# coding=utf-8
# Copyright 2020 The HuggingFace Datasets Authors and the current dataset script contributor.
#
# Licensed 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.
"""WMT22 African Languages Shared Task"""

import datasets
import csv

_CITATION = ""  # TODO


_DESCRIPTION = ""

_HOMEPAGE = (
    "https://www.statmt.org/wmt22/large-scale-multilingual-translation-task.html"
)

_LICENSE = (
    "https://github.com/facebookresearch/LASER/blob/main/data/wmt22_african/LICENSE"
)


_LANGUAGE_PAIRS = [
    ("afr", "eng"),
    ("afr", "som"),
    ("amh", "eng"),
    ("amh", "fra"),
    ("amh", "nya"),
    ("amh", "orm"),
    ("amh", "sna"),
    ("amh", "som"),
    ("amh", "ssw"),
    ("amh", "swh"),
    ("amh", "tsn"),
    ("amh", "tso"),
    ("amh", "umb"),
    ("amh", "xho"),
    ("amh", "yor"),
    ("amh", "zul"),
    ("eng", "fuv"),
    ("eng", "hau"),
    ("eng", "ibo"),
    ("eng", "kam"),
    ("eng", "kin"),
    ("eng", "lin"),
    ("eng", "lug"),
    ("eng", "luo"),
    ("eng", "nso"),
    ("eng", "nya"),
    ("eng", "orm"),
    ("eng", "sna"),
    ("eng", "som"),
    ("eng", "ssw"),
    ("eng", "swh"),
    ("eng", "tsn"),
    ("eng", "tso"),
    ("eng", "umb"),
    ("eng", "wol"),
    ("eng", "xho"),
    ("eng", "yor"),
    ("eng", "zul"),
    ("fra", "hau"),
    ("fra", "ibo"),
    ("fra", "kam"),
    ("fra", "kin"),
    ("fra", "lin"),
    ("fra", "lug"),
    ("fra", "luo"),
    ("fra", "nso"),
    ("fra", "nya"),
    ("fra", "orm"),
    ("fra", "som"),
    ("fra", "ssw"),
    ("fra", "swh"),
    ("fra", "tsn"),
    ("fra", "tso"),
    ("fra", "umb"),
    ("fra", "wol"),
    ("fra", "xho"),
    ("fra", "zul"),
    ("fuv", "hau"),
    ("fuv", "ibo"),
    ("fuv", "kam"),
    ("fuv", "kin"),
    ("fuv", "lug"),
    ("fuv", "luo"),
    ("fuv", "nso"),
    ("fuv", "nya"),
    ("fuv", "orm"),
    ("fuv", "sna"),
    ("fuv", "som"),
    ("fuv", "ssw"),
    ("fuv", "swh"),
    ("fuv", "tsn"),
    ("fuv", "tso"),
    ("fuv", "umb"),
    ("fuv", "xho"),
    ("fuv", "yor"),
    ("fuv", "zul"),
    ("hau", "ibo"),
    ("hau", "kam"),
    ("hau", "kin"),
    ("hau", "lug"),
    ("hau", "luo"),
    ("hau", "nso"),
    ("hau", "nya"),
    ("hau", "orm"),
    ("hau", "sna"),
    ("hau", "som"),
    ("hau", "ssw"),
    ("hau", "swh"),
    ("hau", "tsn"),
    ("hau", "tso"),
    ("hau", "umb"),
    ("hau", "xho"),
    ("hau", "yor"),
    ("hau", "zul"),
    ("ibo", "kam"),
    ("ibo", "kin"),
    ("ibo", "lug"),
    ("ibo", "luo"),
    ("ibo", "nso"),
    ("ibo", "nya"),
    ("ibo", "orm"),
    ("ibo", "sna"),
    ("ibo", "som"),
    ("ibo", "ssw"),
    ("ibo", "swh"),
    ("ibo", "tsn"),
    ("ibo", "tso"),
    ("ibo", "umb"),
    ("ibo", "xho"),
    ("ibo", "yor"),
    ("ibo", "zul"),
