defmodule MvWeb.Emails.JoinAlreadyMemberEmail do
  @moduledoc """
  Sends an email when someone submits the join form with an address that is already a member.

  Used for anti-enumeration: the UI shows the same success message; only the email
  informs the recipient. Uses the unified email layout.
  """
  use Gettext, backend: MvWeb.Gettext, otp_app: :mv

  alias MvWeb.Emails.JoinEmail

  @doc """
  Sends the "already a member" notice to the given address.

  Returns `{:ok, email}` on success, `{:error, reason}` on delivery failure.
  """
  def send(email_address) when is_binary(email_address) do
    subject = gettext("Membership application – already a member")

    JoinEmail.deliver(email_address, "join_already_member.html", subject)
  end
end