2 files changed, 72 insertions, 1 deletions
diff --git a/MediaBrowser.Providers/Manager/MetadataLanguageUtils.cs b/MediaBrowser.Providers/Manager/MetadataLanguageUtils.cs
new file mode 100644
index 0000000000..92a16feaee
--- /dev/null
+++ b/MediaBrowser.Providers/Manager/MetadataLanguageUtils.cs
@@ -0,0 +1,44 @@
+using System;
+
+namespace MediaBrowser.Providers.Manager;
+
+/// <summary>
+/// Helpers for comparing the language of fetched metadata with the language that was requested.
+/// </summary>
+internal static class MetadataLanguageUtils
+{
+    /// <summary>
+    /// Gets the language subtag of a language tag, e.g. "es" for "es-ES".
+    /// </summary>
+    /// <param name="language">The language tag.</param>
+    /// <returns>The language subtag, lowercased, or <c>null</c> if none was given.</returns>
+    public static string? GetLanguageSubtag(string? language)
+    {
+        if (string.IsNullOrEmpty(language))
+        {
+            return null;
+        }
+
+        var separator = language.IndexOf('-', StringComparison.Ordinal);
+
+        return (separator == -1 ? language : language[..separator]).ToLowerInvariant();
+    }
+
+    /// <summary>
+    /// Determines whether a provider result can be considered to be in the requested language.
+    /// </summary>
+    /// <param name="resultLanguage">The language the provider reported for its result, if any.</param>
+    /// <param name="preferredLanguage">The language that was requested, if any.</param>
+    /// <returns><c>true</c> if the result is in the requested language or either language is unknown.</returns>
+    public static bool MatchesPreferredLanguage(string? resultLanguage, string? preferredLanguage)
+    {
+        // A provider that doesn't report a language cannot be judged, assume it honored the request
+        if (string.IsNullOrEmpty(resultLanguage) || string.IsNullOrEmpty(preferredLanguage))
+        {
+            return true;
+        }
+
+        // Compare on the language subtag only so that e.g. "es" matches "es-ES"
+        return string.Equals(GetLanguageSubtag(resultLanguage), GetLanguageSubtag(preferredLanguage), StringComparison.Ordinal);
+    }
+}
diff --git a/MediaBrowser.Providers/Manager/MetadataService.cs b/MediaBrowser.Providers/Manager/MetadataService.cs
index d11db8f531..26dc8f9930 100644
--- a/MediaBrowser.Providers/Manager/MetadataService.cs
+++ b/MediaBrowser.Providers/Manager/MetadataService.cs
@@ -209,7 +209,10 @@ namespace MediaBrowser.Providers.Manager
                 }
             }
 
-            if (hasRefreshedMetadata && hasRefreshedImages)
+            var attemptedFetch = refreshOptions.MetadataRefreshMode > MetadataRefreshMode.ValidationOnly
+                || refreshOptions.ImageRefreshMode > MetadataRefreshMode.ValidationOnly;
+
+            if (hasRefreshedMetadata && hasRefreshedImages && attemptedFetch)
             {
                 item.DateLastRefreshed = DateTime.UtcNow;
                 updateType |= item.OnMetadataChanged();
@@ -939,6 +942,10 @@ namespace MediaBrowser.Providers.Manager
         private async Task<RefreshResult> ExecuteRemoteProviders(MetadataResult<TItemType> temp, string logName, bool replaceData, TIdType id, IEnumerable<IRemoteMetadataProvider<TItemType, TIdType>> providers, CancellationToken cancellationToken)
         {
             var refreshResult = new RefreshResult();
+            var preferredLanguage = id?.MetadataLanguage;
+
+            var overviewIsFallback = false;
+            var taglineIsFallback = false;
 
             if (id is not null)
             {
@@ -958,6 +965,26 @@ namespace MediaBrowser.Providers.Manager
                     {
                         result.Provider = provider.Name;
 
+                        if (MetadataLanguageUtils.MatchesPreferredLanguage(result.ResultLanguage, preferredLanguage))
+                        {
+                            if (overviewIsFallback && !string.IsNullOrEmpty(result.Item.Overview))
+                            {
+                                temp.Item.Overview = null;
+                                overviewIsFallback = false;
+                            }
+
+                            if (taglineIsFallback && !string.IsNullOrEmpty(result.Item.Tagline))
+                            {
+                                temp.Item.Tagline = null;
+                                taglineIsFallback = false;
+                            }
+                        }
+                        else
+                        {
+                            overviewIsFallback |= string.IsNullOrEmpty(temp.Item.Overview) && !string.IsNullOrEmpty(result.Item.Overview);
+                            taglineIsFallback |= string.IsNullOrEmpty(temp.Item.Tagline) && !string.IsNullOrEmpty(result.Item.Tagline);
+                        }
+
                         LogInvalidProviderIds(result, providerName, logName);
 
                         MergeData(result, temp, [], replaceData, false);