Plotter

#!/bin/bash
term=${1:-wxt}
if [[ $term =~ ^- ]]; then
    echo "Usage: ${0##*/} TERM"
    echo "Example TERM:"
    echo '"wxt": gtk'
    echo '(buggy) "x11": x11 (Examine man gnuplot for custom color scheme. Problematic with constant raising.)'
    echo '"dumb": plain text'
    exit
fi

shopt -s nullglob
IFS=$'\n\t ' #make \n first for "*" expansion which uses the first character.

tput civis
gpfile=/dev/shm/plotter_file_$$
trap "rm $gpfile; tput cnorm; exit" INT TERM

function updatedata() {
    #DOWN
    totaldown=0
    for network in /sys/class/net/{eth,wlan}*/statistics/rx_bytes; do
        read network < $network
        (( totaldown+=network ))
    done
    (( oldtotaldown != 0 )) && DOWN=$(( (totaldown - oldtotaldown) /1024)) || DOWN=0
    oldtotaldown=$totaldown

    #UP
    totalup=0
    for network in /sys/class/net/{eth,wlan}*/statistics/tx_bytes; do
        read network < $network
        (( totalup+=network ))
    done
    (( oldtotalup != 0 )) && UP=$(( (totalup - oldtotalup) /1024)) || UP=0
    oldtotalup=$totalup

    #CPU
    read cpu a b c idle rest < /proc/stat
    total=$((a+b+c+idle))
    intervaltotal=$((total-prevtotal))
    (( prevtotal != 0 )) && CPU=$((100* ( intervaltotal - (idle - previdle) ) / intervaltotal)) || CPU=0
    prevtotal=$total
    previdle=$idle

    #MEM
    while read type size kb; do
        [[ $type == MemTotal: ]] && total=$size && used=$total
        [[ $type =~ (MemFree|Buffers|Cached): ]] && ((used-=size))
    done < /proc/meminfo
    MEM=$(( (100 * used) / total))
}

#Configure $TITLE
function updatetitle() {
    DAY=$(date +%a)
    TIME=$(date +"%H:%M")
    DATE=$(date +"%b %d")
    TITLE="($DAY) $TIME ($DATE)"
}

function updatetics() {
    now=$(date +"%H:%M:%S" -d "10 seconds")
    minuteago=$(date +"%H:%M:%S" -d "50 seconds ago")
}
if [[ $term == dumb ]]; then
    color=31
    sedcolorizer=$(
    for drawing in '*' '#' '$' '%'; do
        echo "s/\\$drawing\+/\\x1b[$((color++))m&\\x1b[m/g"
    done
    echo "s/[|+]\+\( [0-9]*\)*$/\\x1b[33m&\\x1b[m/"
    )
fi
counter=0
minuteago=$(date +"%H:%M:%S")
now=$(date +"%H:%M:%S" -d "1 minute")

sleep 0.$((1000000000 - $(date +%-N) ))s
{
    [[ $term != dumb ]] && echo "set term $term noraise title 'Gnuplot$$'"

    echo 'set grid'

    echo 'set logscale y'
#   echo 'set ytics 0,250'
    echo 'unset mytics'

    echo 'set y2tics 0,25'


    while [[ $term == dumb ]] || [[ $counter = 0 ]] || wmctrl -l | grep -q Gnuplot$$; do
        [[ $term = dumb ]] && echo "set term dumb $(($(tput cols)+7)) $(($(tput lines)+2))"
        #reset axes every time, because you can zoom-in without zooming-out (X11)
        echo 'set xrange[0:60]'
        echo 'set yrange[1:2000]'
        echo 'set y2range[0:100]'

        #update x-axis every 10 seconds
        if (( ++counter == 61 )); then
            updatecounter=9
            while (( ++updatecounter != 61 )); do
                data[$((updatecounter-10))]=${data[$updatecounter]}
                unset "data[$updatecounter]"
            done
            updatetics
            (( counter-=10 ))
        fi
        echo "set xtics ('$minuteago' 0, '' 10, '' 20, '' 30, '' 40, '' 50, '$now' 60)"

        #gather and print data to temporary file
        updatedata
        printf -v "data[$counter]" "%s\t" $UP $DOWN $CPU $MEM
        echo "${data[*]}" > $gpfile

        updatetitle
        echo "set title '$TITLE'"

        echo "plot  '$gpfile'   using 1 title 'Upload' with lines, \
                '$gpfile'   using 2 title 'Download' with lines, \
                '$gpfile'   using 3 title 'CPU' axes x1y2 with lines, \
                '$gpfile'   using 4 title 'MEM' axes x1y2 with lines"

        #sleep to about the whole second
        sleep 0.$((1000000000 - $(date +%-N) ))s
    done
} | gnuplot | { [[ $term = dumb ]] && sed -e "$sedcolorizer" -e 's/^  //;/^$/d'; }

rm $gpfile
tput cnorm