from dataclasses import dataclass

import datasets
from pytorch_ie.annotations import LabeledSpan
from pytorch_ie.core import AnnotationList, annotation_field
from pytorch_ie.documents import TextDocument, TextDocumentWithLabeledSpans
from pytorch_ie.utils.span import tokens_and_tags_to_text_and_labeled_spans

from pie_datasets import GeneratorBasedBuilder


@dataclass
class CoNLL2003Document(TextDocument):
    entities: AnnotationList[LabeledSpan] = annotation_field(target="text")


class Conll2003(GeneratorBasedBuilder):
    DOCUMENT_TYPE = CoNLL2003Document

    BASE_DATASET_PATH = "conll2003"
    BASE_DATASET_REVISION = "01ad4ad271976c5258b9ed9b910469a806ff3288"

    BUILDER_CONFIGS = [
        datasets.BuilderConfig(
            name="conll2003", version=datasets.Version("1.0.0"), description="CoNLL2003 dataset"
        ),
    ]

    DOCUMENT_CONVERTERS = {
        TextDocumentWithLabeledSpans: {
            # just rename the layer
            "entities": "labeled_spans",
        }
    }

    def _generate_document_kwargs(self, dataset):
        return {"int_to_str": dataset.features["ner_tags"].feature.int2str}

    def _generate_document(self, example, int_to_str):
        doc_id = example["id"]
        tokens = example["tokens"]
        ner_tags = [int_to_str(tag) for tag in example["ner_tags"]]

        text, ner_spans = tokens_and_tags_to_text_and_labeled_spans(tokens=tokens, tags=ner_tags)

        document = CoNLL2003Document(text=text, id=doc_id)

        for span in sorted(ner_spans, key=lambda span: span.start):
            document.entities.append(span)

        return document