From 9bf9a8c351ac533bbdd4b33a7f1659dd9544168f Mon Sep 17 00:00:00 2001
From: Dean Herbert <pe@ppy.sh>
Date: Wed, 13 Jan 2021 18:36:05 +0900
Subject: [PATCH] Remove Live<> wrapper until it is needed

---
 osu.Game/Database/Live.cs            | 104 ---------------------------
 osu.Game/Database/RealmExtensions.cs |  27 -------
 2 files changed, 131 deletions(-)
 delete mode 100644 osu.Game/Database/Live.cs

diff --git a/osu.Game/Database/Live.cs b/osu.Game/Database/Live.cs
deleted file mode 100644
index 49218ddd6e..0000000000
--- a/osu.Game/Database/Live.cs
+++ /dev/null
@@ -1,104 +0,0 @@
-// 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 System;
-using System.Threading;
-using Realms;
-
-#nullable enable
-
-namespace osu.Game.Database
-{
-    /// <summary>
-    /// Provides a method of passing realm live objects across threads in a safe fashion.
-    /// </summary>
-    /// <remarks>
-    /// To consume this as a live instance, the live object should be stored and accessed via <see cref="Get"/> each time.
-    /// To consume this as a detached instance, assign to a variable of type <typeparam ref="T"/>. The implicit conversion will handle detaching an instance.
-    /// </remarks>
-    /// <typeparam name="T">The underlying object type. Should be a <see cref="RealmObject"/> with a primary key provided via <see cref="IHasGuidPrimaryKey"/>.</typeparam>
-    public class Live<T> : IEquatable<Live<T>>, IHasGuidPrimaryKey
-        where T : RealmObject, IHasGuidPrimaryKey
-    {
-        /// <summary>
-        /// The primary key of the object.
-        /// </summary>
-        public Guid Guid { get; }
-
-        public string ID
-        {
-            get => Guid.ToString();
-            set => throw new NotImplementedException();
-        }
-
-        private readonly ThreadLocal<T> threadValues;
-
-        private readonly T original;
-
-        private readonly IRealmFactory contextFactory;
-
-        public Live(T item, IRealmFactory contextFactory)
-        {
-            this.contextFactory = contextFactory;
-
-            original = item;
-            Guid = item.Guid;
-
-            threadValues = new ThreadLocal<T>(getThreadLocalValue);
-
-            // the instance passed in may not be in a managed state.
-            // for now let's immediately retrieve a managed object on the current thread.
-            // in the future we may want to delay this until the first access (only populating the Guid at construction time).
-            if (!item.IsManaged)
-                original = Get();
-        }
-
-        private T getThreadLocalValue()
-        {
-            var context = contextFactory.Context;
-
-            // only use the original if no context is available or the source realm is the same.
-            if (context == null || original.Realm?.IsSameInstance(context) == true) return original;
-
-            return context.Find<T>(ID);
-        }
-
-        /// <summary>
-        /// Retrieve a live reference to the data.
-        /// </summary>
-        public T Get() => threadValues.Value;
-
-        /// <summary>
-        /// Retrieve a detached copy of the data.
-        /// </summary>
-        public T Detach() => Get().Detach();
-
-        /// <summary>
-        /// Wrap a property of this instance as its own live access object.
-        /// </summary>
-        /// <param name="lookup">The child to return.</param>
-        /// <typeparam name="TChild">The underlying child object type. Should be a <see cref="RealmObject"/> with a primary key provided via <see cref="IHasGuidPrimaryKey"/>.</typeparam>
-        /// <returns>A wrapped instance of the child.</returns>
-        public Live<TChild> WrapChild<TChild>(Func<T, TChild> lookup)
-            where TChild : RealmObject, IHasGuidPrimaryKey => new Live<TChild>(lookup(Get()), contextFactory);
-
-        /// <summary>
-        /// Perform a write operation on this live object.
-        /// </summary>
-        /// <param name="perform">The action to perform.</param>
-        public void PerformUpdate(Action<T> perform)
-        {
-            using (contextFactory.GetForWrite())
-                perform(Get());
-        }
-
-        public static implicit operator T?(Live<T>? wrapper)
-            => wrapper?.Detach() ?? null;
-
-        public static implicit operator Live<T>(T obj) => obj.WrapAsUnmanaged();
-
-        public bool Equals(Live<T>? other) => other != null && other.Guid == Guid;
-
-        public override string ToString() => Get().ToString();
-    }
-}
diff --git a/osu.Game/Database/RealmExtensions.cs b/osu.Game/Database/RealmExtensions.cs
index b25299bf23..07d397ca6c 100644
--- a/osu.Game/Database/RealmExtensions.cs
+++ b/osu.Game/Database/RealmExtensions.cs
@@ -1,7 +1,6 @@
 // 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 System;
 using System.Collections.Generic;
 using AutoMapper;
 using osu.Game.Beatmaps;
@@ -69,31 +68,5 @@ namespace osu.Game.Database
 
             return mapper.Map<T>(item);
         }
-
-        /// <summary>
-        /// Wrap a managed instance of a realm object in a <see cref="Live{T}"/>.
-        /// </summary>
-        /// <param name="item">The item to wrap.</param>
-        /// <param name="contextFactory">A factory to retrieve realm contexts from.</param>
-        /// <typeparam name="T">The type of object.</typeparam>
-        /// <returns>A wrapped instance of the provided item.</returns>
-        public static Live<T> Wrap<T>(this T item, IRealmFactory contextFactory)
-            where T : RealmObject, IHasGuidPrimaryKey => new Live<T>(item, contextFactory);
-
-        /// <summary>
-        /// Wrap an unmanaged instance of a realm object in a <see cref="Live{T}"/>.
-        /// </summary>
-        /// <param name="item">The item to wrap.</param>
-        /// <typeparam name="T">The type of object.</typeparam>
-        /// <returns>A wrapped instance of the provided item.</returns>
-        /// <exception cref="ArgumentException">Throws if the provided item is managed.</exception>
-        public static Live<T> WrapAsUnmanaged<T>(this T item)
-            where T : RealmObject, IHasGuidPrimaryKey
-        {
-            if (item.IsManaged)
-                throw new ArgumentException("Provided item must not be managed", nameof(item));
-
-            return new Live<T>(item, null);
-        }
     }
 }