#!/usr/bin/env bash

total="$(free -m | grep Mem | awk '{ print $2 }')"
used="$(free -m | grep Mem | awk '{ print $3 }')"
free=$(expr $total - $used)

total_human=$(numfmt --to=iec --format="%.1f" $(( $total * 1000 * 1000 )))
used_human=$(numfmt --to=iec --format="%.1f" $(( $used * 1000 * 1000 )))
free_human=$(numfmt --to=iec --format="%.1f" $(( $free * 1000 * 1000 )))

if [ "$1" = "total" ]; then
    echo $total_human
elif [ "$1" = "used" ]; then
    echo $used_human
elif [ "$1" = "free" ]; then
    echo $free_human
elif [ "$1" = "json" ]; then
    jo total=$total_human used=$used_human free=$free_human
fi