    ("kam", "kin"),
    ("kam", "lug"),
    ("kam", "luo"),
    ("kam", "nso"),
    ("kam", "nya"),
    ("kam", "orm"),
    ("kam", "sna"),
    ("kam", "som"),
    ("kam", "ssw"),
    ("kam", "swh"),
    ("kam", "tsn"),
    ("kam", "tso"),
    ("kam", "umb"),
    ("kam", "xho"),
    ("kam", "yor"),
    ("kam", "zul"),
    ("kin", "lug"),
    ("kin", "luo"),
    ("kin", "nso"),
    ("kin", "nya"),
    ("kin", "orm"),
    ("kin", "sna"),
    ("kin", "som"),
    ("kin", "ssw"),
    ("kin", "swh"),
    ("kin", "tsn"),
    ("kin", "tso"),
    ("kin", "umb"),
    ("kin", "xho"),
    ("kin", "yor"),
    ("kin", "zul"),
    ("lug", "luo"),
    ("lug", "nso"),
    ("lug", "nya"),
    ("lug", "orm"),
    ("lug", "sna"),
    ("lug", "som"),
    ("lug", "ssw"),
    ("lug", "swh"),
    ("lug", "tsn"),
    ("lug", "tso"),
    ("lug", "umb"),
    ("lug", "xho"),
    ("lug", "yor"),
    ("lug", "zul"),
    ("luo", "nso"),
    ("luo", "nya"),
    ("luo", "orm"),
    ("luo", "sna"),
    ("luo", "som"),
    ("luo", "ssw"),
    ("luo", "swh"),
    ("luo", "tsn"),
    ("luo", "tso"),
    ("luo", "umb"),
    ("luo", "xho"),
    ("luo", "yor"),
    ("luo", "zul"),
    ("nso", "nya"),
    ("nso", "orm"),
    ("nso", "sna"),
    ("nso", "som"),
    ("nso", "ssw"),
    ("nso", "swh"),
    ("nso", "tsn"),
    ("nso", "tso"),
    ("nso", "umb"),
    ("nso", "xho"),
    ("nso", "yor"),
    ("nso", "zul"),
    ("nya", "orm"),
    ("nya", "sna"),
    ("nya", "som"),
    ("nya", "ssw"),
    ("nya", "swh"),
    ("nya", "tsn"),
    ("nya", "tso"),
    ("nya", "umb"),
    ("nya", "xho"),
    ("nya", "yor"),
    ("nya", "zul"),
    ("orm", "sna"),
    ("orm", "som"),
    ("orm", "ssw"),
    ("orm", "swh"),
    ("orm", "tsn"),
    ("orm", "tso"),
    ("orm", "umb"),
    ("orm", "xho"),
    ("orm", "yor"),
    ("orm", "zul"),
    ("sna", "som"),
    ("sna", "ssw"),
    ("sna", "swh"),
    ("sna", "tsn"),
    ("sna", "tso"),
    ("sna", "umb"),
    ("sna", "xho"),
    ("sna", "yor"),
    ("sna", "zul"),
    ("som", "ssw"),
    ("som", "swh"),
    ("som", "tsn"),
    ("som", "tso"),
    ("som", "umb"),
    ("som", "wol"),
    ("som", "xho"),
    ("som", "yor"),
    ("som", "zul"),
    ("ssw", "swh"),
    ("ssw", "tsn"),
    ("ssw", "tso"),
    ("ssw", "umb"),
    ("ssw", "xho"),
    ("ssw", "yor"),
    ("ssw", "zul"),
    ("swh", "tsn"),
    ("swh", "tso"),
    ("swh", "umb"),
    ("swh", "xho"),
    ("swh", "yor"),
    ("swh", "zul"),
    ("tsn", "tso"),
    ("tsn", "umb"),
    ("tsn", "xho"),
    ("tsn", "yor"),
    ("tsn", "zul"),
    ("tso", "umb"),
    ("tso", "xho"),
    ("tso", "yor"),
    ("tso", "zul"),
    ("umb", "xho"),
    ("umb", "yor"),
    ("umb", "zul"),
    ("xho", "yor"),
    ("xho", "zul"),
    ("yor", "zul"),
]

