When incoming message should've been sealed sender, reply with profile key

ts/util/shouldRespondWithProfileKey.ts

@@ -0,0 +1,36 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { MessageModel } from '../models/messages';
+import { assert } from './assert';
+
+export async function shouldRespondWithProfileKey(
+  message: MessageModel
+): Promise<boolean> {
+  if (!message.isIncoming() || message.get('unidentifiedDeliveryReceived')) {
+    return false;
+  }
+
+  const sender = message.getContact();
+  if (!sender) {
+    assert(
+      false,
+      'MessageModel#shouldRespondWithProfileKey had no sender. Returning false'
+    );
+    return false;
+  }
+
+  if (sender.isMe() || !sender.getAccepted() || sender.isBlocked()) {
+    return false;
+  }
+
+  // We do message check in an attempt to avoid a database lookup. If someone was EVER in
+  //   a shared group with us, we should've shared our profile key with them in the past,
+  //   so we should respond with a profile key now.
+  if (sender.get('sharedGroupNames')?.length) {
+    return true;
+  }
+
+  await sender.updateSharedGroups();
+  return Boolean(sender.get('sharedGroupNames')?.length);
+}