Get Magic Mouse battery level

mouse_battery.sh

#!/bin/sh

percentage=$( ioreg -rS -c BNBMouseDevice -k BatteryPercent -d 1 | grep BatteryPercent | tail -1 | awk '{print $NF}' )

if [ "$percentage" == "" ]; then
    echo "Disconnected";
else
    if ((50 <= percentage)); then
        color=32; #green
    elif ((20 <= percentage)); then
        color=33; #yellow
    else
        color=31; #red
    fi

    echo "\033[${color}mMouse Battery: ${percentage}%\033[0m"
fi