import csv

import datasets

_DESCRIPTION = "Swedish school lunches."

_TRAIN_DOWNLOAD_URL = "./meals.csv"

labels = ["FOOD", "NO", "ANY", "SIDE", "MESSAGE", "GENERIC"]


class Skolmat(datasets.GeneratorBasedBuilder):
    def _info(self):
        return datasets.DatasetInfo(
            description=_DESCRIPTION,
            features=datasets.Features(
                {
                    "meal": datasets.Value("string"),
                    "label": datasets.features.ClassLabel(names=labels),
                }
            ),
        )

    def _split_generators(self, dl_manager):
        train_path = dl_manager.download_and_extract(_TRAIN_DOWNLOAD_URL)
        return [
            datasets.SplitGenerator(
                name=datasets.Split.TRAIN, gen_kwargs={"filepath": train_path}
            ),
        ]

    def _generate_examples(self, filepath):
        with open(filepath, encoding="utf8") as csv_file:
            reader = csv.reader(csv_file)
            next(reader, None)  # skip the headers
            for i, row in enumerate(reader):
                (meal, label) = row
                yield i, {
                    "meal": meal,
                    "label": labels.index(label),
                }