#!/bin/sh
set -euo pipefail


usage() {
	cat <<-'EOF'
		Usage:
		  datomic backup DBFILE TODIR
		  datomic gc     DBFILE
	EOF
}


ACTION="${1:-}"
DBFILE="${2:-}"
TODIR="${3:-}"

if [ -z "$ACTION" ]; then
	echo 'Missing ACTION.' >&2
	usage >&2
	exit 2
fi

if [ -z "$DBFILE" ]; then
	echo 'Missing DBFILE.' >&2
	usage >&2
	exit 2
fi

if [ "$ACTION" = 'backup' ] && [ -z "$TODIR" ]; then
	echo 'Missing TODIR.' >&2
	usage >&2
	exit 2
fi



lastroot() (
	cd "$TODIR"/datomic/roots
	find * | sort -n | tail -n1
)

backupcmd() {
	java \
		-server                                  \
		-Xms4g                                   \
		-Xmx4g                                   \
		--class-path '@SYSCONFDIR@/:@JAVADIR@/*' \
		clojure.main                             \
		-m backup                                \
		"$@"
}


case "$ACTION" in
	(backup)
		backupcmd backup datomic:sql://app?jdbc:sqlite:"$DBFILE" file:"$TODIR"/datomic
		backupcmd verify  file:"$TODIR"/datomic true "$(lastroot)"
		sqlite3 "$DBFILE" ".backup '$TODIR/sqlite.db'"
		{
			sqlite3 "$DBFILE" .dump > "$TODIR"/dump.sql.next
			mv "$TODIR"/dump.sql.next "$TODIR"/dump.sql
		}
		{
			sqlite3 "$TODIR"/restored.db < @SYSCONFDIR@/init.sql > /dev/null
			backupcmd restore file:"$TODIR"/datomic datomic:sql://app?jdbc:sqlite:"$TODIR"/restored.db
		}
		;;
	(gc)
		exec java \
			-server                                  \
			-Xms4g                                   \
			-Xmx4g                                   \
			--class-path '@SYSCONFDIR@/:@JAVADIR@/*' \
			clojure.main                             \
			-m datomic.tools.gc-db                   \
			datomic:sql://app?jdbc:sqlite:"$DBFILE"  \
			"$(date --date="$(date +'%Y-%m-01') - 3 months" -Is)"
		;;
	(*)
		printf 'Bad ACTION: "%s"\n' "$ACTION" >&2
		usage >&2
		exit 2
		;;
esac