#!/bin/sh

_PGDATA=/var/services/pgsql
PGDATA="`/usr/bin/readlink ${_PGDATA}`"
PGDIRNAME="`/usr/bin/dirname ${PGDATA}`"
PGDATA32="${PGDIRNAME}/pgsql.32bit.`/bin/date +%s`"
PGDATA64="${PGDIRNAME}/pgsql.64bit.`/bin/date +%s`"
PGMAJORVERSION=9.3
UsbStation=`/bin/get_key_value /etc.defaults/synoinfo.conf usbstation`
UnixPerm="no"
PGPIDFILE="/var/run/postgresql/postmaster.pid"
PGUPGRADE_FLAG="/tmp/.UpgradePGSQLDatabase"
ERR_MESSAGE="Failed to upgrade PostgreSQL, please contact Synology for support."
ret=0
BOOL_INIT_DB=false

EchoDate()
{
	echo "[`/bin/date '+%Y-%m-%d %H:%M:%S %Z'`]: $1"
}

ChkPGSQLShare()
{
	/usr/syno/bin/servicetool --get-service-path pgsql >/dev/null 2>&1
	if [ $? -eq 0 ]; then
		EchoDate "No volume to start PostgreSQL."
		return 1
	fi
	return 0
}

ChkExecEnv()
{
	if ! ChkPGSQLShare; then
		exit 1
	fi

	if [ ! -f /etc/postgresql/postgresql.conf ]; then
		/bin/cp -a /etc.defaults/postgresql /etc
	fi

	/bin/mkdir -p /run/postgresql
	/bin/chown -R postgres: /etc/postgresql /run/postgresql
	/bin/chmod 700 /etc/postgresql
	if [ "yes" = "${UsbStation}" ]; then
		/bin/cp -f /etc/postgresql/postgresql.conf ${PGDATA}/postgresql.conf

		PgsqlVolume=`/usr/syno/bin/servicetool --get-service-volume pgsql`
		VolFsType=`/usr/syno/bin/synofstool --get-fs-type ${PgsqlVolume}`
		if [ "ext3" = "${VolFsType}" -o "ext4" = "${VolFsType}" -o "hfsplus" = "${VolFsType}" ]; then
			UnixPerm="yes"

			/bin/chown -R postgres: ${PGDATA}
			/bin/chmod 700 ${PGDATA}
			/usr/bin/find ${PGDATA}/ -type d ! -perm 700 -exec chmod 700 {} \;
			/usr/bin/find ${PGDATA}/ -type f ! -perm 600 -exec chmod 600 {} \;
		fi
	else
		/bin/chown -R postgres: ${PGDATA}
		/bin/chmod 700 ${PGDATA}
		/usr/bin/find ${PGDATA}/ -type d ! -perm 700 -exec chmod 700 {} \;
		/usr/bin/find ${PGDATA}/ -type f ! -perm 600 -exec chmod 600 {} \;

		if [ ! -L ${PGDATA}/postgresql.conf ]; then
			/bin/ln -sf /etc/postgresql/postgresql.conf ${PGDATA}/postgresql.conf
		fi
	fi
}

TuneParams()
{
	declare -A params
	local shared_buffers config

	##### Get total memory size in system
	local mem=$(grep MemTotal /proc/meminfo | sed -E 's/^MemTotal:\s*([0-9]+)\s*kB$/\1/g')
	local re='^[0-9]+$'

	if ! [[ $mem =~ $re ]]; then
		EchoDate "Memory size is not a number: $mem"
		return 1
	fi

	##### Decide parameter values

	# shared_buffers
	shared_buffers=$(($mem / 8))
	shared_buffers=$(($shared_buffers > 524288 ? 524288 : $shared_buffers)) # max 512MB
	shared_buffers=$(($shared_buffers < 24576  ? 24576  : $shared_buffers)) # min 24MB
	params[shared_buffers]="${shared_buffers}kB"

	# effective_cache_size
	params[effective_cache_size]="$(($mem / 2))kB"

	# timezone
	for i in $(seq 1 3); do
		params[TimeZone]="$(synodate --getNameInTZDB)"
		if [[ "$?" -ne "0" ]]; then
			sleep 1
			unset params[TimeZone]
		else
			break
		fi
	done

	##### Replace parameter values
	config="$(readlink -f "${PGDATA}/postgresql.conf")"
	for key in "${!params[@]}"; do
		EchoDate "Replacing parameter: $key = ${params[$key]}"
		sed -i -E "s|${key}\s*=.*|${key} = ${params[$key]}|g" "$config"
	done
}

ChkCompat()
{
	/usr/bin/pg_controldata --check-compatibility ${PGDATA} 2>/dev/null
	if [ $? -ne 0 ]; then
		EchoDate "Compatibility check is failed. Please check /var/log/postgresql.log for further information."
		/bin/mv -f ${PGDATA} "${PGDIRNAME}/.pgsql.`/bin/date +%s`"
		InitDB
	fi
}

