#!/bin/sh
set -e

die() {
	echo "$*" 1>&2
	exit 1
}

[ -z "$1" ] && die "usage: $0 HOST"

NAME="$1"
DATADIR=${DATADIR:-/etc/wg}
HOSTFILE=${HOSTFILE:-${DATADIR}/hosts}

# Detect if name in use
if grep -q "^$NAME[[:space:]]" "$HOSTFILE"; then
	die "hostname $NAME taken"
fi

# Get public and private keys
CONF="$DATADIR/$NAME"
mkdir -p "$CONF"
openssl rand -base64 32 > "$CONF/private.key"

ifconfig wg9 destroy 2>/dev/null   || true
ifconfig wg9 create wgport 13421 wgkey "$(cat "$CONF/private.key")"
ifconfig wg9 | grep wgpubkey | cut -d ' ' -f 2 > "$CONF/public.key"
ifconfig wg9 destroy 2>/dev/null   || true

# Assign an IP
CUR=$(tail -n 1 "$HOSTFILE" | cut -d. -f 4)
NEXT=$((CUR + 1))
echo "$NAME	10.6.6.$NEXT" >> "$HOSTFILE"

# Generate the config
cat <<EOM > "$CONF/client.conf"
# public key: $(cat "$CONF/public.key")
[Interface]
PrivateKey = $(cat "$CONF/private.key")
Address = 10.6.6.$NEXT/24

[Peer]
PublicKey = JpsSfrcrhCcTR5bybV9YQaAV60A12heinyAiSbMK3ng=
AllowedIPs = 10.6.6.1/32
Endpoint = 45.79.221.98:7149
EOM

# Lastly, append to /etc/hostname.wg0 and restart it
cat <<EOM >> /etc/hostname.wg0
wgpeer $(cat "$CONF/public.key") wgaip 10.6.6.$NEXT/32
EOM

sh /etc/netstart