bona/src/base/index.js

Super lightweight microframework focused on static websites and landing pages.

/**
 * @typedef {Object} BonaEventOptions
 * @property {boolean} [once] Trigger callback once.
 */

export default class Base {
    constructor() {
        this._events = {};
    }

    /**
     * Attach an event handler function.
     *
     * @param {string} event Event name.
     * @param {function} callback Callback.
     * @param {BonaEventOptions} [options] Options.
     */
    on(event, callback, options = {}) {
        if (!this._events[event]) this._events[event] = [];
        this._events[event].push({callback, options});
    }

    /**
     * Remove an event handler.
     *
     * @param {string} event Event name.
     * @param {function} [callback] Callback.
     */
    off(event, callback) {
        if (callback) {
            this._events[event] = this._events[event].filter((e) => e.callback !== callback);
        } else {
            this._events[event] = [];
        }
    }

    /**
     * Execute all handlers for the given event type.
     *
     * @param {string} event Event name.
     * @param params Extra parameters.
     */
    trigger(event, ...params) {
        if (!this._events[event]) return;
        this._events[event].forEach((e) => {
            e.callback.call(this, ...params);
            if (e.options.once) this.off(event, e.callback);
        });
    }
}