CleanPID()
{
	if [ -f ${PGDATA}/postmaster.pid ]; then
		EchoDate "Find postmaster.pid file"
		EchoDate "-------start postmaster.pid-----"
		/bin/cat ${PGDATA}/postmaster.pid
		EchoDate "-------end postmaster.pid-------"
		/bin/rm -f ${PGDATA}/postmaster.pid
	fi
}

InitDB()
{
	local enable_checksum=""
	local no_fsync=""

	if [ "x`/bin/get_key_value /etc.defaults/synoinfo.conf support_postgresql_data_checksums`" == "xyes" ]; then
		enable_checksum="--data-checksums"
	fi

	if [ ! -d ${PGDATA}/base ]; then
		EchoDate "Initialize PostgreSQL database"

		/bin/mkdir -p ${PGDATA}
		if [ "yes" = "${UsbStation}" ]; then
			/bin/tar zxf /usr/share/postgresql//pgsql.tgz -C ${PGDATA}
			/bin/cp -f /etc/postgresql/postgresql.conf ${PGDATA}/postgresql.conf

			if [ "yes" = "${UnixPerm}" ]; then
				/bin/chown -R postgres: ${PGDATA}
				/bin/chmod 700 /etc/postgresql ${PGDATA}
				/bin/chmod 777 ${PGDATA}/postgresql.conf
			fi
		else
			if [ "x`/usr/syno/bin/synofstool --get-fs-type ${PGDATA}`" == "xbtrfs" ]; then
				EchoDate "${PGDATA} is btrfs"
				no_fsync="--nosync"
			fi

			/bin/chown -R postgres: ${PGDATA}
			/bin/chmod 700 /etc/postgresql ${PGDATA}
			/bin/su postgres -c "/usr/bin/initdb --locale=POSIX --pgdata=${PGDATA} ${enable_checksum} ${no_fsync}" >/dev/null 2>&1
			/bin/ln -sf /etc/postgresql/postgresql.conf ${PGDATA}/postgresql.conf
		fi
		/bin/sync; /bin/sync; /bin/sync

		touch ${PGINIT_FLAG}
		BOOL_INIT_DB=true
	fi
}

ChkNeedDump()
{
	if [ -f /var/.UpgradeBootup -a -f /usr/bin/pg_controldata32 ]; then
		/usr/bin/pg_controldata --check-compatibility ${PGDATA} 2>/dev/null
		if [ $? -ne 0 ]; then
			/usr/bin/pg_controldata32 --check-compatibility ${PGDATA} 2>/dev/null
			if [ $? -eq 0 ]; then
				return 0;
			fi
		fi
	fi
	return 1
}

DumpDB()
{
	if [ -f ${PGDATA}/pgsql-32bit.sql ]; then
		return 0;
	fi
	CleanPID
	start pgsql32
	sec=1
	while [ ${sec} -le 600 ]
	do
		if pidof postgres32; then
			/bin/su postgres -c "/usr/bin/pg_isready" > /dev/null 2>&1
			ret=$?
			# pg_isready retern value: PQPING_OK (1), PQPING_REJECT (2), PQPING_NO_RESPONSE(3), PQPING_NO_ATTEMPT(4)
			if [ ${sec} -ge 180 -a ${ret} -ge 2 ]; then
				/usr/bin/logger -p user.err $ERR_MESSAGE
				stop pgsql32
				return 1
			fi
			if [ ${ret} -eq 0 ]; then
				EchoDate "postgres32 is ready after waiting ${sec} seconds..."
				break
			fi
		elif [ ${sec} -ge 30 ]; then
			EchoDate "postgres32 process start up failed."
			/usr/bin/logger -p user.err $ERR_MESSAGE
			stop pgsql32
			return 1
			break
		fi
		sec=`expr ${sec} + 1`
		sleep 1
	done
	EchoDate "dump postgres32 database."
	/bin/su postgres -c "/usr/bin/pg_dumpall --disable-triggers -f ${PGDATA}/pgsql-32bit.sql > ${PGDATA}/pg_upgrade_dump.log 2>&1"
	if [ $? -ne 0 ]; then
		EchoDate "dump postgres32 database failed."
		/usr/bin/logger -p user.err $ERR_MESSAGE
		return 1
	fi
	stop pgsql32
	return 0
}

