# coding=utf-8
# Copyright 2020 The HuggingFace Datasets Authors and the current dataset script contributor.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import itertools
import json
import re
import sqlite3
from abc import abstractmethod
from functools import partial
from hashlib import md5
from multiprocessing import Pool
from pathlib import Path
from typing import Any, Dict, List, Optional, Iterator
import pyarrow as pa

from datetime import datetime
from urllib.parse import unquote_plus

import datasets
from datasets import load_dataset, Dataset
from langdetect import detect

# TODO: @thomasw21
_CITATION = """"""

# TODO: @thomasw21
_DESCRIPTION = """"""

# TODO: @thomasw21
_HOMEPAGE = ""

# TODO: @thomasw21
_LICENSE = ""

_FEATURES = datasets.Features(
    {
        # Some images provide an url others provide an Image. Both are exclusive.
        "image_url": datasets.Value("string"),
        "image": datasets.Image(),
        # An image can have multiple text associated with the same value. For example COCO.
        "texts": [datasets.Value("string")],
        # Define where the sample comes from, this is necessary when we start to use aggregated versions like PMD.
        "source": datasets.Value("string"),
        # We commit any kind of additional information in json format in `meta`
        "meta": datasets.Value("string"),
    }
)

def json_serializer(o):
    if isinstance(o, datetime):
        return str(o)

    raise TypeError(f"Object of type {o.__class__.__name__} is not JSON serializable")


class BaseLoader:
    def __init__(self, source: str, split: str, writer_batch_size: int):
        self.source = source
        self.split = split
        self.writer_batch_size = writer_batch_size

    @abstractmethod
    def _generate_batches(self):
        raise NotImplementedError()


class DatasetsLoader(BaseLoader):
    """Helper as some datasets are already implemented"""

    def __init__(
        self,
        dataset_name: str,
        config_name: Optional[str],
        split: str,
        num_proc: int,
        datasets_batch_size: int = 1000,
    ):
        super(DatasetsLoader, self).__init__(
            source=dataset_name, split=split, writer_batch_size=datasets_batch_size
        )
        self.dataset_name = dataset_name
        self.config_name = config_name
        self.num_proc = num_proc
        self.datasets_batch_size = datasets_batch_size

    @abstractmethod
    def cast_to_pmd_features(self, batch: Dict[str, List[Any]]) -> Dict[str, List[Any]]:
        """Return list of caster rows. Casted row are either PMD features"""
        raise NotImplementedError()

    def _generate_batch_table(self, batch_start: int, dset: Dataset) -> pa.Table:
        dataset_size = len(dset)
        batch_end = min(batch_start + self.datasets_batch_size, dataset_size)
        batch = dset[batch_start:batch_end]
        output_batch = self.cast_to_pmd_features(batch)
        return pa.table(_FEATURES.encode_batch(output_batch))

    def _generate_batches(self):
        dataset = load_dataset(self.dataset_name, self.config_name, split=self.split)
        dataset_size = len(dataset)

        # load batches and yield individual rows
        if self.num_proc == 1:
            for batch_start in range(0, dataset_size, self.datasets_batch_size):
                batch_casted_pmd_features = self._generate_batch_table(
                    dset=dataset, batch_start=batch_start
                )
                yield batch_casted_pmd_features

        # Parallel version
        else:
            assert self.num_proc > 1
            with Pool(self.num_proc) as pool:
                # TODO @thomasw21 figure out if we care about imap / imap_unordered
                batch_iterator = pool.imap(
                    partial(self._generate_batch_table, dset=dataset),
                    range(0, dataset_size, self.datasets_batch_size),
                )
                for batch_casted_pmd_features in batch_iterator:
                    yield batch_casted_pmd_features


class BaseLoaderWithDLManager(BaseLoader):
    """We use dl_manager to generate `gen_kwargs` needed in order to generate examples."""

    def __init__(
        self,
        dl_manager,
        source: str,
        split: str,
        num_proc: int,
        chunk_size: int,
        writer_batch_size: int = 10_000,
    ):
        super(BaseLoaderWithDLManager, self).__init__(
            source=source, split=split, writer_batch_size=writer_batch_size
        )
        self.gen_kwargs = self.generate_gen_kwargs(dl_manager)
        # Used for multiprocessing
        self.chunk_size = chunk_size
        self.num_proc = num_proc

    @abstractmethod
    def generate_gen_kwargs(self, dl_manager):
        raise NotImplementedError()

