locutus/esm/php/array/shuffle.js

Locutus other languages' standard libraries to JavaScript for fun and educational purposes

import { ini_get } from "../info/ini_get.js";
export function shuffle(inputArr) {
    //  discuss at: https://locutus.io/php/shuffle/
    // original by: Jonas Raoni Soares Silva (https://www.jsfromhell.com)
    //  revised by: Kevin van Zonneveld (https://kvz.io)
    //  revised by: Brett Zamir (https://brett-zamir.me)
    // improved by: Brett Zamir (https://brett-zamir.me)
    //   example 1: var $data = {5:'a', 2:'3', 3:'c', 4:5, 'q':5}
    //   example 1: ini_set('locutus.sortByReference', true)
    //   example 1: shuffle($data)
    //   example 1: var $result = $data.q
    //   returns 1: 5
    const valArr = [];
    let k = '';
    let i = 0;
    let sortByReference = false;
    let populateArr = [];
    for (k in inputArr) {
        // Get key and value arrays
        if (inputArr.hasOwnProperty(k)) {
            const value = inputArr[k];
            if (value === undefined) {
                continue;
            }
            valArr.push(value);
            if (sortByReference) {
                delete inputArr[k];
            }
        }
    }
    valArr.sort(function () {
        return 0.5 - Math.random();
    });
    const iniVal = ini_get('locutus.sortByReference') || 'on';
    sortByReference = iniVal === 'on';
    populateArr = sortByReference ? inputArr : populateArr;
    for (i = 0; i < valArr.length; i++) {
        // Repopulate the old array
        if (Array.isArray(populateArr)) {
            const value = valArr[i];
            if (value === undefined) {
                continue;
            }
            populateArr[i] = value;
        }
        else {
            const value = valArr[i];
            if (value === undefined) {
                continue;
            }
            populateArr[String(i)] = value;
        }
    }
    return sortByReference || populateArr;
}