private IEnumerator <object> ScanReferenceDirectory()
{
m_ScanningDirectory = true;
HashSet <string> changedSet = null;
// We do a switcheroo on the changed list here so that there isn't a conflict with it
// if a filewatch callback happens.
lock (m_ChangedFiles) {
changedSet = m_ChangedFiles;
m_ChangedFiles = new HashSet <string>();
}
var existing = new HashSet <string>(m_Videos.Select(x => x.AbsolutePath));
var detected = new HashSet <string>(
Directory.GetFiles(App.VideoLibraryPath(), "*.*", SearchOption.AllDirectories).
Where(x => m_supportedVideoExtensions.Contains(Path.GetExtension(x))));
var toDelete = existing.Except(detected).Concat(changedSet).ToArray();
var toScan = detected.Except(existing).Concat(changedSet).ToArray();
// Remove deleted videos from the list. Currently playing videos may continue to play, but will
// not appear in the reference panel.
m_Videos.RemoveAll(x => toDelete.Contains(x.AbsolutePath));
var newVideos = new List <ReferenceVideo>();
foreach (var filePath in toScan)
{
ReferenceVideo videoRef = new ReferenceVideo(filePath);
newVideos.Add(videoRef);
m_Videos.Add(videoRef);
}
// If we have a lot of videos, they may take a while to create thumbnails. Make sure we refresh
// every few seconds so the user sees progress if they go straight to the reference panel.
TimeSpan interval = TimeSpan.FromSeconds(4);
DateTime nextRefresh = DateTime.Now + interval;
foreach (var videoRef in newVideos)
{
if (DateTime.Now > nextRefresh)
{
CatalogChanged?.Invoke();
nextRefresh = DateTime.Now + interval;
}
yield return(videoRef.Initialize());
}
m_ScanningDirectory = false;
CatalogChanged?.Invoke();
if (m_DebugOutput)
{
DebugListVideos();
}
}