    @abstractmethod
    def _build_rows_iterator(self, chunk_size: int, **kwargs) -> Iterator[List[Any]]:
        raise NotImplementedError()

    @abstractmethod
    def _generate_examples(self, examples: List[Any], **kwargs) -> Dict[str, List[Any]]:
        raise NotImplementedError

    def _generate_tables(self, examples: List[Any], **kwargs) -> pa.Table:
        return pa.table(_FEATURES.encode_batch(self._generate_examples(examples, **kwargs)))

    def _generate_batches(self):
        rows_iterator = self._build_rows_iterator(chunk_size=self.chunk_size, **self.gen_kwargs)

        with Pool(self.num_proc) as pool:
            tables_iterator = pool.imap(
                partial(self._generate_tables, **self.gen_kwargs),
                rows_iterator,
                chunksize=1,
            )
            for table in tables_iterator:
                yield table


class COCOloader(BaseLoaderWithDLManager):
    # TODO @thomasw21 rely on offical coco integration as soon as it's ready.
    _ANNOTATION_URL = (
        "http://images.cocodataset.org/annotations/annotations_trainval2017.zip"
    )
    _IMAGES_URLS = {
        "train": "http://images.cocodataset.org/zips/train2017.zip",
        "validation": "http://images.cocodataset.org/zips/val2017.zip",
    }
    _SPLIT_MAP = {"train": "train2017", "validation": "val207"}

    def __init__(
        self,
        dl_manager,
        split: str,
        num_proc: int,
        chunk_size: int,
        writer_batch_size: int,
    ):
        super(COCOloader, self).__init__(
            dl_manager=dl_manager,
            source="coco",
            split=split,
            num_proc=num_proc,
            chunk_size=chunk_size,
            writer_batch_size=writer_batch_size,
        )

    def generate_gen_kwargs(self, dl_manager):
        annotation_file = (
            Path(dl_manager.download_and_extract(self._ANNOTATION_URL))
            / "annotations"
            / f"captions_{self._SPLIT_MAP[self.split]}.json"
        )
        image_folder = Path(
            dl_manager.download_and_extract(self._IMAGES_URLS[self.split])
        )
        return {
            "annotation_file": annotation_file,
            "base_image_path": image_folder / self._SPLIT_MAP[self.split],
        }

    def _build_rows_iterator(self, chunk_size: int, annotation_file: str, base_image_path: Path) -> Iterator[List[Any]]:
        with open(annotation_file, "r", encoding="utf-8") as fi:
            annotations = json.load(fi)

            # We're going to index all the annotations according to `image_id`
            annotations_per_image_id = {}
            for annotation in annotations["annotations"]:
                image_id = annotation["image_id"]
                if image_id in annotations_per_image_id:
                    annotations_per_image_id[image_id].append(annotation)
                else:
                    annotations_per_image_id[image_id] = [annotation]

            # yield chunks
            buffer = []
            for image_metadata in annotations["images"]:
                image_id = image_metadata["id"]
                for annotation in annotations_per_image_id[image_id]:
                    buffer.append({
                        "annotation": annotation,
                        "image_metadata": image_metadata
                    })
                    if len(buffer) == chunk_size:
                        yield buffer
                        buffer = []
	    # Getting the last batch
	    if len(buffer) > 0:
		    yield buffer

    def _generate_examples(self, examples: List[Any], annotation_file: str, base_image_path: Path) -> Dict[str, List[Any]]:
        return {
            "image_url": [None for _ in examples],
            "image": [str((base_image_path / f"{example['image_metadata']['id']:012}.jpg").absolute()) for example in examples],
            "texts": [example["annotation"]["caption"] for example in examples],
            "source": [self.source for _ in examples],
            "meta": [json.dumps(
                example,
                default=json_serializer,
                indent=2,
            ) for example in examples],
        }


class SBULoader(DatasetsLoader):
    def __init__(self, split: str, num_proc: int, datasets_batch_size: int = 1000):
        super(SBULoader, self).__init__(
            dataset_name="sbu_captions",
            config_name=None,
            split=split,
            datasets_batch_size=datasets_batch_size,
            num_proc=num_proc,
        )

