class Fluent::TimeFormatter

def initialize(format = nil, localtime = true, timezone = nil)
  @tc1 = 0
  @tc1_str = nil
  @tc2 = 0
  @tc2_str = nil
  strftime = format && (Strftime.new(format) rescue nil)
  if format && format =~ /(^|[^%])(%%)*%L|(^|[^%])(%%)*%\d*N/
    define_singleton_method(:format, method(:format_with_subsec))
    define_singleton_method(:call, method(:format_with_subsec))
  else
    define_singleton_method(:format, method(:format_without_subsec))
    define_singleton_method(:call, method(:format_without_subsec))
  end
  formatter = Fluent::Timezone.formatter(timezone, strftime ? strftime : format)
  @format_nocache = case
                    when formatter             then formatter
                    when strftime && localtime then ->(time){ strftime.exec(Time.at(time)) }
                    when format && localtime   then ->(time){ Time.at(time).strftime(format) }
                    when strftime              then ->(time){ strftime.exec(Time.at(time).utc) }
                    when format                then ->(time){ Time.at(time).utc.strftime(format) }
                    when localtime             then ->(time){ Time.at(time).iso8601 }
                    else                            ->(time){ Time.at(time).utc.iso8601 }
                    end
end