1 files changed, 80 insertions, 9 deletions

diff --git a/MediaBrowser.Model/Entities/ProviderIdsExtensions.cs b/MediaBrowser.Model/Entities/ProviderIdsExtensions.cs
index 385a86d31c..09eba92d9e 100644
--- a/MediaBrowser.Model/Entities/ProviderIdsExtensions.cs
+++ b/MediaBrowser.Model/Entities/ProviderIdsExtensions.cs
@@ -1,14 +1,16 @@
 using System;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using System.Globalization;
 using System.Linq;
+using System.Text.RegularExpressions;
 
 namespace MediaBrowser.Model.Entities;
 
 /// <summary>
 /// Class ProviderIdsExtensions.
 /// </summary>
-public static class ProviderIdsExtensions
+public static partial class ProviderIdsExtensions
 {
     /// <summary>
     /// Case-insensitive dictionary of <see cref="MetadataProvider"/> string representation.
@@ -21,6 +23,27 @@ public static class ProviderIdsExtensions
                 StringComparer.OrdinalIgnoreCase);
 
     /// <summary>
+    /// The known id formats, keyed by provider name.
+    /// </summary>
+    private static readonly Dictionary<string, Func<string, bool>> _providerIdValidators =
+        new(StringComparer.OrdinalIgnoreCase)
+        {
+            [MetadataProvider.Imdb.ToString()] = value => ImdbIdRegex().IsMatch(value),
+            [MetadataProvider.Tmdb.ToString()] = IsPositiveNumber,
+            [MetadataProvider.TmdbCollection.ToString()] = IsPositiveNumber,
+            [MetadataProvider.AudioDbArtist.ToString()] = IsPositiveNumber,
+            [MetadataProvider.AudioDbAlbum.ToString()] = IsPositiveNumber,
+
+            // Every MusicBrainz id is an MBID.
+            [MetadataProvider.MusicBrainzAlbum.ToString()] = IsGuid,
+            [MetadataProvider.MusicBrainzAlbumArtist.ToString()] = IsGuid,
+            [MetadataProvider.MusicBrainzArtist.ToString()] = IsGuid,
+            [MetadataProvider.MusicBrainzReleaseGroup.ToString()] = IsGuid,
+            [MetadataProvider.MusicBrainzRecording.ToString()] = IsGuid,
+            [MetadataProvider.MusicBrainzTrack.ToString()] = IsGuid
+        };
+
+    /// <summary>
     /// Checks if this instance has an id for the given provider.
     /// </summary>
     /// <param name="instance">The instance.</param>
@@ -102,6 +125,26 @@ public static class ProviderIdsExtensions
     }
 
     /// <summary>
+    /// Checks whether a value can be an id of the given provider.
+    /// </summary>
+    /// <param name="name">The provider name.</param>
+    /// <param name="value">The provider id.</param>
+    /// <returns><c>true</c> if the value has a plausible format for the provider; otherwise, <c>false</c>.</returns>
+    /// <remarks>
+    /// Providers regularly hand out an id belonging to a different service, e.g. an IMDb person id in the
+    /// TMDb field. Such an id is not just useless, it also makes the owning provider fail for the item.
+    /// </remarks>
+    public static bool IsValidProviderId(string? name, string? value)
+    {
+        if (string.IsNullOrWhiteSpace(name) || string.IsNullOrWhiteSpace(value))
+        {
+            return false;
+        }
+
+        return !_providerIdValidators.TryGetValue(name, out var isValid) || isValid(value);
+    }
+
+    /// <summary>
     /// Sets a provider id.
     /// </summary>
     /// <param name="instance">The instance.</param>
@@ -121,6 +164,14 @@ public static class ProviderIdsExtensions
             return false;
         }
 
+        name = name.Trim();
+        value = value.Trim();
+
+        if (!IsValidProviderId(name, value))
+        {
+            return false;
+        }
+
         // Ensure it exists
         instance.ProviderIds ??= new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
 
@@ -153,7 +204,6 @@ public static class ProviderIdsExtensions
     /// <param name="instance">The instance.</param>
     /// <param name="name">The name, this should not contain a '=' character.</param>
     /// <param name="value">The value.</param>
-    /// <remarks>Due to how deserialization from the database works the name cannot contain '='.</remarks>
     public static void SetProviderId(this IHasProviderIds instance, string name, string value)
     {
         ArgumentNullException.ThrowIfNull(instance);
@@ -166,17 +216,27 @@ public static class ProviderIdsExtensions
             throw new ArgumentException("Provider id name cannot contain '='", nameof(name));
         }
 
-        // Ensure it exists
-        instance.ProviderIds ??= new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
+        instance.TrySetProviderId(name, value);
+    }
 
-        // Match on internal MetadataProvider enum string values before adding arbitrary providers
-        if (_metadataProviderEnumDictionary.TryGetValue(name, out var enumValue))
+    /// <summary>
+    /// Replaces all provider ids, dropping the ones that cannot belong to the provider they are filed under.
+    /// </summary>
+    /// <param name="instance">The instance.</param>
+    /// <param name="providerIds">The provider ids to set.</param>
+    public static void SetProviderIds(this IHasProviderIds instance, IReadOnlyDictionary<string, string>? providerIds)
+    {
+        ArgumentNullException.ThrowIfNull(instance);
+
+        instance.ProviderIds = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase);
+        if (providerIds is null)
         {
-            instance.ProviderIds[enumValue] = value;
+            return;
         }
-        else
+
+        foreach (var (name, value) in providerIds)
         {
-            instance.ProviderIds[name] = value;
+            instance.TrySetProviderId(name, value);
         }
     }
 
@@ -213,4 +273,15 @@ public static class ProviderIdsExtensions
 
         instance.ProviderIds?.Remove(provider.ToString());
     }
+
+    private static bool IsPositiveNumber(string value)
+        => int.TryParse(value, NumberStyles.None, CultureInfo.InvariantCulture, out var id) && id > 0;
+
+    private static bool IsGuid(string value)
+        => Guid.TryParse(value, CultureInfo.InvariantCulture, out _);
+
+    // An IMDb id is a type prefix (tt for titles, nm for people, co for companies, ...) followed by
+    // digits. The prefix is optional because a bare number has always been accepted for a title.
+    [GeneratedRegex(@"^(tt|nm|co|ev|ch|ni)?[0-9]+$", RegexOptions.IgnoreCase)]
+    private static partial Regex ImdbIdRegex();
 }