#!/bin/bash

DEVICE=wlan0

good=0
for gooddev in `grep \: /proc/net/dev | awk -F: '{print $1}'`
do
    if [ "$DEVICE" = $gooddev ]
    then
        good=1
        break
    fi
done

if [ $good -eq 0 ]
then
    echo "Change DEVICE in ~/.local/scripts/9993_network"
        grep ":" /proc/net/dev | awk -F: '{print $1}' | sed s@\ @@g
    exit 1
fi

if [ ! -f $HOME/.local/.tmp_RXNET_BIT ]
then
    RXNET_BIT=0
    TXNET_BIT=0

    echo $RXNET_BIT > $HOME/.local/.tmp_RXNET_BIT
    echo $TXNET_BIT > $HOME/.local/.tmp_TXNET_BIT
fi

RXNET_BIT=$(cat $HOME/.local/.tmp_RXNET_BIT)
TXNET_BIT=$(cat $HOME/.local/.tmp_TXNET_BIT)

line=`grep $DEVICE /proc/net/dev | sed s/.*://`
rx=`echo $line | awk '{print $1}'`
tx=`echo $line | awk '{print $9}'`

inbound=$(($rx-$RXNET_BIT))
outbound=$(($tx-$TXNET_BIT))

LASTNETTIME_BIT=$(date +%s)

line=`grep $DEVICE /proc/net/dev | sed s/.*://`
RXNET_BIT=`echo $line | awk '{print $1}'`
TXNET_BIT=`echo $line | awk '{print $9}'`

echo $RXNET_BIT > $HOME/.local/.tmp_RXNET_BIT
echo $TXNET_BIT > $HOME/.local/.tmp_TXNET_BIT

if [ $inbound -gt $((1024*1024)) ]
then
    inb=$(printf "%.2f MB/s" $(echo "scale=2; $inbound / 1024 / 1024" | bc))
elif [ $inbound -gt 1024 ]
then
    inb=$(printf "%.2f KB/s" $(echo "scale=2; $inbound / 1024" | bc))
else
    inb=$(printf "%i B/s" $inbound)
fi

if [ $outbound -gt $((1024*1024)) ]
then
    outb=$(printf "%.2f MB/s" $(echo "scale=2; $outbound / 1024 / 1024" | bc))
elif [ $outbound -gt 1024 ]
then
    outb=$(printf "%.2f KB/s" $(echo "scale=2; $outbound / 1024" | bc))
else
    outb=$(printf "%i B/s" $outbound)
fi

echo "In: $inb  Out: $outb"