#!/bin/sh

PROGRAM_DIR="`dirname \"$0\"`"
. "$PROGRAM_DIR/utils.sh"
load_config_file "$PROGRAM_DIR/performance-monitor.cfg"
load_config_file /etc/performance-monitor.cfg

interval=5
while getopts i:I:n: c
do case "$c" in
	i)
		interval="$OPTARG"
		;;
	I)
		HOSTNAME="`get_ip_address \"$OPTARG\"`"
		if [ -z "$HOSTNAME" ]; then
			printf "Cannot get IP address from interface '%s'\\n" "$OPTARG" 1>&2
			exit 1
		fi
		;;
	n)
		HOSTNAME="$1"
		;;
	\?)
		printf "Usage: %s [-i <interval>] [-I <interface>] [-n <hostname>]\\n" "$0" 1>&2
		exit 255
		;;
esac done
[ -z "$HOSTNAME" ] && HOSTNAME="`hostname`"

count=0
while true; do
	line_count=0
	while read line; do
		line_count=$((line_count+1))
		[ $line_count -lt 3 ] && continue
		set -- $line
		if [ $# != 17 ]; then
			echo "data error: # $# != 17" 1>&2
			continue
		fi
		ifname="${1%:}"
		[ "$ifname" = lo ] && continue
		e_ifname="`printf %s \"$ifname\" | sed -r 's/[.-]/_/g'`"
		eval "last_rx=\$last_rx_$e_ifname"
		eval "last_tx=\$last_tx_$e_ifname"
		if [ -n "$last_rx" ] && [ -n "$last_tx" ] && [ $count = $interval ]; then
			rx_diff=$((${2}-last_rx))
			tx_diff=$((${10}-last_tx))
			[ "$rx_diff" -lt 0 ] && rx_diff=0
			[ "$tx_diff" -lt 0 ] && tx_diff=0
			http_post "${INFLUXDB_BASE_URL}write?db=$INFLUXDB_DB_NAME" \
				"traffic,host=$HOSTNAME,interface=$ifname receive_rate=$rx_diff,transmit_rate=$tx_diff"
		fi
		eval "last_rx_$e_ifname=${2}"
		eval "last_tx_$e_ifname=${10}"
	done < /proc/net/dev
	if [ $count = $interval ]; then
		count=0
	else
		count=$((count+1))
	fi
	sleep 1
done
