class ActiveSupport::NumberHelper::NumberToCurrencyConverter

def absolute_value(number)
  number.respond_to?(:abs) ? number.abs : number.sub(/\A-/, "")
end

def convert
  number = self.number.to_s.strip
  format = options[:format]
  if number.to_f.negative?
    format = options[:negative_format]
    number = absolute_value(number)
  end
  rounded_number = NumberToRoundedConverter.convert(number, options)
  format.gsub("%n", rounded_number).gsub("%u", options[:unit])
end

def i18n_opts
  # Set International negative format if it does not exist
  i18n = i18n_format_options
  i18n[:negative_format] ||= "-#{i18n[:format]}" if i18n[:format]
  i18n
end

def options
  @options ||= begin
    defaults = default_format_options.merge(i18n_opts)
    # Override negative format if format options are given
    defaults[:negative_format] = "-#{opts[:format]}" if opts[:format]
    defaults.merge!(opts)
  end
end