Folder Watching (#1467)

* Hooked in a server setting to enable/disable folder watching

* Validated the file rename change event

* Validated delete file works

* Tweaked some logic to determine if a change occurs on a folder or a file.

* Added a note for an upcoming branch

* Some minor changes in the loop that just shift where code runs.

* Implemented ScanFolder api

* Ensure we restart watchers when we modify a library folder.

* Fixed a unit test

API/Services/Tasks/ScannerService.cs

@@ -100,8 +100,6 @@ public class ScannerService : IScannerService
     [Queue(TaskScheduler.ScanQueue)]
     public async Task ScanFolder(string folder)
     {
-        // NOTE: I might want to move a lot of this code to the LibraryWatcher or something and just pack libraryId and seriesId
-        // Validate if we are scanning a new series (that belongs to a library) or an existing series
         var seriesId = await _unitOfWork.SeriesRepository.GetSeriesIdByFolder(folder);
         if (seriesId > 0)
         {
@@ -109,6 +107,7 @@ public class ScannerService : IScannerService
             return;
         }
 
+        // This is basically rework of what's already done in Library Watcher but is needed if invoked via API
         var parentDirectory = _directoryService.GetParentDirectoryName(folder);
         if (string.IsNullOrEmpty(parentDirectory)) return; // This should never happen as it's calculated before enqueing
 
@@ -456,6 +455,8 @@ public class ScannerService : IScannerService
                 Format = parsedFiles.First().Format
             };
 
+            // NOTE: Could we check if there are multiple found series (different series) and process each one? 
+
             if (skippedScan)
             {
                 seenSeries.AddRange(parsedFiles.Select(pf => new ParsedSeries()