Added "last" and a reversed ?playlistPosition in playlist URL (#3974)

* Added "last" and a reversed playlistPosition

Implements https://github.com/Chocobozzz/PeerTube/issues/3897

* Fixed lint errors in video-watch component

* Applied requested changes

* Removed debug logs

* Fixed lint

* Playlist position styling

Co-authored-by: Chocobozzz <me@florianbigard.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/client/src/app/+videos/+video-watch/video-watch-playlist.component.ts b/client/src/app/+videos/+video-watch/video-watch-playlist.component.ts
index a70167da5..0a4d6bfd1 100644
--- a/client/src/app/+videos/+video-watch/video-watch-playlist.component.ts
+++ b/client/src/app/+videos/+video-watch/video-watch-playlist.component.ts
@@ -118,6 +118,9 @@ export class VideoWatchPlaylistComponent {
   updatePlaylistIndex (position: number) {
     if (this.playlistElements.length === 0 || !position) return
 
+    // Handle the reverse index
+    if (position < 0) position = this.playlist.videosLength + position + 1
+
     for (const playlistElement of this.playlistElements) {
       // >= if the previous videos were not valid
       if (playlistElement.video && playlistElement.position >= position) {