1 files changed, 70 insertions, 0 deletions
diff --git a/MediaBrowser.Controller/Library/ISimilarItemsManager.cs b/MediaBrowser.Controller/Library/ISimilarItemsManager.cs
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+++ b/MediaBrowser.Controller/Library/ISimilarItemsManager.cs
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+using System;
+using System.Collections.Generic;
+using System.Threading;
+using System.Threading.Tasks;
+using Jellyfin.Database.Implementations.Entities;
+using MediaBrowser.Controller.Dto;
+using MediaBrowser.Controller.Entities;
+using MediaBrowser.Model.Configuration;
+using MediaBrowser.Model.Dto;
+
+namespace MediaBrowser.Controller.Library;
+
+/// <summary>
+/// Interface for managing similar items providers and operations.
+/// </summary>
+public interface ISimilarItemsManager
+{
+    /// <summary>
+    /// Registers similar items providers discovered through dependency injection.
+    /// </summary>
+    /// <param name="providers">The similar items providers to register.</param>
+    void AddParts(IEnumerable<ISimilarItemsProvider> providers);
+
+    /// <summary>
+    /// Gets the similar items providers for a specific item type.
+    /// </summary>
+    /// <typeparam name="T">The item type.</typeparam>
+    /// <returns>The list of similar items providers for that type.</returns>
+    IReadOnlyList<ISimilarItemsProvider> GetSimilarItemsProviders<T>()
+        where T : BaseItem;
+
+    /// <summary>
+    /// Gets similar items for the specified item.
+    /// </summary>
+    /// <param name="item">The source item to find similar items for.</param>
+    /// <param name="excludeArtistIds">Artist IDs to exclude from results.</param>
+    /// <param name="user">The user context.</param>
+    /// <param name="dtoOptions">The DTO options.</param>
+    /// <param name="limit">Maximum number of results.</param>
+    /// <param name="libraryOptions">The library options for provider configuration.</param>
+    /// <param name="cancellationToken">The cancellation token.</param>
+    /// <returns>The list of similar items.</returns>
+    Task<IReadOnlyList<BaseItem>> GetSimilarItemsAsync(
+        BaseItem item,
+        IReadOnlyList<Guid> excludeArtistIds,
+        User? user,
+        DtoOptions dtoOptions,
+        int? limit,
+        LibraryOptions? libraryOptions,
+        CancellationToken cancellationToken);
+
+    /// <summary>
+    /// Builds movie recommendations for a user: a mix of similar-items and person-based categories,
+    /// scheduled round-robin and capped to <paramref name="categoryLimit"/>.
+    /// </summary>
+    /// <param name="user">The user the recommendations are for. May be <see langword="null"/> for anonymous access.</param>
+    /// <param name="parentId">The library/folder to localize the search to. Pass <see cref="Guid.Empty"/> to use the root.</param>
+    /// <param name="categoryLimit">Maximum number of recommendation categories to return.</param>
+    /// <param name="itemLimit">Maximum number of items per category.</param>
+    /// <param name="dtoOptions">DTO options used when querying the library.</param>
+    /// <param name="cancellationToken">The cancellation token.</param>
+    /// <returns>The list of recommendation categories, ordered by <see cref="RecommendationType"/>.</returns>
+    Task<IReadOnlyList<SimilarItemsRecommendation>> GetMovieRecommendationsAsync(
+        User? user,
+        Guid parentId,
+        int categoryLimit,
+        int itemLimit,
+        DtoOptions dtoOptions,
+        CancellationToken cancellationToken);
+}