Merge pull request #10592 from barronpm/librarychangednotifier-cleanup

LibraryChangedNotifier Cleanup

1 files changed, 285 insertions, 383 deletions

diff --git a/Emby.Server.Implementations/EntryPoints/LibraryChangedNotifier.cs b/Emby.Server.Implementations/EntryPoints/LibraryChangedNotifier.cs
index be36bbd2c..a83d7a410 100644
--- a/Emby.Server.Implementations/EntryPoints/LibraryChangedNotifier.cs
+++ b/Emby.Server.Implementations/EntryPoints/LibraryChangedNotifier.cs
@@ -1,7 +1,3 @@
-#nullable disable
-
-#pragma warning disable CS1591
-
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
@@ -23,476 +19,382 @@ using MediaBrowser.Model.Entities;
 using MediaBrowser.Model.Session;
 using Microsoft.Extensions.Logging;
 
-namespace Emby.Server.Implementations.EntryPoints
+namespace Emby.Server.Implementations.EntryPoints;
+
+/// <summary>
+/// A <see cref="IServerEntryPoint"/> that notifies users when libraries are updated.
+/// </summary>
+public sealed class LibraryChangedNotifier : IServerEntryPoint
 {
-    public class LibraryChangedNotifier : IServerEntryPoint
+    private readonly ILibraryManager _libraryManager;
+    private readonly IServerConfigurationManager _configurationManager;
+    private readonly IProviderManager _providerManager;
+    private readonly ISessionManager _sessionManager;
+    private readonly IUserManager _userManager;
+    private readonly ILogger<LibraryChangedNotifier> _logger;
+
+    private readonly object _libraryChangedSyncLock = new();
+    private readonly List<Folder> _foldersAddedTo = new();
+    private readonly List<Folder> _foldersRemovedFrom = new();
+    private readonly List<BaseItem> _itemsAdded = new();
+    private readonly List<BaseItem> _itemsRemoved = new();
+    private readonly List<BaseItem> _itemsUpdated = new();
+    private readonly ConcurrentDictionary<Guid, DateTime> _lastProgressMessageTimes = new();
+
+    private Timer? _libraryUpdateTimer;
+
+    /// <summary>
+    /// Initializes a new instance of the <see cref="LibraryChangedNotifier"/> class.
+    /// </summary>
+    /// <param name="libraryManager">The <see cref="ILibraryManager"/>.</param>
+    /// <param name="configurationManager">The <see cref="IServerConfigurationManager"/>.</param>
+    /// <param name="sessionManager">The <see cref="ISessionManager"/>.</param>
+    /// <param name="userManager">The <see cref="IUserManager"/>.</param>
+    /// <param name="logger">The <see cref="ILogger"/>.</param>
+    /// <param name="providerManager">The <see cref="IProviderManager"/>.</param>
+    public LibraryChangedNotifier(
+        ILibraryManager libraryManager,
+        IServerConfigurationManager configurationManager,
+        ISessionManager sessionManager,
+        IUserManager userManager,
+        ILogger<LibraryChangedNotifier> logger,
+        IProviderManager providerManager)
     {
-        private readonly ILibraryManager _libraryManager;
-        private readonly IServerConfigurationManager _configurationManager;
-        private readonly IProviderManager _providerManager;
-        private readonly ISessionManager _sessionManager;
-        private readonly IUserManager _userManager;
-        private readonly ILogger<LibraryChangedNotifier> _logger;
-
-        /// <summary>
-        /// The library changed sync lock.
-        /// </summary>
-        private readonly object _libraryChangedSyncLock = new object();
-
-        private readonly List<Folder> _foldersAddedTo = new List<Folder>();
-        private readonly List<Folder> _foldersRemovedFrom = new List<Folder>();
-        private readonly List<BaseItem> _itemsAdded = new List<BaseItem>();
-        private readonly List<BaseItem> _itemsRemoved = new List<BaseItem>();
-        private readonly List<BaseItem> _itemsUpdated = new List<BaseItem>();
-        private readonly ConcurrentDictionary<Guid, DateTime> _lastProgressMessageTimes = new ConcurrentDictionary<Guid, DateTime>();
-
-        public LibraryChangedNotifier(
-            ILibraryManager libraryManager,
-            IServerConfigurationManager configurationManager,
-            ISessionManager sessionManager,
-            IUserManager userManager,
-            ILogger<LibraryChangedNotifier> logger,
-            IProviderManager providerManager)
-        {
-            _libraryManager = libraryManager;
-            _configurationManager = configurationManager;
-            _sessionManager = sessionManager;
-            _userManager = userManager;
-            _logger = logger;
-            _providerManager = providerManager;
-        }
+        _libraryManager = libraryManager;
+        _configurationManager = configurationManager;
+        _sessionManager = sessionManager;
+        _userManager = userManager;
+        _logger = logger;
+        _providerManager = providerManager;
+    }
 
