inline_markdown_footnotes.rb

#!/usr/bin/env ruby
# frozen_string_literal: false

# bcdav 2021
# inspired by https://github.com/ltrgoddard/inliner

Encoding.default_external = Encoding::UTF_8

class String
  def inline_mmd
    text = self
    counter = 0
    pandoc_mode = false
    loop do
      counter += 1
      cite = "[^#{counter}]"
      ref = "[^#{counter}]:"
      ref_start = text.index(ref)
      break if ref_start.nil?
  
      next_ref = "[^#{counter + 1}]:"
      ref_end = text.index(next_ref).nil? ? -1 : text.index(next_ref) - 2
      offset = counter.to_s.length + 5
      note = pandoc_mode ? "^[#{text[ref_start + offset..ref_end].strip}]" : "[^#{text[ref_start + offset..ref_end].strip}]"
  
      text.gsub!(cite, note)
    end
  
    if counter >= 1
      text = pandoc_mode ? text.gsub(/\n\s*\^\[/, "\n^[") : text.gsub(/\n\s*\[\^/, "\n[^")
      cut_point = pandoc_mode ? text.index("\n^") : text.index("\n[^")
      text = text[0, cut_point]
      # puts "#{counter -= 1} notes replaced."
    end
    puts text
  end

  def inline_pandoc
  text = self    
  counter = 0
  pandoc_mode = true
  loop do
    counter += 1
    cite = "[^#{counter}]"
    ref = "[^#{counter}]:"
    ref_start = text.index(ref)
    break if ref_start.nil?

    next_ref = "[^#{counter + 1}]:"
    ref_end = text.index(next_ref).nil? ? -1 : text.index(next_ref) - 2
    offset = counter.to_s.length + 5
    note = pandoc_mode ? "^[#{text[ref_start + offset..ref_end].strip}]" : "[^#{text[ref_start + offset..ref_end].strip}]"

    text.gsub!(cite, note)
  end

  if counter >= 1
    text = pandoc_mode ? text.gsub(/\n\s*\^\[/, "\n^[") : text.gsub(/\n\s*\[\^/, "\n[^")
    cut_point = pandoc_mode ? text.index("\n^") : text.index("\n[^")
    text = text[0, cut_point]
    # puts "#{counter -= 1} notes replaced."
  end
  puts text
  end
end


str = <<EOS
Lorem ipsum dolor sit amet[^1], consectetur adipisicing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua. Ut enim ad minim veniam, quis nostrud exercitation ullamco laboris nisi ut aliquip ex ea commodo consequat.

[^1]: Duis aute irure dolor in reprehenderit in voluptate velit esse cillum dolore eu fugiat nulla pariatur. Excepteur sint occaecat cupidatat non proident, sunt in culpa qui officia deserunt mollit anim id est laborum.
EOS

puts str.inline_pandoc
# puts str.inline_mmd