RocketChat/Rocket.Chat

import { Emitter } from '@rocket.chat/emitter';
import type { Keys as IconName } from '@rocket.chat/icons';
import type * as UiKit from '@rocket.chat/ui-kit';

export type LegacyBannerPayload = {
    id: string;
    closable?: boolean;
    title?: string | (() => string);
    text?: string | (() => string);
    html?: string | (() => string);
    icon?: IconName;
    modifiers?: ('large' | 'danger')[];
    timer?: number;
    action?: () => Promise<void> | void;
    onClose?: () => Promise<void> | void;
};

type BannerPayload = LegacyBannerPayload | UiKit.BannerView;

export const isLegacyPayload = (payload: BannerPayload): payload is LegacyBannerPayload => !('blocks' in payload);

const queue: BannerPayload[] = [];
const emitter = new Emitter<{
    'update': undefined;
    'update-first': undefined;
}>();

export const firstSubscription = [
    (callback: () => void): (() => void) => emitter.on('update-first', callback),
    (): BannerPayload | null => queue[0] ?? null,
] as const;

export const open = (payload: BannerPayload): void => {
    let index = queue.findIndex((_payload) => {
        if (isLegacyPayload(_payload) && isLegacyPayload(payload)) {
            return _payload.id === payload.id;
        }

        if (!isLegacyPayload(_payload) && !isLegacyPayload(payload)) {
            return _payload.viewId === payload.viewId;
        }

        return false;
    });

    if (index === -1) {
        index = queue.length;
    }

    queue[index] = payload;

    emitter.emit('update');

    if (index === 0) {
        emitter.emit('update-first');
    }
};

export const closeById = (id: string): void => {
    const index = queue.findIndex((banner) => {
        if (!isLegacyPayload(banner)) {
            return banner.viewId === id;
        }
        return banner.id === id;
    });

    if (index < 0) {
        return;
    }

    queue.splice(index, 1);
    emitter.emit('update');
    index === 0 && emitter.emit('update-first');
};

export const close = (): void => {
    queue.shift();
    emitter.emit('update');
    emitter.emit('update-first');
};

export const clear = (): void => {
    queue.splice(0, queue.length);
    emitter.emit('update');
    emitter.emit('update-first');
};