/**

 * Copyright (c) Meta Platforms, Inc. and affiliates.

 *

 * This source code is licensed under the MIT license found in the

 * LICENSE file in the root directory of this source tree.

 *

 * @flow

 */

import hasOwnProperty from 'shared/hasOwnProperty';

/* eslint-disable max-len */

const ATTRIBUTE_NAME_START_CHAR =

  ':A-Z_a-z\\u00C0-\\u00D6\\u00D8-\\u00F6\\u00F8-\\u02FF\\u0370-\\u037D\\u037F-\\u1FFF\\u200C-\\u200D\\u2070-\\u218F\\u2C00-\\u2FEF\\u3001-\\uD7FF\\uF900-\\uFDCF\\uFDF0-\\uFFFD';

/* eslint-enable max-len */

export const ATTRIBUTE_NAME_CHAR: string =

  ATTRIBUTE_NAME_START_CHAR + '\\-.0-9\\u00B7\\u0300-\\u036F\\u203F-\\u2040';

const VALID_ATTRIBUTE_NAME_REGEX: RegExp = new RegExp(

  '^[' + ATTRIBUTE_NAME_START_CHAR + '][' + ATTRIBUTE_NAME_CHAR + ']*$',

);

const illegalAttributeNameCache: {[string]: boolean} = {};

const validatedAttributeNameCache: {[string]: boolean} = {};

export default function isAttributeNameSafe(attributeName: string): boolean {

  if (hasOwnProperty.call(validatedAttributeNameCache, attributeName)) {

    return true;

  }

  if (hasOwnProperty.call(illegalAttributeNameCache, attributeName)) {

    return false;

  }

  if (VALID_ATTRIBUTE_NAME_REGEX.test(attributeName)) {

    validatedAttributeNameCache[attributeName] = true;

    return true;

  }

  illegalAttributeNameCache[attributeName] = true;

  if (__DEV__) {

    console.error('Invalid attribute name: `%s`', attributeName);

  }

  return false;

}