Clean up the system volume in mode-line display code

2 files changed, 58 insertions, 61 deletions

diff --git a/.emacs.d/init.el b/.emacs.d/init.el
index 94f1ccb..ad9b091 100644
--- a/.emacs.d/init.el
+++ b/.emacs.d/init.el
@@ -1,6 +1,6 @@
 ;;; init.el --- bandali's emacs configuration -*- lexical-binding: t -*-
 
-;; Copyright (C) 2018-2022  Amin Bandali <bandali@gnu.org>
+;; Copyright (c) 2018-2023 Amin Bandali <bandali@gnu.org>
 
 ;; This program is free software: you can redistribute it and/or modify
 ;; it under the terms of the GNU General Public License as published by
@@ -211,47 +211,53 @@
   (display-battery-mode))
 
 (progn ; display system volume in mode-line
-  (defun b/get-volume-level (&optional mic)
-    "Returns the current system sound volume.
-If MIC is non-nil, it returns the microphone volume instead."
-    (string-to-number
-     (string-trim
-      (shell-command-to-string
-       (mapconcat
-        #'identity
-        `("pamixer" ,(when mic "--default-source") "--get-volume")
-        " ")))))
-
-  (defun b/set-volume-level (level &optional mic)
-    "Set the system sound volume to LEVEL.
-If MIC is non-nil, set the volume level for the microphone
-instead."
-    (let ((v (if mic 'b/volume-level-mic 'b/volume-level)))
-      (eval `(setq ,v ,level))))
-
-  (defun b/get-volume-mute (&optional mic)
-    "Returns t if system sound is currently muted.
-If MIC is non-nil, it instead returns t if the microphone is
-muted."
-    (string=
-     "true"
-     (string-trim
-      (shell-command-to-string
-       (mapconcat
-        #'identity
-        `("pamixer" ,(when mic "--default-source") "--get-mute")
-        " ")))))
-
-  (defun b/set-volume-mute (mute &optional mic)
-    "Set the system sound mutedness to MUTE.
-If MIC is non-nil, set the mutedness for the microphone instead."
-    (let ((v (if mic 'b/volume-mute-mic 'b/volume-mute)))
-      (eval `(setq ,v ,mute))))
-
-  (defvar b/volume-level (b/get-volume-level))
-  (defvar b/volume-mute (b/get-volume-mute))
-  (defvar b/volume-level-mic (b/get-volume-level 'mic))
-  (defvar b/volume-mute-mic (b/get-volume-mute 'mic))
+  (defvar b/volume-level 0)
+  (defvar b/volume-mute nil)
+  (defvar b/volume-level-mic 0)
+  (defvar b/volume-mute-mic nil)
+
+  (defun b/volume-get (&optional use-default-source)
+    "Get the default sink volume and mute state.
+If USE-DEFAULT-SOURCE is non-nill, use the default source (e.g. a
+microphone) instead of the default sink."
+    (pcase (split-string   ; expecting: <mute> <volume> (e.g. true 15)
+            (string-trim
+             (shell-command-to-string
+              (mapconcat
+               #'identity
+               `("pamixer"
+                 ,(when use-default-source "--default-source")
+                 "--get-volume"
+                 "--get-mute")
+               " "))))
+      (`(,m ,v)
+       (let ((mute (string= "true" m))
+             (volume (string-to-number v)))
+         `(,mute ,volume)))))
+
+  (defun b/volume-update ()
+    "Update system sound volume as displayed in mode-line."
+    (let ((changed))
+      (pcase (b/volume-get)
+        (`(,mute ,volume)
+         (unless (eq mute b/volume-mute)
+           (setq b/volume-mute mute
+                 changed t))
+         (unless (= volume b/volume-level)
+           (setq b/volume-level volume
+                 changed t))))
+      (pcase (b/volume-get 'mic)
+        (`(,mute ,volume)
+         (unless (eq mute b/volume-mute-mic)
+           (setq b/volume-mute-mic mute
+                 changed t))
+         (unless (= volume b/volume-level-mic)
+           (setq b/volume-level-mic volume
+                 changed t))))
+      (when changed
+        (force-mode-line-update))))
+
+  (defvar b/volume-timer (run-at-time nil 5 #'b/volume-update))
 
