#!/usr/bin/env bash
set -euo pipefail

state_dir="${XDG_RUNTIME_DIR:-/tmp}"
if [ ! -w "$state_dir" ]; then
  state_dir="${XDG_CACHE_HOME:-$HOME/.cache}"
  mkdir -p "$state_dir"
fi
if [ ! -w "$state_dir" ]; then
  state_dir="/tmp"
fi
state_file="$state_dir/polybar-awake.state"
action="${1:-toggle}"

export DISPLAY="${DISPLAY:-:0}"
if [ -z "${XAUTHORITY:-}" ] && [ -r "$HOME/.Xauthority" ]; then
  export XAUTHORITY="$HOME/.Xauthority"
fi

notify() {
  if command -v dunstify >/dev/null 2>&1; then
    dunstify -a polybar -u low "Force awake" "$1"
  fi
}

save_current_state() {
  local query
  query="$(xset q)"

  {
    printf 'blanking=%s\n' "$(printf '%s\n' "$query" | awk '/prefer blanking:/ { print $3; exit }')"
    printf 'exposures=%s\n' "$(printf '%s\n' "$query" | awk '/allow exposures:/ { print $6; exit }')"
    printf 'timeout=%s\n' "$(printf '%s\n' "$query" | awk '/timeout:/ { print $2; exit }')"
    printf 'cycle=%s\n' "$(printf '%s\n' "$query" | awk '/timeout:/ { print $4; exit }')"
    printf 'standby=%s\n' "$(printf '%s\n' "$query" | awk '/Standby:/ { print $2; exit }')"
    printf 'suspend=%s\n' "$(printf '%s\n' "$query" | awk '/Standby:/ { print $4; exit }')"
    printf 'off=%s\n' "$(printf '%s\n' "$query" | awk '/Standby:/ { print $6; exit }')"
    printf 'dpms=%s\n' "$(printf '%s\n' "$query" | awk '/DPMS is/ { print $3; exit }')"
  } >"$state_file"
}

enable_awake() {
  if [ ! -f "$state_file" ]; then
    save_current_state
  fi

  xset s noblank
  xset s off
  xset -dpms
  notify "enabled"
}

restore_value() {
  local name="$1"
  local fallback="$2"
  local value

  value="$(awk -F= -v key="$name" '$1 == key { print $2; exit }' "$state_file" 2>/dev/null || true)"
  printf '%s' "${value:-$fallback}"
}

disable_awake() {
  if [ -f "$state_file" ]; then
    local blanking exposures timeout cycle standby suspend off dpms
    blanking="$(restore_value blanking yes)"
    exposures="$(restore_value exposures yes)"
    timeout="$(restore_value timeout 600)"
    cycle="$(restore_value cycle 600)"
    standby="$(restore_value standby 600)"
    suspend="$(restore_value suspend 600)"
    off="$(restore_value off 600)"
    dpms="$(restore_value dpms Enabled)"

    if [ "$blanking" = "yes" ]; then
      xset s blank
    else
      xset s noblank
    fi

    if [ "$exposures" = "yes" ]; then
      xset s expose
    else
      xset s noexpose
    fi

    xset s "$timeout" "$cycle"
    xset dpms "$standby" "$suspend" "$off"

    if [ "$dpms" = "Enabled" ]; then
      xset +dpms
    else
      xset -dpms
    fi

    rm -f "$state_file"
  else
    xset s on
    xset +dpms
  fi

  notify "disabled"
}

case "$action" in
  on)
    enable_awake
    ;;
  off)
    disable_awake
    ;;
  toggle)
    if [ -f "$state_file" ]; then
      disable_awake
    else
      enable_awake
    fi
    ;;
  *)
    notify "unknown action: $action"
    exit 2
    ;;
esac