Fix InvalidOperationException in TvdbSeriesProvider

MediaBrowser.Providers/Plugins/TheTvdb/TvdbSeriesProvider.cs

@@ -123,7 +123,7 @@ namespace MediaBrowser.Providers.Plugins.TheTvdb
                     await _tvdbClientManager
                         .GetSeriesByIdAsync(Convert.ToInt32(tvdbId), metadataLanguage, cancellationToken)
                         .ConfigureAwait(false);
-                MapSeriesToResult(result, seriesResult.Data, metadataLanguage);
+                await MapSeriesToResult(result, seriesResult.Data, metadataLanguage).ConfigureAwait(false);
             }
             catch (TvDbServerException e)
             {
@@ -297,7 +297,7 @@ namespace MediaBrowser.Providers.Plugins.TheTvdb
             return name.Trim();
         }
 
-        private void MapSeriesToResult(MetadataResult<Series> result, TvDbSharper.Dto.Series tvdbSeries, string metadataLanguage)
+        private async Task MapSeriesToResult(MetadataResult<Series> result, TvDbSharper.Dto.Series tvdbSeries, string metadataLanguage)
         {
             Series series = result.Item;
             series.SetProviderId(MetadataProvider.Tvdb, tvdbSeries.Id.ToString());
@@ -340,20 +340,25 @@ namespace MediaBrowser.Providers.Plugins.TheTvdb
             {
                 try
                 {
-                    var episodeSummary = _tvdbClientManager
-                        .GetSeriesEpisodeSummaryAsync(tvdbSeries.Id, metadataLanguage, CancellationToken.None).Result.Data;
-                    var maxSeasonNumber = episodeSummary.AiredSeasons.Select(s => Convert.ToInt32(s)).Max();
+                    var episodeSummary = await _tvdbClientManager.GetSeriesEpisodeSummaryAsync(tvdbSeries.Id, metadataLanguage, CancellationToken.None).ConfigureAwait(false);
+
+                    if (episodeSummary.Data.AiredSeasons.Length > 0)
+                    {
+                        var maxSeasonNumber = episodeSummary.Data.AiredSeasons.Select(s => Convert.ToInt32(s)).Max();
                         var episodeQuery = new EpisodeQuery
                         {
                             AiredSeason = maxSeasonNumber
                         };
-                    var episodesPage =
-                        _tvdbClientManager.GetEpisodesPageAsync(tvdbSeries.Id, episodeQuery, metadataLanguage, CancellationToken.None).Result.Data;
-                    result.Item.EndDate = episodesPage.Select(e =>
+                        var episodesPage = await _tvdbClientManager.GetEpisodesPageAsync(tvdbSeries.Id, episodeQuery, metadataLanguage, CancellationToken.None).ConfigureAwait(false);
+
+                        var episodeDates = episodesPage.Data
+                            .Select(e => DateTime.TryParse(e.FirstAired, out var firstAired) ? firstAired : (DateTime?)null)
+                            .Where(dt => dt.HasValue);
+                        if (episodeDates.Any())
                         {
-                            DateTime.TryParse(e.FirstAired, out var firstAired);
-                            return firstAired;
-                        }).Max();
+                            result.Item.EndDate = episodeDates.Max().Value;
+                        }
+                    }
                 }
                 catch (TvDbServerException e)
                 {