Fix the idle-inhibitor script

It turns out that the idle-inhibitor provided by sway only works
with views (application windows), i.e. inhibition cannot be run
on empty workspaces because they do not contain views.
Also, when switching between different workspaces, the views of
the previous workspace may have idle inhibitors, causing inhibition
to be active even if no sound is played until the old views are
updated. To update the old views, it is necessary to switch to the
appropriate workspace and wait for the script to execute, which
will remove the inhibitors that is incorrect and inconvenient.
This patch introduces a new inhibit method based on
systemd-inhibit, which has none of the above problems.

usr/share/sway/scripts/idle-inhibitor.sh

@@ -1,11 +1,32 @@
 #!/bin/bash
 
-set -e
+check_status() {
+  grep -s -l -v "closed" \
+    /proc/asound/card*/pcm*/sub*/status \
+    &>/dev/null
+}
 
-if grep -s -l -v "closed" /proc/asound/card*/pcm*/sub*/status; then
-  swaymsg inhibit_idle open
-  printf "Idle inhibition is ON."
-else
-  swaymsg inhibit_idle none
-  printf "Idle inhibition is OFF."
-fi
+out() {
+  printf "Idle inhibition is OFF.\n"
+  exit 0
+}
+
+watch_status() {
+  printf "Idle inhibition is ON.\n"
+  while check_status; do
+    sleep 10
+  done
+  out
+}
+
+main() {
+  check_status || out
+  test "$1" = "-w" && watch_status
+  systemd-inhibit \
+    --what=idle \
+    --who="${0##*/}" \
+    --why="Inhibit idle due to audio is now playing" \
+    --mode=block \
+    "$0" -w
+}
+main "$@"