+ # POST /ostatus_subscribe
+ #
+ # step 2
+ # checks TOTP code. otherwise displays form with errors
+ #
+ def do_follow(conn, %{"mfa" => %{"code" => code, "token" => token, "id" => id}}) do
+ with {_, %User{} = followee} <- {:fetch_user, User.get_cached_by_id(id)},
+ {_, _, {:ok, %{user: user}}} <- {:mfa_token, followee, MFA.Token.validate(token)},
+ {_, _, _, {:ok, _}} <-
+ {:verify_mfa_code, followee, token, TOTPAuthenticator.verify(code, user)},
+ {:ok, _, _, _} <- CommonAPI.follow(user, followee) do
+ redirect(conn, to: "/users/#{followee.id}")
+ else
+ error ->
+ handle_follow_error(conn, error)
+ end
+ end
+
+ def do_follow(%{assigns: %{user: nil}} = conn, _) do
+ Logger.debug("Insufficient permissions: follow | write:follows.")
+ render(conn, "followed.html", %{error: "Insufficient permissions: follow | write:follows."})
+ end
+
+ defp handle_follow_error(conn, {:mfa_token, followee, _} = _) do
+ render(conn, "follow_login.html", %{error: "Wrong username or password", followee: followee})
+ end
+
+ defp handle_follow_error(conn, {:verify_mfa_code, followee, token, _} = _) do
+ render(conn, "follow_mfa.html", %{
+ error: "Wrong authentication code",
+ followee: followee,
+ mfa_token: token
+ })
+ end
+
+ defp handle_follow_error(conn, {:mfa_required, followee, user, _} = _) do
+ {:ok, %{token: token}} = MFA.Token.create(user)
+ render(conn, "follow_mfa.html", %{followee: followee, mfa_token: token, error: false})
+ end
+