    def cast_to_pmd_features(self, batch: Dict[str, List[Any]]) -> Dict[str, List[Any]]:
        metas = {k: v for k, v in batch.items() if k not in ["image_url", "caption"]}
        batch_size = len(next(iter(batch.values())))
        return {
            "image_url": batch["image_url"],
            "image": [None] * batch_size,
            "texts": [[caption] for caption in batch["caption"]],
            "source": [self.source] * batch_size,
            "meta": [
                json.dumps(
                    {key: value[batch_id] for key, value in metas.items()},
                    default=json_serializer,
                    indent=2,
                )
                for batch_id in range(batch_size)
            ],
        }


class LocalizedNarrativesOpenImagesLoader(BaseLoaderWithDLManager):
    _ANNOTATION_URLs = {
        "train": "https://storage.googleapis.com/localized-narratives/annotations/open_images_train_v6_captions.jsonl",
        "validation": (
            "https://storage.googleapis.com/localized-narratives/annotations/open_images_validation_captions.jsonl"
        ),
        "test": "https://storage.googleapis.com/localized-narratives/annotations/open_images_test_captions.jsonl",
    }

    def __init__(
        self,
        dl_manager,
        split: str,
        num_proc: int,
        chunk_size: int,
        writer_batch_size: int,
    ):
        super(LocalizedNarrativesOpenImagesLoader, self).__init__(
            dl_manager=dl_manager,
            source="localized_narratives__coco",
            split=split,
            num_proc=num_proc,
            chunk_size=chunk_size,
            writer_batch_size=writer_batch_size,
        )

    def generate_gen_kwargs(self, dl_manager):
        annotation_file = dl_manager.download(self._ANNOTATION_URLs[self.split])
        return {"annotation_file": annotation_file, "split": self.split}

    def _build_rows_iterator(self, chunk_size: int, annotation_file: str, split: str) -> Iterator[List[Any]]:
        with open(annotation_file, "r", encoding="utf-8") as fi:
            chunk = tuple(itertools.islice(fi, chunk_size))

            if not chunk:
                return

            yield chunk

    def _generate_examples(self, examples: List[Any], annotation_file: str, split: str) -> Dict[str, List[Any]]:
        annotations = [json.loads(line) for line in examples]

        # sanity check
        for annotation in annotations:
            assert "image_url" not in annotation

        return {
            "image_url": [f"https://s3.amazonaws.com/open-images-dataset/{split}/{annotation['image_id']}.jpg" for annotation in annotations],
            "image": [None for _ in annotations],
            "texts": [[annotation["caption"]] for annotation in annotations],
            "source": [self.source for _ in annotations],
            "meta": [json.dumps(
                annotation,
                default=json_serializer,
                indent=2,
            ) for annotation in annotations],
        }


class LocalizedNarrativesCOCOLoader(BaseLoaderWithDLManager):
    # TODO @thomasw21 rely on offical coco integration as soon as it's ready.
    _ANNOTATION_URLs = {
        "train": "https://storage.googleapis.com/localized-narratives/annotations/coco_train_captions.jsonl",
        "validation": "https://storage.googleapis.com/localized-narratives/annotations/coco_val_captions.jsonl",
    }
    _IMAGES_URLS = {
        "train": "http://images.cocodataset.org/zips/train2017.zip",
        "validation": "http://images.cocodataset.org/zips/val2017.zip",
    }
    _SPLIT_MAP = {"train": "train2017", "validation": "val207"}

    def __init__(
        self,
        dl_manager,
        split: str,
        num_proc: int,
        chunk_size: int,
        writer_batch_size: int,
    ):
        super(LocalizedNarrativesCOCOLoader, self).__init__(
            dl_manager=dl_manager,
            source="localized_narratives__coco",
            split=split,
            num_proc=num_proc,
            chunk_size=chunk_size,
            writer_batch_size=writer_batch_size,
        )

    def generate_gen_kwargs(self, dl_manager):
        annotation_file = dl_manager.download(self._ANNOTATION_URLs[self.split])
        image_folder = Path(
            dl_manager.download_and_extract(self._IMAGES_URLS[self.split])
        )
        return {
            "annotation_file": annotation_file,
            "base_image_path": image_folder / self._SPLIT_MAP[self.split],
        }

    def _build_rows_iterator(self, chunk_size: int, annotation_file: str, base_image_path: Path) -> Iterator[List[Any]]:
        with open(annotation_file, "r", encoding="utf-8") as fi:
            chunk = tuple(itertools.islice(fi, chunk_size))

            if not chunk:
                return

            yield chunk

    def _generate_examples(self, examples: List[Any], annotation_file: str, base_image_path: Path) -> Dict[str, List[Any]]:
        annotations = [json.loads(line) for line in examples]