-        /// <summary>
-        /// Gets or sets the library update timer.
-        /// </summary>
-        /// <value>The library update timer.</value>
-        private Timer LibraryUpdateTimer { get; set; }
+    /// <inheritdoc />
+    public Task RunAsync()
+    {
+        _libraryManager.ItemAdded += OnLibraryItemAdded;
+        _libraryManager.ItemUpdated += OnLibraryItemUpdated;
+        _libraryManager.ItemRemoved += OnLibraryItemRemoved;
 
-        public Task RunAsync()
-        {
-            _libraryManager.ItemAdded += OnLibraryItemAdded;
-            _libraryManager.ItemUpdated += OnLibraryItemUpdated;
-            _libraryManager.ItemRemoved += OnLibraryItemRemoved;
+        _providerManager.RefreshCompleted += OnProviderRefreshCompleted;
+        _providerManager.RefreshStarted += OnProviderRefreshStarted;
+        _providerManager.RefreshProgress += OnProviderRefreshProgress;
 
-            _providerManager.RefreshCompleted += OnProviderRefreshCompleted;
-            _providerManager.RefreshStarted += OnProviderRefreshStarted;
-            _providerManager.RefreshProgress += OnProviderRefreshProgress;
+        return Task.CompletedTask;
+    }
 
-            return Task.CompletedTask;
-        }
+    private void OnProviderRefreshProgress(object? sender, GenericEventArgs<Tuple<BaseItem, double>> e)
+    {
+        var item = e.Argument.Item1;
 
-        private void OnProviderRefreshProgress(object sender, GenericEventArgs<Tuple<BaseItem, double>> e)
+        if (!EnableRefreshMessage(item))
         {
-            var item = e.Argument.Item1;
+            return;
+        }
 
-            if (!EnableRefreshMessage(item))
+        var progress = e.Argument.Item2;
+
+        if (_lastProgressMessageTimes.TryGetValue(item.Id, out var lastMessageSendTime))
+        {
+            if (progress > 0 && progress < 100 && (DateTime.UtcNow - lastMessageSendTime).TotalMilliseconds < 1000)
             {
                 return;
             }
+        }
 
-            var progress = e.Argument.Item2;
+        _lastProgressMessageTimes.AddOrUpdate(item.Id, _ => DateTime.UtcNow, (_, _) => DateTime.UtcNow);
 
-            if (_lastProgressMessageTimes.TryGetValue(item.Id, out var lastMessageSendTime))
-            {
-                if (progress > 0 && progress < 100 && (DateTime.UtcNow - lastMessageSendTime).TotalMilliseconds < 1000)
-                {
-                    return;
-                }
-            }
+        var dict = new Dictionary<string, string>();
+        dict["ItemId"] = item.Id.ToString("N", CultureInfo.InvariantCulture);
+        dict["Progress"] = progress.ToString(CultureInfo.InvariantCulture);
 
-            _lastProgressMessageTimes.AddOrUpdate(item.Id, _ => DateTime.UtcNow, (_, _) => DateTime.UtcNow);
+        try
+        {
+            _sessionManager.SendMessageToAdminSessions(SessionMessageType.RefreshProgress, dict, CancellationToken.None);
+        }
+        catch
+        {
+        }
 
