Use Shift+Left/Right to switch video chapters

src/actions.js

@@ -22,5 +22,13 @@ var actions = {
     prev_track: {
         run: (window) => window.child.player.playlistWidget.prevTrack(),
         accels: ['<Ctrl>Left'],
+    },
+    next_chapter: {
+        run: (window) => window.child.player.next_chapter(),
+        accels: ['<Shift>Right'],
+    },
+    prev_chapter: {
+        run: (window) => window.child.player.prev_chapter(),
+        accels: ['<Shift>Left'],
     }
 };

src/player.js

@@ -369,6 +369,16 @@ class ClapperPlayer extends GstClapper.Clapper
         this[action]();
     }
 
+    next_chapter()
+    {
+        return this._switchChapter(false);
+    }
+
+    prev_chapter()
+    {
+        return this._switchChapter(true);
+    }
+
     emitWs(action, value)
     {
         if(!this.webserver)
@@ -409,6 +419,30 @@ class ClapperPlayer extends GstClapper.Clapper
         }
     }
 
+    _switchChapter(isPrevious)
+    {
+        if(this.state === GstClapper.ClapperState.STOPPED)
+            return false;
+
+        const { chapters } = this.widget.root.child.controls;
+        if(!chapters)
+            return false;
+
+        const now = this.position / Gst.SECOND;
+        let chapterTimes = Object.keys(chapters);
+        if(isPrevious)
+            chapterTimes.reverse();
+
+        const chapter = chapterTimes.find(time => (isPrevious)
+            ? now - 2.5 > time
+            : now < time
+        );
+        if(!chapter)
+            return false;
+
+        this.seek_chapter(chapter);
+    }
+
     _addPlaylistItems(playlist)
     {
         for(let source of playlist) {