Improve experience for contacts without signal accounts

ts/util/isConversationSMSOnly.ts

@@ -0,0 +1,27 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { isConversationUnregistered } from './isConversationUnregistered';
+
+export type MinimalConversationType = Readonly<{
+  type?: string;
+  e164?: string;
+  uuid?: string;
+  discoveredUnregisteredAt?: number;
+}>;
+
+export function isConversationSMSOnly(
+  conversation: MinimalConversationType
+): boolean {
+  const { e164, uuid, type } = conversation;
+  // `direct` for redux, `private` for models and the database
+  if (type !== 'direct' && type !== 'private') {
+    return false;
+  }
+
+  if (e164 && !uuid) {
+    return true;
+  }
+
+  return isConversationUnregistered(conversation);
+}