-            var dict = new Dictionary<string, string>();
-            dict["ItemId"] = item.Id.ToString("N", CultureInfo.InvariantCulture);
-            dict["Progress"] = progress.ToString(CultureInfo.InvariantCulture);
+        var collectionFolders = _libraryManager.GetCollectionFolders(item);
+
+        foreach (var collectionFolder in collectionFolders)
+        {
+            var collectionFolderDict = new Dictionary<string, string>
+            {
+                ["ItemId"] = collectionFolder.Id.ToString("N", CultureInfo.InvariantCulture),
+                ["Progress"] = (collectionFolder.GetRefreshProgress() ?? 0).ToString(CultureInfo.InvariantCulture)
+            };
 
             try
             {
-                _sessionManager.SendMessageToAdminSessions(SessionMessageType.RefreshProgress, dict, CancellationToken.None);
+                _sessionManager.SendMessageToAdminSessions(SessionMessageType.RefreshProgress, collectionFolderDict, CancellationToken.None);
             }
             catch
             {
             }
+        }
+    }
 
-            var collectionFolders = _libraryManager.GetCollectionFolders(item);
+    private void OnProviderRefreshStarted(object? sender, GenericEventArgs<BaseItem> e)
+    {
+        OnProviderRefreshProgress(sender, new GenericEventArgs<Tuple<BaseItem, double>>(new Tuple<BaseItem, double>(e.Argument, 0)));
+    }
 
-            foreach (var collectionFolder in collectionFolders)
-            {
-                var collectionFolderDict = new Dictionary<string, string>
-                {
-                    ["ItemId"] = collectionFolder.Id.ToString("N", CultureInfo.InvariantCulture),
-                    ["Progress"] = (collectionFolder.GetRefreshProgress() ?? 0).ToString(CultureInfo.InvariantCulture)
-                };
-
-                try
-                {
-                    _sessionManager.SendMessageToAdminSessions(SessionMessageType.RefreshProgress, collectionFolderDict, CancellationToken.None);
-                }
-                catch
-                {
-                }
-            }
-        }
+    private void OnProviderRefreshCompleted(object? sender, GenericEventArgs<BaseItem> e)
+    {
+        OnProviderRefreshProgress(sender, new GenericEventArgs<Tuple<BaseItem, double>>(new Tuple<BaseItem, double>(e.Argument, 100)));
 
-        private void OnProviderRefreshStarted(object sender, GenericEventArgs<BaseItem> e)
-        {
-            OnProviderRefreshProgress(sender, new GenericEventArgs<Tuple<BaseItem, double>>(new Tuple<BaseItem, double>(e.Argument, 0)));
-        }
+        _lastProgressMessageTimes.TryRemove(e.Argument.Id, out _);
+    }
 
-        private void OnProviderRefreshCompleted(object sender, GenericEventArgs<BaseItem> e)
-        {
-            OnProviderRefreshProgress(sender, new GenericEventArgs<Tuple<BaseItem, double>>(new Tuple<BaseItem, double>(e.Argument, 100)));
+    private static bool EnableRefreshMessage(BaseItem item)
+        => item is Folder { IsRoot: false, IsTopParent: true }
+            and not (AggregateFolder or UserRootFolder or UserView or Channel);
 
-            _lastProgressMessageTimes.TryRemove(e.Argument.Id, out _);
-        }
+    private void OnLibraryItemAdded(object? sender, ItemChangeEventArgs e)
+        => OnLibraryChange(e.Item, e.Parent, _itemsAdded, _foldersAddedTo);
 
-        private static bool EnableRefreshMessage(BaseItem item)
+    private void OnLibraryItemUpdated(object? sender, ItemChangeEventArgs e)
+        => OnLibraryChange(e.Item, e.Parent, _itemsUpdated, null);
+
+    private void OnLibraryItemRemoved(object? sender, ItemChangeEventArgs e)
+        => OnLibraryChange(e.Item, e.Parent, _itemsRemoved, _foldersRemovedFrom);
+
+    private void OnLibraryChange(BaseItem item, BaseItem parent, List<BaseItem> itemsList, List<Folder>? foldersList)
+    {
+        if (!FilterItem(item))
         {
-            if (item is not Folder folder)
-            {
-                return false;
-            }
+            return;
+        }
 
