defmodule Mv.Membership.JoinRequest.Changes.SetConfirmServerMetadata do
  @moduledoc """
  Ash Change that sets server-side metadata for the public :confirm action.

  Client may only send :email, :confirmation_token_hash, :payload (concept §2.3.2).
  This change sets: status, submitted_at, source, schema_version so they cannot be forged.
  """
  use Ash.Resource.Change

  @impl true
  def change(changeset, _opts, _context) do
    changeset
    |> Ash.Changeset.force_change_attribute(:status, "submitted")
    |> Ash.Changeset.force_change_attribute(:submitted_at, DateTime.utc_now())
    |> Ash.Changeset.force_change_attribute(:source, "public_join")
    |> Ash.Changeset.force_change_attribute(:schema_version, 1)
  end
end