        return {
            "image_url": [None for _ in examples],
            "image": [str((base_image_path / f"{annotation['image_id'].zfill(12)}.jpg").absolute()) for annotation in annotations],
            "texts": [[annotation["caption"]] for annotation in annotations],
            "source": [self.source for _ in annotations],
            "meta": [json.dumps(
                annotation,
                default=json_serializer,
                indent=2,
            ) for annotation in annotations],
        }

class LocalizedNarrativesFlickr30kLoader(BaseLoaderWithDLManager):
    _LOCAL_IMAGE_FOLDER_NAME = "flickr30k-images"
    _ANNOTATION_URLs = {
        "train": "https://storage.googleapis.com/localized-narratives/annotations/flickr30k_train_captions.jsonl",
        "validation": "https://storage.googleapis.com/localized-narratives/annotations/flickr30k_val_captions.jsonl",
        "test": "https://storage.googleapis.com/localized-narratives/annotations/flickr30k_test_captions.jsonl",
    }

    def __init__(
        self,
        dl_manager,
        split: str,
        num_proc: int,
        chunk_size: int,
        writer_batch_size: int,
    ):
        super(LocalizedNarrativesFlickr30kLoader, self).__init__(
            dl_manager=dl_manager,
            source="localized_narratives__flickr30k",
            split=split,
            num_proc=num_proc,
            chunk_size=chunk_size,
            writer_batch_size=writer_batch_size,
        )

    def generate_gen_kwargs(self, dl_manager):
        if dl_manager.manual_dir is None:
            raise FileNotFoundError(
                f"Please set manual dir via `datasets.load_dataset('pmd', data_dir={{PATH}})` where `{{PATH}}/flickr30k` includes `{self._LOCAL_IMAGE_FOLDER_NAME}`.\n. Manual download instructions: {self.manual_download_instruction}"
            )

        manual_dir = Path(dl_manager.manual_dir) / "flickr30k"
        if not manual_dir.exists():
            raise FileNotFoundError(
                f"Please set manual dir via `datasets.load_dataset('pmd', data_dir={{PATH}})` where `{{PATH}}/flickr30k` includes `{self._LOCAL_IMAGE_FOLDER_NAME}`.\n. Manual download instructions: {self.manual_download_instruction}"
            )

        annotation_file = dl_manager.download(self._ANNOTATION_URLs[self.split])

        return {"annotation_file": annotation_file, "base_image_path": manual_dir}

    @property
    def manual_download_instruction(self):
        return """\
            You need to go to http://shannon.cs.illinois.edu/DenotationGraph/data/index.html,
            and manually download the dataset ("Flickr 30k images."). Once it is completed,
            a file named `flickr30k-images.tar.gz` will appear in your Downloads folder
            or whichever folder your browser chooses to save files to. You then have
            to unzip the file and move `flickr30k-images` under <path/to/folder>/flickr30k.
            The <path/to/folder> can e.g. be "~/manual_data".
            dataset can then be loaded using the following command `datasets.load_dataset("pmd", data_dir="<path/to/folder>")`.
            """

    def _build_rows_iterator(self, chunk_size: int, annotation_file: str, base_image_path: Path) -> Iterator[List[Any]]:
        with open(annotation_file, "r", encoding="utf-8") as fi:
            chunk = tuple(itertools.islice(fi, chunk_size))

            if not chunk:
                return

            yield chunk

    def _generate_examples(self, examples: List[Any], annotation_file: str, base_image_path: Path) -> Dict[
        str, List[Any]]:
        annotations = [json.loads(line) for line in examples]

        return {
            "image_url": [None for _ in examples],
            "image": [str((base_image_path / f"{annotation['image_id']}.jpg").absolute()) for annotation in
                      annotations],
            "texts": [[annotation["caption"]] for annotation in annotations],
            "source": [self.source for _ in annotations],
            "meta": [json.dumps(
                annotation,
                default=json_serializer,
                indent=2,
            ) for annotation in annotations],
        }


class LocalizedNarrativesADE20kLoader(BaseLoaderWithDLManager):
    _ANNOTATION_URLs = {
        "train": "https://storage.googleapis.com/localized-narratives/annotations/ade20k_train_captions.jsonl",
        "validation": "https://storage.googleapis.com/localized-narratives/annotations/ade20k_validation_captions.jsonl",
    }
    _IMAGES_URL = (
        "http://data.csail.mit.edu/places/ADEchallenge/ADEChallengeData2016.zip"
    )
    _SPLIT_MAP = {"train": "training", "validation": "validation"}

