/**

 * 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.

 */

import {canUseDOM} from 'shared/ExecutionEnvironment';

/**

 * Generate a mapping of standard vendor prefixes using the defined style property and event name.

 *

 * @param {string} styleProp

 * @param {string} eventName

 * @returns {object}

 */

function makePrefixMap(styleProp, eventName) {

  const prefixes = {};

  prefixes[styleProp.toLowerCase()] = eventName.toLowerCase();

  prefixes['Webkit' + styleProp] = 'webkit' + eventName;

  prefixes['Moz' + styleProp] = 'moz' + eventName;

  return prefixes;

}

/**

 * A list of event names to a configurable list of vendor prefixes.

 */

const vendorPrefixes = {

  animationend: makePrefixMap('Animation', 'AnimationEnd'),

  animationiteration: makePrefixMap('Animation', 'AnimationIteration'),

  animationstart: makePrefixMap('Animation', 'AnimationStart'),

  transitionend: makePrefixMap('Transition', 'TransitionEnd'),

};

/**

 * Event names that have already been detected and prefixed (if applicable).

 */

const prefixedEventNames = {};

/**

 * Element to check for prefixes on.

 */

let style = {};

/**

 * Bootstrap if a DOM exists.

 */

if (canUseDOM) {

  style = document.createElement('div').style;

  // On some platforms, in particular some releases of Android 4.x,

  // the un-prefixed "animation" and "transition" properties are defined on the

  // style object but the events that fire will still be prefixed, so we need

  // to check if the un-prefixed events are usable, and if not remove them from the map.

  if (!('AnimationEvent' in window)) {

    delete vendorPrefixes.animationend.animation;

    delete vendorPrefixes.animationiteration.animation;

    delete vendorPrefixes.animationstart.animation;

  }

  // Same as above

  if (!('TransitionEvent' in window)) {

    delete vendorPrefixes.transitionend.transition;

  }

}

/**

 * Attempts to determine the correct vendor prefixed event name.

 *

 * @param {string} eventName

 * @returns {string}

 */

function getVendorPrefixedEventName(eventName) {

  if (prefixedEventNames[eventName]) {

    return prefixedEventNames[eventName];

  } else if (!vendorPrefixes[eventName]) {

    return eventName;

  }

  const prefixMap = vendorPrefixes[eventName];

  for (const styleProp in prefixMap) {

    if (prefixMap.hasOwnProperty(styleProp) && styleProp in style) {

      return (prefixedEventNames[eventName] = prefixMap[styleProp]);

    }

  }

  return eventName;

}

export default getVendorPrefixedEventName;