module Bundler::YAMLSerializer

def dump(hash)
  yaml = String.new("---")
  yaml << dump_hash(hash)
end

def dump_hash(hash)
  yaml = String.new("\n")
  hash.each do |k, v|
    yaml << k << ":"
    if v.is_a?(Hash)
      yaml << dump_hash(v).gsub(/^(?!$)/, "  ") # indent all non-empty lines
    elsif v.is_a?(Array) # Expected to be array of strings
      if v.empty?
        yaml << " []\n"
      else
        yaml << "\n- " << v.map {|s| s.to_s.gsub(/\s+/, " ").inspect }.join("\n- ") << "\n"
      end
    else
      yaml << " " << v.to_s.gsub(/\s+/, " ").inspect << "\n"
    end
  end
  yaml
end

def load(str)
  res = {}
  stack = [res]
  last_hash = nil
  last_empty_key = nil
  str.split(/\r?\n/) do |line|
    if match = HASH_REGEX.match(line)
      indent, key, quote, val = match.captures
      val = strip_comment(val)
      depth = indent.size / 2
      if quote.empty? && val.empty?
        new_hash = {}
        stack[depth][key] = new_hash
        stack[depth + 1] = new_hash
        last_empty_key = key
        last_hash = stack[depth]
      else
        val = [] if val == "[]" # empty array
        stack[depth][key] = val
      end
    elsif match = ARRAY_REGEX.match(line)
      _, val = match.captures
      val = strip_comment(val)
      last_hash[last_empty_key] = [] unless last_hash[last_empty_key].is_a?(Array)
      last_hash[last_empty_key].push(val)
    end
  end
  res
end

def strip_comment(val)
  if val.include?("#") && !val.start_with?("#")
    val.split("#", 2).first.strip
  else
    val
  end
end