_URL_BASE = "https://huggingface.co/datasets/allenai/wmt22_african/resolve/main/"

_URLs = {
    f"{src_lg}-{trg_lg}": f"{_URL_BASE}wmt22_african_{src_lg}-{trg_lg}.gz"
    for src_lg, trg_lg in _LANGUAGE_PAIRS
}


class Wmt22AfricanTaskConfig(datasets.BuilderConfig):
    """BuilderConfig for WMT22 African Shared Task."""

    def __init__(self, src_lg, tgt_lg, **kwargs):
        super(Wmt22AfricanTaskConfig, self).__init__(**kwargs)
        self.src_lg = src_lg
        self.tgt_lg = tgt_lg


class Wmt22African(datasets.GeneratorBasedBuilder):
    """WMT African Languages Shared Task."""

    BUILDER_CONFIGS = [
        Wmt22AfricanTaskConfig(
            name=f"{src_lg}-{tgt_lg}",
            version=datasets.Version("1.0.0"),
            description=f"WMT 2022 African Languages: {src_lg} - {tgt_lg}",
            src_lg=src_lg,
            tgt_lg=tgt_lg,
        )
        for (src_lg, tgt_lg) in _LANGUAGE_PAIRS
    ]
    BUILDER_CONFIG_CLASS = Wmt22AfricanTaskConfig

    def _info(self):
        # define feature types
        features = datasets.Features(
            {
                "translation": datasets.Translation(
                    languages=(self.config.src_lg, self.config.tgt_lg)
                ),
                "laser_score": datasets.Value("float32"),
                "source_sentence_lid": datasets.Value("float32"),
                "target_sentence_lid": datasets.Value("float32"),
            }
        )

        return datasets.DatasetInfo(
            description=_DESCRIPTION,
            features=features,
            supervised_keys=None,
            homepage=_HOMEPAGE,
            license=_LICENSE,
            citation=_CITATION,
        )

    def _split_generators(self, dl_manager):
        """Returns SplitGenerators."""
        pair = f"{self.config.src_lg}-{self.config.tgt_lg}"  # string identifier for language pair
        url = _URLs[pair]  # url for download of pair-specific file
        data_file = dl_manager.download_and_extract(
            url
        )  # extract downloaded data and store path in data_file

        return [
            datasets.SplitGenerator(
                name=datasets.Split.TRAIN,
                gen_kwargs={
                    "filepath": data_file,
                    "source_lg": self.config.src_lg,
                    "target_lg": self.config.tgt_lg,
                },
            )
        ]

    def _generate_examples(self, filepath, source_lg, target_lg):
        with open(filepath, encoding="utf-8") as f:
            # reader = csv.reader(f, delimiter="\t")
            for id_, example in enumerate(f):
                try:
                    datarow = example.split("\t")
                    row = {}
                    row["translation"] = {
                        source_lg: datarow[0],
                        target_lg: datarow[1],
                    }  # create translation json
                    scores = datarow[2].split(" ")
                    row["laser_score"] = float(scores[0])
                    row["source_sentence_lid"] = float(scores[1])
                    row["target_sentence_lid"] = float(scores[2])
                    row = {
                        k: None if not v else v for k, v in row.items()
                    }  # replace empty values
                except:
                    print(datarow)
                    raise
                yield id_, row


# to test the script, go to the root folder of the repo (wmt22_african) and run:
# datasets-cli test wmt22_african --save_infos --all_configs