wikimedia/mediawiki-extensions-Wikibase

/**
 * @license GPL-2.0-or-later
 * @author H. Snater < mediawiki@snater.com >
 */
( function () {
    'use strict';

    /**
     * Generator for a Globally Unique IDentifier.
     *
     * @abstract
     * @constructor
     */
    var GuidGenerator = function GuidGenerator() {};

    $.extend( GuidGenerator.prototype, {
        /**
         * Generates and returns a Globally Unique IDentifier.
         *
         * @return {string}
         */
        newGuid: util.abstractMember
    } );

    /**
     * Generates and returns a GUID.
     *
     * @see http://php.net/manual/en/function.com-create-guid.php
     * @return {string}
     */
    module.exports = util.inherit(
        'V4GuidGenerator',
        GuidGenerator, {
            /**
             * Returns a random hexadecimal number in a given range of integers.
             * (see PHP implementation)
             *
             * @param {number} min Minimum number
             * @param {number} max Maximum number
             * @return {string}
             */
            _getRandomHex: function ( min, max ) {
                return ( Math.floor( Math.random() * ( max - min + 1 ) ) + min ).toString( 16 );
            },

            /**
             * @see GuidGenerator
             */
            newGuid: function () {
                var self = this,
                    template = 'xx-x-x-x-xxx',
                    guid = '';

                for ( var i = 0; i < template.length; i++ ) {
                    var character = template.charAt( i );

                    if ( character === '-' ) {
                        guid += '-';
                        continue;
                    }

                    var hex;
                    if ( i === 3 ) {
                        hex = self._getRandomHex( 16384, 20479 );
                    } else if ( i === 4 ) {
                        hex = self._getRandomHex( 32768, 49151 );
                    } else {
                        hex = self._getRandomHex( 0, 65535 );
                    }

                    while ( hex.length < 4 ) {
                        hex = '0' + hex;
                    }

                    guid += hex;
                }

                return guid;
            }
        }
    );

}() );