#!/bin/sh

# Copyright (C) 2014-2021 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 <http://www.gnu.org/licenses/>.

set -e

PROJECT="open-infrastructure"
SOFTWARE="compute-tools"
PROGRAM="container"
SCRIPT="${0}"

HOOKS="/etc/${PROJECT}/${PROGRAM}/hooks"
KEYS="/etc/${PROJECT}/${PROGRAM}/keys"
MACHINES="/var/lib/machines"
CACHE="/var/cache/${PROJECT}/${PROGRAM}/system"

Parameters ()
{
	GETOPT_LONGOPTIONS="bind:,bind-ro:,script:,name:,architecture:,clean,password:,server:,setup:,system:,"
	GETOPT_OPTIONS="b:,s:,n:,a:,p:"

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

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

	eval set -- "${PARAMETERS}"

	while true
	do
		case "${1}" in
			-b|--bind)
				# ignore
				shift 2
				;;

			--bind-ro)
				# ignore
				shift 2
				;;

			--cnt.auto)
				# ignore
				shift 2
				;;

			--cnt.container-server)
				# ignore
				shift 2
				;;

			-s|--script)
				# ignore
				shift 2
				;;

			-n|--name)
				NAME="${2}"
				shift 2
				;;

			-a|--architecture)
				ARCHITECTURE="${2}"
				shift 2
				;;

			--clean)
				CLEAN="true"
				shift 1
				;;

			-p|--password)
				PASSWORD="${2}"
				shift 2
				;;

			--server)
				SERVER="${2}"
				shift 2
				;;

			--setup)
				SETUP="${2}"
				shift 2
				;;

			--system)
				SYSTEM="${2}"
				shift 2
				;;

			--)
				shift 1
				break
				;;

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

Usage ()
{
	echo "Usage: container create -n|--name NAME -s|--script ${SCRIPT} -- [--clean] [-p|--password PASSWORD] [--server SERVER] [--setup SETUP] [--system SYSTEM]" >&2
	exit 1
}

Parameters "${@}"

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

if [ -e "${MACHINES}/${NAME}" ]
then
	echo "'${NAME}': container already exists" >&2
	exit 1
fi

if [ ! -x /usr/bin/curl ]
then
	echo "'${NAME}': /usr/bin/curl - no such file." >&2
	exit 1
fi

if [ "$(id -u)" -ne 0 ]
then
	echo "'${NAME}': need root privileges" >&2
	exit 1
fi

COMPRESSIONS=""

if [ -x /usr/bin/lzip ]
then
	COMPRESSIONS="${COMPRESSIONS} lz"
fi

if [ -x /usr/bin/xz ]
then
	COMPRESSIONS="${COMPRESSIONS} xz"
fi

if [ -x /bin/gzip ]
then
	COMPRESSIONS="${COMPRESSIONS} gz"
fi

if [ -z "${COMPRESSIONS}" ]
then
	echo "'${NAME}': no supported compressor available (lz, xz, gz)."
	exit 1
fi

SERVER="${SERVER:-https://get.open-infrastructure.net/system/container/debian}"
PASSWORD="${PASSWORD:-$(dd if=/dev/urandom bs=12 count=1 2> /dev/null | base64)}"

VERSION="$(container version)"

export SERVER

Debconf ()
{
	# Configure local debconf
	mkdir -p "${DEBCONF_TMPDIR}/debconf"

cat > "${DEBCONF_TMPDIR}/debconf.systemrc" << EOF
Config: configdb
Templates: templatedb

Name: config
Driver: File
Mode: 644
Reject-Type: password
Filename: ${DEBCONF_TMPDIR}/debconf/config.dat

Name: passwords
Driver: File
Mode: 600
Backup: false
Required: false
Accept-Type: password
Filename: ${DEBCONF_TMPDIR}/debconf/passwords.dat

Name: configdb
Driver: Stack
Stack: config, passwords

Name: templatedb
Driver: File
Mode: 644
Filename: ${DEBCONF_TMPDIR}/debconf/templates.dat
EOF

