feat: mute 'astyanax' speakers when disconnecting AC

modules/audio-automation/default.nix

@@ -0,0 +1,17 @@
+{ pkgs, ... }:
+
+{
+  environment.systemPackages = [ pkgs.libnotify ];
+
+  services.udev.extraRules = ''
+    SUBSYSTEM=="power_supply", ATTR{online}=="0", ACTION=="change", TAG+="systemd", ENV{SYSTEMD_USER_WANTS}+="mute-audio.service"
+  '';
+
+  systemd.user.services.mute-audio = {
+    description = "mute audio when switching to battery power";
+    serviceConfig = {
+      Type = "oneshot";
+      ExecStart = "${pkgs.bash}/bin/bash -c '${pkgs.pulseaudio}/bin/pactl set-sink-mute $(${pkgs.pulseaudio}/bin/pactl get-default-sink) true && ${pkgs.libnotify}/bin/notify-send \"audio Muted\" \"switched to battery power\"'";
+    };
+  };
+}