-            if (folder.IsRoot)
-            {
-                return false;
-            }
+        lock (_libraryChangedSyncLock)
+        {
+            var updateDuration = TimeSpan.FromSeconds(_configurationManager.Configuration.LibraryUpdateDuration);
 
-            if (folder is AggregateFolder || folder is UserRootFolder)
+            if (_libraryUpdateTimer is null)
             {
-                return false;
+                _libraryUpdateTimer = new Timer(LibraryUpdateTimerCallback, null, updateDuration, Timeout.InfiniteTimeSpan);
             }
-
-            if (folder is UserView || folder is Channel)
+            else
             {
-                return false;
+                _libraryUpdateTimer.Change(updateDuration, Timeout.InfiniteTimeSpan);
             }
 
-            if (!folder.IsTopParent)
+            if (foldersList is not null && parent is Folder folder)
             {
-                return false;
+                foldersList.Add(folder);
             }
 
-            return true;
+            itemsList.Add(item);
         }
+    }
 
-        /// <summary>
-        /// Handles the ItemAdded event of the libraryManager control.
-        /// </summary>
-        /// <param name="sender">The source of the event.</param>
-        /// <param name="e">The <see cref="ItemChangeEventArgs"/> instance containing the event data.</param>
-        private void OnLibraryItemAdded(object sender, ItemChangeEventArgs e)
+    private async void LibraryUpdateTimerCallback(object? state)
+    {
+        List<Folder> foldersAddedTo;
+        List<Folder> foldersRemovedFrom;
+        List<BaseItem> itemsUpdated;
+        List<BaseItem> itemsAdded;
+        List<BaseItem> itemsRemoved;
+        lock (_libraryChangedSyncLock)
         {
-            if (!FilterItem(e.Item))
-            {
-                return;
-            }
+            // Remove dupes in case some were saved multiple times
+            foldersAddedTo = _foldersAddedTo
+                .DistinctBy(x => x.Id)
+                .ToList();
 
-            lock (_libraryChangedSyncLock)
+            foldersRemovedFrom = _foldersRemovedFrom
+                .DistinctBy(x => x.Id)
+                .ToList();
+
+            itemsUpdated = _itemsUpdated
+                .Where(i => !_itemsAdded.Contains(i))
+                .DistinctBy(x => x.Id)
+                .ToList();
+
+            itemsAdded = _itemsAdded.ToList();
+            itemsRemoved = _itemsRemoved.ToList();
+
+            if (_libraryUpdateTimer is not null)
             {
-                if (LibraryUpdateTimer is null)
-                {
-                    LibraryUpdateTimer = new Timer(
-                        LibraryUpdateTimerCallback,
-                        null,
-                        TimeSpan.FromSeconds(_configurationManager.Configuration.LibraryUpdateDuration),
-                        Timeout.InfiniteTimeSpan);
-                }
-                else
-                {
-                    LibraryUpdateTimer.Change(TimeSpan.FromSeconds(_configurationManager.Configuration.LibraryUpdateDuration), Timeout.InfiniteTimeSpan);
-                }
-
-                if (e.Item.GetParent() is Folder parent)
-                {
-                    _foldersAddedTo.Add(parent);
-                }
-
-                _itemsAdded.Add(e.Item);
+                _libraryUpdateTimer.Dispose();
+                _libraryUpdateTimer = null;
             }
+
+            _itemsAdded.Clear();
+            _itemsRemoved.Clear();
+            _itemsUpdated.Clear();
+            _foldersAddedTo.Clear();
+            _foldersRemovedFrom.Clear();
         }
 
-        /// <summary>
-        /// Handles the ItemUpdated event of the libraryManager control.
-        /// </summary>
-        /// <param name="sender">The source of the event.</param>
-        /// <param name="e">The <see cref="ItemChangeEventArgs"/> instance containing the event data.</param>
-        private void OnLibraryItemUpdated(object sender, ItemChangeEventArgs e)
+        await SendChangeNotifications(itemsAdded, itemsUpdated, itemsRemoved, foldersAddedTo, foldersRemovedFrom, CancellationToken.None).ConfigureAwait(false);
+    }
+
+    private async Task SendChangeNotifications(
+        List<BaseItem> itemsAdded,
+        List<BaseItem> itemsUpdated,
+        List<BaseItem> itemsRemoved,
+        List<Folder> foldersAddedTo,
+        List<Folder> foldersRemovedFrom,
+        CancellationToken cancellationToken)
+    {
+        var userIds = _sessionManager.Sessions
+            .Select(i => i.UserId)
+            .Where(i => !i.Equals(default))
+            .Distinct()
+            .ToArray();
+
+        foreach (var userId in userIds)
         {
-            if (!FilterItem(e.Item))
-            {
-                return;
-            }
+            LibraryUpdateInfo info;
 
