#!/bin/bash


set -eux


[ "${DOMAIN}" ] || {
    echo "Error: you must set \$DOMAIN prior to running this script." >&2
    exit 1
}

[ "${BACKUP_SERVER}" ] || {
    echo "Error: you must set \$BACKUP_SERVER prior to running this script." >&2
    exit 1
}


## rsync
type -p rsync >/dev/null 2>&1 || apt-get install -y rsync </dev/null

## creating rsync user
mkdir -p /var/lib/rsync

getent group rsync >/dev/null ||
    groupadd -r rsync

getent passwd rsync >/dev/null ||
    useradd -r rsync -d /var/lib/rsync -g rsync

chown rsync:rsync /var/lib/rsync

## rsync ssh key creation
[ -e /var/lib/rsync/.ssh/id_rsa ] ||
    su -c 'ssh-keygen -t rsa -N "" -f ~/.ssh/id_rsa -q -C rsync@'"$DOMAIN" - rsync

dest="$BACKUP_SERVER"
if [[ "$dest" == *"/"* ]]; then
    dest="${dest%/*}"
fi

if [[ "$dest" == *":"* ]]; then
    ssh_options+=("-p" "${dest#*:}")
    dest="${dest%%:*}"
fi

ssh-keyscan "${ssh_options[@]}" -H "${dest}" > /var/lib/rsync/.ssh/known_hosts

apt-get install kal-shlib-process </dev/null
ln -sf "$PWD/resources/bin/mirror-dir" /usr/local/sbin/mirror-dir



if ! [ -e /etc/mirror-dir/config.yml ]; then
    mkdir -p /etc/mirror-dir
    cat <<EOF > /etc/mirror-dir/config.yml
default:
  sources:
  - /etc
EOF
fi

cat <<EOF > /etc/cron.d/mirror-dir
SHELL=/bin/bash
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin

$((RANDOM % 60)) * * * *   root   mirror-dir -h "$DOMAIN" -d "$BACKUP_SERVER" -u rsync 2>&1 | logger -t mirror-dir

EOF