Add functionality to add songs to the queue (#93)

README.md

@@ -216,6 +216,7 @@ key bindings:
 | <kbd>a</kbd>     | Adds track to a playlist                                         |
 | <kbd>l</kbd>     | Loads the next page of results (pagination)                      |
 | <kbd>g</kbd>     | Clears the results and reloads the first page of results         |
+| <kbd>k</kbd>     | Adds track to the queue                                          |
 | <kbd>M-RET</kbd> | Plays the track under the cursor in the context of its album [1] |
 
 [1] D-Bus implementation for GNU/Linux do not support passing the context, so
@@ -285,6 +286,7 @@ bindings in the resulting buffer:
 | <kbd>g</kbd>     | Clears the results and reloads the first page of results            |
 | <kbd>f</kbd>     | Follows the current playlist                                        |
 | <kbd>u</kbd>     | Unfollows the current playlist                                      |
+| <kbd>k</kbd>     | Adds track to the queue                                             |
 | <kbd>M-RET</kbd> | Plays the track under the cursor in the context of the playlist [1] |
 
 Both buffers load the `global-smudge-remote-mode` by default.

smudge-api.el

@@ -596,5 +596,31 @@ Call CALLBACK if provided."
    nil
    callback))
 
+
+(defun smudge-api-queue-add-track (track-id &optional callback)
+  "Add given TRACK-ID to the queue"
+  (smudge-api-call-async
+   "POST"
+   (concat "/me/player/queue?"
+	   (url-build-query-string `((uri ,track-id))
+				   nil t))
+   nil
+   callback)
+)
+(defun smudge-api-queue-add-tracks (track-ids &optional callback)
+  "Add given TRACK-IDs to the queue"
+  ;; Spotify's API doesn't provide a endpoint that would enable us to
+  ;; add multiple tracks to the queue at the same time.
+  ;; Thus we have to synchronously add the tracks
+  ;; one by one to the queue.
+  (if (car track-ids)
+    (smudge-api-queue-add-track (car track-ids)
+		  (lambda (response)
+		    (smudge-api-queue-add-tracks (cdr track-ids)
+						 nil)))
+    (funcall callback)
+  )
+)
+
 (provide 'smudge-api)
 ;;; smudge-api.el ends here

smudge-track.el

@@ -27,6 +27,7 @@
     (define-key map (kbd "g")     #'smudge-track-reload)
     (define-key map (kbd "f")     #'smudge-track-playlist-follow)
     (define-key map (kbd "u")     #'smudge-track-playlist-unfollow)
+    (define-key map (kbd "k")     #'smudge-track-add-to-queue)
     map)
   "Local keymap for `smudge-track-search-mode' buffers.")
 
@@ -284,5 +285,18 @@ Default to sortin tracks by number when listing the tracks from an album."
            (lambda (_)
              (message "Song added.")))))))))
 
+(defun smudge-track-add-to-queue ()
+  "Add the track under the cursor to the queue."
+  (interactive)
+  (let ((selected-track (tabulated-list-get-id)))
+    (let ((track-id (smudge-api-get-item-uri selected-track)))
+      (smudge-api-queue-add-track
+       track-id
+       (lambda(_)
+	 (message (format "Added \"%s\" to your queue." (smudge-api-get-item-name selected-track)))))
+  ))
+)
+
+
 (provide 'smudge-track)
 ;;; smudge-track.el ends here