	DEBCONF_SYSTEMRC="${DEBCONF_TMPDIR}/debconf.systemrc"
	export DEBCONF_SYSTEMRC
}

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

# Run

# FIXME: default server via configuration file

CURL_OPTIONS=""

if curl -V | grep -qs http2
then
	CURL_OPTIONS="${CURL_OPTIONS} --http2"
fi

if [ -z "${SYSTEM}" ]
then
	# Downloading container list
	if curl --fail --head --output /dev/null --silent "${SERVER}/container-list.txt"
	then
		mkdir -p "/tmp/${SOFTWARE}"
		DEBCONF_TMPDIR="$(mktemp -d -p "/tmp/${SOFTWARE}" -t $(basename ${0}).XXXX)"
		export DEBCONF_TMPDIR

		if [ -z "${ARCHITECTURE}" ]
		then
			case "$(dpkg --print-architecture)" in
				amd64)
					GREP_PATTERN="(amd64|i386)"
					;;
			esac
		fi

		GREP_PATTERN="${GREP_PATTERN:-${ARCHITECTURE}}"

		echo "Downloading $(echo ${SERVER} | awk -F/ '{ print $3 }') container list"
		curl	--fail --location --progress-bar --user-agent ${SOFTWARE}/${VERSION} ${CURL_OPTIONS} \
			"${SERVER}/container-list.txt" | grep -E "${GREP_PATTERN}" > "${DEBCONF_TMPDIR}/container-list.txt"

		umask 0022

		Debconf

		# Run debconf parts
		for DEBCONF_SCRIPT in /usr/share/${PROJECT}/${PROGRAM}/scripts/curl.d/*
		do
			if [ -x "${DEBCONF_SCRIPT}" ]
			then
				"${DEBCONF_SCRIPT}"
			fi
		done

		# Read-in configuration from debconf
		. "${DEBCONF_TMPDIR}/debconf.default"

		# Remove debconf temporary files
		rm --preserve-root --one-file-system -rf "${DEBCONF_TMPDIR}"
		rmdir --ignore-fail-on-non-empty "/tmp/${SOFTWARE}" 2>&1 || true
	fi
fi

for COMPRESSION in ${COMPRESSIONS}
do
	if curl --fail --head --output /dev/null --silent "${SERVER}/${SYSTEM}.${COMPRESSION}"
	then
		SYSTEM="${SYSTEM}.${COMPRESSION}"
		break
	fi
done

# Downloading container files
mkdir -p "${CACHE}"

SETUP="${SETUP:-$(echo ${SYSTEM} | sed -e 's|.system.tar.|.setup.tar.|')}"

for FILE in	"${SYSTEM}" "${SYSTEM}.sign" "${SYSTEM}.sha512" \
		"${SETUP}" "${SETUP}.sign" "${SETUP}.sha512"
do
	if curl --fail --head --output /dev/null --silent "${SERVER}/${FILE}"
	then
		case "${FILE}" in
			*.sha512)
				if [ -e "${CACHE}/$(basename ${FILE} .sha512).sign" ]
				then
					continue
				fi
				;;
		esac

		if [ -e "${CACHE}/${FILE}" ]
		then
			CURL_TIME_COND="--time-cond ${CACHE}/${FILE}"
		else
			CURL_TIME_COND=""
		fi

		echo "Downloading ${FILE}"
		curl	--fail --location --progress-bar --user-agent ${SOFTWARE}/${VERSION} ${CURL_OPTIONS} ${CURL_TIME_COND} \
			"${SERVER}/${FILE}" -o "${CACHE}/${FILE}"
	fi
done

cd "${CACHE}"

for FILE in "${SYSTEM}" "${SETUP}"
do
	if [ ! -e "${FILE}" ]
	then
		continue
	fi

	if [ -e "${FILE}.sign" ]
	then
		echo -n "Verifying ${FILE}:"

		set +e
		gpg --homedir "${KEYS}" --verify "${FILE}.sign" "${FILE}" > /dev/null 2>&1
		GNUPG="${?}"
		set -e

		case "${GNUPG}" in
			0)
				echo " gpg ok."
				continue
				;;

