class TOML::Dumper

def initialize(hash)
  @toml_str = ''
  visit(hash, '')
end

def to_toml(obj)
  case
  when obj.is_a?(Time)
    obj.strftime('%Y-%m-%dT%H:%M:%SZ')
  else
    obj.inspect
  end
end

def visit(hash, prefix)
  nested_pairs = []
  simple_pairs = []
  hash.keys.sort.each do |key|
    val = hash[key]
    (val.is_a?(Hash) ? nested_pairs : simple_pairs) << [key, val]
  end
  @toml_str += "[#{prefix}]\n" unless prefix.empty? || simple_pairs.empty?
  # First add simple pairs, under the prefix
  simple_pairs.each do |key, val|
    @toml_str << "#{key.to_s} = #{to_toml(val)}\n"
  end
  nested_pairs.each do |key, val|
    visit(val, prefix.empty? ? key.to_s : [prefix, key].join('.'))
  end
end