-            lock (_libraryChangedSyncLock)
+            try
             {
-                if (LibraryUpdateTimer is null)
-                {
-                    LibraryUpdateTimer = new Timer(LibraryUpdateTimerCallback, null, TimeSpan.FromSeconds(_configurationManager.Configuration.LibraryUpdateDuration), Timeout.InfiniteTimeSpan);
-                }
-                else
-                {
-                    LibraryUpdateTimer.Change(TimeSpan.FromSeconds(_configurationManager.Configuration.LibraryUpdateDuration), Timeout.InfiniteTimeSpan);
-                }
-
-                _itemsUpdated.Add(e.Item);
+                info = GetLibraryUpdateInfo(itemsAdded, itemsUpdated, itemsRemoved, foldersAddedTo, foldersRemovedFrom, userId);
             }
-        }
-
-        /// <summary>
-        /// Handles the ItemRemoved event of the libraryManager control.
-        /// </summary>
-        /// <param name="sender">The source of the event.</param>
-        /// <param name="e">The <see cref="ItemChangeEventArgs"/> instance containing the event data.</param>
-        private void OnLibraryItemRemoved(object sender, ItemChangeEventArgs e)
-        {
-            if (!FilterItem(e.Item))
+            catch (Exception ex)
             {
+                _logger.LogError(ex, "Error in GetLibraryUpdateInfo");
                 return;
             }
 
-            lock (_libraryChangedSyncLock)
+            if (info.IsEmpty)
             {
-                if (LibraryUpdateTimer is null)
-                {
-                    LibraryUpdateTimer = new Timer(LibraryUpdateTimerCallback, null, TimeSpan.FromSeconds(_configurationManager.Configuration.LibraryUpdateDuration), Timeout.InfiniteTimeSpan);
-                }
-                else
-                {
-                    LibraryUpdateTimer.Change(TimeSpan.FromSeconds(_configurationManager.Configuration.LibraryUpdateDuration), Timeout.InfiniteTimeSpan);
-                }
-
-                if (e.Parent is Folder parent)
-                {
-                    _foldersRemovedFrom.Add(parent);
-                }
-
-                _itemsRemoved.Add(e.Item);
+                continue;
             }
-        }
 
