setInterval with random intervals (in given bounds)

setRandomInterval

/**
 * @author Konstantin Kitmanov <doctor.hogart@gmail.com>
 * @license MIT
 */

(function (root, factory) {
    if (typeof define === 'function' && define.amd) { // AMD anonymous module
        define([], factory);
    } else if (typeof exports === 'object') { // NodeJS/CommonJS-like module
        module.exports = factory();
    } else { // Browser globals (root is window)
        root.randomInterval = factory();
    }
}(this, function () {
    'use strict';

    /**
     * Return random float number between min and max
     * @param {Number} min inclusive
     * @param {Number} max exclusive
     * @returns {Number} random float number
     */
    function randomInRange (min, max) {
        return Math.random() * (max - min) + min;
    }

    /**
     * Calls `callback` after random timeout between `min` and `max`
     * @param {Function} callback timeout callback
     * @param {Number} min minimal timeout
     * @param {Number} max maximal timeout
     * @returns {Function} function that cancels timeout
     */
    function setRandomTimeout (callback, min, max) {
        var timeout = setTimeout(callback, Math.floor(randomInRange(min, max)));

        return function () {
            clearTimeout(timeout);
        };
    }

    /**
     * Calls `callback` in random intervals between `min` and `max`
     * @param {Function} callback interval callback
     * @param {Number} min minimal interval
     * @param {Number} max maximal interval
     * @returns {Function} function that cancels interval
     */
    function setRandomInterval (callback, min, max) {
        var currentTimeout;

        function onTimeout () {
            callback();
            currentTimeout = setRandomTimeout(onTimeout, min, max);
        }

        currentTimeout = setRandomTimeout(onTimeout, min, max);

        return function () {
            currentTimeout();
        };
    }

    setRandomInterval.setRandomTimeout = setRandomTimeout;
    setRandomInterval.randomInRange = randomInRange;

    return setRandomInterval;
}));