#!/bin/sh

# container-tools - Manage systemd-nspawn containers
# Copyright (C) 2014-2017 Daniel Baumann <daniel.baumann@open-infrastructure.net>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

set -e

COMMAND="$(basename ${0})"

CONFIG="/etc/container-tools/config"
HOOKS="/etc/container-tools/hooks"
MACHINES="/var/lib/machines"

Parameters ()
{
	GETOPT_LONGOPTIONS="name:,force,verbose,"
	GETOPT_OPTIONS="n:,f,v,"

	PARAMETERS="$(getopt --longoptions ${GETOPT_LONGOPTIONS} --name=${COMMAND} --options ${GETOPT_OPTIONS} --shell sh -- ${@})"

	if [ "${?}" != "0" ]
	then
		echo "'${COMMAND}': getopt exit" >&2
		exit 1
	fi

	eval set -- "${PARAMETERS}"

	while true
	do
		case "${1}" in
			-n|--name)
				NAME="${2}"
				shift 2
				;;

			-f|--force)
				FORCE="true"
				shift 1
				;;

			-f|--verbose)
				VERBOSE="true"
				shift 1
				;;

			--)
				shift 1
				break
				;;

			*)
				echo "'${COMMAND}': getopt error" >&2
				exit 1
				;;
		esac
	done
}

Usage ()
{
	echo "Usage: container ${COMMAND} -n|--name NAME [-f|--force] [-v|--verbose]" >&2
	exit 1
}

Rmdir ()
{
	DIRECTORIES="${@}"

	for DIRECTORY in ${DIRECTORIES}
	do
		PARENT_DIRECTORY="/$(echo ${DIRECTORY} | cut -d / -f 2)"

		if [ "${PARENT_DIRECTORY}" != "${DIRECTORY}" ]
		then
			# the directory is at least two levels down from /
			cd "${PARENT_DIRECTORY}"

			CRUFT="$(echo ${DIRECTORY} | cut -d / -f 3-)"
			rmdir --ignore-fail-on-non-empty --parents "${CRUFT}" > /dev/null 2>&1 || true

			cd "${OLDPWD}"
		fi
	done
}

Parameters "${@}"

if [ -z "${NAME}" ]
then
	Usage
fi

if [ ! -e "${MACHINES}/${NAME}" ] && [ ! -e "${CONFIG}/${NAME}.conf" ]
then
	echo "'${NAME}': no such container" >&2
	exit 1
fi

STATE="$(machinectl show ${NAME} 2>&1 | awk -F= '/^State=/ { print $2 }')"

case "${STATE}" in
	running)
		echo "'${NAME}': container is started" >&2
		exit 1
		;;
esac

case "${FORCE}" in
	true)
		;;

	*)
		echo -n "'${NAME}': remove container '${NAME}' [y|N]? "
		read FORCE

		FORCE="$(echo ${FORCE} | tr [A-Z] [a-z])"

		case "${FORCE}" in
			y|yes)
				;;

			*)
				exit 1
				;;
		esac
		;;
esac

case "${VERBOSE}" in
	true)
		RM_OPTIONS="--verbose"
		;;

	*)
		RM_OPTIONS=""
		;;
esac

# Pre hooks
for FILE in "${HOOKS}/pre-${COMMAND}".* "${HOOKS}/${NAME}.pre-${COMMAND}"
do
	if [ -x "${FILE}" ]
	then
		"${FILE}"
	fi
done

# data
if [ -e "${CONFIG}/${NAME}.conf" ]
then
	# Removing rw bind mounts
	BIND="$(awk -F= '/^bind=/ { print $2 }' ${CONFIG}/${NAME}.conf)"

	if [ -n "${BIND}" ]
	then
		BINDS="$(echo ${BIND} | sed -e 's|;| |g')"

		for BIND in ${BINDS}
		do
			DIRECTORY="$(echo ${BIND} | awk -F: '{ print $1 }')"

			Rmdir "${DIRECTORY}"
		done
	fi

	# Removing ro bind mounts
	BIND_RO="$(awk -F= '/^bind-ro=/ { print $2 }' ${CONFIG}/${NAME}.conf)"

	if [ -n "${BIND_RO}" ]
	then
		BINDS_RO="$(echo ${BIND_RO} | sed -e 's|;| |g')"

		for BIND_RO in ${BINDS_RO}
		do
			DIRECTORY="$(echo ${BIND_RO} | awk -F: '{ print $1 }')"

			Rmdir "${DIRECTORY}"
		done
	fi
fi

# Run
rm --preserve-root --one-file-system -rf ${RM_OPTIONS} "${MACHINES}/${NAME}"
rm -f ${RM_OPTIONS} "${CONFIG}/${NAME}.conf"

# Post hooks
for FILE in "${HOOKS}/post-${COMMAND}".* "${HOOKS}/${NAME}.post-${COMMAND}"
do
	if [ -x "${FILE}" ]
	then
		"${FILE}"
	fi
done