Allow org-yt-open to use emms' or mpv'

README.org

@@ -2605,14 +2605,24 @@ The listings below implement four groups of =org-link= types:
                              :export #'org-yt-export)
 
     (defun org-yt-open (path prefix)
-      "Open an \"yt\" link."
-      (let* ((url (format "https:%s" path))
-             (display-buffer-alist
-              `((,shell-command-buffer-name-async . (display-buffer-no-window)))))
-        (if (and prefix (executable-find "mpv"))
-            (browse-url url)
-          (async-shell-command (format "mpv \"%s\"" url))
-          (message "Launched mpv with \"%s\"" url))))
+      "Open PATH with \"emms\", \"mpv\", or `browse-url' (when PREFIX)."
+      (let ((url (format "https:%s" path)))
+        (cond
+         (prefix
+          (browse-url url))
+         ((require 'emms nil 'noerror)
+          (emms-add-url url)
+          (with-current-emms-playlist
+            (save-excursion
+              (emms-playlist-last)
+              (emms-playlist-mode-play-current-track))) )
+         ((executable-find "mpv")
+          (let ((display-buffer-alist
+                 `((,shell-command-buffer-name-async . (display-buffer-no-window)))))
+            (async-shell-command (format "\"%s\" \"%s\"" url)))
+          (message "Launched mpv with \"%s\"" url))
+         (t
+          (user-error "Can't open `%s': install `emms' and/or `mpv'" url)))))
 
     (defun org-yt-export (path desc backend _)
       "Export an \"yt\" link."