        {
+            if (AllowLocalRulesetChange)
+            {
+                OnGlobalRulesetChanged(e);
+            }
+        }
+
+        protected virtual void OnGlobalRulesetChanged(ValueChangedEvent<RulesetInfo> e)
+        {
+            Current.Value = e.NewValue;
+        }
+
+        protected virtual void OnLocalRulesetChanged(ValueChangedEvent<RulesetInfo> e)
+        {
+            if (!GlobalRuleset.Disabled && AllowGlobalRulesetChange)
+            {
+                GlobalRuleset.Value = e.NewValue;
+            }
+        }
+    }
+}