init_network

#!/usr/bin/env bash

# Settings
HOST_REGEX='[0-9\.*] benchbot_'

# Ensure a valid remote has been provided
remote_address="$1"
if [ -z "$remote_address" ]; then
  printf "%s\n" "ERROR: No remote BenchBot address supplied"
  exit 1
elif [ "$(ping -c 1 "$remote_address" &>/dev/null; echo $?)" -ne 0 ]; then
  printf "%s\n" \
    "ERROR: Pinging remote BenchBot address ($remote_address) failed"
  exit 1
fi

# Grab the list of hosts from the remote & local
user="${2:-benchbot}"
printf "%s\n" "Pulling benchbot_ hosts via SSH from '$user@$remote_address' ..."
remote_hosts=$(ssh "$user"@"$remote_address" 'cat /etc/hosts' | \
  grep "$HOST_REGEX")
printf "\nFound the following relevant remote hosts:\n%s\n" \
  "$remote_hosts"
local_hosts=$(cat /etc/hosts | grep "$HOST_REGEX")
printf "\nREPLACING the following relevant local hosts:\n%s\n" \
  "$local_hosts"

# Replace all matching hosts on local machine with those from the remote
# BenchBot machine
sudo sed -i "/$HOST_REGEX/d" /etc/hosts
echo "$remote_hosts" | sudo tee -a /etc/hosts > /dev/null
printf "\nDone.\n"

# Add the route for the host to the current network interface
# TODO probably shouldn't make sure a sweeping assumption in pulling gateway...
hosts_mask=$(echo "$remote_hosts" | head -n 1 | \
  sed 's/\([0-9]*\.[0-9]*\.[0-9]*\.\).*/\10\/24/')
net_dev=$(ip a | awk '/state UP/ {print $2}' | sed 's/:$//')
printf "\n%s %s\n" "Adding route for hosts using the subnet mask" \
  "'$hosts_mask' on device '$net_dev' ..."
sudo ip route add "$hosts_mask" via "$remote_address" dev "$net_dev"
printf "Done.\n"