Split html string in parts by tag

split-text-by-tag.js

/**
 * Splits a string in half by tag name
 * i.e. '<p>' or 'p'
 * returns array of 2 strings
 *
*/
export const splitTextByTag = (text, tag) => {
  let closingTag = '';
  // clean text from line breaks
  let cleanText = text.replace(/\r?\n|\r/g, '');
  let resultArray = [];

  // Add openning bracket if not specified
  if (tag.indexOf('<') === -1) {
    closingTag = '<';
  }
  // Add closing slash if not specified
  if (tag.indexOf('/') === -1) {
    // case when specifying tag without slash i.e. <p>
    if (tag.indexOf('<') !== -1) {
      closingTag =  ['</', tag.slice(1)].join('');
    } else {
      closingTag += '/';
    }
  }
  // Add closing bracket if not specified
  if (tag.indexOf('>') === -1) {
    closingTag += tag + '>';
  }

  // Split by closing tag
  let splittedArray = cleanText && cleanText.split(closingTag);
  // Remove empty elements
  splittedArray = splittedArray.filter((text) => text.length)
  // add back tag removed by split
  splittedArray = splittedArray.map((text) => text + closingTag);
  // get first block of text
  resultArray[0] = splittedArray[0]
  // join the rest if any
  if (splittedArray.length > 1) {
    splittedArray.shift()
    resultArray[1] = splittedArray.join('')
  }

  return resultArray;
}