#!/bin/sh
#
# Copyright (c) 2024 Mischa Peters <mischa @ openbsd.amsterdam>
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notice and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
# WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
# MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
# ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
# WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
# ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
# OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#
LOAD=90
TTL=10
GRACE=6

usage() {
	echo "usage: ${0##*/} [-l load (90)] [-t ttl (10)] [-g grace (6)] [-d]" 1>&2
	exit
}

while getopts l:t:g:dh arg; do
	case ${arg} in
	l)	LOAD=${OPTARG};;
	t)	TTL=${OPTARG};;
	g)	GRACE=${OPTARG};;
	d)	DEBUG=1;;
	h)	usage;;
	*)	usage;;
	esac
done

HOSTNAME=$(hostname)
TIMESTAMP=$(date +%s)
OUT=$(ps -uU _vmd | awk -v var="${LOAD}" '$12 !~ /\// && $3 > var {print $12}')
if [ -z "${OUT}" ]; then
	if [ -n "${DEBUG}" ]; then echo "No VM over the threshold overload"; fi
	rm -rf /tmp/vm*
	exit 0;
fi

for VM in ${OUT}; do
	if [ -n "${DEBUG}" ]; then echo -n "${VM}"; fi
	if [ ! -f /home/mischa/vms/${VM}.exclude ]; then
		if [ -f /tmp/${VM} ]; then
			FIRSTSEEN=$(awk 'NR==1' /tmp/${VM})
			LASTSEEN=$(awk 'NR==2' /tmp/${VM})

			if [ -n "${DEBUG}" ]; then
				echo -n " - ${FIRSTSEEN}"
				echo -n ", $((${TIMESTAMP} - ${FIRSTSEEN}))"
				echo -n ", ${LASTSEEN}"
				echo ", $((${TIMESTAMP} - ${LASTSEEN}))"
			fi

			if [[ $(( ${TIMESTAMP} - ${LASTSEEN} )) -gt $(( 60 * ${TTL} )) ]]; then
				echo ${FIRSTSEEN} > /tmp/${VM}
				echo ${TIMESTAMP} >> /tmp/${VM}
			fi
			if [[ $(( ${TIMESTAMP} - ${FIRSTSEEN} )) -gt $(( 60 * 60 * ${GRACE} )) ]]; then
				if [[ $(( ${TIMESTAMP} - ${LASTSEEN} )) -gt $(( 60 * ${TTL} )) ]]; then
					/home/mischa/bin/notify.pl cpu ${VM}
					echo "${VM} over ${LOAD}% CPU load for ${GRACE} hours" | mail -s "${HOSTNAME} - ${VM} over ${LOAD}% CPU load for ${GRACE} hours" -r root@obsda.ms cpu@obsda.ms
					rm -rf /tmp/${VM}
				fi
			fi
		else
			if [ -n "${DEBUG}" ]; then echo " - firstseen"; fi
			echo ${TIMESTAMP} > /tmp/${VM}
			echo ${TIMESTAMP} >> /tmp/${VM}
		fi
	fi
done

if ls /tmp/vm* 1> /dev/null 2>&1; then
	SEEN=$(ls -1 /tmp/vm* | awk -F'/' '{print $3}')
	for s in ${SEEN[@]}; do
		if [[ "${OUT[*]}" != *"${s}"* ]]; then
			if [ -n "${DEBUG}" ]; then echo "${s} - remove from tracking list"; fi
			rm -rf /tmp/${s}
		fi
	done
fi