    def __init__(
        self,
        dl_manager,
        split: str,
        num_proc: int,
        chunk_size: int,
        writer_batch_size: int,
    ):
        super(LocalizedNarrativesADE20kLoader, self).__init__(
            dl_manager=dl_manager,
            source="localized_narratives__ADE20k",
            split=split,
            num_proc=num_proc,
            chunk_size=chunk_size,
            writer_batch_size=writer_batch_size,
        )

    def generate_gen_kwargs(self, dl_manager):
        annotation_file = dl_manager.download(self._ANNOTATION_URLs[self.split])
        image_base_dir = (
            Path(dl_manager.download_and_extract(self._IMAGES_URL))
            / "ADEChallengeData2016"
            / "images"
        )

        return {
            "annotation_file": annotation_file,
            "base_image_path": image_base_dir / self._SPLIT_MAP[self.split],
        }

    def _build_rows_iterator(self, annotation_file: str, base_image_path: Path, chunk_size: int) -> Iterator[List[Any]]:
        with open(annotation_file, "r", encoding="utf-8") as fi:
            chunk = tuple(itertools.islice(fi, chunk_size))

            if not chunk:
                return

            yield chunk

    def _generate_examples(self, examples: List[Any], annotation_file: str, base_image_path: Path) -> Dict[str, Any]:
        annotations = [json.loads(line) for line in examples]
        return {
            "image_url": [None for _ in examples],
            "image": [str((base_image_path / f"{annotation['image_id']}.jpg").absolute()) for annotation in annotations],
            "texts": [annotation["caption"] for annotation in annotations],
            "source": [self.source for _ in examples],
            "meta": [json.dumps(
                annotation,
                default=json_serializer,
                indent=2,
            ) for annotation in annotations],
        }


class VisualGenomeLoader(DatasetsLoader):
    def __init__(self, split: str, num_proc: int, datasets_batch_size: int = 1000):
        super(VisualGenomeLoader, self).__init__(
            dataset_name="visual_genome",
            config_name="region_descriptions_v1.2.0",
            split=split,
            datasets_batch_size=datasets_batch_size,
            num_proc=num_proc,
        )

    def cast_to_pmd_features(self, batch: Dict[str, List[Any]]) -> Dict[str, List[Any]]:
        metas = {k: v for k, v in batch.items() if k not in ["image", "regions"]}
        input_batch_size = len(next(iter(batch.values())))
        serialized_metas = [
            json.dumps(
                {key: value[batch_id] for key, value in metas.items()},
                default=json_serializer,
                indent=2,
            )
            for batch_id in range(input_batch_size)
        ]
        output_list_rows = [
            {
                "image": image.crop(
                    (
                        region["x"],
                        region["y"],
                        region["x"] + region["width"],
                        region["y"] + region["height"],
                    )
                ),
                "image_url": None,
                "texts": [region["phrase"]],
                "source": self.source,
                "meta": serialized_meta,
            }
            for image, regions, serialized_meta in zip(
                batch["image"], batch["regions"], serialized_metas
            )
            for region in regions
        ]
        return {
            column_name: [row[column_name] for row in output_list_rows]
            for column_name in ["image_url", "image", "texts", "source", "meta"]
        }


class WITLoader(DatasetsLoader):
    def __init__(self, split: str, num_proc: int, datasets_batch_size: int = 1000):
        super(WITLoader, self).__init__(
            dataset_name="google/wit",
            config_name=None,
            split=split,
            datasets_batch_size=datasets_batch_size,
            num_proc=num_proc,
        )

    def cast_to_pmd_features(self, batch: Dict[str, List[Any]]) -> Dict[str, List[Any]]:
        metas = {k: v for k, v in batch.items() if k not in ["image_url"]}
        batch_size = len(next(iter(batch.values())))
        return {
            "image_url": batch["image_url"],
            "image": [None] * batch_size,
            "texts": [
                texts
                # TODO @thomasw21 figure out which one we should choose
                for texts in zip(
                    batch["caption_reference_description"],
                    batch["context_section_description"],
                    batch["caption_attribution_description"],
                )
            ],
            "source": [self.source] * batch_size,
            "meta": [
                json.dumps(
                    {key: value[batch_id] for key, value in metas.items()},
                    default=json_serializer,
                    indent=2,
                )
                for batch_id in range(batch_size)
            ],
        }


