#
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements.  See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License.  You may obtain a copy of the License at
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#    http://www.apache.org/licenses/LICENSE-2.0
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# distributed under the License is distributed on an "AS IS" BASIS,
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"""Utilities for the Nexmark suite.

The Nexmark suite is a series of queries (streaming pipelines) performed
on a simulation of auction events. This util includes:

  - A Command class used to terminate the streaming jobs
    launched in nexmark_launcher.py by the DirectRunner.
  - A ParseEventFn DoFn to parse events received from PubSub.

Usage:

To run a process for a certain duration, define in the code:
  command = Command(process_to_terminate, args)
  command.run(timeout=duration)

"""

from __future__ import absolute_import
from __future__ import print_function

import logging
import threading

import apache_beam as beam
from apache_beam.testing.benchmarks.nexmark.models import nexmark_model

_LOGGER = logging.getLogger()


class Command(object):
  def __init__(self, cmd, args):
    self.cmd = cmd
    self.args = args

  def run(self, timeout):
    def thread_target():
      logging.debug('Starting thread for %d seconds: %s',
                    timeout, self.cmd.__name__)

      self.cmd(*self.args)
      _LOGGER.info('%d seconds elapsed. Thread (%s) finished.',
                   timeout, self.cmd.__name__)

    thread = threading.Thread(target=thread_target, name='Thread-timeout')
    thread.daemon = True
    thread.start()
    thread.join(timeout)


class ParseEventFn(beam.DoFn):
  """Parses the raw event info into a Python objects.

  Each event line has the following format:

    person: <id starting with 'p'>,name,email,credit_card,city, \
                          state,timestamp,extra
    auction: <id starting with 'a'>,item_name, description,initial_bid, \
                          reserve_price,timestamp,expires,seller,category,extra
    bid: <auction starting with 'b'>,bidder,price,timestamp,extra

  For example:

    'p12345,maria,maria@maria.com,1234-5678-9012-3456, \
                                        sunnyvale,CA,1528098831536'
    'a12345,car67,2012 hyundai elantra,15000,20000, \
                                        1528098831536,20180630,maria,vehicle'
    'b12345,maria,20000,1528098831536'
  """

  def process(self, elem):
    model_dict = {
        'p': nexmark_model.Person,
        'a': nexmark_model.Auction,
        'b': nexmark_model.Bid,
    }
    row = elem.split(',')
    model = model_dict.get(elem[0])
    if not model:
      raise ValueError('Invalid event: %s.' % row)

    event = model(*row)
    logging.debug('Parsed event: %s', event)
    yield event


def display(elm):
  logging.debug(elm)
  return elm
