from datasets import Features, Sequence, Value
features = Features({
    "id": Value("string"),
    "asked_at": Value("string"),
    "author_name": Value("string"),
    "author_rep": Value("string"),
    "score": Value("int32"),
    "title": Value("string"),
    "tags": Sequence(Value("string")),
    "body": Value("string"),
    "comments": Sequence({
        "id": Value("string"),
        "body": Value("string"),
        "at": Value("string"),
        "score": Value("string"),
        "author": Value("string"),
        "author_rep": Value("string"),
    }),
    "answers": Sequence({
        "id": Value("string"),
        "body": Value("string"),
        "score": Value("int32"),
        "ts": Value("string"),
        "author": Value("string"),
        "author_rep": Value("string"),
        "accepted": Value("bool"),
        "comments": Sequence({
            "id": Value("string"),
            "body": Value("string"),
            "at": Value("string"),
            "score": Value("string"),
            "author": Value("string"),
            "author_rep": Value("string"),
        }),
    }),
})

# coding=utf-8
"""The dataset is a collection of Question and Answer automatically extracted from Stack Exchange community network."""


import csv
import json
import os
import zstandard
import io

import datasets

# TODO: Add description of the dataset here
# You can copy an official description
_DESCRIPTION = """\
This new dataset is designed to solve this great NLP task and is crafted with a lot of care.
"""

# TODO: Add a link to an official homepage for the dataset here
_HOMEPAGE = "https://huggingface.co/datasets/nurik040404/mse"
_URL = 'dataset.jsonl.zst'

# TODO: Name of the dataset usually match the script name with CamelCase instead of snake_case
class StackExchange(datasets.GeneratorBasedBuilder):
    """The dataset is a collection of Question and Answer automatically extracted from match Stack Exchange community."""

    VERSION = datasets.Version("1.0.0")

    BUILDER_CONFIG = datasets.BuilderConfig(name=_URL)


    def _info(self):
        return datasets.DatasetInfo(
            # This is the description that will appear on the datasets page.
            description=_DESCRIPTION,
            # This defines the different columns of the dataset and their types
            features=features,  # Here we define them above because they are different between the two configurations
            # If there's a common (input, target) tuple from the features,
            # specify them here. They'll be used if as_supervised=True in
            # builder.as_dataset.
            supervised_keys=None,
            # Homepage of the dataset for documentation
            homepage=_HOMEPAGE,
            # License for the dataset if available
            # license=_LICENSE,
            # Citation for the dataset
            # citation=_CITATION,
        )

    def _split_generators(self, dl_manager):
        """Returns SplitGenerators."""
        # TODO: This method is tasked with downloading/extracting the data and defining the splits depending on the configuration
        # If several configurations are possible (listed in BUILDER_CONFIGS), the configuration selected by the user is in self.config.name

        # dl_manager is a datasets.download.DownloadManager that can be used to download and extract URLs
        # It can accept any type or nested list/dict and will give back the same structure with the url replaced with path to local files.
        # By default the archives will be extracted and a path to a cached folder where they are extracted is returned instead of the archive
        data_file = dl_manager.download(_URL)
        return [
            datasets.SplitGenerator(
                name=datasets.Split.TRAIN,
                # These kwargs will be passed to _generate_examples
                gen_kwargs={
                    "filepath": data_file,
                },
            )
        ]

    def _generate_examples(
        self, filepath  # method parameters are unpacked from `gen_kwargs` as given in `_split_generators`
    ):
        """ Yields examples as (key, example) tuples. """
        # This method handles input defined in _split_generators to yield (key, example) tuples from the dataset.
        # The `key` is here for legacy reason (tfds) and is not important in itself.

        with open(filepath, 'rb') as f:
            dctx = zstandard.ZstdDecompressor()
            with dctx.stream_reader(f) as ds:
                with io.TextIOWrapper(ds) as s:
                    i = 0
                    while s.readable():
                        yield i, json.loads(s.readline())
                        i += 1