class ConceptualCaptions(DatasetsLoader):
    def __init__(self, split: str, num_proc: int, datasets_batch_size: int = 1000):
        super(ConceptualCaptions, self).__init__(
            dataset_name="conceptual_captions",
            config_name="unlabeled",
            split=split,
            datasets_batch_size=datasets_batch_size,
            num_proc=num_proc,
        )

    def cast_to_pmd_features(self, batch: Dict[str, List[Any]]) -> Dict[str, List[Any]]:
        metas = {k: v for k, v in batch.items() if k not in ["image_url", "caption"]}
        batch_size = len(next(iter(batch.values())))
        return {
            "image_url": batch["image_url"],
            "image": [None] * batch_size,
            "texts": [[caption] for caption in batch["caption"]],
            "source": [self.source] * batch_size,
            "meta": [
                json.dumps(
                    {key: value[batch_id] for key, value in metas.items()},
                    default=json_serializer,
                    indent=2,
                )
                for batch_id in range(batch_size)
            ],
        }


class Conceptual12MLoader(DatasetsLoader):
    def __init__(self, split: str, num_proc: int, datasets_batch_size: int = 1000):
        super(Conceptual12MLoader, self).__init__(
            dataset_name="conceptual_12m",
            config_name=None,
            split=split,
            datasets_batch_size=datasets_batch_size,
            num_proc=num_proc,
        )

    def cast_to_pmd_features(self, batch: Dict[str, List[Any]]) -> Dict[str, List[Any]]:
        metas = {k: v for k, v in batch.items() if k not in ["image_url", "caption"]}
        batch_size = len(next(iter(batch.values())))
        return {
            "image_url": batch["image_url"],
            "image": [None] * batch_size,
            "texts": [[caption] for caption in batch["caption"]],
            "source": [self.source] * batch_size,
            "meta": [
                json.dumps(
                    {key: value[batch_id] for key, value in metas.items()},
                    default=json_serializer,
                    indent=2,
                )
                for batch_id in range(batch_size)
            ],
        }


class RedCapsLoader(DatasetsLoader):
    def __init__(self, split: str, num_proc: int, datasets_batch_size: int = 1000):
        super(RedCapsLoader, self).__init__(
            dataset_name="red_caps",
            config_name="all",
            split=split,
            datasets_batch_size=datasets_batch_size,
            num_proc=num_proc,
        )

    def cast_to_pmd_features(self, batch: Dict[str, List[Any]]) -> Dict[str, List[Any]]:
        metas = {
            k: v for k, v in batch.items() if k not in ["image_url", "raw_caption"]
        }
        batch_size = len(next(iter(batch.values())))
        return {
            "image_url": batch["image_url"],
            "image": [None] * batch_size,
            "texts": [[caption] for caption in batch["raw_caption"]],
            "source": [self.source] * batch_size,
            "meta": [
                json.dumps(
                    {key: value[batch_id] for key, value in metas.items()},
                    default=json_serializer,
                    indent=2,
                )
                for batch_id in range(batch_size)
            ],
        }


class YFCC100MLoader(BaseLoaderWithDLManager):
    _ANNOTATION_URL = "https://multimedia-commons.s3-us-west-2.amazonaws.com/tools/etc/yfcc100m_dataset.sql"
    # Columns we're interested in
    _COLUMNS = [
        "photoid",
        "uid",
        "title",
        "description",
        "usertags",
        "downloadurl",
        "licensename",
        "licenseurl",
        "marker",
    ]
    # Text columns that are url encoded
    _TEXT_COLUMNS = ["title", "description", "usertags"]

    WHITE_SPACE_REGEX = re.compile(r"\s+")

    # Original YFCC100M filtering regexes
    LINE_BREAK_REGEX = re.compile(r"[\n\r]")
    REMOVE_HTML_TAGS_REGEX = re.compile(r"<.*?>")
    # TODO @thomasw21 improve that regex
    DATE_HOUR_REGEX = re.compile(r"[0-9](:|\.|-|/)[0-9][0-9](:|\.|-|/)[0-9][0-9]")
    WEIRD_CHARACTERS_REGEX = re.compile(r"[_©]")
    SECOND_WORD_REGEX = re.compile(r" [a-zA-Z]+")

    def __init__(
        self,
        dl_manager,
        split: str,
        num_proc: int,
        chunk_size: int,
        writer_batch_size: int,
    ):
        super(YFCC100MLoader, self).__init__(
            dl_manager=dl_manager,
            source="yfcc100m",
            split=split,
            num_proc=num_proc,
            chunk_size=chunk_size,
            writer_batch_size=writer_batch_size,
        )
        self.chunk_size = chunk_size

