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src/utils/uuid.js

/*
 * BSD 3-Clause License
 *
 * Copyright (c) 2018, MapCreator
 * All rights reserved.
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 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
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 *  Redistributions of source code must retain the above copyright notice, this
 *   list of conditions and the following disclaimer.
 *
 *  Redistributions in binary form must reproduce the above copyright notice,
 *   this list of conditions and the following disclaimer in the documentation
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 *
 *  Neither the name of the copyright holder nor the names of its
 *   contributors may be used to endorse or promote products derived from
 *   this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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 */

import StaticClass from './StaticClass';

/**
 * UUID util class
 * @static
 * @private
 */
export default class Uuid extends StaticClass {
  /**
   * Generate a UUID4 string
   * @returns {string} - Uuid
   */
  static uuid4 () {
    let d = new Date().getTime();

    if (typeof performance !== 'undefined' && typeof performance.now === 'function') {
      d += performance.now(); // use high-precision timer if available
    }

    return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, c => {
      const r = (d + (Math.random() * 16)) % 16 | 0;

      d = Math.floor(d / 16);

      return (c === 'x' ? r : (r & 0x3) | 0x8).toString(16);
    });
  }

  /**
   * Empty uuid as per spec
   * @returns {string} - Uuid
   */
  static nil () {
    return '0000000-0000-0000-0000-000000000000';
  }
}