import string


def validate_cat_name(name, auto_gen=False):
    ALLOWED = set(string.ascii_letters + string.digits)
    if not auto_gen:
        if len(name) < 4 or len(name) > 24:
            return "Your cat's name must be 4-24 characters long."
    else:
        if len(name) > 9:
            return "Your cat's name must be below 9 characters long."
    if not all(c in ALLOWED for c in name):
        return "Your cat's name can only have letters and numbers."
    if not any(c in string.ascii_letters for c in name):
        return "Your cat's name needs at least 1 letter."