Get lines from dom element

getTextLinesFromElement.js

function getTextLinesFromElement(target) {
  const originalHtml = target.innerHTML;
  const lines = [];
  let currentLine = [];
  let prevWordTop;
  
  target.innerHTML = target.textContent.split(' ').map(w => `<span>${w}</span>`).join(' ');
  Array.from(target.querySelectorAll('span')).forEach((span, i , spans) => {
    const text = span.textContent;
    if (text === '') {
      return;
    }
    
    const top = span.offsetTop;
    
    if (typeof prevWordTop === 'undefined') {
      prevWordTop = top;
    }
    
    if (prevWordTop !== top) {
      lines.push(currentLine.join(' '));
      currentLine = [];
      prevWordTop = top;
    }
    
    currentLine.push(text);
  });
  
  lines.push(currentLine.join(' '));
  target.innerHTML = originalHtml;
  
  return lines;
}