-        /// <summary>
-        /// Libraries the update timer callback.
-        /// </summary>
-        /// <param name="state">The state.</param>
-        private async void LibraryUpdateTimerCallback(object state)
-        {
-            List<Folder> foldersAddedTo;
-            List<Folder> foldersRemovedFrom;
-            List<BaseItem> itemsUpdated;
-            List<BaseItem> itemsAdded;
-            List<BaseItem> itemsRemoved;
-            lock (_libraryChangedSyncLock)
+            try
             {
-                // Remove dupes in case some were saved multiple times
-                foldersAddedTo = _foldersAddedTo
-                                        .DistinctBy(x => x.Id)
-                                        .ToList();
-
-                foldersRemovedFrom = _foldersRemovedFrom
-                                            .DistinctBy(x => x.Id)
-                                            .ToList();
-
-                itemsUpdated = _itemsUpdated
-                                    .Where(i => !_itemsAdded.Contains(i))
-                                    .DistinctBy(x => x.Id)
-                                    .ToList();
-
-                itemsAdded = _itemsAdded.ToList();
-                itemsRemoved = _itemsRemoved.ToList();
-
-                if (LibraryUpdateTimer is not null)
-                {
-                    LibraryUpdateTimer.Dispose();
-                    LibraryUpdateTimer = null;
-                }
-
-                _itemsAdded.Clear();
-                _itemsRemoved.Clear();
-                _itemsUpdated.Clear();
-                _foldersAddedTo.Clear();
-                _foldersRemovedFrom.Clear();
+                await _sessionManager.SendMessageToUserSessions(
+                        new List<Guid> { userId },
+                        SessionMessageType.LibraryChanged,
+                        info,
+                        cancellationToken)
+                    .ConfigureAwait(false);
             }
-
-            await SendChangeNotifications(itemsAdded, itemsUpdated, itemsRemoved, foldersAddedTo, foldersRemovedFrom, CancellationToken.None).ConfigureAwait(false);
-        }
-
-        /// <summary>
-        /// Sends the change notifications.
-        /// </summary>
-        /// <param name="itemsAdded">The items added.</param>
-        /// <param name="itemsUpdated">The items updated.</param>
-        /// <param name="itemsRemoved">The items removed.</param>
-        /// <param name="foldersAddedTo">The folders added to.</param>
-        /// <param name="foldersRemovedFrom">The folders removed from.</param>
-        /// <param name="cancellationToken">The cancellation token.</param>
-        private async Task SendChangeNotifications(List<BaseItem> itemsAdded, List<BaseItem> itemsUpdated, List<BaseItem> itemsRemoved, List<Folder> foldersAddedTo, List<Folder> foldersRemovedFrom, CancellationToken cancellationToken)
-        {
-            var userIds = _sessionManager.Sessions
-                .Select(i => i.UserId)
-                .Where(i => !i.Equals(default))
-                .Distinct()
-                .ToArray();
-
-            foreach (var userId in userIds)
+            catch (Exception ex)
             {
-                LibraryUpdateInfo info;
-
-                try
-                {
-                    info = GetLibraryUpdateInfo(itemsAdded, itemsUpdated, itemsRemoved, foldersAddedTo, foldersRemovedFrom, userId);
-                }
-                catch (Exception ex)
-                {
-                    _logger.LogError(ex, "Error in GetLibraryUpdateInfo");
-                    return;
-                }
-
-                if (info.IsEmpty)
-                {
-                    continue;
-                }
-
-                try
-                {
-                    await _sessionManager.SendMessageToUserSessions(new List<Guid> { userId }, SessionMessageType.LibraryChanged, info, cancellationToken).ConfigureAwait(false);
-                }
-                catch (Exception ex)
-                {
-                    _logger.LogError(ex, "Error sending LibraryChanged message");
-                }
+                _logger.LogError(ex, "Error sending LibraryChanged message");
             }
         }
+    }
 
-        /// <summary>
-        /// Gets the library update info.
-        /// </summary>
-        /// <param name="itemsAdded">The items added.</param>
-        /// <param name="itemsUpdated">The items updated.</param>
-        /// <param name="itemsRemoved">The items removed.</param>
-        /// <param name="foldersAddedTo">The folders added to.</param>
-        /// <param name="foldersRemovedFrom">The folders removed from.</param>
-        /// <param name="userId">The user id.</param>
-        /// <returns>LibraryUpdateInfo.</returns>
-        private LibraryUpdateInfo GetLibraryUpdateInfo(List<BaseItem> itemsAdded, List<BaseItem> itemsUpdated, List<BaseItem> itemsRemoved, List<Folder> foldersAddedTo, List<Folder> foldersRemovedFrom, Guid userId)
-        {
-            var user = _userManager.GetUserById(userId);
-
-            var newAndRemoved = new List<BaseItem>();
-            newAndRemoved.AddRange(foldersAddedTo);
-            newAndRemoved.AddRange(foldersRemovedFrom);
-
-            var allUserRootChildren = _libraryManager.GetUserRootFolder().GetChildren(user, true).OfType<Folder>().ToList();
-
-            return new LibraryUpdateInfo
-            {
-                ItemsAdded = itemsAdded.SelectMany(i => TranslatePhysicalItemToUserLibrary(i, user)).Select(i => i.Id.ToString("N", CultureInfo.InvariantCulture)).Distinct().ToArray(),
-
-                ItemsUpdated = itemsUpdated.SelectMany(i => TranslatePhysicalItemToUserLibrary(i, user)).Select(i => i.Id.ToString("N", CultureInfo.InvariantCulture)).Distinct().ToArray(),
-
-                ItemsRemoved = itemsRemoved.SelectMany(i => TranslatePhysicalItemToUserLibrary(i, user, true)).Select(i => i.Id.ToString("N", CultureInfo.InvariantCulture)).Distinct().ToArray(),
+    private LibraryUpdateInfo GetLibraryUpdateInfo(
+        List<BaseItem> itemsAdded,
+        List<BaseItem> itemsUpdated,
+        List<BaseItem> itemsRemoved,
+        List<Folder> foldersAddedTo,
+        List<Folder> foldersRemovedFrom,
+        Guid userId)
+    {
+        var user = _userManager.GetUserById(userId);
+        ArgumentNullException.ThrowIfNull(user);
 
