#!/bin/sh

if [ $# -ne 2 ]
then
    echo "usage: $0 rrdname pngname"
    exit 1
fi
rrdname="${1}"
pngname="${2}"

# Prefixes for rrd and png files. Note that if the prefix is a directory, it must incldue the trailing slash
# If no value is set, the files are located in the current directory when the cgi script runs
rrdprefix=
pngprefix=/tmp/


# Graph dimensions
#graph_height=240
#graph_width=720
graph_height=280
graph_width=840

# Preferred font
font="DejaVuSansMono"

# Latency breakpoints in milliseconds
latency_s0=20
latency_s1=40
latency_s2=80
latency_s3=160
latency_s4=320

# Latency colors
latency_c0="dddddd"
latency_c1="ddbbbb"
latency_c2="d4aaaa"
latency_c3="cc9999"
latency_c4="c38888"
latency_c5="bb7777"

# Standard deviation color & opacity
stddev_c="55333355"

# Loss color
loss_c="ee0000"


gen_graph()
{
    png=$1
    rrd=$2
    start=$3
    end=$4
    step=$5
    description=$6

    echo "<RRD::GRAPH \"${png}\""
        echo "--lazy"
        echo "--start \"${start}\" --end \"${end}\" --step \"${step}\""
        echo "--height ${graph_height} --width ${graph_width}"
        echo "--title \"Average Latency and Packet Loss - ${description}\""
        echo "--disable-rrdtool-tag"
        echo "--color BACK#ffffff"
        echo "--font DEFAULT:9:\"${font}\""
        echo "--font AXIS:8:\"${font}\""

        echo "DEF:latency_us=\"${rrd}\":latency:AVERAGE:step=\"${step}\""
        echo "CDEF:latency=latency_us,1000,/"
        echo "CDEF:latency_s0=latency,${latency_s0},MIN"
        echo "CDEF:latency_s1=latency,${latency_s1},MIN"
        echo "CDEF:latency_s2=latency,${latency_s2},MIN"
        echo "CDEF:latency_s3=latency,${latency_s3},MIN"
        echo "CDEF:latency_s4=latency,${latency_s4},MIN"
        echo "VDEF:latency_min=latency,MINIMUM"
        echo "VDEF:latency_max=latency,MAXIMUM"
        echo "VDEF:latency_avg=latency,AVERAGE"
        echo "VDEF:latency_last=latency,LAST"

        echo "DEF:stddev_us=\"${rrd}\":stddev:AVERAGE:step=\"${step}\""
        echo "CDEF:stddev=stddev_us,1000,/"
        echo "VDEF:stddev_min=stddev,MINIMUM"
        echo "VDEF:stddev_max=stddev,MAXIMUM"
        echo "VDEF:stddev_avg=stddev,AVERAGE"
        echo "VDEF:stddev_last=stddev,LAST"

        echo "DEF:loss=\"${rrd}\":loss:AVERAGE:step=\"${step}\""
        echo "CDEF:loss_neg=loss,-1,*"
        echo "VDEF:loss_min=loss,MINIMUM"
        echo "VDEF:loss_max=loss,MAXIMUM"
        echo "VDEF:loss_avg=loss,AVERAGE"
        echo "VDEF:loss_last=loss,LAST"

        echo "COMMENT:\"                         Min              Max              Avg             Last\n\""

        echo "COMMENT:\"     \""
        echo "AREA:latency#${latency_c5}"
        echo "AREA:latency_s4#${latency_c4}"
        echo "AREA:latency_s3#${latency_c3}"
        echo "AREA:latency_s2#${latency_c2}"
        echo "AREA:latency_s1#${latency_c1}"
        echo "AREA:latency_s0#${latency_c0}"
        echo "LINE1:latency#000000:\"Latency  \""
        echo "GPRINT:\"latency_min:%8.3lf ms\t\""
        echo "GPRINT:\"latency_max:%8.3lf ms\t\""
        echo "GPRINT:\"latency_avg:%8.3lf ms\t\""
        echo "GPRINT:\"latency_last:%8.3lf ms\n\""

        echo "COMMENT:\"     \""
        echo "LINE1:stddev#${stddev_c}:\"Stddev   \""
        echo "GPRINT:\"stddev_min:%8.3lf ms\t\""
        echo "GPRINT:\"stddev_max:%8.3lf ms\t\""
        echo "GPRINT:\"stddev_avg:%8.3lf ms\t\""
        echo "GPRINT:\"stddev_last:%8.3lf ms\n\""

        echo "COMMENT:\"     \""
        echo "AREA:loss_neg#${loss_c}:\"Loss         \""
        echo "GPRINT:\"loss_min:%4.1lf %%\t\t\""
        echo "GPRINT:\"loss_max:%4.1lf %%\t\t\""
        echo "GPRINT:\"loss_avg:%4.1lf %%\t\t\""
        echo "GPRINT:\"loss_last:%4.1lf %%\n\""
        echo "COMMENT:\" \n\""
        echo "GPRINT:\"latency_last:Ending at %H\\:%M on %B %d, %Y\\r:strftime\""

        echo ">"
        echo "<p>"
}

(
    echo "#!/usr/bin/rrdcgi"
    echo "<html> <head> <title>Latency Statistics for ${rrdname}</title> </head> <body>"

    gen_graph "${pngprefix}${pngname}-1.png" "${rrdprefix}${rrdname}.rrd" "now-8h" "now" "60" "Last 8 hours - 1 minute intervals"
    gen_graph "${pngprefix}${pngname}-2.png" "${rrdprefix}${rrdname}.rrd" "now-36h" "now" "300" "Last 36 hours - 5 minute intervals"
    gen_graph "${pngprefix}${pngname}-3.png" "${rrdprefix}${rrdname}.rrd" "now-8d" "now" "1800" "Last 8 days - 30 minute intervals"
    gen_graph "${pngprefix}${pngname}-4.png" "${rrdprefix}${rrdname}.rrd" "now-60d" "now" "14400" "Last 60 days - 4 hour intervals"
    gen_graph "${pngprefix}${pngname}-5.png" "${rrdprefix}${rrdname}.rrd" "now-1y" "now" "86400" "Last 1 year - 1 day intervals"
    gen_graph "${pngprefix}${pngname}-6.png" "${rrdprefix}${rrdname}.rrd" "now-4y" "now" "86400" "Last 4 years - 1 day intervals"

    echo "</body> </html>"
) > "${pngname}.cgi"
