"""HashSet dataset."""

import datasets
import pandas as pd
import json

_CITATION = """
@article{kodali2022hashset,
  title={HashSet--A Dataset For Hashtag Segmentation},
  author={Kodali, Prashant and Bhatnagar, Akshala and Ahuja, Naman and Shrivastava, Manish and Kumaraguru, Ponnurangam},
  journal={arXiv preprint arXiv:2201.06741},
  year={2022}
}
"""

_DESCRIPTION = """
Hashset is a new dataset consisiting on 1.9k manually annotated and 3.3M loosely supervised tweets for testing the 
efficiency of hashtag segmentation models. We compare State of The Art Hashtag Segmentation models on Hashset and other 
baseline datasets (STAN and BOUN). We compare and analyse the results across the datasets to argue that HashSet can act 
as a good benchmark for hashtag segmentation tasks.

HashSet Manual: contains 1.9k manually annotated hashtags. Each row consists of the hashtag, segmented 
hashtag ,named entity annotations, a list storing whether the hashtag contains mix of hindi and english 
tokens and/or contains non-english tokens.
"""
_URL = "https://raw.githubusercontent.com/prashantkodali/HashSet/master/datasets/hashset/HashSet-Manual.csv"

class HashSetManual(datasets.GeneratorBasedBuilder):

    VERSION = datasets.Version("1.0.0")

    def _info(self):
        return datasets.DatasetInfo(
            description=_DESCRIPTION,
            features=datasets.Features(
                {
                    "index": datasets.Value("int32"),
                    "hashtag": datasets.Value("string"),
                    "segmentation": datasets.Value("string"),
                    "spans": datasets.Sequence(
                        {
                            "start": datasets.Value("int32"),
                            "end": datasets.Value("int32"),
                            "text": datasets.Value("string")
                        }
                    ),
                    "source": datasets.Value("string"),
                    "gold_position": datasets.Value("int32"),
                    "mix": datasets.Value("bool"),
                    "other": datasets.Value("bool"),
                    "ner": datasets.Value("bool"),
                    "annotator_id": datasets.Value("int32"),
                    "annotation_id": datasets.Value("int32"),
                    "created_at": datasets.Value("timestamp[us]"),
                    "updated_at": datasets.Value("timestamp[us]"),
                    "lead_time": datasets.Value("float64"),
                    "rank": datasets.Sequence(
                        {
                            "position": datasets.Value("int32"),
                            "candidate": datasets.Value("string")
                        }
                    )
                }
            ),
            supervised_keys=None,
            homepage="https://github.com/prashantkodali/HashSet/",
            citation=_CITATION,
        )

    def _split_generators(self, dl_manager):
        downloaded_files = dl_manager.download(_URL)
        return [
            datasets.SplitGenerator(name=datasets.Split.TEST, gen_kwargs={"filepath": downloaded_files }),
        ]

    def _generate_examples(self, filepath):

        def read_language_labels(field):
            mix_label = "Hashtag has a mix of english and hindi tokens"
            other_label = "Hashtag has non english token "
            ner_label = "Hashtag has named entities"
            try:
                record = json.loads(field)
            except json.decoder.JSONDecodeError:
                record = {"choices": [field]}
            
            mix = False
            other = False
            ner = False
            if mix_label in record["choices"]:
                mix = True
            if other_label in record["choices"]:
                other = True
            if ner_label in record["choices"]:
                ner = True
            return mix, other, ner

        def read_entities(field):
            try:
                record = json.loads(field)
            except json.decoder.JSONDecodeError:
                return []
            output = []
            for row in record:
                output.append({
                    "start": row.get("start", None),
                    "end": row.get("end", None),
                    "text": row.get("text", None)
                })
            return output

        def read_rank(row):
            output = []
            for i in range(10):
                output.append({
                    "position": str(i+1),
                    "candidate": row[str(i+1)]
                })
            return output

        def get_gold_position(field):
            output = field.strip("$")
            try:
                return int(output)
            except ValueError:
                return None

        records = pd.read_csv(filepath).to_dict("records")
        for idx, row in enumerate(records):
            mix, other, ner = read_language_labels(row["mutlitoken"])
            yield idx, {
                    "index": row["Unnamed: 0"],
                    "hashtag": row["Hashtag"],
                    "segmentation": row["Final Segmentation"],
                    "spans": read_entities(row["charner"]),
                    "source": row["Source"],
                    "gold_position": get_gold_position(row["topk"]),
                    "mix": mix,
                    "other": other,
                    "ner": ner,
                    "annotator_id": int(row["annotator"]),
                    "annotation_id": int(row["annotation_id"]),
                    "created_at": row["created_at"],
                    "updated_at": row["updated_at"],
                    "lead_time": row["lead_time"],
                    "rank": read_rank(row)
                }