Ruby On Rails code used to divide a html text with <p> tags. It is just a piece of code, you can copy and paste in a helper.

divide_text_helper.rb

# After some research on how to divide a text with html tags my final solution is here
# this should work with strings.
# If you found a better solution, please let me know.

def divided_text(text)
  # we have the start index of </p>, so we need do +3 to get the end
  middle_index = middle_paragraph_index(text)+3
  first_text = text[0..middle_index]
  # and here we have the '>' so we need do +1
  second_text = text[middle_index+1..-1]

  text_list = [first_text, second_text]
end

private
  # thanks to https://stackoverflow.com/questions/3520208/get-index-of-string-scan-results-in-ruby
  def middle_paragraph_index(text)
    # count the paragraphs
    paragraphs_count = text.scan(/(?=<p>)/).count
    half_paragraphs = paragraphs_count/2 -1

    res = []
    text.scan(/<\/p>/) do |c|
      res << [c, Regexp.last_match.offset(0).first]
    end
    # res[] will have all </p> with their index
    # we just want the index of the middle.
    res[half_paragraphs][1]
  end