Expose optimized ItemCounts for byName items

MediaBrowser.Controller/Library/ILibraryManager.cs

@@ -759,6 +759,17 @@ namespace MediaBrowser.Controller.Library
         /// <returns>The item counts grouped by type.</returns>
         ItemCounts GetItemCountsForNameItem(BaseItemKind kind, Guid id, BaseItemKind[] relatedItemKinds, User? user);
 
+        /// <summary>
+        /// Gets item counts for several "by-name" items of the same kind in one query, instead of
+        /// one query per item.
+        /// </summary>
+        /// <param name="kind">The kind of the name items.</param>
+        /// <param name="ids">The IDs of the name items.</param>
+        /// <param name="relatedItemKinds">The item kinds to count.</param>
+        /// <param name="user">The user for access filtering.</param>
+        /// <returns>The item counts of each requested id.</returns>
+        Dictionary<Guid, ItemCounts> GetItemCountsForNameItems(BaseItemKind kind, IReadOnlyList<Guid> ids, BaseItemKind[] relatedItemKinds, User? user);
+
         /// <summary>
         /// Batch-fetches child counts for multiple parent folders.
         /// Returns the count of immediate children (non-recursive) for each parent.

MediaBrowser.Controller/Persistence/IItemCountService.cs

@@ -36,6 +36,16 @@ public interface IItemCountService
     /// <returns>The item counts grouped by type.</returns>
     ItemCounts GetItemCountsForNameItem(BaseItemKind kind, Guid id, BaseItemKind[] relatedItemKinds, InternalItemsQuery accessFilter);
 
+    /// <summary>
+    /// Gets item counts for several "by-name" items of the same kind in one query.
+    /// </summary>
+    /// <param name="kind">The kind of the name items.</param>
+    /// <param name="ids">The IDs of the name items.</param>
+    /// <param name="relatedItemKinds">The item kinds to count.</param>
+    /// <param name="accessFilter">A pre-configured query with user access filtering settings.</param>
+    /// <returns>The item counts of each requested id.</returns>
+    Dictionary<Guid, ItemCounts> GetItemCountsForNameItems(BaseItemKind kind, IReadOnlyList<Guid> ids, BaseItemKind[] relatedItemKinds, InternalItemsQuery accessFilter);
+
     /// <summary>
     /// Gets the count of played items that are descendants of the specified ancestor.
     /// </summary>