Add a transient map for frequent commands (#84)

Co-authored-by: Daniel Martins <[email protected]>

README.md

@@ -66,9 +66,11 @@ Add the following to the `config.el` file:
 ``` el
 (use-package! smudge
   :bind-keymap ("C-c ." . smudge-command-map)
-  :config
-  (setq smudge-oauth2-client-secret "..."
-        smudge-oauth2-client-id "..."))
+  :custom
+  (smudge-oauth2-client-secret "...")
+  (smudge-oauth2-client-id "...")
+  ;; optional: enable transient map for frequent commands
+  (smudge-player-use-transient-map t))
 ```
 
 ## Configuration
@@ -85,6 +87,14 @@ conventions suggested for minor modes as defined in the Emacs manual
 [Key Binding Conventions](https://www.gnu.org/software/emacs/manual/html_node/elisp/Key-Binding-Conventions.html#Key-Binding-Conventions).
 Previous versions of this package used <kbd>M-p</kbd>.
 
+A transient map can be enabled to allow repeating frequent commands
+(defined in `smudge-transient-command-map`) without having to repeat the
+prefix key for `smudge-command-map`.
+
+```el
+(setq smudge-player-use-transient-map t)
+```
+
 In order to get the client ID and client secret, you need to create a
 [Spotify app](https://developer.spotify.com/my-applications), specifying
 <http://localhost:8080/smudge-api-callback> as the redirect URI (or whichever

smudge-controller.el

@@ -100,6 +100,11 @@ The following placeholders are supported:
   :type 'string
   :group 'smudge)
 
+(defcustom smudge-player-use-transient-map nil
+  "Whether a transient map should be activated after commands that are likely to be repeated."
+  :type 'bool
+  :group 'smudge)
+
 (defvar smudge-controller-timer nil)
 
 (defvar smudge-controller-player-status ""
@@ -108,6 +113,19 @@ The following placeholders are supported:
 (defvar smudge-controller-player-metadata nil
   "The metadata about the currently playing track.")
 
+(defmacro defun-smudge-transient (&rest body)
+  "Create a transient smudge command from BODY.
+
+A transient command allows you to immediately invoke another command from
+`smudge-transient-command-map'. See `set-transient-map'.
+
+The transient map is enabled if `smudge-player-use-transient-map' is non-nil."
+  (declare (doc-string 3)
+           (indent defun))
+  `(defun ,@body
+     (when smudge-player-use-transient-map
+       (set-transient-map smudge-transient-command-map))))
+
 (defun smudge-controller-apply (suffix &rest args)
   "Simple facility to emulate multimethods.
 Apply SUFFIX to smudge-controller-prefixed functions, applying ARGS."
@@ -202,22 +220,22 @@ This corresponds to the current REPEATING state."
   (interactive)
   (smudge-controller-apply "player-toggle-play"))
 
-(defun smudge-controller-next-track ()
+(defun-smudge-transient smudge-controller-next-track ()
   "Sends a `next track' command to Spotify process."
   (interactive)
   (smudge-controller-apply "player-next-track"))
 
-(defun smudge-controller-previous-track ()
+(defun-smudge-transient smudge-controller-previous-track ()
   "Sends a `previous track' command to Spotify process."
   (interactive)
   (smudge-controller-apply "player-previous-track"))
 
-(defun smudge-controller-volume-up ()
+(defun-smudge-transient smudge-controller-volume-up ()
   "Increase the volume for the active device."
   (interactive)
   (smudge-controller-apply "volume-up"))
 
-(defun smudge-controller-volume-down ()
+(defun-smudge-transient smudge-controller-volume-down ()
   "Increase the volume for the active device."
   (interactive)
   (smudge-controller-apply "volume-down"))

smudge.el

@@ -157,6 +157,15 @@ Prompt for the NAME and whether it should be made PUBLIC."
 
 (fset 'smudge-command-map smudge-command-map)
 
+(defvar smudge-transient-command-map
+  (let ((map (make-sparse-keymap)))
+    (define-key map (kbd "M-b") #'smudge-controller-previous-track)
+    (define-key map (kbd "M-f") #'smudge-controller-next-track)
+    (define-key map (kbd "M-u") #'smudge-controller-volume-up)
+    (define-key map (kbd "M-d") #'smudge-controller-volume-down)
+    map)
+  "Transient keymap for commands that are likely to be repeated.")
+
 (easy-menu-add-item nil '("Tools")
                     '("Smudge"
                       ["Play/Pause"     smudge-controller-toggle-play    :active global-smudge-remote-mode]