RocketChat/Rocket.Chat

import { useSyncExternalStore } from 'use-sync-external-store/shim';

import { useChat } from '../contexts/ChatContext';

export const useFirstUnreadMessageId = (): string | undefined => {
    const chat = useChat();

    if (!chat) {
        throw new Error('useFirstUnreadMessageId must be used within a ChatContextProvider');
    }

    return useSyncExternalStore(chat.readStateManager.onUnreadStateChange, chat.readStateManager.getFirstUnreadRecordId);
};