cattle-reset-elapsed() {
  (( last_cmd_at = SECONDS ))
}

cattle-increase-timeout() {
  (( timeout += 3600 ))
}

cattle-ping-timer() {
  kill -USR1 "$reaper_pid"
}

cattle-ping-reaper() {
  kill -USR2 "$reaper_pid"
}

cattle-slay-reaper() {
  kill -KILL "$reaper_pid"
}

cd() {
  command cd "$@"
  printf '\033]1337;CurrentDir=%s\007' "$PWD"
  printf %s "$PWD" > /tmp/iterm2-prev-dir.txt
}

{
  trap true EXIT # A permanently temporary workaround, since ^C outside of a
                 # command appears to propagate to the child process.
  trap cattle-reset-elapsed USR1
  trap cattle-increase-timeout USR2
  last_cmd_at=0 timeout=3600

  while sleep 10; do
    (( elapsed = SECONDS - last_cmd_at ))

    if (( elapsed > timeout )); then
      kill -KILL "$$"
      exit
    fi
  done
} 2> /dev/null &

reaper_pid=$! PROMPT_COMMAND+=(cattle-ping-timer)
trap cattle-slay-reaper EXIT

if [[ -f /tmp/iterm2-prev-dir.txt ]]; then
  dir=$(</tmp/iterm2-prev-dir.txt)

  if [[ -d $dir ]]; then
    command cd "$dir"
  fi
fi