# no need for shebang - this file is loaded from charts.d.plugin

# netdata
# real-time performance and health monitoring, done right!
# (C) 2016 Costa Tsaousis <costa@tsaousis.gr>
# GPL v3+
#

# _update_every is a special variable - it holds the number of seconds
# between the calls of the _update() function
ap_update_every=
ap_priority=6900

declare -A ap_devs=()

# _check is called once, to find out if this chart should be enabled or not
ap_check() {
	require_cmd iw || return 1

	local ev=$(run iw dev | awk '
		BEGIN {
			i = "";
			ssid = "";
			ap = 0;
		}
		/^[ \t]+Interface / {
			if( ap == 1 ) {
				print "ap_devs[" i "]=\"" ssid "\""
			}

			i = $2;
			ssid = "";
			ap = 0;
		}
		/^[ \t]+ssid / { ssid = $2; }
		/^[ \t]+type AP$/ { ap = 1; }
		END {
			if( ap == 1 ) {
				print "ap_devs[" i "]=\"" ssid "\""
			}
		}
	')
	eval "${ev}"

	# this should return:
	#  - 0 to enable the chart
	#  - 1 to disable the chart

	[ ${#ap_devs[@]} -gt 0 ] && return 0
	error "no devices found in AP mode, with 'iw dev'"
	return 1
}

# _create is called once, to create the charts
ap_create() {
	local ssid dev

	for dev in "${!ap_devs[@]}"
	do
		ssid="${ap_devs[${dev}]}"

		# create the chart with 3 dimensions
		cat <<EOF
CHART ap_clients.${dev} '' "Connected clients to ${ssid} on ${dev}" "clients" ${dev} ap.clients line $((ap_priority + 1)) $ap_update_every
DIMENSION clients '' absolute 1 1

CHART ap_bandwidth.${dev} '' "Bandwidth for ${ssid} on ${dev}" "kilobits/s" ${dev} ap.net area $((ap_priority + 2)) $ap_update_every
DIMENSION received '' incremental 8 1024
DIMENSION sent '' incremental -8 1024

CHART ap_packets.${dev} '' "Packets for ${ssid} on ${dev}" "packets/s" ${dev} ap.packets line $((ap_priority + 3)) $ap_update_every
DIMENSION received '' incremental 1 1
DIMENSION sent '' incremental -1 1

CHART ap_issues.${dev} '' "Transmit Issues for ${ssid} on ${dev}" "issues/s" ${dev} ap.issues line $((ap_priority + 4)) $ap_update_every
DIMENSION retries 'tx retries' incremental 1 1
DIMENSION failures 'tx failures' incremental -1 1

CHART ap_signal.${dev} '' "Average Signal for ${ssid} on ${dev}" "dBm" ${dev} ap.signal line $((ap_priority + 5)) $ap_update_every
DIMENSION signal 'average signal' absolute 1 1000

CHART ap_bitrate.${dev} '' "Bitrate for ${ssid} on ${dev}" "Mbps" ${dev} ap.bitrate line $((ap_priority + 6)) $ap_update_every
DIMENSION receive '' absolute 1 1000
DIMENSION transmit '' absolute -1 1000
DIMENSION expected 'expected throughput' absolute 1 1000
EOF
	done

	return 0
}

# _update is called continuously, to collect the values
ap_update() {
	# the first argument to this function is the microseconds since last update
	# pass this parameter to the BEGIN statement (see bellow).

	# do all the work to collect / calculate the values
	# for each dimension
	# remember: KEEP IT SIMPLE AND SHORT

	for dev in "${!ap_devs[@]}"
	do
	    echo
	    echo "DEVICE ${dev}"
		iw ${dev} station dump
	done | awk "
        function zero_data() {
            dev = \"\";
            c = 0;
            rb = 0;
            tb = 0;
            rp = 0;
            tp = 0;
            tr = 0;
            tf = 0;
            tt = 0;
            rt = 0;
            s = 0;
            g = 0;
            e = 0;
        }
        function print_device() {
            if(dev != \"\" && length(dev) > 0) {
                print \"BEGIN ap_clients.\" dev;
                print \"SET clients = \" c;
                print \"END\";
                print \"BEGIN ap_bandwidth.\" dev;
                print \"SET received = \" rb;
                print \"SET sent = \" tb;
                print \"END\";
                print \"BEGIN ap_packets.\" dev;
                print \"SET received = \" rp;
                print \"SET sent = \" tp;
                print \"END\";
                print \"BEGIN ap_issues.\" dev;
                print \"SET retries = \" tr;
                print \"SET failures = \" tf;
                print \"END\";

                if( c == 0 ) c = 1;
                print \"BEGIN ap_signal.\" dev;
                print \"SET signal = \" int(s / c);
                print \"END\";
                print \"BEGIN ap_bitrate.\" dev;
                print \"SET receive = \" int(rt / c);
                print \"SET transmit = \" int(tt / c);
                print \"SET expected = \" int(e / c);
                print \"END\";
            }
            zero_data();
        }
        BEGIN {
            zero_data();
        }
        /^DEVICE / {
            print_device();
            dev = \$2;
        }
        /^Station/            { c++; }
        /^[ \\t]+rx bytes:/   { rb += \$3; }
        /^[ \\t]+tx bytes:/   { tb += \$3; }
        /^[ \\t]+rx packets:/ { rp += \$3; }
        /^[ \\t]+tx packets:/ { tp += \$3; }
        /^[ \\t]+tx retries:/ { tr += \$3; }
        /^[ \\t]+tx failed:/  { tf += \$3; }
        /^[ \\t]+signal:/     { x = \$2; s  += x * 1000; }
        /^[ \\t]+rx bitrate:/ { x = \$3; rt += x * 1000; }
        /^[ \\t]+tx bitrate:/ { x = \$3; tt += x * 1000; }
        /^[ \\t]+expected throughput:(.*)Mbps/ {
            x=\$3;
            sub(/Mbps/, \"\", x);
            e += x * 1000;
        }
        END {
            print_device();
        }
    "

	return 0
}