From 5a5e4cae70ec5e71d6d08f0974088183a3dff5e8 Mon Sep 17 00:00:00 2001
From: Steven Hildreth <sphildreth@gmail.com>
Date: Wed, 19 Jan 2022 10:11:09 -0600
Subject: [PATCH] Fix for LastFM returning string empty objects.

---
 .../MetaData/LastFm/JsonEntities.cs           | 28 +++++++++++++++----
 .../MetaData/LastFm/LastFmHelper.cs           |  5 +++-
 2 files changed, 27 insertions(+), 6 deletions(-)

diff --git a/Roadie.Api.Library/SearchEngines/MetaData/LastFm/JsonEntities.cs b/Roadie.Api.Library/SearchEngines/MetaData/LastFm/JsonEntities.cs
index da6377e..521d9ee 100644
--- a/Roadie.Api.Library/SearchEngines/MetaData/LastFm/JsonEntities.cs
+++ b/Roadie.Api.Library/SearchEngines/MetaData/LastFm/JsonEntities.cs
@@ -1,4 +1,7 @@
-using System.Text.Json.Serialization;
+using Roadie.Library.Caching;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text.Json.Serialization;
 
 namespace Roadie.Library.SearchEngines.MetaData.LastFm
 {
@@ -12,8 +15,8 @@ namespace Roadie.Library.SearchEngines.MetaData.LastFm
         public string artist { get; set; }
 
         public string mbid { get; set; }
-
-        public Tags tags { get; set; }
+       
+        public string tags { get; set; }
 
         public string name { get; set; }
 
@@ -26,6 +29,23 @@ namespace Roadie.Library.SearchEngines.MetaData.LastFm
         public string playcount { get; set; }
 
         public string url { get; set; }
+
+        /// <summary>
+        /// Sometimes LastFM returns string empty for an object (?!) and that blows up the serializer. This returns tags if the object value isn't an empty string.
+        /// </summary>
+        public IEnumerable<Tag> GetTags(ICacheSerializer serializer)
+        {
+            if(string.IsNullOrWhiteSpace(tags))
+            {
+                return Enumerable.Empty<Tag>();
+            }
+            var t = serializer.Deserialize<Tags>(tags);
+            if(t != null)
+            {
+                return t.tag;
+            }
+            return Enumerable.Empty<Tag>();
+        }
     }
 
     public class Tags
@@ -58,8 +78,6 @@ namespace Roadie.Library.SearchEngines.MetaData.LastFm
         [JsonPropertyName("@attr")]
         public Attr attr { get; set; }
 
-        //public int? TrackNumber => string.IsNullOrWhiteSpace(attr) ? null : int.Parse(attr.Replace("\"@attr\":{\"rank\":", "").Replace("}", ""));
-
         public int? TrackNumber => attr?.rank;
 
         public Artist artist { get; set; }
diff --git a/Roadie.Api.Library/SearchEngines/MetaData/LastFm/LastFmHelper.cs b/Roadie.Api.Library/SearchEngines/MetaData/LastFm/LastFmHelper.cs
index dca93b5..d47fe5e 100644
--- a/Roadie.Api.Library/SearchEngines/MetaData/LastFm/LastFmHelper.cs
+++ b/Roadie.Api.Library/SearchEngines/MetaData/LastFm/LastFmHelper.cs
@@ -240,7 +240,10 @@ namespace Roadie.Library.MetaData.LastFm
 
                     // No longer fetching/consuming images LastFm says is violation of ToS ; https://getsatisfaction.com/lastfm/topics/api-announcement-dac8oefw5vrxq
 
-                    if (lastFmAlbum.tags != null) result.Tags = lastFmAlbum.tags.tag.Select(x => x.name).ToList();
+                    if (!string.IsNullOrWhiteSpace(lastFmAlbum.tags))
+                    {
+                        result.Tags = lastFmAlbum.GetTags(CacheManager.CacheSerializer)?.Select(x => x.name).ToList();
+                    }
                     if (lastFmAlbum.tracks != null)
                     {
                         var tracks = new List<TrackSearchResult>();