#!/bin/sh

#
# check_updates.sh
# $1 - message transport agent, either sendmail or gotify, default to sendmail
#

PATH="$PATH:/usr/sbin:/sbin"

TMP_FILE=$(mktemp)
MESSAGE=$(mktemp)
MESSAGE_IS_MAIL=1

# message transport agent, either sendmail or gotify
# if you use gotify, you need to install gotify-cli
MTA=${1:-sendmail}
case "${MTA}" in
	sendmail)
		MTA='sendmail -t root@$(hostname -f)'
		;;
	gotify)
		MTA='gotify p -q -t $TITLE'
		MESSAGE_IS_MAIL=0
		;;
	*)
		echo "Error: unknown MTA"
		exit 1
		;;
esac

# Possible race condition: if someone runs `eix blah` at the exact same time,
# it will block the update. But that seems highly improbable.
# The mail goal is to avoid stacking updates or eix-sync/eix-updates
PORTAGE_RUNING=$(pgrep 'emerge|eix')
if [ "${PORTAGE_RUNING}" ]; then
       echo "Error: another emerge is already running, exiting"
       exit 1
fi

PORTAGE_QUIET='1'

eix-sync 1>/dev/null 2>${TMP_FILE} || eix-update 1>/dev/null 2>${TMP_FILE}

emerge -v --update --newuse --deep --with-bdeps=y --quiet-build=y @security \
	&>> ${TMP_FILE}
emerge -v --update --newuse --deep --with-bdeps=y --quiet-build=y @system \
	&>> ${TMP_FILE}
emerge -v --update --newuse --deep --with-bdeps=y --quiet-build=y @unavailable
	&>> ${TMP_FILE}
emerge -v --update --newuse --deep --with-bdeps=y --quiet-build=y @world \
	&>> ${TMP_FILE}

if [ "$(grep '\[ebuild     U' ${TMP_FILE})" != '' ]; then
	if [ ${MESSAGE_IS_MAIL} -eq 1 ]; then
		# The message is a mail we add corresponding headers
		echo "From: $(whoami)@$(hostname -f)" > ${MESSAGE}
		echo "To: root@$(hostname -f)" >> ${MESSAGE}
		echo "Subject: $(hostname -f):$(grep Total: ${TMP_FILE} \
			| cut -d ':' -f 2 | cut -d ')' -f 1))" >> ${MESSAGE}
		echo "Content-Type: text/plain; charset=UTF-8" >> ${MESSAGE}
		echo "Date: $(date --rfc-email)" >> ${MESSAGE}
		printf "\n" >> ${MESSAGE}
	else 
		TITLE = "$(hostname -f):$(grep Total: ${TMP_FILE} \
			| cut -d ':' -f 2 | cut -d ')' -f 1)"
	fi
	
	cat ${TMP_FILE} >> ${MESSAGE}

	if [ "$(lsof -n | awk '{ if ($6 == "DEL") print $9 }' | sort -u)" ]; then
		restart-services --no-color >> ${MESSAGE}
	fi

	if ! [ -z "$(grep -v '{}' /var/lib/portage/preserved_libs_registry)" ]; then
		emerge -v --quiet-build=y @preserved-rebuild >> ${MESSAGE}
	fi

	emerge -p --depclean --with-bdeps\=y >> ${MESSAGE}

	eix-test-obsolete \
		| grep -Pv '^No|^Skipping|[Aa]ll.*packages are in the database' \
		>> ${MESSAGE}

	eval "${MTA}" < "${MESSAGE}"
fi

rm ${TMP_FILE} ${MESSAGE}