Discriminator in username

ts/state/selectors/username.ts

@@ -0,0 +1,50 @@
+// Copyright 2022 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { createSelector } from 'reselect';
+
+import type { UsernameReservationType } from '../../types/Username';
+import type { StateType } from '../reducer';
+import type {
+  UsernameStateType,
+  UsernameReservationStateType,
+} from '../ducks/username';
+import type {
+  UsernameEditState,
+  UsernameReservationState,
+  UsernameReservationError,
+} from '../ducks/usernameEnums';
+
+export const getUsernameState = (state: StateType): UsernameStateType =>
+  state.username;
+
+export const getUsernameEditState = createSelector(
+  getUsernameState,
+  (state: UsernameStateType): UsernameEditState => state.editState
+);
+
+export const getUsernameReservation = createSelector(
+  getUsernameState,
+  (state: UsernameStateType): UsernameReservationStateType =>
+    state.usernameReservation
+);
+
+export const getUsernameReservationState = createSelector(
+  getUsernameReservation,
+  (reservation: UsernameReservationStateType): UsernameReservationState =>
+    reservation.state
+);
+
+export const getUsernameReservationObject = createSelector(
+  getUsernameReservation,
+  (
+    reservation: UsernameReservationStateType
+  ): UsernameReservationType | undefined => reservation.reservation
+);
+
+export const getUsernameReservationError = createSelector(
+  getUsernameReservation,
+  (
+    reservation: UsernameReservationStateType
+  ): UsernameReservationError | undefined => reservation.error
+);