stream-chat-react/dist/components/MessageList/hooks/useLastDeliveredData.js

React components to create chat conversations or livestream style chat

import { useCallback, useEffect, useState } from 'react';
export const useLastDeliveredData = (props) => {
    const { channel, lastOwnMessage, messages, returnAllReadData } = props;
    const calculateForAll = useCallback(() => messages.reduce((acc, msg) => {
        acc[msg.id] = channel.messageReceiptsTracker.deliveredForMessage({
            msgId: msg.id,
            timestampMs: msg.created_at.getTime(),
        });
        return acc;
    }, {}), [channel, messages]);
    const calculateForLastOwn = useCallback(() => {
        if (!lastOwnMessage)
            return {};
        return {
            [lastOwnMessage.id]: channel.messageReceiptsTracker.deliveredForMessage({
                msgId: lastOwnMessage.id,
                timestampMs: lastOwnMessage.created_at.getTime(),
            }),
        };
    }, [channel, lastOwnMessage]);
    const [deliveredTo, setDeliveredTo] = useState(returnAllReadData ? calculateForAll : calculateForLastOwn);
    useEffect(() => {
        if (!returnAllReadData)
            return;
        setDeliveredTo(calculateForAll);
        return channel.on('message.delivered', () => setDeliveredTo(calculateForAll))
            .unsubscribe;
    }, [channel, calculateForAll, returnAllReadData]);
    useEffect(() => {
        if (returnAllReadData)
            return;
        else
            setDeliveredTo(calculateForLastOwn);
        return channel.on('message.delivered', () => setDeliveredTo(calculateForLastOwn))
            .unsubscribe;
    }, [channel, calculateForLastOwn, returnAllReadData]);
    return deliveredTo;
};