edx-platform/xmodule/assets/video/public/js/00_component.js

'use strict';

import _ from 'underscore';


/**
 * Creates a new object with the specified prototype object and properties.
 * @param {Object} o The object which should be the prototype of the
 * newly-created object.
 * @private
 * @throws {TypeError, Error}
 * @return {Object}
 */
let inherit = Object.create || (function() {
    let F = function() {};

    return function(o) {
        if (arguments.length > 1) {
            throw Error('Second argument not supported');
        }
        if (_.isNull(o) || _.isUndefined(o)) {
            throw Error('Cannot set a null [[Prototype]]');
        }
        if (!_.isObject(o)) {
            throw TypeError('Argument must be an object');
        }

        F.prototype = o;

        return new F();
    };
}());

/**
 * Component module.
 * @exports video/00_component.js
 * @constructor
 * @return {jquery Promise}
 */
let Component = function() {
    if ($.isFunction(this.initialize)) {
        // eslint-disable-next-line prefer-spread
        return this.initialize.apply(this, arguments);
    }
};

/**
 * Returns new constructor that inherits form the current constructor.
 * @static
 * @param {Object} protoProps The object containing which will be added to
 * the prototype.
 * @return {Object}
 */
Component.extend = function(protoProps, staticProps) {
    let Parent = this;
    let Child = function() {
        if ($.isFunction(this.initialize)) {
            // eslint-disable-next-line prefer-spread
            return this.initialize.apply(this, arguments);
        }
    };

    // Inherit methods and properties from the Parent prototype.
    Child.prototype = inherit(Parent.prototype);
    Child.constructor = Parent;
    // Provide access to parent's methods and properties
    Child.__super__ = Parent.prototype;

    // Extends inherited methods and properties by methods/properties
    // passed as argument.
    if (protoProps) {
        $.extend(Child.prototype, protoProps);
    }

    // Inherit static methods and properties
    $.extend(Child, Parent, staticProps);

    return Child;
};

export default Component;