module.exports = function nl2br(str, isXhtml) {
  //  discuss at: https://locutus.io/php/nl2br/
  // original by: Kevin van Zonneveld (https://kvz.io)
  // improved by: Philip Peterson
  // improved by: Onno Marsman (https://twitter.com/onnomarsman)
  // improved by: Atli Þór
  // improved by: Brett Zamir (https://brett-zamir.me)
  // improved by: Maximusya
  // bugfixed by: Onno Marsman (https://twitter.com/onnomarsman)
  // bugfixed by: Kevin van Zonneveld (https://kvz.io)
  // bugfixed by: Reynier de la Rosa (https://scriptinside.blogspot.com.es/)
  //    input by: Brett Zamir (https://brett-zamir.me)
  //   example 1: nl2br('Kevin\nvan\nZonneveld')
  //   returns 1: 'Kevin<br />\nvan<br />\nZonneveld'
  //   example 2: nl2br("\nOne\nTwo\n\nThree\n", false)
  //   returns 2: '<br>\nOne<br>\nTwo<br>\n<br>\nThree<br>\n'
  //   example 3: nl2br("\nOne\nTwo\n\nThree\n", true)
  //   returns 3: '<br />\nOne<br />\nTwo<br />\n<br />\nThree<br />\n'
  //   example 4: nl2br(null)
  //   returns 4: ''

  // Some latest browsers when str is null return and unexpected null value
  if (typeof str === 'undefined' || str === null) {
    return ''
  }

  // Adjust comment to avoid issue on locutus.io display
  const breakTag = isXhtml || typeof isXhtml === 'undefined' ? '<br ' + '/>' : '<br>'

  return (str + '').replace(/(\r\n|\n\r|\r|\n)/g, breakTag + '$1')
}