#!/bin/sh

# Copyright (C) 2014-2022 Daniel Baumann <daniel.baumann@open-infrastructure.net>
#
# SPDX-License-Identifier: GPL-3.0+
#
# 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 <https://www.gnu.org/licenses/>.

set -e

PROJECT="open-infrastructure"
SOFTWARE="compute-tools"
PROGRAM="container"
COMMAND="$(basename ${0})"

CONFIG="/etc/${SOFTWARE}/config"
HOOKS="/etc/${SOFTWARE}/hooks"
MACHINES="/var/lib/machines"
SCRIPTS="/usr/share/${SOFTWARE}/build-scripts"
CONFIG_TEMPLATE="/usr/share/${SOFTWARE}/config/container.conf.in"

Parameters ()
{
	GETOPT_LONGOPTIONS="name:,cnt.auto:,cnt.container-server:,cnt.overlay:,cnt.overlay-options:,cnt.start:,bind:,bind-ro:,capability:,drop-capability:,script:,verbose,"
	GETOPT_OPTIONS="n:,b:,c:,d:,s:,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
				;;

			--cnt.auto)
				CNT_AUTO="${2}"
				shift 2
				;;

			--cnt.container-server)
				CNT_CONTAINER_SERVER="${2}"
				shift 2
				;;

			--cnt.overlay)
				CNT_OVERLAY="${2}"
				shift 2
				;;

			--cnt.overlay-options)
				CNT_OVERLAY_OPTIONS="${2}"
				shift 2
				;;

			--cnt.start)
				CNT_START="${2}"
				shift 2
				;;

			-b|--bind)
				BIND="${2}"
				shift 2
				;;

			--bind-ro)
				BIND_RO="${2}"
				shift 2
				;;

			-c|--capability)
				CAPABILITY="${2}"
				shift 2
				;;

			-d|--drop-capability)
				DROP_CAPABILITY="${2}"
				shift 2
				;;

			-s|--script)
				SCRIPT="${2}"
				shift 2
				;;

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

			--)
				shift 1
				break
				;;

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

Usage ()
{
	echo "Usage: ${PROGRAM} ${COMMAND} -n|--name NAME [--cnt.auto=true|false|force-true|last-on|last-off] [--cnt.container-server=true|false|FQDN] [--cnt.overlay=DIRECTORY_LOWER:DIRECTORY_UPPER:DIRECTORY_WORK:DIRECTORY_MERGED] [--cnt.overlay-options=OPTION[,OPTION]] [--cnt.start=OPTION[,OPTION]] [-b|--bind DIRECTORY:DIRECTORY[:OPTIONS]] [--bind-ro DIRECTORY:DIRECTORY[:OPTIONS]] [-c|--capability CAPABILITY[,CAPABILITY]] [-d|--drop-capability DROP_CAPABILITY[,DROP_CAPABILITY]] [-s|--script SCRIPT] [-v|--verbose] [-- SCRIPT_OPTIONS]" >&2
	echo
	echo "See ${COMMAND}(1), ${PROGRAM}(1) and ${PROJECT}(7) for more information."

	exit 1
}

Parameters "${@}"

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

case "${NAME}" in
	ALL)
		echo "'${NAME}': name 'ALL' is reserved to expand to all available container" >&2
		exit 1
		;;
esac

if [ -e "${CONFIG}/${NAME}.conf" ]
then
	echo "'${NAME}': container already exists or ${CONFIG}/${NAME}.conf has not been removed" >&2
	exit 1
fi

if [ -z "${SCRIPT}" ]
then
	if [ -e "${SCRIPTS}/default" ]
	then
		TARGET="$(basename $(readlink ${SCRIPTS}/default))"

		case "${TARGET}" in
			container_build-script)
				TARGET="$(basename $(readlink /etc/alternatives/container_build-script))"
				;;
		esac

		if [ -e "${SCRIPTS}/${TARGET}" ]
		then
			SCRIPT="${TARGET}"
		else
			echo "default -> '${TARGET}': no such script" >&2
			exit 1
		fi
	else
		SCRIPT="debian"
	fi
else
	if [ ! -e "${SCRIPTS}/${SCRIPT}" ]
	then
		echo "'${SCRIPT}': no such script" >&2
		exit 1
	fi
fi

case "${VERBOSE}" in
	true)

cat << EOF
################################################################################
Building container: ${NAME}
################################################################################
EOF

		;;
esac

CNT_CONTAINER_SERVER="${CNT_CONTAINER_SERVER:-$(hostname -f 2> /dev/null || hostname)}"

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

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

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

		mkdir -p "${DIRECTORY}"
	done
fi

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

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

		mkdir -p "${DIRECTORY}"
	done
fi

# Creating overlay mounts
if [ -n "${CNT_OVERLAY}" ]
then
	CNT_OVERLAYS="$(echo ${CNT_OVERLAY} | sed -e 's|;| |g')"

	for ENTRY in ${CNT_OVERLAYS}
	do
		DIRECTORY_LOWER="$(echo ${ENTRY} | awk -F: '{ print $1 }')"
		DIRECTORY_UPPER="$(echo ${ENTRY} | awk -F: '{ print $2 }')"
		DIRECTORY_WORK="$(echo ${ENTRY} | awk -F: '{ print $3 }')"
		DIRECTORY_MERGED="$(echo ${ENTRY} | awk -F: '{ print $4 }')"

		for DIRECTORY in "${DIRECTORY_LOWER}" "${DIRECTORY_UPPER}" "${DIRECTORY_WORK}" "${DIRECTORY_MERGED}"
		do
			mkdir -p "${DIRECTORY}"
		done
	done
fi

# config
mkdir -p "${CONFIG}"

sed	-e "s|@CNT_AUTO@|${CNT_AUTO}|g" \
	-e "s|@CNT_CONTAINER_SERVER@|${CNT_CONTAINER_SERVER}|g" \
	-e "s|@CNT_NETWORK_BRIDGE@|${CNT_NETWORK_BRIDGE}|g" \
	-e "s|@CNT_OVERLAY@|${CNT_OVERLAY}|g" \
	-e "s|@CNT_OVERLAY_OPTIONS@|${CNT_OVERLAY_OPTIONS}|g" \
	-e "s|@CNT_START@|${CNT_START}|g" \
	-e "s|@NAME@|${NAME}|g" \
	-e "s|@BIND@|${BIND}|g" \
	-e "s|@BIND_RO@|${BIND_RO}|g" \
	-e "s|@BOOT@|yes|g" \
	-e "s|@CAPABILITY@|${CAPABILITY}|g" \
	-e "s|@DIRECTORY@|${MACHINES}/${NAME}|g" \
	-e "s|@DROP_CAPABILITY@|${DROP_CAPABILITY}|g" \
	-e "s|@LINK_JOURNAL@|no|g" \
	-e "s|@MACHINE@|${NAME}|g" \
	-e "s|@NETWORK_VETH_EXTRA@|${NETWORK_VETH_EXTRA}|g" \
	-e "s|@PRIVATE_USERS@|no|g" \
	-e "s|@REGISTER@|yes|g" \
"${CONFIG_TEMPLATE}" > "${CONFIG}/${NAME}.conf"

# Run
"${SCRIPTS}/${SCRIPT}" $(echo "${@}" | sed -e 's| -- | |')

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

# done
echo "'${NAME}': container built."