From 20b58f4d603c55b1aba42cc375a97b8708f725ba Mon Sep 17 00:00:00 2001
From: Amin Bandali <bandali@gnu.org>
Date: Sun, 8 Jan 2023 10:28:25 -0500
Subject: [PATCH] * .emacs.d/init.el: Show system volumes in mode-line.

Uses pamixer to get or set the output (speakers or headphones) and
input (microphone) volumes.
---
 .emacs.d/init.el              | 55 +++++++++++++++++++++++++++++++++++
 .emacs.d/lisp/bandali-exwm.el | 47 +++++++++++++++++++++++++-----
 2 files changed, 95 insertions(+), 7 deletions(-)

diff --git a/.emacs.d/init.el b/.emacs.d/init.el
index d9ec432..94f1ccb 100644
--- a/.emacs.d/init.el
+++ b/.emacs.d/init.el
@@ -210,6 +210,61 @@
   (setq battery-mode-line-format " [%p%% %t]")
   (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))
+
+  (setq-default
+   mode-line-format
+   (append
+    mode-line-format
+    '((:eval
+       (format
+        " [%s%%%%%s %s%%%%%s]"
+        (number-to-string b/volume-level)
+        (if b/volume-mute "-" "+")
+        (number-to-string b/volume-level-mic)
+        (if b/volume-mute-mic "-" "+")))))))
+
 ;; (with-eval-after-load 'fringe
 ;;   ;; smaller fringe
 ;;   (fringe-mode '(3 . 1)))
diff --git a/.emacs.d/lisp/bandali-exwm.el b/.emacs.d/lisp/bandali-exwm.el
index 3072765..4cd2d1c 100644
--- a/.emacs.d/lisp/bandali-exwm.el
+++ b/.emacs.d/lisp/bandali-exwm.el
@@ -181,30 +181,63 @@ around if needed."
    ([?\s-\;] . (lambda ()
                  (interactive)
                  (start-process-shell-command
-                  "dmneu-pamixer" nil "dmenu-pamixer")))
+                  "dmneu-pamixer" nil "dmenu-pamixer")
+                 (b/set-volume-level (b/get-volume-level))
+                 (force-mode-line-update)))
    ([XF86AudioMute] .             ; borken on my X200 :-(
     (lambda ()
       (interactive)
-      (start-process "" nil "pamixer" "--toggle-mute")))
+      (start-process "" nil "pamixer" "--toggle-mute")
+      (b/set-volume-mute (b/get-volume-mute))
+      (force-mode-line-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)))
    ([XF86Launch1] .
     (lambda ()
       (interactive)
-      (start-process "" nil "pamixer" "--toggle-mute")))
+      (start-process "" nil "pamixer" "--toggle-mute")
+      (b/set-volume-mute (b/get-volume-mute))
+      (force-mode-line-update)))
    ([\s-XF86Launch1] .            ; toggle mic mute
     (lambda ()
       (interactive)
       (start-process
-       "" nil "pamixer" "--default-source" "--toggle-mute")))
+       "" nil "pamixer" "--default-source" "--toggle-mute")
+      (b/set-volume-mute (b/get-volume-mute 'mic) 'mic)
+      (force-mode-line-update)))
    ([XF86AudioLowerVolume] .
     (lambda ()
       (interactive)
       (start-process
-       "" nil "pamixer" "--allow-boost" "--decrease" "5")))
+       "" nil "pamixer" "--allow-boost" "--decrease" "5")
+      (b/set-volume-level (b/get-volume-level))
+      (force-mode-line-update)))
    ([XF86AudioRaiseVolume] .
     (lambda ()
       (interactive)
       (start-process
-       "" nil "pamixer" "--allow-boost" "--increase" "5")))
+       "" nil "pamixer" "--allow-boost" "--increase" "5")
+      (b/set-volume-level (b/get-volume-level))
+      (force-mode-line-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)))
+   ([\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)))
    ([XF86AudioPlay] .
     (lambda ()
       (interactive)
@@ -319,7 +352,7 @@ around if needed."
     '((:eval
        (format
         " [%s]" (number-to-string
-                exwm-workspace-current-index)))))))
+                 exwm-workspace-current-index)))))))
 
 (with-eval-after-load 'exwm-layout
   (setq exwm-layout-show-all-buffers t))
-- 
2.20.1