import glob
import os
import yaml
import datasets
from PIL import Image


_VERSION = "2024-06-04"
_URL = f"https://github.com/DEFI-COLaF/LADaS/archive/refs/tags/{_VERSION}.tar.gz"
_HOMEPAGE = "https://github.com/DEFI-COLaF/LADaS"
_LICENSE = "CC BY 4.0"
_CITATION = """\
@misc{Clerice_Layout_Analysis_Dataset,
    author = {Clérice, Thibault and Janès, Juliette and Scheithauer, Hugo and Bénière, Sarah and Langlais, Pierre-Carl and Romary, Laurent and Sagot, Benoit and Bougrelle, Roxane},
    title = {{Layout Analysis Dataset with SegmOnto (LADaS)}},
    url = {https://github.com/DEFI-COLaF/LADaS}
}
"""

_CATEGORIES = ['AdvertisementZone', 'DigitizationArtefactZone', 'DropCapitalZone', 'FigureZone', 'FigureZone-FigDesc', 'FigureZone-Head', 'GraphicZone', 'GraphicZone-Decoration', 'GraphicZone-FigDesc', 'GraphicZone-Head', 'GraphicZone-Maths', 'GraphicZone-Part', 'GraphicZone-TextualContent', 'MainZone-Date', 'MainZone-Entry', 'MainZone-Entry-Continued', 'MainZone-Form', 'MainZone-Head', 'MainZone-Lg', 'MainZone-Lg-Continued', 'MainZone-List', 'MainZone-List-Continued', 'MainZone-Other', 'MainZone-P', 'MainZone-P-Continued', 'MainZone-Signature', 'MainZone-Sp', 'MainZone-Sp-Continued', 'MarginTextZone-ManuscriptAddendum', 'MarginTextZone-Notes', 'MarginTextZone-Notes-Continued', 'NumberingZone', 'PageTitleZone', 'PageTitleZone-Index', 'QuireMarkZone', 'RunningTitleZone', 'StampZone', 'StampZone-Sticker', 'TableZone', 'TableZone-Continued', 'TableZone-Head']


class LadasConfig(datasets.BuilderConfig):
    """Builder Config for LADaS"""
    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)


class LadasDataset(datasets.GeneratorBasedBuilder):
    VERSION = datasets.Version(_VERSION.replace("-", "."))
    BUILDER_CONFIGS = [
        LadasConfig(
            name="full",
            description="Full version of the dataset"
        )
    ]

    def _info(self) -> datasets.DatasetInfo:
        features = datasets.Features({
            "image_path": datasets.Value("string"),
            "image": datasets.Image(),
            # "width": datasets.Value("int32"),
            # "height": datasets.Value("int32"),
            "objects": datasets.Sequence(
                {
                    "bbox": datasets.Sequence(datasets.Value("float32"), length=4),
                    "category": datasets.ClassLabel(names=_CATEGORIES),
                }
            )
        })
        return datasets.DatasetInfo(
            features=features,
            homepage=_HOMEPAGE,
            citation=_CITATION,
            license=_LICENSE
        )

    def _split_generators(self, dl_manager):
        urls_to_download = _URL
        downloaded_files = dl_manager.download_and_extract(urls_to_download)
        return [
            datasets.SplitGenerator(
                name=datasets.Split.TRAIN,
                gen_kwargs={
                    "local_dir": downloaded_files,
                    "split": "train"
                },
            ),
            datasets.SplitGenerator(
                name=datasets.Split.VALIDATION,
                gen_kwargs={
                    "local_dir": downloaded_files,
                    "split": "valid"
                },
            ),
            datasets.SplitGenerator(
                name=datasets.Split.TEST,
                gen_kwargs={
                    "local_dir": downloaded_files,
                    "split": "test"
                },
            ),
        ]

    def _generate_examples(self, local_dir: str, split: str):

        idx = 0

        for file in glob.glob(os.path.join(local_dir, "*", "data", "*", split, "labels", "*.txt")):
            objects = []
            with open(file) as f:
                for line in f:
                    cls, *bbox = line.strip().split()
                    objects.append({"category": _CATEGORIES[int(cls)], "bbox": list(map(float, bbox))})

            image_path = os.path.normpath(file).split(os.sep)
            image_path = os.path.join(*image_path[:-2], "images", image_path[-1].replace(".txt", ".jpg"))
            if file.startswith("/") and not image_path.startswith("/"):
                image_path = "/" + image_path

            with open(image_path, "rb") as f:
                image_bytes = f.read()
                f.seek(0)

            with Image.open(image_path) as im:
                width, height = im.size

            yield idx, {
                "image_id": f"{image_path[-4]}/{image_path[-1]}",
                "image": {"path": image_path, "bytes": image_bytes},
                "width": width,
                "height": height,
                "objects": objects,
            }
            idx += 1