#! /bin/bash

set -e
set -x
service postgresql start
thisback="/mnt/back/$(date -u +%Y%m%d%H%M%S).dump"
rm -rf "$thisback" || true
mkdir -p "$(dirname "$thisback")"
pg_dump postgres://ffly:pwd@localhost/fireflyiii --clean > "$thisback"
service postgresql start
n=$(ls /mnt/back | wc -l)
if ((n<=25)); then
   echo "No old backups to purge" >&2
   exit 0
fi
((m=n-25))
stale=($(find /mnt/back/ -mindepth 1 -maxdepth 1 | sort | head -n $m))
echo "Purging: rm -rf ${stale[@]}" >&2
rm -rf "${stale[@]}"
remaining=($(find /mnt/back/ -mindepth 1 -maxdepth 1 | sort))
echo "Remains: ${remaining[@]}" >&2