Refactoring battery status

#!/usr/bin/env bash
##############################
# Battery Status refactoring #
##############################

export DISPLAY=:0.0

get_ac_adapter_status() {
    echo $(acpi -a | cut -d' ' -f3 | cut -d- -f1)
}

get_battery_level() {
    echo $(acpi -b | grep -P -o '[0-9]+(?=%)')
}

notify_user() {
    local message="$1"
    local icon="$2"
    notify-send -u critical "$message" -i "$icon"
}

charge_above_threshold() {
    local threshold="$1"
    while true; do
        AC_ADAPTER=$(get_ac_adapter_status)
        BATTERY_LEVEL=$(get_battery_level)
        if [ "$AC_ADAPTER" == "off" ]; then
            break
        elif [ "$BATTERY_LEVEL" -ge "$threshold" ]; then
            notify_user "Desconecte o adaptador de energia! Nível da bateria: ${BATTERY_LEVEL}% (acima de $threshold%)" "battery-full-charged"
        fi
    done
}

charge_below_threshold() {
    local threshold="$1"
    while true; do
        AC_ADAPTER=$(get_ac_adapter_status)
        BATTERY_LEVEL=$(get_battery_level)
        if [ "$AC_ADAPTER" == "on" ]; then
            break
        elif [ "$BATTERY_LEVEL" -lt "$threshold" ]; then
            notify_user "Conecte o adaptador de energia! Nível da bateria: ${BATTERY_LEVEL}% (abaixo de $threshold%)" "battery-caution"
        fi
    done
}

while true; do
    AC_ADAPTER=$(get_ac_adapter_status)
    BATTERY_LEVEL=$(get_battery_level)

    if [ "$AC_ADAPTER" == "on" ]; then
        charge_above_threshold 75
    else
        charge_below_threshold 25
    fi
done