#!/usr/bin/env ruby -Ku

Encoding.default_external = "UTF-8" # wake up, smell the coffee

require 'kramdown'
require 'kramdown-parser-gfm'

if ARGV[0] == '-k'              # kramdown
  MARKDOWN_BR = "\\\\\n"
  ARGV.shift
end

if ARGV[0] == '-c'              # commonmark
  MARKDOWN_BR = "\\\n"
  ARGV.shift
end

if ARGV[0] == '-b'              # universal HTML
  MARKDOWN_BR = "<br/>\n"
  ARGV.shift
end

MARKDOWN_BR ||= "  \n"          # original Gruber

module Kramdown

  module Converter

    # Converts an element tree to the kramdown format.
    class Kramdown < Base

      # Argh
      def convert_br(_el, _opts)
        MARKDOWN_BR
      end
    end
  end
end

puts Kramdown::Document.new(ARGF.read, input: 'GFM', gfm_quirks: 'paragraph_end').to_kramdown
