#!/usr/bin/env bash

(
  while true; do
    id=$(
      cat /dev/urandom |
      LC_ALL=C tr -cd A-HJ-NP-Z2-9 |
      fold -w4 |
      grep '[A-Z]' |
      grep '[0-9]' |
      head -n1
    )

    [[ -e src/$id.yaml ]] || break
  done

  echo "$id"
)