import json
import datasets

class TeleData(datasets.GeneratorBasedBuilder):
    """Tele-Data dataset with multiple subsets: arxiv, standard, web, and wiki"""

    BUILDER_CONFIGS = [
        datasets.BuilderConfig(name="arxiv", version=datasets.Version("1.0.0"), description="ArXiv data"),
        datasets.BuilderConfig(name="standard", version=datasets.Version("1.0.0"), description="Standard data"),
        datasets.BuilderConfig(name="web", version=datasets.Version("1.0.0"), description="Web data"),
        datasets.BuilderConfig(name="wiki", version=datasets.Version("1.0.0"), description="Wiki data"),
        datasets.BuilderConfig(name="full", version=datasets.Version("1.0.0"), description="Full dataset"),
    ]

    DEFAULT_CONFIG_NAME = "full"

    def _info(self):
        features = datasets.Features({
            "id": datasets.Value("string"),
            "category": datasets.Value("string"),
            "content": datasets.Value("string"),
            "metadata": datasets.Value("string"), 
        })
        return datasets.DatasetInfo(features=features)

    def _split_generators(self, dl_manager):
        if self.config.name == "full":
            urls = [f"{name}/{name}.jsonl" for name in ["arxiv", "standard", "web", "wiki"]]
        else:
            urls = [f"{self.config.name}/{self.config.name}.jsonl"]

        data_files = dl_manager.download_and_extract(urls)
        
        return [
            datasets.SplitGenerator(
                name=datasets.Split.TRAIN,
                gen_kwargs={"filepaths": data_files if isinstance(data_files, list) else [data_files]},
            )
        ]

    def _generate_examples(self, filepaths):
        for filepath in filepaths:
            with open(filepath, "r", encoding="utf-8") as f:
                for id_, line in enumerate(f):
                    data = json.loads(line)
                    yield id_, {
                        "id": data["id"],
                        "category": data["category"],
                        "content": data["content"],
                        "metadata": json.dumps(data["metadata"]), 
                    }