-                FoldersAddedTo = foldersAddedTo.SelectMany(i => TranslatePhysicalItemToUserLibrary(i, user)).Select(i => i.Id.ToString("N", CultureInfo.InvariantCulture)).Distinct().ToArray(),
+        var newAndRemoved = new List<BaseItem>();
+        newAndRemoved.AddRange(foldersAddedTo);
+        newAndRemoved.AddRange(foldersRemovedFrom);
 
-                FoldersRemovedFrom = foldersRemovedFrom.SelectMany(i => TranslatePhysicalItemToUserLibrary(i, user)).Select(i => i.Id.ToString("N", CultureInfo.InvariantCulture)).Distinct().ToArray(),
+        var allUserRootChildren = _libraryManager.GetUserRootFolder()
+            .GetChildren(user, true)
+            .OfType<Folder>()
+            .ToList();
 
-                CollectionFolders = GetTopParentIds(newAndRemoved, allUserRootChildren).ToArray()
-            };
-        }
-
-        private static bool FilterItem(BaseItem item)
+        return new LibraryUpdateInfo
         {
-            if (!item.IsFolder && !item.HasPathProtocol)
-            {
-                return false;
-            }
-
-            if (item is IItemByName && item is not MusicArtist)
-            {
-                return false;
-            }
+            ItemsAdded = itemsAdded.SelectMany(i => TranslatePhysicalItemToUserLibrary(i, user))
+                .Select(i => i.Id.ToString("N", CultureInfo.InvariantCulture))
+                .Distinct()
+                .ToArray(),
+            ItemsUpdated = itemsUpdated.SelectMany(i => TranslatePhysicalItemToUserLibrary(i, user))
+                .Select(i => i.Id.ToString("N", CultureInfo.InvariantCulture))
+                .Distinct()
+                .ToArray(),
+            ItemsRemoved = itemsRemoved.SelectMany(i => TranslatePhysicalItemToUserLibrary(i, user, true))
+                .Select(i => i.Id.ToString("N", CultureInfo.InvariantCulture))
+                .Distinct()
+                .ToArray(),
+            FoldersAddedTo = foldersAddedTo.SelectMany(i => TranslatePhysicalItemToUserLibrary(i, user))
+                .Select(i => i.Id.ToString("N", CultureInfo.InvariantCulture))
+                .Distinct()
+                .ToArray(),
+            FoldersRemovedFrom = foldersRemovedFrom.SelectMany(i => TranslatePhysicalItemToUserLibrary(i, user))
+                .Select(i => i.Id.ToString("N", CultureInfo.InvariantCulture))
+                .Distinct()
+                .ToArray(),
+            CollectionFolders = GetTopParentIds(newAndRemoved, allUserRootChildren).ToArray()
+        };
+    }
 
-            return item.SourceType == SourceType.Library;
+    private static bool FilterItem(BaseItem item)
+    {
+        if (!item.IsFolder && !item.HasPathProtocol)
+        {
+            return false;
         }
 
-        private IEnumerable<string> GetTopParentIds(List<BaseItem> items, List<Folder> allUserRootChildren)
+        if (item is IItemByName && item is not MusicArtist)
         {
-            var list = new List<string>();
+            return false;
+        }
 
