Improve logic for app badge count

ts/util/getConversationUnreadCountForAppBadge.ts

@@ -0,0 +1,35 @@
+// Copyright 2022 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import type { ConversationAttributesType } from '../model-types.d';
+import { isConversationMuted } from './isConversationMuted';
+
+export function getConversationUnreadCountForAppBadge(
+  conversation: Readonly<
+    Pick<
+      ConversationAttributesType,
+      'isArchived' | 'markedUnread' | 'muteExpiresAt' | 'unreadCount'
+    >
+  >,
+  canCountMutedConversations: boolean
+): number {
+  const { isArchived, markedUnread, unreadCount } = conversation;
+
+  if (isArchived) {
+    return 0;
+  }
+
+  if (!canCountMutedConversations && isConversationMuted(conversation)) {
+    return 0;
+  }
+
+  if (unreadCount) {
+    return unreadCount;
+  }
+
+  if (markedUnread) {
+    return 1;
+  }
+
+  return 0;
+}