simple js event manager

event-manager.js

const $ = require('jquery');

class EventManager {

    constructor(handlers) {
        this._handlers = {};
        if (handlers) {
            $.each(handlers, (name, cb) => {
                this.listen(name, cb);
            });
        }
    }

    listen(eventName, cb) {
        if (typeof eventName === "string") {
            if (!this._handlers[eventName]) {
                this._handlers[eventName] = []
            }

            if ($.isArray(cb)) {
                this._handlers[eventName].push(...cb);
            } else {
                this._handlers[eventName].push(cb);
            }
        } else {
            $.each(eventName, (eventName, cb) => {
                this.listen(eventName, cb);
            });
        }
    }

    trigger(eventName, payload = []) {
        if (!$.isArray(payload)) {
            payload = [payload];
        }
        if (this._handlers[eventName]) {
            this._handlers[eventName].map((handler) => {
                handler(...payload);
            });
        }
    }
}

module.exports = EventManager;