// Tells the portal's agreements notice about an agreement recorded somewhere else, so it updates at
// once instead of waiting for its lagging status search.
import { useEffect, useRef } from 'react';
import type { ConsentInstrumentId } from '../../config/consentInstruments';

// `owner` is agreementOwner's: an answer for another viewer, practice or person satisfies no other notice.
type Listener = (instrument: ConsentInstrumentId, owner: string) => void;

const listeners = new Set<Listener>();

export const announceAgreementRecorded = (instrument: ConsentInstrumentId, owner: string): void => {
    listeners.forEach((listener) => listener(instrument, owner));
};

export const useAgreementRecorded = (listener: Listener): void => {
    // Replaced during render, so an event arriving after this render committed is judged by this render's owner.
    const latest = useRef(listener);
    latest.current = listener;
    useEffect(() => {
        const relay: Listener = (instrument, owner) => latest.current(instrument, owner);
        listeners.add(relay);
        return () => {
            listeners.delete(relay);
        };
    }, []);
};