meta/lib/meta_web/controllers/support_controller.ex

defmodule MetaWeb.SupportController do
  use MetaWeb, :controller

  alias Meta.SupportRequest
  alias Meta.Captcha

  def new(conn, _params) do
    {captcha_text, captcha_result} = Captcha.generate()

    conn
    |> assign(:request_changeset, SupportRequest.changeset(%SupportRequest{}, %{}))
    |> assign(:captcha, captcha_text)
    |> put_session(:captcha, captcha_result)
    |> render("new.html")
  end

  def create(conn, %{"support_request" => raw} = params) do
    attrs = raw |> Map.put("expected_captcha", get_session(conn, :captcha))
    action = SupportRequest.changeset(%SupportRequest{}, attrs)
             |> Ecto.Changeset.apply_action(:update)

    case action do
      {:ok, request} ->
        # FIXME: check for error?
        SupportRequest.send(request)

        conn
        |> put_flash(:info, "Request has been sent. We'll come back to you.")
        |> redirect(to: Routes.page_path(conn, :index))

      {:error, changeset} ->
        {captcha_text, captcha_result} = Captcha.generate()

        conn
        |> assign(:request_changeset, changeset)
        |> assign(:captcha, captcha_text)
        |> put_session(:captcha, captcha_result)
        |> render("new.html")
    end
  end
end