    # Code from https://gitlab.com/jfolz/yfcc100m/-/blob/master/yfcc100m/convert_metadata.py
    BYTE_MAP = {"%02x" % v: "%x" % v for v in range(256)}

    @classmethod
    def yfcc_local_path(cls, url, __bm=BYTE_MAP):
        h = md5(url.encode("utf-8")).hexdigest()
        hash_ = "".join(__bm[h[x : x + 2]] for x in range(0, 32, 2))
        return f"data/images/{hash_[0:3]}/{hash_[3:6]}/{hash_}.jpg"

    @classmethod
    def generate_image_url(cls, downloadurl: str):
        """Takes original image url, and download verion store in `multimedia-commons`"""
        # compute yfcc hash
        local_path = cls.yfcc_local_path(downloadurl)
        return f"https://multimedia-commons.s3-us-west-2.amazonaws.com/{local_path}"

    def generate_gen_kwargs(self, dl_manager):
        sql_file = dl_manager.download(self._ANNOTATION_URL)
        return {"sql_file": sql_file}

    def filter_text(self, text: str) -> bool:
        # # If less than two words return False
        # # TODO @thomasw21 we probably don't need to split all the way til the end ...
        # if len([substring for substring in self.WHITE_SPACE_REGEX.split(text) if substring != ""]) < 2:
        #     return False
        if self.WEIRD_CHARACTERS_REGEX.search(text) is not None:
            return False

        if self.SECOND_WORD_REGEX.search(text) is None:
            return False

        if self.DATE_HOUR_REGEX.search(text) is not None:
            return False

        # filter only english
        try:
            if detect(text) != "en":
                return False
        except Exception:
            return False

        return True

    def clean_text(self, text: str) -> str:
        """Inspired from original code"""
        cleaned_text = unquote_plus(text)
        cleaned_text = self.LINE_BREAK_REGEX.sub(" ", cleaned_text)
        cleaned_text = self.REMOVE_HTML_TAGS_REGEX.sub("", cleaned_text)
        return cleaned_text

    def get_associated_text(self, annotation: Dict[str, Any]) -> Optional[str]:
        """
        Given an annotation, return text associated to the image
        We return None when the annotation should be filtered out
        """
        ordered_text_columns_consideration = ["description", "title"]
        record_text = None
        for column_name in ordered_text_columns_consideration:
            text_candidate = annotation[column_name]
            if column_name == "description" and not (5 < len(text_candidate) < 256):
                continue
            cleaned_text_candidate = self.clean_text(text_candidate)
            if self.filter_text(cleaned_text_candidate):
                record_text = cleaned_text_candidate
                break
        return record_text

    def _build_rows_iterator(self, sql_file: str, chunk_size: int) -> Iterator[List[Any]]:
        # query records command
        sql_command = f"select {', '.join(self._COLUMNS)} from yfcc100m_dataset"

        # Create a connection and get a cursor
        with sqlite3.connect(sql_file) as connection:
            cursor = connection.cursor()

            # Execute the query
            cursor.execute(sql_command)
            # Get data in batches
            while True:
                # Read the data
                records = cursor.fetchmany(self.chunk_size)

                # If we are at the end
                if len(records) == 0:
                    break

                yield records

            cursor.close()

    def _generate_examples(self, examples: List[Any], sql_file: str) -> Dict[str, Any]:
        buffer = {}
        # Format data
        for example in examples:
            annotation = {
                column_name: value
                for value, column_name in zip(example, self._COLUMNS)
            }

            # TODO @thomasw21 if it's not an image we don't care for now
            if annotation["marker"] != 0:
                continue

            # We compute text candidate and skip the row if None work.
            text = self.get_associated_text(annotation)
            if text is None:
                continue

            for text_column in self._TEXT_COLUMNS:
                annotation[text_column] = unquote_plus(annotation[text_column])

            # add data to buffer
            temp_object = {
                # Add image_url that we download from s3 bucket instead of official download url
                "image_url": [self.generate_image_url(annotation["downloadurl"])],
                "image": [None],
                "texts": [[text]],
                "source": [self.source],
                "meta": [json.dumps(
                    annotation,
                    default=json_serializer,
                    indent=2,
                )],
            }
            if len(buffer) == 0:
                buffer = temp_object
            else:
                for column_name in buffer.keys():
                    buffer[column_name] += temp_object[column_name]
        return buffer


class PMDConfig(datasets.BuilderConfig):
    """BuilderConfig for PMD."""

