Usernames: Create/update/delete in profile editor

ts/services/writeUsername.ts

@@ -0,0 +1,38 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import dataInterface from '../sql/Client';
+import { handleMessageSend } from '../util/handleMessageSend';
+
+export async function writeUsername({
+  username,
+  previousUsername,
+}: {
+  username: string | undefined;
+  previousUsername: string | undefined;
+}): Promise<void> {
+  const me = window.ConversationController.getOurConversationOrThrow();
+  await me.getProfiles();
+
+  if (me.get('username') !== previousUsername) {
+    throw new Error('Username has changed on another device');
+  }
+
+  if (username) {
+    await window.textsecure.messaging.putUsername(username);
+  } else {
+    await window.textsecure.messaging.deleteUsername();
+  }
+
+  // Update backbone, update DB, then tell linked devices about profile update
+  me.set({
+    username,
+  });
+
+  dataInterface.updateConversation(me.attributes);
+
+  await handleMessageSend(
+    window.textsecure.messaging.sendFetchLocalProfileSyncMessage(),
+    { messageIds: [], sendType: 'otherSync' }
+  );
+}