UpdatePGSQLWorker()
{
	local i=""
	local pkg=""

	for i in /var/packages/*/conf/resource; do
		[ -f "$i" ] || continue
		if [ "$(jq '.["pgsql-db"]' "$i")" != "null" ]; then
			pkg=`basename "$(dirname "$(dirname "$i")")"`
			echo "Update ${pkg} pgsql-db worker."
			synopkghelper update "$pkg" pgsql-db
			echo "Done updating ${pkg} pgsql-db worker."
		fi
	done
}

case $1 in
	start)
		EchoDate "Start PostgreSQL"
		ChkExecEnv
		TuneParams
		if ChkNeedDump; then
			# need upgrade database
			echo start > $PGUPGRADE_FLAG
			if ! DumpDB; then
				rm $PGUPGRADE_FLAG
			fi
			/bin/mv ${PGDATA} ${PGDATA32}
			InitDB
		fi
		ChkCompat
		CleanPID
		start pgsql

		sec=1
		while [ ${sec} -le 1800 ]
		do
			PG_PID=`status pgsql | awk '{ print $4 }'`
			if [ ! -z "${PG_PID}" ]; then
				/bin/su postgres -c "/usr/bin/pg_isready" > /dev/null 2>&1
				ret=$?
				# pg_isready retern value: PQPING_OK (1), PQPING_REJECT (2), PQPING_NO_RESPONSE(3), PQPING_NO_ATTEMPT(4)
				if [ ${sec} -ge 180 -a ${ret} -ge 2 ]; then
					EchoDate "pg_isready remain 'no response' for 180 seconds.."
					break
				fi
				if [ ${ret} -eq 0 ]; then
					EchoDate "pgsql is ready after waiting ${sec} seconds..."
					break
				fi
			else
				# Error handling
				if /usr/bin/tail -n 6 /var/log/postgresql.log /var/log/upstart/pgsql.log | /bin/grep "could not load pg_hba.conf"; then
					EchoDate "pg_hba.conf is recovered"
					/bin/cp /etc.defaults/postgresql/pg_hba.conf /etc/postgresql/pg_hba.conf
					start pgsql
				elif tail -n 6 /var/log/postgresql.log /var/log/upstart/pgsql.log | grep -E 'configuration file .* contains errors' > /dev/null; then
					rm -f ${PGDATA}/postgresql.conf
					rm -f /etc/postgresql/postgresql.conf
					ChkExecEnv
					EchoDate "postgresql.conf is recovered"
					start pgsql
				elif /usr/bin/tail -n 6 /var/log/postgresql.log /var/log/upstart/pgsql.log | /bin/grep "USE_FLOAT8_BYVAL"; then
					stop pgsql
					EchoDate "USE_FLOAT8_BYVAL incompatable due to migrate."
					if [ -f /usr/bin/pg_controldata32 ]; then
						echo start > $PGUPGRADE_FLAG
						if ! DumpDB; then
							rm $PGUPGRADE_FLAG
						fi
						/bin/mv -f ${PGDATA} ${PGDATA32}
						InitDB
					else
						/bin/mv -f ${PGDATA} ${PGDATA64}
						InitDB
					fi
					start pgsql
				else
					EchoDate "postgrest process start up failed."
					break
				fi
			fi
			sec=`expr ${sec} + 1`
			sleep 1
		done

		if [ ${ret} -ne 0 ]; then
			EchoDate "Failed to start PostgreSQL. Please check /var/log/postgresql.log"
			if /bin/tail /var/log/upstart/pgsql.log -n 6 | /bin/grep "No space left on device"; then
				/usr/syno/bin/synodsmnotify @administrators dsmnotify:system_event widget:pgsql_startup_failed
				/usr/bin/logger -p user.err -t `basename $0` "no space left on device for starting PostgreSQL."
			fi
			exit 1
		else
			if [ -f ${PGUPGRADE_FLAG} -a -f ${PGDATA32}/pgsql-32bit.sql ]; then
				EchoDate "Start restore pgsql data"
				/bin/su postgres -c "/usr/bin/psql < ${PGDATA32}/pgsql-32bit.sql > ${PGDATA32}/pg_upgrade_restore.log 2>&1"
				if [ "`cat $PGUPGRADE_FLAG`" = "timeout" ]; then
					/usr/bin/logger -p user.err -t `basename $0` "pgsql upgrade has been done but exceed 600 second."
					/usr/syno/bin/synodsmnotify @administrators dsmnotify:system_event widget:pgsql_upgrade_done
				fi
				rm $PGUPGRADE_FLAG
				EchoDate "Upgrade pgsql data is done."
			fi
		fi

		/usr/syno/bin/mediaserver.sh start

		if $BOOL_INIT_DB; then
			UpdatePGSQLWorker
		fi
		;;

	stop)
		stop pgsql
		;;

	restart)
		ChkExecEnv
		ChkCompat
		TuneParams
		stop pgsql
		start pgsql
		;;

	reload)
		TuneParams
		/bin/su postgres -c "/usr/bin/pg_ctl -s -D ${_PGDATA} reload" || exit 1
		;;

	status)
		if ! ChkPGSQLShare; then
			exit 1
		fi
		/bin/su postgres -c "/usr/bin/pg_ctl -s -D ${_PGDATA} status" || exit 1
		;;

	*)
		echo "usage: `basename $0` {start|stop|restart|reload|status}" >&2
		exit 64
		;;
esac
exit 0