New: Check whether an existing episode file was deleted before grabbing an upgrade, to avoid timing issues in combination with Ignore Deleted Episodes.

src/NzbDrone.Core/DecisionEngine/Specifications/RssSync/DelaySpecification.cs

@@ -26,6 +26,7 @@ namespace NzbDrone.Core.DecisionEngine.Specifications.RssSync
             _logger = logger;
         }
 
+        public SpecificationPriority Priority => SpecificationPriority.Database;
         public RejectionType Type => RejectionType.Temporary;
 
         public virtual Decision IsSatisfiedBy(RemoteEpisode subject, SearchCriteriaBase searchCriteria)

src/NzbDrone.Core/DecisionEngine/Specifications/RssSync/DeletedEpisodeFileSpecification.cs

@@ -0,0 +1,71 @@
+using System.IO;
+using System.Linq;
+using NLog;
+using NzbDrone.Common.Disk;
+using NzbDrone.Common.Extensions;
+using NzbDrone.Core.Configuration;
+using NzbDrone.Core.IndexerSearch.Definitions;
+using NzbDrone.Core.MediaFiles;
+using NzbDrone.Core.Parser.Model;
+using NzbDrone.Core.Tv;
+
+namespace NzbDrone.Core.DecisionEngine.Specifications.RssSync
+{
+    public class DeletedEpisodeFileSpecification : IDecisionEngineSpecification
+    {
+        private readonly IDiskProvider _diskProvider;
+        private readonly IConfigService _configService;
+        private readonly Logger _logger;
+
+        public DeletedEpisodeFileSpecification(IDiskProvider diskProvider, IConfigService configService, Logger logger)
+        {
+            _diskProvider = diskProvider;
+            _configService = configService;
+            _logger = logger;
+        }
+
+        public SpecificationPriority Priority => SpecificationPriority.Disk;
+        public RejectionType Type => RejectionType.Temporary;
+
+        public virtual Decision IsSatisfiedBy(RemoteEpisode subject, SearchCriteriaBase searchCriteria)
+        {
+            if (!_configService.AutoUnmonitorPreviouslyDownloadedEpisodes)
+            {
+                return Decision.Accept();
+            }
+
+            if (searchCriteria != null)
+            {
+                _logger.Debug("Skipping deleted episodefile check during search");
+                return Decision.Accept();
+            }
+
+            var missingEpisodeFiles = subject.Episodes
+                                             .Where(v => v.EpisodeFileId != 0)
+                                             .Select(v => v.EpisodeFile.Value)
+                                             .DistinctBy(v => v.Id)
+                                             .Where(v => IsEpisodeFileMissing(subject.Series, v))
+                                             .ToArray();
+
+            if (missingEpisodeFiles.Any())
+            {
+                foreach (var missingEpisodeFile in missingEpisodeFiles)
+                {
+                    _logger.Trace("Episode file {0} is missing from disk.", missingEpisodeFile.RelativePath);
+                }
+
+                _logger.Debug("Files for this episode exist in the database but not on disk, will be unmonitored on next diskscan. skipping.");
+                return Decision.Reject("Series is not monitored");
+            }
+
+            return Decision.Accept();
+        }
+
+        private bool IsEpisodeFileMissing(Series series, EpisodeFile episodeFile)
+        {
+            var fullPath = Path.Combine(series.Path, episodeFile.RelativePath);
+
+            return !_diskProvider.FileExists(fullPath);
+        }
+    }
+}

src/NzbDrone.Core/DecisionEngine/Specifications/RssSync/HistorySpecification.cs

@@ -26,6 +26,7 @@ namespace NzbDrone.Core.DecisionEngine.Specifications.RssSync
             _logger = logger;
         }
 
+        public SpecificationPriority Priority => SpecificationPriority.Database;
         public RejectionType Type => RejectionType.Permanent;
 
         public virtual Decision IsSatisfiedBy(RemoteEpisode subject, SearchCriteriaBase searchCriteria)
@@ -59,7 +60,7 @@ namespace NzbDrone.Core.DecisionEngine.Specifications.RssSync
                     {
                         if (recent)
                         {
-                            return Decision.Reject("Recent grab event in history already meets cutoff: {0}", mostRecent.Quality);  
+                            return Decision.Reject("Recent grab event in history already meets cutoff: {0}", mostRecent.Quality);
                         }
 
                         return Decision.Reject("CDH is disabled and grab event in history already meets cutoff: {0}", mostRecent.Quality);

src/NzbDrone.Core/DecisionEngine/Specifications/RssSync/MonitoredEpisodeSpecification.cs

@@ -14,6 +14,7 @@ namespace NzbDrone.Core.DecisionEngine.Specifications.RssSync
             _logger = logger;
         }
 
+        public SpecificationPriority Priority => SpecificationPriority.Default;
         public RejectionType Type => RejectionType.Permanent;
 
         public virtual Decision IsSatisfiedBy(RemoteEpisode subject, SearchCriteriaBase searchCriteria)

src/NzbDrone.Core/DecisionEngine/Specifications/RssSync/ProperSpecification.cs

@@ -20,6 +20,7 @@ namespace NzbDrone.Core.DecisionEngine.Specifications.RssSync
             _logger = logger;
         }
 
+        public SpecificationPriority Priority => SpecificationPriority.Default;
         public RejectionType Type => RejectionType.Permanent;
 
         public virtual Decision IsSatisfiedBy(RemoteEpisode subject, SearchCriteriaBase searchCriteria)