#!/bin/bash

interface=$(ip -o -4 route show to default | awk '{print $5}')

nic_in=$(grep $interface /proc/net/dev | awk '{print $2}')
nic_out=$(grep $interface /proc/net/dev | awk '{print $10}')

function human_readable {
        VALUE=$1
        if ! [[ "$VALUE" =~ ^[0-9]+$ ]]; then
                echo "0B"
                return
        fi
        BIGGIFIERS=( B Kb Mb Gb )
        CURRENT_BIGGIFIER=0
        while [ $VALUE -gt 10000 ] ;do
                VALUE=$(($VALUE/1000))
                CURRENT_BIGGIFIER=$((CURRENT_BIGGIFIER+1))      
        done
        echo "$VALUE${BIGGIFIERS[$CURRENT_BIGGIFIER]}"
}

system_ip=$(hostname -I)

echo
echo "Network information:"
printf "System IP:\t%s\n" $system_ip
printf "Traffic in:\t%s\tTraffic out:\t%s\n" `human_readable $nic_in` `human_readable $nic_out`
echo