#!/usr/bin/python
# Copyright 2016 The Chromium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import randomizer
import utils.file_util as file_util


class HourRandomizer:
  """ A Randomizer that extracts hour from |Entry| and applies randomized
  response algorithms to hour-of-the-day field to emit noised reports.
  Additionally, it uses user_id from |Entry| to setup the secret in the RAPPOR
  encoder. (The secret is irrelevant for the purposes of this demo.)
  """

  def randomize(self, entries):
    """ A Randomizer that extracts hour from |Entry| and applies randomized
    response algorithms to it to emit noised reports.

    This function does not return anything but it writes a file
    into the "r_to_s" output directory containing the randomizer output.

    Args:
      entries {list of Entry}: The entries to be randomized.
    """
    randomizer.randomizeUsingRappor(entries,
        [(3, # hour index in |Entry|
         False, # no bloom filters
         file_util.RAPPOR_HOUR_CONFIG # rappor config file name
        )],
        file_util.HOUR_RANDOMIZER_OUTPUT_FILE_NAME,
        );