nix-files/hosts/common/programs/sane-input-handler/sane-input-handler

#!/usr/bin/env nix-shell
#!nix-shell -i bash -p coreutils -p killall -p playerctl -p procps -p sane-open-desktop -p sway -p util-linux -p wireplumber

# input map considerations
# - using compound actions causes delays.
#   e.g. if volup->volup is a distinct action from volup, then single-volup action is forced to wait the maximum button delay.
# - actions which are to be responsive should therefore have a dedicated key.
# - a dedicated "kill" combo is important for unresponsive fullscreen apps, because appmenu doesn't show in those
#   - although better may be to force appmenu to show over FS apps
# - bonsai mappings are static, so buttons can't benefit from non-compounding unless they're mapped accordingly for all lock states
#   - this limitation could be removed, but with work
#
# example of a design which considers these things:
# - when unlocked:
#   - volup toggle  -> app menu
#   - voldown press -> keyboard
#   - voldown hold  -> terminal
#   - power x2      -> screenoff
#   - hold power    -> kill app
# - when locked:
#   - volup tap     -> volume up
#   - volup hold    -> media seek forward
#   - voldown tap   -> volume down
#   - voldown hold  -> media seek backward
#   - power x1      -> screen on
#   - power x2      -> play/pause media
# some trickiness allows for media controls in unlocked mode:
#   - volup tap     -> enter media mode
#     - i.e. in this state, vol tap/hold is mapped to volume/seek
#     - if, after entering media mode, no more taps occur, then we trigger the default app-menu action
# limitations/downsides:
# - power mappings means phone is artificially slow to unlock.
# - media controls when unlocked have quirks:
#   - mashing voldown to decrease the volume will leave you with a toggled keyboard.
#   - seeking backward isn't possible except by first tapping volup.


# increments to use for volume adjustment (in %)
VOL_INCR=5
KEYBOARD="${KEYBOARD:-wvkbd-mobintl}"

action="$1"

isTouchOn() {
  # success if all touch inputs have their events enabled
  swaymsg -t get_inputs --raw \
    | jq --exit-status '. | map(select(.type == "touch")) | all(.libinput.send_events == "enabled")' \
    > /dev/null
}
isScreenOn() {
  # success if all outputs have power
  swaymsg -t get_outputs --raw \
    | jq --exit-status '. | all(.power)' \
    > /dev/null
}

isAllOn() {
  isTouchOn && isScreenOn
}

isInhibited() {
  pidof rofi
}


ignore() {
  true
}
inhibited() {
  true
}
unmapped() {
  true
}

allOn() {
  swaymsg -- output '*' power true
  swaymsg -- input type:touch events enabled
}
allOff() {
  swaymsg -- output '*' power false
  swaymsg -- input type:touch events disabled
}

toggleKeyboard() {
  local kbpid=$(pidof "$KEYBOARD")
  if [ -z "$kbpid" ] || ! ( env kill -s RTMIN+0 "$kbpid" ); then
    echo "sane-input-handler: failed to toggle keyboard: $KEYBOARD"
  fi
}

handleWith() {
  state=
  if [ -n "$_isInhibited" ]; then
    state="inhibited+"
  fi
  if [ -n "$_isAllOn" ]; then
    state="${state}on"
  else
    state="${state}off"
  fi
  echo "sane-input-handler: state=$state action=$action: handleWith: $@"
  "$@"
  exit 0
}

dispatchDefault() {
  case "$action" in
    "powerbutton_one")
      # power once => unlock
      handleWith allOn
      ;;
    "powerbutton_two")
      # power twice => screenoff
      handleWith allOff
      ;;
    # powerbutton_three: intentional no-op because overloading the kill-window handler is risky

    volup_tap*|modal_volup_tap*)
      handleWith wpctl set-volume @DEFAULT_AUDIO_SINK@ "$VOL_INCR"%+
      ;;
    voldown_tap*|modal_voldown_tap*)
      handleWith wpctl set-volume @DEFAULT_AUDIO_SINK@ "$VOL_INCR"%-
      ;;

    volup_hold*|modal_volup_hold*)
      handleWith playerctl position 30+
      ;;
    voldown_hold*|modal_voldown_hold*)
      handleWith playerctl position 10-
      ;;
  esac
}

dispatchOff() {
  case "$action" in
    "powerbutton_two")
      # power twice => toggle media player
      handleWith playerctl play-pause
      ;;
    "powerhold")
      # power toggle during deep sleep often gets misread as power hold, so treat same
      handleWith allOn
      ;;
  esac
}

dispatchOn() {
  case "$action" in
    # powerbutton_one: intentional default to no-op
    # powerbutton_two: intentional default to screenoff
    "powerhold")
      # power thrice: kill active window
      # TODO: disable this if locked (with e.g. schlock, swaylock, etc)
      handleWith swaymsg kill
      ;;
    "powerbutton_volup")
      # power (tap) -> volup: rotate CCW
      handleWith swaymsg -- output '-' transform 90 anticlockwise
      ;;
    "powerbutton_voldown")
      # power (tap) -> voldown: rotate CW
      handleWith swaymsg -- output '-' transform 90 clockwise
      ;;

    "volup_tap_1")
      # swallow: this could be the start to a media control (multi taps / holds),
      # or it could be just a single tap -> release, handled next/below
      handleWith ignore
      ;;
    "volup_1")
      # volume up once: system menu
      handleWith sane-open-desktop rofi.desktop
      ;;

    "voldown_start")
      # volume down once: toggle keyboard
      handleWith toggleKeyboard
      ;;
    "voldown_hold_2")
      # hold voldown to launch terminal
      # note we already triggered the keyboard; that's fine: usually keyboard + terminal go together :)
      # voldown_hold_1 frequently triggers during short taps meant only to reveal the keyboard,
      # so prefer a longer hold duration
      handleWith sane-open-desktop xdg-terminal-exec.desktop
      ;;
    "voldown_tap_1")
      # swallow, to prevent keyboard from also triggering media controls
      handleWith ignore
      ;;
    voldown_hold_*)
      # swallow, to prevent terminal from also triggering media controls
      handleWith ignore
      ;;
  esac
}

dispatchInhibited() {
  case "$action" in
    "powerhold")
      # power thrice: escape hatch in case rofi has hung
      handleWith killall -9 rofi
      ;;
    *)
      # eat everything else (and let rofi consume it)
      handleWith inhibited
      ;;
  esac
}

_isAllOn="$(isAllOn && echo 1 || true)"

if [ -z "$_isAllOn" ]; then
  dispatchOff
else
  _isInhibited="$(isInhibited && echo 1 || true)"
  if [ -n "$_isInhibited" ]; then
    dispatchInhibited
  else
    dispatchOn
  fi
fi

dispatchDefault

handleWith unmapped