round() { awk -v n=$1 -v d=$2 'BEGIN{print int((n+d/2)/d) * d}'; }

# e.g. 69.420%
percentage_raw=$(upower -i /org/freedesktop/UPower/devices/DisplayDevice | awk '/percentage:/ {print $2}')
# e.g. 7h
est_time=$(upower -i /org/freedesktop/UPower/devices/DisplayDevice | awk '/time to empty:/ {print $4substr($5, 1, 1)}')

# charging / discharging / pending-charge
chg_state=$(upower -i /org/freedesktop/UPower/devices/DisplayDevice | awk '/state:/ {print $2}')

# rounded to tens: 10 20 30 etc.
percentage_10s=$(round "${percentage_raw%%%}" 10); 

# when battery is low, highlight it
if [[ $percentage_10s -le "10" ]]; then 
	printf "#[[bg=red,fg=brightwhite]]";
elif [[ $percentage_10s -le "20" ]]; then
	printf "#[[bg=brightyellow]]";
fi

printf " ";
if [[ $chg_state == "charging" ]]; then
	printf "󰂄"
else
	if [[ $percentage_10s -le "10" ]]; then printf "󰁺"; fi
	if [[ $percentage_10s -eq "20" ]]; then printf "󰁻"; fi
	if [[ $percentage_10s -eq "30" ]]; then printf "󰁼"; fi
	if [[ $percentage_10s -eq "40" ]]; then printf "󰁽"; fi
	if [[ $percentage_10s -eq "50" ]]; then printf "󰁾"; fi
	if [[ $percentage_10s -eq "60" ]]; then printf "󰁿"; fi
	if [[ $percentage_10s -eq "70" ]]; then printf "󰂀"; fi
	if [[ $percentage_10s -eq "80" ]]; then printf "󰂁"; fi
	if [[ $percentage_10s -eq "90" ]]; then printf "󰂂"; fi
	if [[ $percentage_10s -eq "100" ]]; then printf "󰁹"; fi
fi

printf " ";
# percentage level rounded to a whole number (69%)
printf "%.0f%%" "${percentage_raw%%%}";
if [[ $est_time ]]; then
	printf " ";
	# estimated time, if on battery
	printf " $est_time"
fi
printf " ";
# reset style
printf "#[default]";