    def __init__(
        self,
        num_proc: Optional[int] = None,
        datasets_batch_size: int = 1000,
        sqlite3_batch_size: int = 10_000,
        chunk_size: int = 10_000,
        writer_batch_size: int = 10_000,
        **kwargs,
    ):
        if num_proc is None:
            # We disable multiprocessing.
            num_proc = 1
        super(PMDConfig, self).__init__(**kwargs)
        # determines how much we can load
        self.datasets_batch_size = datasets_batch_size
        self.sqlite3_batch_size = sqlite3_batch_size

        # Some datasets should be loaded via multiprocessing.
        self.num_proc = num_proc
        self.chunk_size = chunk_size

        # Batch writing
        self.writer_batch_size = writer_batch_size


class PMD(datasets.ArrowBasedBuilder):
    """Builder for Open Images subset of PMD."""

    BUILDER_CONFIG_CLASS = PMDConfig

    def _info(self):
        return datasets.DatasetInfo(
            description=_DESCRIPTION,
            features=_FEATURES,
            homepage=_HOMEPAGE,
            license=_LICENSE,
            citation=_CITATION,
        )

    def _split_generators(self, dl_manager):
        return [
            datasets.SplitGenerator(
                name=split_name,
                gen_kwargs={
                    "loaders": [
                        COCOloader(
                            dl_manager=dl_manager,
                            split=split_name,
                            num_proc=self.config.num_proc,
                            chunk_size=self.config.chunk_size,
                            writer_batch_size=self.config.writer_batch_size,
                        ),
                        SBULoader(
                            split=split_name,
                            datasets_batch_size=self.config.datasets_batch_size,
                            num_proc=self.config.num_proc,
                        ),
                        LocalizedNarrativesOpenImagesLoader(
                            dl_manager=dl_manager,
                            split=split_name,
                            num_proc=self.config.num_proc,
                            chunk_size=self.config.chunk_size,
                            writer_batch_size=self.config.writer_batch_size,
                        ),
                        LocalizedNarrativesCOCOLoader(
                            dl_manager=dl_manager,
                            split=split_name,
                            num_proc=self.config.num_proc,
                            chunk_size=self.config.chunk_size,
                            writer_batch_size=self.config.writer_batch_size,
                        ),
                        LocalizedNarrativesFlickr30kLoader(
                            dl_manager=dl_manager,
                            split=split_name,
                            num_proc=self.config.num_proc,
                            chunk_size=self.config.chunk_size,
                            writer_batch_size=self.config.writer_batch_size,
                        ),
                        LocalizedNarrativesADE20kLoader(
                            dl_manager=dl_manager,
                            split=split_name,
                            num_proc=self.config.num_proc,
                            chunk_size=self.config.chunk_size,
                            writer_batch_size=self.config.writer_batch_size,
                        ),
                        ConceptualCaptions(
                            split=split_name,
                            num_proc=self.config.num_proc,
                            datasets_batch_size=self.config.datasets_batch_size,
                        ),
                        VisualGenomeLoader(
                            split=split_name,
                            num_proc=self.config.num_proc,
                            datasets_batch_size=self.config.datasets_batch_size,
                        ),
                        WITLoader(
                            split=split_name,
                            num_proc=self.config.num_proc,
                            datasets_batch_size=self.config.datasets_batch_size,
                        ),
                        Conceptual12MLoader(
                            split=split_name,
                            num_proc=self.config.num_proc,
                            datasets_batch_size=self.config.datasets_batch_size,
                        ),
                        RedCapsLoader(
                            split=split_name,
                            num_proc=self.config.num_proc,
                            datasets_batch_size=self.config.datasets_batch_size,
                        ),
                        YFCC100MLoader(
                            dl_manager=dl_manager,
                            split=split_name,
                            num_proc=self.config.num_proc,
                            chunk_size=self.config.sqlite3_batch_size,
                            writer_batch_size=self.config.writer_batch_size,
                        ),
                    ]
                },
            )
            for split_name in [datasets.Split.TRAIN]
        ]

    def _generate_tables(self, loaders: List[BaseLoader]):
        idx = 0
        print("start")
        for loader in loaders:
            print(loader.__class__.__name__)
            for elt in loader._generate_batches():
                yield idx, elt
                idx += 1