			*)
				echo " gpg failed."
				exit 1
				;;
		esac
	elif [ -e "${FILE}.sha512" ]
	then
		echo -n "Verifying ${FILE}:"

		set +e
		sha512sum --check "${FILE}.sha512" --status
		SHA512SUM="${?}"
		set -e

		case "${SHA512SUM}" in
			0)
				echo " sha512 ok."
				;;

			*)
				echo " sha512 failed."
				exit 1
				;;
		esac
	fi
done

cd "${OLDPWD}"

case "${SYSTEM}" in
	*.gz)
		TAR_OPTIONS="--gzip"

		if [ ! -e /bin/gzip ]
		then
			echo -en "\n"
			echo "'${NAME}': /bin/lzip - no such file." >&2
			exit 1
		fi
		;;

	*.lz)
		TAR_OPTIONS="--lzip"

		if [ ! -e /usr/bin/lzip ]
		then
			echo -en "\n"
			echo "'${NAME}': /usr/bin/lzip - no such file." >&2
			exit 1
		fi
		;;

	*.xz)
		TAR_OPTIONS="--xz"

		if [ ! -e /usr/bin/xz ]
		then
			echo -en "\n"
			echo "'${NAME}': /usr/bin/xz - no such file." >&2
			exit 1
		fi
		;;

	*)
		TAR_OPTIONS=""
		;;
esac

for FILE in "${SYSTEM}" "${SETUP}"
do
	if [ ! -e "${CACHE}/${FILE}" ]
	then
		continue
	fi

	case "${FILE}" in
		*.system.tar.*)
			DIRECTORY="${MACHINES}/${NAME}"
			;;

		*.setup.tar.*)
			DIRECTORY="${MACHINES}/${NAME}/setup"
			;;
	esac

	mkdir -p "${DIRECTORY}"

	if [ -e /usr/bin/pv ]
	then
		echo "Unpacking ${FILE}"
		pv --format '%p' --width 77 "${CACHE}/${FILE}" | tar xf - ${TAR_OPTIONS} -C "${DIRECTORY}" --strip 1
	else
		echo -n "Unpacking ${FILE}:"
		tar xf "${CACHE}/${FILE}" ${TAR_OPTIONS} -C "${DIRECTORY}" --strip 1
		echo " ok."
	fi
done

if [ -x "${MACHINES}/${NAME}/setup/container" ]
then
	chroot "${MACHINES}/${NAME}" /usr/bin/env -i \
		LC_ALL="C" PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/local/games:/usr/games" TERM="${TERM}" \
		DEBIAN_FRONTEND="dialog" DEBIAN_PRIORITY="low" \
		DEBCONF_NONINTERACTIVE_SEEN="true" DEBCONF_NOWARNINGS="true" \
		NAME="${NAME}" \
		/setup/container

	rm -rf "${MACHINES}/${NAME}/setup"
fi

# Creating machine-id
chroot "${MACHINES}/${NAME}" systemd-machine-id-setup > /dev/null 2>&1

# Setting hostname
echo "${NAME}" > "${MACHINES}/${NAME}/etc/hostname"

# Copying resolv.conf
cp -L /etc/resolv.conf "${MACHINES}/${NAME}/etc/resolv.conf"

# Setting root password
echo root:${PASSWORD} | chroot "${MACHINES}/${NAME}" chpasswd
echo "${NAME}: root password set to '${PASSWORD}'."

# Remove cache
case "${CLEAN}" in
	true)
		rm -f "${CACHE}/${SYSTEM}" "${CACHE}/${SYSTEM}.sha512"
		rm -f "${CACHE}/${SETUP}" "${CACHE}/${SETUP}.sha512"
		;;
esac

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