# coding=utf-8
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# Lint as: python3
"""WMT15: Translate dataset."""

from __future__ import absolute_import
from __future__ import division
from __future__ import print_function

import tensorflow_datasets.public_api as tfds
from tensorflow_datasets.translate import wmt

_URL = "http://www.statmt.org/wmt15/translation-task.html"
_CITATION = """
@InProceedings{bojar-EtAl:2015:WMT,
  author    = {Bojar, Ond\v{r}ej  and  Chatterjee, Rajen  and  Federmann, Christian  and  Haddow, Barry  and  Huck, Matthias  and  Hokamp, Chris  and  Koehn, Philipp  and  Logacheva, Varvara  and  Monz, Christof  and  Negri, Matteo  and  Post, Matt  and  Scarton, Carolina  and  Specia, Lucia  and  Turchi, Marco},
  title     = {Findings of the 2015 Workshop on Statistical Machine Translation},
  booktitle = {Proceedings of the Tenth Workshop on Statistical Machine Translation},
  month     = {September},
  year      = {2015},
  address   = {Lisbon, Portugal},
  publisher = {Association for Computational Linguistics},
  pages     = {1--46},
  url       = {http://aclweb.org/anthology/W15-3001}
}
"""

_LANGUAGE_PAIRS = [
    (lang, "en") for lang in ["cs", "de", "fi", "fr", "ru"]
]


class Wmt15Translate(wmt.WmtTranslate):
  """WMT 15 translation datasets for all {xx, "en"} language pairs."""

  BUILDER_CONFIGS = [
      wmt.WmtConfig(  # pylint:disable=g-complex-comprehension
          description="WMT 2015 %s-%s translation task dataset." % (l1, l2),
          url=_URL,
          citation=_CITATION,
          language_pair=(l1, l2),
          version=tfds.core.Version("1.0.0"),
      ) for l1, l2 in _LANGUAGE_PAIRS
  ] + [
      wmt.WmtConfig(  # pylint:disable=g-complex-comprehension
          description=(
              "WMT 2015 %s-%s translation task dataset with subword encoding."
              % (l1, l2)),
          url=_URL,
          citation=_CITATION,
          language_pair=(l1, l2),
          text_encoder_config=tfds.features.text.TextEncoderConfig(
              encoder_cls=tfds.features.text.SubwordTextEncoder,
              name="subwords8k",
              vocab_size=2**13),
          version=tfds.core.Version("1.0.0"),
          )
      for l1, l2 in _LANGUAGE_PAIRS
  ]

  @property
  def _subsets(self):
    return {
        tfds.Split.TRAIN: [
            "europarl_v7", "europarl_v8_16", "commoncrawl", "multiun",
            "newscommentary_v10", "gigafren", "czeng_10", "yandexcorpus",
            "wikiheadlines_fi", "wikiheadlines_ru"],
        tfds.Split.VALIDATION: [
            "newsdev2015", "newsdiscussdev2015", "newstest2014"
        ],
        tfds.Split.TEST: [
            "newstest2015", "newsdiscusstest2015",
        ]
    }