-            foreach (var item in items)
-            {
-                // If the physical root changed, return the user root
-                if (item is AggregateFolder)
-                {
-                    continue;
-                }
-
-                foreach (var folder in allUserRootChildren)
-                {
-                    list.Add(folder.Id.ToString("N", CultureInfo.InvariantCulture));
-                }
-            }
+        return item.SourceType == SourceType.Library;
+    }
 
-            return list.Distinct(StringComparer.Ordinal);
-        }
+    private IEnumerable<string> GetTopParentIds(List<BaseItem> items, List<Folder> allUserRootChildren)
+    {
+        var list = new List<string>();
 
-        /// <summary>
-        /// Translates the physical item to user library.
-        /// </summary>
-        /// <typeparam name="T">The type of item.</typeparam>
-        /// <param name="item">The item.</param>
-        /// <param name="user">The user.</param>
-        /// <param name="includeIfNotFound">if set to <c>true</c> [include if not found].</param>
-        /// <returns>IEnumerable{``0}.</returns>
-        private IEnumerable<T> TranslatePhysicalItemToUserLibrary<T>(T item, User user, bool includeIfNotFound = false)
-            where T : BaseItem
+        foreach (var item in items)
         {
             // If the physical root changed, return the user root
             if (item is AggregateFolder)
             {
-                return new[] { _libraryManager.GetUserRootFolder() as T };
+                continue;
             }
 
-            // Return it only if it's in the user's library
-            if (includeIfNotFound || item.IsVisibleStandalone(user))
+            foreach (var folder in allUserRootChildren)
             {
-                return new[] { item };
+                list.Add(folder.Id.ToString("N", CultureInfo.InvariantCulture));
             }
+        }
 
-            return Array.Empty<T>();
+        return list.Distinct(StringComparer.Ordinal);
+    }
+
+    private IEnumerable<T> TranslatePhysicalItemToUserLibrary<T>(T item, User user, bool includeIfNotFound = false)
+        where T : BaseItem
+    {
+        // If the physical root changed, return the user root
+        if (item is AggregateFolder)
+        {
+            return _libraryManager.GetUserRootFolder() is T t ? new[] { t } : Array.Empty<T>();
         }
 
-        /// <summary>
-        /// Performs application-defined tasks associated with freeing, releasing, or resetting unmanaged resources.
-        /// </summary>
-        public void Dispose()
+        // Return it only if it's in the user's library
+        if (includeIfNotFound || item.IsVisibleStandalone(user))
         {
-            Dispose(true);
-            GC.SuppressFinalize(this);
+            return new[] { item };
         }
 
-        /// <summary>
-        /// Releases unmanaged and - optionally - managed resources.
-        /// </summary>
-        /// <param name="dispose"><c>true</c> to release both managed and unmanaged resources; <c>false</c> to release only unmanaged resources.</param>
-        protected virtual void Dispose(bool dispose)
+        return Array.Empty<T>();
+    }
+
+    /// <inheritdoc />
+    public void Dispose()
+    {
+        _libraryManager.ItemAdded -= OnLibraryItemAdded;
+        _libraryManager.ItemUpdated -= OnLibraryItemUpdated;
+        _libraryManager.ItemRemoved -= OnLibraryItemRemoved;
+
+        _providerManager.RefreshCompleted -= OnProviderRefreshCompleted;
+        _providerManager.RefreshStarted -= OnProviderRefreshStarted;
+        _providerManager.RefreshProgress -= OnProviderRefreshProgress;
+
+        if (_libraryUpdateTimer is not null)
         {
-            if (dispose)
-            {
-                if (LibraryUpdateTimer is not null)
-                {
-                    LibraryUpdateTimer.Dispose();
-                    LibraryUpdateTimer = null;
-                }
-
-                _libraryManager.ItemAdded -= OnLibraryItemAdded;
-                _libraryManager.ItemUpdated -= OnLibraryItemUpdated;
-                _libraryManager.ItemRemoved -= OnLibraryItemRemoved;
-
-                _providerManager.RefreshCompleted -= OnProviderRefreshCompleted;
-                _providerManager.RefreshStarted -= OnProviderRefreshStarted;
-                _providerManager.RefreshProgress -= OnProviderRefreshProgress;
-            }
+            _libraryUpdateTimer.Dispose();
+            _libraryUpdateTimer = null;
         }
     }
 }