#!/bin/sh -e


pre_install() {
	ND="/etc/nginx"
	SITES_ENABLED="$ND/sites-enabled"
	SITES_AVAILABLE="$ND/sites-available"
	GRAFANA_CONF="grafana"
	GRAFANA_USER="grafana"
	GRAFANA_GROUP="grafana"

	if ! getent group $GRAFANA_GROUP >/dev/null; then
		groupadd -r $GRAFANA_GROUP
	else
		echo "$GRAFANA_GROUP group already exists"
	fi
	if ! getent passwd $GRAFANA_USER >/dev/null; then
		useradd -g $GRAFANA_GROUP -d /usr/share/grafana -M -r --shell /bin/false $GRAFANA_USER
	else
		echo "$GRAFANA_USER user already exists"
	fi

	if [ -f "$SITES_ENABLED/$GRAFANA_CONF" ] ; then
		cp -L $SITES_ENABLED/$GRAFANA_CONF $SITES_AVAILABLE/${GRAFANA_CONF}_bak
		rm -v $SITES_ENABLED/$GRAFANA_CONF
	fi
}


case "$1" in
	upgrade|install)
		pre_install
		;;

	abort-upgrade)
		;;

	*)
		echo "preinst was called with unknown argument '$1'" >&2
		exit 1
		;;
esac
