util.js

/**
 * --------------------------------------------------------------------------
 * Bootstrap (v4.3.1): util.js
 * Licensed under MIT (https://github.com/twbs/bootstrap/blob/master/LICENSE)
 * --------------------------------------------------------------------------
 */

import EventHandler from './dom/eventHandler'

/**
 * ------------------------------------------------------------------------
 * Private TransitionEnd Helpers
 * ------------------------------------------------------------------------
 */

const TRANSITION_END = 'transitionend'
const MAX_UID = 1000000
const MILLISECONDS_MULTIPLIER = 1000

// Shoutout AngusCroll (https://goo.gl/pxwQGp)
function toType(obj) {
  return {}.toString.call(obj).match(/\s([a-z]+)/i)[1].toLowerCase()
}

const Util = {

  TRANSITION_END: 'bsTransitionEnd',

  getUID(prefix) {
    do {
      // eslint-disable-next-line no-bitwise
      prefix += ~~(Math.random() * MAX_UID) // "~~" acts like a faster Math.floor() here
    } while (document.getElementById(prefix))
    return prefix
  },

  getSelectorFromElement(element) {
    let selector = element.getAttribute('data-target')

    if (!selector || selector === '#') {
      const hrefAttr = element.getAttribute('href')
      selector = hrefAttr && hrefAttr !== '#' ? hrefAttr.trim() : ''
    }

    try {
      return document.querySelector(selector) ? selector : null
    } catch (err) {
      return null
    }
  },

  getTransitionDurationFromElement(element) {
    if (!element) {
      return 0
    }

    // Get transition-duration of the element
    let transitionDuration = element.style.transitionDuration
    let transitionDelay = element.style.transitionDelay

    const floatTransitionDuration = parseFloat(transitionDuration)
    const floatTransitionDelay = parseFloat(transitionDelay)

    // Return 0 if element or transition duration is not found
    if (!floatTransitionDuration && !floatTransitionDelay) {
      return 0
    }

    // If multiple durations are defined, take the first
    transitionDuration = transitionDuration.split(',')[0]
    transitionDelay = transitionDelay.split(',')[0]

    return (parseFloat(transitionDuration) + parseFloat(transitionDelay)) * MILLISECONDS_MULTIPLIER
  },

  reflow(element) {
    return element.offsetHeight
  },

  triggerTransitionEnd(element) {
    EventHandler.trigger(element, Util.TRANSITION_END)
  },

  // TODO: Remove in v5
  supportsTransitionEnd() {
    return Boolean(TRANSITION_END)
  },

  isElement(obj) {
    return (obj[0] || obj).nodeType
  },

  emulateTransitionEnd(element, duration) {
    setTimeout(() => {
      Util.triggerTransitionEnd(element)
    }, duration)
  },

  typeCheckConfig(componentName, config, configTypes) {
    for (const property in configTypes) {
      if (Object.prototype.hasOwnProperty.call(configTypes, property)) {
        const expectedTypes = configTypes[property]
        const value         = config[property]
        const valueType     = value && Util.isElement(value)
          ? 'element' : toType(value)

        if (!new RegExp(expectedTypes).test(valueType)) {
          throw new Error(
            `${componentName.toUpperCase()}: ` +
            `Option "${property}" provided type "${valueType}" ` +
            `but expected type "${expectedTypes}".`)
        }
      }
    }
  },

  findShadowRoot(element) {
    if (!document.documentElement.attachShadow) {
      return null
    }

    // Can find the shadow root otherwise it'll return the document
    if (typeof element.getRootNode === 'function') {
      const root = element.getRootNode()
      return root instanceof ShadowRoot ? root : null
    }

    if (element instanceof ShadowRoot) {
      return element
    }

    // when we don't find a shadow root
    if (!element.parentNode) {
      return null
    }

    return Util.findShadowRoot(element.parentNode)
  }
}

export default Util