RocketChat/Rocket.Chat

import { isOmnichannelRoom } from '@rocket.chat/core-typings';
import type { IUser, IRoom } from '@rocket.chat/core-typings';
import { Users } from '@rocket.chat/models';
import { Meteor } from 'meteor/meteor';

import { settings } from '../../../../../app/settings/server';
import { callbacks } from '../../../../../lib/callbacks';
import { getMaxNumberSimultaneousChat } from '../lib/Helper';

callbacks.add(
    'beforeJoinRoom',
    async (user: IUser, room?: IRoom): Promise<IUser> => {
        if (!settings.get('Livechat_waiting_queue')) {
            return user;
        }

        if (!room || !isOmnichannelRoom(room)) {
            return user;
        }

        const { departmentId } = room;
        const maxNumberSimultaneousChat = await getMaxNumberSimultaneousChat({
            agentId: user._id,
            departmentId,
        });

        if (maxNumberSimultaneousChat === 0) {
            return user;
        }

        const userSubs = await Users.getAgentAndAmountOngoingChats(user._id);
        if (!userSubs) {
            return user;
        }

        const { queueInfo: { chats = 0 } = {} } = userSubs;
        if (maxNumberSimultaneousChat <= chats) {
            throw new Meteor.Error('error-max-number-simultaneous-chats-reached', 'Not allowed');
        }

        return user;
    },
    callbacks.priority.MEDIUM,
    'livechat-before-join-room',
);