   (setq-default
    mode-line-format
diff --git a/.emacs.d/lisp/bandali-exwm.el b/.emacs.d/lisp/bandali-exwm.el
index 4cd2d1c..e7f83ce 100644
--- a/.emacs.d/lisp/bandali-exwm.el
+++ b/.emacs.d/lisp/bandali-exwm.el
@@ -1,6 +1,6 @@
 ;;; bandali-exwm.el --- bandali's EXWM configuration  -*- lexical-binding: t; -*-
 
-;; Copyright (C) 2018-2022  Amin Bandali
+;; Copyright (c) 2018-2023 Amin Bandali
 
 ;; Author: Amin Bandali <bandali@gnu.org>
 ;; Keywords: tools
@@ -182,62 +182,53 @@ around if needed."
                  (interactive)
                  (start-process-shell-command
                   "dmneu-pamixer" nil "dmenu-pamixer")
-                 (b/set-volume-level (b/get-volume-level))
-                 (force-mode-line-update)))
+                 (b/volume-update)))
    ([XF86AudioMute] .             ; borken on my X200 :-(
     (lambda ()
       (interactive)
       (start-process "" nil "pamixer" "--toggle-mute")
-      (b/set-volume-mute (b/get-volume-mute))
-      (force-mode-line-update)))
+      (b/volume-update)))
    ([\s-XF86AudioMute] .            ; toggle mic mute
     (lambda ()
       (interactive)
       (start-process
        "" nil "pamixer" "--default-source" "--toggle-mute")
-      (b/set-volume-mute (b/get-volume-mute 'mic) 'mic)
-      (force-mode-line-update)))
+      (b/volume-update)))
    ([XF86Launch1] .
     (lambda ()
       (interactive)
       (start-process "" nil "pamixer" "--toggle-mute")
-      (b/set-volume-mute (b/get-volume-mute))
-      (force-mode-line-update)))
+      (b/volume-update)))
    ([\s-XF86Launch1] .            ; toggle mic mute
     (lambda ()
       (interactive)
       (start-process
        "" nil "pamixer" "--default-source" "--toggle-mute")
-      (b/set-volume-mute (b/get-volume-mute 'mic) 'mic)
-      (force-mode-line-update)))
+      (b/volume-update)))
    ([XF86AudioLowerVolume] .
     (lambda ()
       (interactive)
       (start-process
        "" nil "pamixer" "--allow-boost" "--decrease" "5")
-      (b/set-volume-level (b/get-volume-level))
-      (force-mode-line-update)))
+      (b/volume-update)))
    ([XF86AudioRaiseVolume] .
     (lambda ()
       (interactive)
       (start-process
        "" nil "pamixer" "--allow-boost" "--increase" "5")
-      (b/set-volume-level (b/get-volume-level))
-      (force-mode-line-update)))
+      (b/volume-update)))
    ([\s-XF86AudioLowerVolume] .
     (lambda ()
       (interactive)
       (start-process
        "" nil "pamixer" "--default-source" "--decrease" "5")
-      (b/set-volume-level (b/get-volume-level 'mic) 'mic)
-      (force-mode-line-update)))
+      (b/volume-update)))
    ([\s-XF86AudioRaiseVolume] .
     (lambda ()
       (interactive)
       (start-process
        "" nil "pamixer" "--default-source" "--increase" "5")
-      (b/set-volume-level (b/get-volume-level 'mic) 'mic)
-      (force-mode-line-update)))
+      (b/volume-update)))
    ([XF86AudioPlay] .
     (lambda ()
       (interactive)