#!/bin/sh

# Update a virtual cluster built by autocluster, with IPv6 addresses

# Copyright (C) Martin Schwenke  2019, 2020

# 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.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, see <http://www.gnu.org/licenses/>.


# Add IPv6 addresses on interfaces eth1, eth2, eth3.  The IPv6
# addresses are calculated from the IPv4 addresses.  The CTDB nodes
# and public_addresses files are updated to contain only the IPv6
# addresses.

# This nasty hack is requird because vagrant-libvirt does not properly
# support IPv6 addresses.

set -eu

if [ $# -ne 1 ] ; then
	echo "usage: ${0} <cluster>"
	exit 1
fi

cluster="$1"

hosts=".autocluster/${cluster}/hosts"
if [ ! -r "$hosts" ] ; then
	echo "error: no file \"${hosts}\""
	exit 1
fi

nodes=".autocluster/${cluster}/nodes"
: >"$nodes"

public_addresses=".autocluster/${cluster}/public_addresses"
: >"$public_addresses"

hosts_ipv6=".autocluster/${cluster}/hosts.ipv6"
echo '# autocluster m1' >"$hosts_ipv6"

maybe_add_ip ()
{
	_host="$1"
	_addr="$2"
	_iface="$3"

	printf '  %s@%s: ' "$_addr" "$_iface"
	_t=$(ssh -n "$_host" ip -o addr show to "${_addr%/*}" | \
		    awk '{print $2}')
	if [ -z "$_t" ] ; then
		ssh -n "$_host" ip addr add "$_addr" dev "$_iface"
		echo '+'
	else
		echo '.'
	fi
}

echo "Confirming IPv6 addresses:"
sort -n "$hosts" |
while read -r ipv4 fqdn host ; do
	case "$ipv4" in
	\#*) continue ;;
	esac

	ipv4_rest="$ipv4"
	a="${ipv4_rest%%.*}"
	ipv4_rest="${ipv4_rest#*.}"
	b="${ipv4_rest%%.*}"
	ipv4_rest="${ipv4_rest#*.}"
	c="${ipv4_rest%%.*}"
	ipv4_rest="${ipv4_rest#*.}"
	d="${ipv4_rest%%.*}"

	echo "${host}:"

	ssh -n "$host" sysctl -q net.ipv6.conf.all.disable_ipv6=0

	#
	# eth1
	#

	eth1_ipv6=$(printf 'fd00:%x:%x:%x::%x/64' "$a" "$b" "$c" "$d")
	case "$host" in
	${cluster}n[0-9]*)
		echo "${eth1_ipv6%/*}" >>"$nodes"
		;;
	esac

	echo "${eth1_ipv6%/*} ${fqdn} ${host}" >>"$hosts_ipv6"

	maybe_add_ip "$host" "$eth1_ipv6" "eth1"

	#
	# eth2
	#

	eth2_c=$((c + 1))
	eth2_ipv6=$(printf 'fd00:%x:%x:%x::%x/64' "$a" "$b" "$eth2_c" "$d")
	case "$host" in
	${cluster}n[0-9]*)
		p_d=$((d + 100))
		p=$(printf 'fd00:%x:%x:%x::%x/64' "$a" "$b" "$eth2_c" "$p_d")
		printf '%s\t%s\n' "$p" "eth2" >>"$public_addresses"
		;;
	esac

	maybe_add_ip "$host" "$eth2_ipv6" "eth2"

	#
	# eth3
	#

	eth3_c=$((c + 2))
	eth3_ipv6=$(printf 'fd00:%x:%x:%x::%x/64' "$a" "$b" "$eth3_c" "$d")
	case "$host" in
	${cluster}n[0-9]*)
		p_d=$((d + 100))
		p=$(printf 'fd00:%x:%x:%x::%x/64' "$a" "$b" "$eth3_c" "$p_d")
		printf '%s\t%s\n' "$p" "eth3" >>"$public_addresses"
		;;
	esac

	maybe_add_ip "$host" "$eth3_ipv6" "eth3"
done

echo
echo "${nodes}:"
cat "$nodes"

echo
echo "${public_addresses}:"
cat "$public_addresses"

echo
echo "${hosts_ipv6}:"
cat "$hosts_ipv6"

echo
echo "Stopping ctdb:"
sort -n "$hosts" |
while read -r ipv4 _ host ; do
	case "$ipv4" in
	\#*) continue ;;
	esac

	case "$host" in
	${cluster}n[0-9]*)
		echo "${host}"
		ssh -n "$host" systemctl stop ctdb
		;;
	esac
done

echo
echo "Determining CTDB configuration directory"
conf=".autocluster/${cluster}/config.yml"
if grep -Fxq 'tarball: null' "$conf" ; then
	# Default
	ctdb_config_dir="/etc/ctdb"
else
	prefix=$(sed -n -e 's|^tarball_install_prefix: *||p' "$conf")
	ctdb_config_dir="${prefix}/etc/ctdb"
fi
echo "$ctdb_config_dir"

echo
echo "Copying configuration files:"
sort -n "$hosts" |
while read -r ipv4 _ host ; do
	case "$ipv4" in
	\#*) continue ;;
	esac

	case "$host" in
	${cluster}n[0-9]*|${cluster}test[0-9]*)
		dst="${host}:${ctdb_config_dir}/nodes"
		echo "$dst"
		scp -q "$nodes" "$dst"
		;;
	esac

	case "$host" in
	${cluster}n[0-9]*)
		dst="${host}:${ctdb_config_dir}/public_addresses"
		echo "$dst"
		scp -q "$public_addresses" "$dst"
		;;
	esac
done

echo
echo "Starting ctdb:"
sort -n "$hosts" |
while read -r ipv4 _ host ; do
	case "$ipv4" in
	\#*) continue ;;
	esac

	case "$host" in
	${cluster}n[0-9]*)
		echo "${host}"
		ssh -n "$host" systemctl start ctdb
		;;
	esac
done

echo
echo "Waiting until healthy:"
sort -n "$hosts" |
while read -r ipv4 _ host ; do
	case "$ipv4" in
	\#*) continue ;;
	esac

	if [ "$host" != "${cluster}n1" ] ; then
		continue
	fi

	timeout=120
	printf '|<%d|' $timeout
	for n in $(seq 1 $timeout) ; do
		if ssh -n "$host" ctdb nodestatus all >/dev/null ; then
			break
		fi

		printf '.'
		sleep 1
	done

	out=$(ssh -n "$host" ctdb nodestatus all 2>&1)
	# shellcheck disable=SC2181
	if [ $? -eq 0 ] ; then
		printf '|%d|\n' "$n"
	else
		printf 'TIMEOUT!\n'
	fi

	echo
	echo "$out"
done