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#   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
#
#       http://www.apache.org/licenses/LICENSE-2.0
#
#   Unless required by applicable law or agreed to in writing, software
#   distributed under the License is distributed on an "AS IS" BASIS,
#   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
#   See the License for the specific language governing permissions and
#   limitations under the License.

# beam-playground:
#   name: WindowingSolution
#   description: Windowing motivating challenge solution.
#   multifile: false
#   context_line: 65
#   categories:
#     - Quickstart
#   complexity: ADVANCED
#   tags:
#     - hellobeam

import apache_beam as beam
from apache_beam import window

# Output PCollection
class Output(beam.PTransform):
    class _OutputFn(beam.DoFn):
        def __init__(self, prefix=''):
            super().__init__()
            self.prefix = prefix

        def process(self, element):
            print(self.prefix+str(element))

    def __init__(self, label=None,prefix=''):
        super().__init__(label)
        self.prefix = prefix

    def expand(self, input):
        input | beam.ParDo(self._OutputFn(self.prefix))

class ExtractTaxiRideCostFn(beam.DoFn):

    def process(self, element):
        line = element.split(',')
        return tryParseTaxiRideCost(line,16)


def tryParseTaxiRideCost(line,index):
    if(len(line) > index):
      try:
        yield float(line[index])
      except:
        yield float(0)
    else:
        yield float(0)


with beam.Pipeline() as p:

  input = (p | 'Log lines' >> beam.io.ReadFromText('gs://apache-beam-samples/nyc_taxi/misc/sample1000.csv')
  | beam.ParDo(ExtractTaxiRideCostFn()))

  (input | 'window' >>  beam.WindowInto(window.SlidingWindows(10, 5))
  | 'Sum above cost' >> beam.CombineGlobally(max).without_defaults()
  | 'Log above cost' >> Output())

