class Mail::CommonDateField

def self.normalize_datetime(string)
  if Utilities.blank?(string)
    datetime = ::DateTime.now
  else
    stripped = string.to_s.gsub(/\(.*?\)/, '').squeeze(' ')
    begin
      datetime = ::DateTime.parse(stripped)
    rescue ArgumentError => e
      raise unless 'invalid date' == e.message
    end
  end
  if datetime
    datetime.strftime('%a, %d %b %Y %H:%M:%S %z')
  else
    string
  end
end