#!/usr/bin/env ruby

fix = ARGV.shift if ARGV.first == "--fix"
files = Array(ARGV.shift || Dir.glob("./**/*.md"))

files.each do |file|
  content = File.read(file)

  refs = content.scan(/^\[\d+\]:/)

  unless refs == refs.uniq
    warn "Error in #{file}: duplicate refs detected"
    exit 1
  end

  idx = 0
  code_block = false
  refs = {}

  updated = content.gsub(/\[\d+\]|```|`/) do |token|
    case token
    when "```", "`"
      code_block = !code_block
      token
    else
      if code_block
        token
      else
        refs[token] ||= "[$$#{idx += 1}]"
      end
    end
  end

  updated.gsub!("$$", "")

  if fix
    File.write(file, updated)
  elsif content != updated
    warn "Links in #{file} are not in order"
    exit 1
  end
end