#!/bin/sh
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	See the
# GNU General Public License for more details.


# IMPORTANT!!
# DO NOT RUN THIS IN CRONJOB!

execute_subshell() {
	if [ $# -ne 1 ]; then
		echo "Usage:" "$0" "<function>"
	fi

	for script in /etc/gateway.d/*; do
		(
			# unset function to prevent executing parents shell function
			unset -f "$1"
			. "$script"

			if type "$1" | grep -q "function" ; then
				"$1"
			fi
		)

		if [ $? -ne 0 ]; then
			echo
			echo "Error when executing" "$1" "from" "$(basename "$script")"
			exit 1
		fi
	done
}

configure() {
	echo "This script might remove existing vlans, interfaces, addresses, etc."
	read -r -p "Do you really want to continue? (y/n) " response
	if ! ( [ "$response" == "y" ] || [ "$response" == "Y" ] ); then
		exit 1
	fi

	echo
	execute_subshell configure

	exit 0
}

reload_services() {
	execute_subshell reload
	reload_config
}

apply_changes() {
	execute_subshell apply
	reload_services
	exit 0
}

revert_changes() {
	execute_subshell revert
	exit 0
}

test_changes() {
	reload_services

	sleep 5
	echo "Configuration reloaded. Changes will be reverted in 200s."
	echo "Kill this script to keep changes."
	sleep 200
	echo "Reverting changes.."

	revert_changes
	reload_services
}


usage() {
	echo "Usage: $0 [OPTION]"
	echo
	echo "Options:"
	echo "	-c: configure. No commit, no restart!"
	echo "	-t: test changes. Restarts services, waits up to 200s for SIGINT"
	echo "	-a: apply changes"
	echo "	-r: revert changes"
}


if [ $# != 1 ]; then
	usage; exit 1
fi

case "$1" in
	-c) configure ;;
	-t) test_changes ;;
	-a) apply_changes ;;
	-r) revert_changes ;;
	*) usage; exit 1 ;;
esac