#!/usr/bin/env sh

# Usage:
# postgres_backup.sh [man]		//Manual backup
# postgres_backup.sh auto		//Auto backup (separate backup location)
# postgres_backup.sh [auto|man] debug	//Outputs success messages to STDOUT

# CONFIG
### Example Config File ############
###
### PORT=5432
### DIR=/var/lib/pgsql/backup
### COMPRESSION=zstd
### COMP_LEVEL=14
### THREADS=2
###
####################################

source ${HOME}/.postgres_backup.conf
# END CONFIG


## Check if automated, set appropriate directory
[ "$1" = "auto" ] && DIR=${DIR}/auto || DIR=${DIR}/manual

## Set date for timestamp
DATE=$(date +%Y%m%d-%H%M)

## Get list of DBs
list_db=$(psql -p${PORT} -U postgres -t -c 'select datname from pg_database;' | grep -v 'template0\|template1\|postgres' | sed '/^$/d')

case $COMPRESSION in
	xz)
		[ "$2" = "debug" ] && echo "Backed up globals using $COMPRESSION -${COMP_LEVEL}"
		pg_dumpall -p${PORT} -g | xz -T${THREADS} -${COMP_LEVEL} - > ${DIR}/globals_${DATE}.dmp.xz
		[ "$2" = "debug" ] && echo "Starting DB dump loop..."
		for db in $list_db; do
			pg_dump -O $db | xz -T${THREADS} -${COMP_LEVEL} - > ${DIR}/${db}-${DATE}.dmp.xz
			[ "$2" = "debug" ] && echo "Backed up $db using $COMPRESSION -${COMP_LEVEL}"
		done
		;;
	zstd)
		[ "$2" = "debug" ] && echo "Backed up globals using $COMPRESSION -${COMP_LEVEL}"
		pg_dumpall -p${PORT} -g | zstd -T${THREADS} -${COMP_LEVEL} -z - > ${DIR}/globals_${DATE}.dmp.zst
		[ "$2" = "debug" ] && echo "Starting DB dump loop..."
		for db in $list_db; do
			pg_dump -O $db | zstd -T${THREADS} -${COMP_LEVEL} -z - > ${DIR}/${db}-${DATE}.dmp.zst
			[ "$2" = "debug" ] && echo "Backed up $db using $COMPRESSION -${COMP_LEVEL}"
		done
		;;
	*)
		echo "ERROR 11: Compression not configured correctly!" >2
		exit 11
		;;
esac

exit 0