#!/bin/bash
# Copyright (c) 2000-2020 Synology Inc. All rights reserved.

BIN_SYNOSYSTEMCTL="/usr/syno/bin/synosystemctl"
SERVICE_NAME="sssd"

sssd_db_cache_path="/var/lib/sss/db"
sssd_vol_cache_folder="@sssd_cache"
sssd_force_use_root_partition="/tmp/sssd_cache_force_use_root_partition"
SUPPORT_SOFS=`/usr/syno/bin/synogetkeyvalue /etc/synoinfo.conf support_hyper_converged`

logger_err()
{
	logger -s -p user.warn -t "sssd.sh" "$@"
}

create_dir() {
	mkdir -p "${1}"
	chmod 700 "${1}"
}

get_first_volume() {
	if [ -f "${sssd_force_use_root_partition}" ] || [ "yes" = "$SUPPORT_SOFS" ]; then
		echo "${sssd_db_cache_path}"
		return
	fi

	local vol_path
	vol_path="$(/usr/syno/bin/servicetool --get-available-volume)"
	if [ "$?" == "0" ]; then
		vol_path="${sssd_db_cache_path}"
	fi
	echo ${vol_path}
}

get_sssd_vol_path() {
	if [ ! -e ${sssd_db_cache_path} ]; then
		return
	fi

	local -r cache_path="$(/bin/realpath ${sssd_db_cache_path})"
	local -r vol_name="$(echo "${cache_path}" | awk -F'/' '{print $2}')"
	echo "/${vol_name}"
}

is_systemd_service_enabled() {
	local -r is_enable=$(/usr/syno/bin/synosystemctl get-enable-status "${1}")

	if [ "${is_enable}" == "enabled" ]; then
		return 0
	fi
	return 1
}

is_vol_avail_size_enough () {
	local -r vol_avail_size="$(df -BM "${1}" | tail -1 | awk '{print $4}' | awk -F'M' '{print $1}')"
	if [ "${vol_avail_size}" -ge "10" ]; then
		return 0
	fi
	return 1
}

is_sssd_vol_cache_path_valid() {
	local -r vol_path="$(get_sssd_vol_path)"

	if [[ -z "${vol_path}" ]]; then
		return 1
	fi

	# check volume path valid
	if [ ! -e "${vol_path}" ] || [ "x${vol_path:0:7}" != "x/volume" ] \
		|| ! /bin/grep -q "${vol_path}" "/proc/mounts"; then
		return 1
	fi

	# check volume size is enough
	if is_vol_avail_size_enough "${vol_path}"; then
		return 0
	fi
	return 1
}

sssd_cache_path_setup() {
	/bin/rm -rf ${sssd_db_cache_path}

	local vol_path
	if [ -e "${1}" ]; then ## hook script will source this file and use this function
		vol_path="${1}"
	else
		vol_path="$(get_first_volume)"
	fi

	if [ "x${vol_path}" == "x${sssd_db_cache_path}" ]; then
		logger_err "Can't find valid volume for db cache, use root partition."
		create_dir "${sssd_db_cache_path}"
	else
		logger_err "Found valid volume for db cache. [${vol_path}]"
		local -r sssd_vol_cache_path="${vol_path}/${sssd_vol_cache_folder}"
		rm -rf "${sssd_vol_cache_path}"
		create_dir "${sssd_vol_cache_path}"
		ln -s "${sssd_vol_cache_path}" ${sssd_db_cache_path}
	fi
}

sss_volume_dependency() {
	local -r action=${1}
	local -r vol_path="$(get_sssd_vol_path)"
	if [ "x${vol_path:0:7}" = "x/volume" ]; then
		${BIN_SYNOSYSTEMCTL} ${action} ${SERVICE_NAME} ${vol_path}
	fi
}

sss_prestart_sssd() {
	/bin/chmod 644 "/etc/sssd/sssd.conf"
	/bin/find "/etc/sssd/conf.d" -type f -exec /usr/bin/chmod 644 {} \;

	# Drop cache when booting up
	if /usr/syno/bin/synobootseq --is-booting-up > /dev/null 2>&1 ; then
		/bin/rm -rf "${sssd_db_cache_path}"
	fi

	if ! is_sssd_vol_cache_path_valid ; then
		sssd_cache_path_setup
	fi

	sss_volume_dependency "register-volume"
}

sss_poststart_sssd() {
	/bin/rm -f "${sssd_force_use_root_partition}"
}

sss_poststop_sssd() {
	# If db cache in root partition, it should be clear when sssd stop.
	if is_sssd_vol_cache_path_valid ; then
		sss_volume_dependency "unregister-volume"
		return
	fi
	/bin/rm -rf ${sssd_db_cache_path}
}

if [ "${BASH_SOURCE[0]}" == "${0}" ]; then
	if [ $# -eq 0 ]; then
		exit 1
	else
		action="$1"; shift
	fi

	case ${action} in
		prestart)
			sss_prestart_sssd
			;;
		poststart)
			sss_poststart_sssd
			;;
		poststop)
			sss_poststop_sssd
			;;
		*)
			echo "Wrong argument"
			exit 1
			;;
	esac
fi
# vim: noet: ts=4: sw=4: