Add language-aware article sorting

tests/Jellyfin.Plugin.Multilang.Tests/ItemsProxySortingTests.cs

@@ -8,7 +8,7 @@ namespace Jellyfin.Plugin.Multilang.Tests;
 public sealed class ItemsProxySortingTests
 {
     [Fact]
-    public void GetSortArticlesUsesBuiltInLocaleFallback()
+    public void GetSortArticlesUsesBuiltInLanguageFallback()
     {
         var articles = ItemsProxySorting.GetSortArticles(new SortArticleCatalog(), [], "sv-FI");
 
@@ -27,7 +27,7 @@ public sealed class ItemsProxySortingTests
     }
 
     [Fact]
-    public void GetSortArticlesPrefersConfiguredExactLocale()
+    public void GetSortArticlesPrefersConfiguredExactLanguage()
     {
         var articles = ItemsProxySorting.GetSortArticles(
             new SortArticleCatalog(),
@@ -40,6 +40,32 @@ public sealed class ItemsProxySortingTests
         Assert.Equal(["exact"], articles);
     }
 
+    [Fact]
+    public void GetSortArticlesIncludesAlwaysIgnoredArticlesFromOtherLanguages()
+    {
+        var articles = ItemsProxySorting.GetSortArticles(
+            new SortArticleCatalog(),
+            [
+                new SortArticleEntry { Language = "en", Articles = "a, an, the", AlwaysApply = true },
+                new SortArticleEntry { Language = "it", Articles = "il, lo, la" }
+            ],
+            "it");
+
+        Assert.Equal(["a", "an", "the", "il", "lo", "la"], articles);
+    }
+
+    [Fact]
+    public void GetSortArticlesReturnsNoneWhenArticleIgnoringIsDisabled()
+    {
+        var articles = ItemsProxySorting.GetSortArticles(
+            new SortArticleCatalog(),
+            [new SortArticleEntry { Language = "en", Articles = "a, an, the", AlwaysApply = true }],
+            "en",
+            ignoreArticles: false);
+
+        Assert.Empty(articles);
+    }
+
     [Fact]
     public void ApplySortsByTitleAfterLeadingArticles()
     {
@@ -54,6 +80,41 @@ public sealed class ItemsProxySortingTests
         Assert.Equal(["Avatar", "A Beautiful Mind", "The Matrix"], ItemNames(root));
     }
 
+    [Fact]
+    public void ApplyUsesEachTitlesLanguageForArticleRemoval()
+    {
+        var root = ItemsRoot("La La Land", "La vita e bella", "Terminator", "The Matrix");
+        var articles = new Dictionary<string, string[]>(StringComparer.Ordinal)
+        {
+            ["La La Land"] = [],
+            ["La vita e bella"] = ["il", "lo", "la"],
+            ["Terminator"] = [],
+            ["The Matrix"] = ["a", "an", "the"]
+        };
+
+        ItemsProxySorting.Apply(
+            root,
+            new ItemsProxyControls("SortName", "Ascending", "", 0, 0, "en-US", ""),
+            CultureInfo.GetCultureInfo("en-US"),
+            item => articles[item["Name"]!.GetValue<string>()]);
+
+        Assert.Equal(["La La Land", "The Matrix", "Terminator", "La vita e bella"], ItemNames(root));
+    }
+
+    [Fact]
+    public void ApplyStripsApostropheArticles()
+    {
+        var root = ItemsRoot("L'avventura", "The Matrix");
+
+        ItemsProxySorting.Apply(
+            root,
+            new ItemsProxyControls("SortName", "Ascending", "", 0, 0, "en-US", ""),
+            CultureInfo.GetCultureInfo("en-US"),
+            item => item["Name"]!.GetValue<string>() == "L'avventura" ? ["l'"] : ["the"]);
+
+        Assert.Equal(["L'avventura", "The Matrix"], ItemNames(root));
+    }
+
     [Fact]
     public void ApplyPadsNumbersDuringTitleSort()
     {

tests/Jellyfin.Plugin.Multilang.Tests/ItemsProxyTransformerResolutionTests.cs

@@ -29,6 +29,7 @@ public sealed class ItemsProxyTransformerResolutionTests
 
         Assert.True(result.Change);
         Assert.Equal("Finnish overview", result.Value);
+        Assert.Equal("fi", result.Language);
     }
 
     [Fact]
@@ -37,11 +38,12 @@ public sealed class ItemsProxyTransformerResolutionTests
         var result = ItemsProxyTransformer.ResolveField(
             TitleField,
             [OriginalAction, LanguagePrefix + "en"],
-            Facts(originalTitle: "Original title"),
+            Facts(originalTitle: "Original title", originalLanguage: "en"),
             TextTranslations(("en", TitleField, "English title")));
 
         Assert.True(result.Change);
         Assert.Equal("Original title", result.Value);
+        Assert.Equal("en", result.Language);
     }
 
     [Fact]
@@ -55,6 +57,7 @@ public sealed class ItemsProxyTransformerResolutionTests
 
         Assert.False(result.Change);
         Assert.Null(result.Value);
+        Assert.Null(result.Language);
     }
 
     [Fact]
@@ -145,13 +148,13 @@ public sealed class ItemsProxyTransformerResolutionTests
         return result;
     }
 
-    private static FactsData Facts(string originalTitle = "")
+    private static FactsData Facts(string originalTitle = "", string originalLanguage = "")
         => new(
             "item",
             "tmdb",
             "movie",
             originalTitle,
-            "",
+            originalLanguage,
             "",
             "[]",
             "[]",