import dataclasses
import datetime
import logging
from collections.abc import Iterator, Mapping

import requests_util

from personal_data.data import DeduplicateMode, Scraper

from .. import secrets

logger = logging.getLogger(__name__)

URL_API_ROOT = 'https://api.wanikani.com/v2'
URL_ASSIGNMENTS = URL_API_ROOT + '/assignments'
URL_SUBJECTS = URL_API_ROOT + '/subjects/{subject_id}'


@dataclasses.dataclass(frozen=True)
class WaniKaniLessonsFetcher(Scraper):
    dataset_name = 'wanikani_lessons'
    deduplicate_mode = DeduplicateMode.BY_ALL_COLUMNS

    def _setup_cache(self):
        requests_util.setup_limiter(
            self.session,
            URL_API_ROOT,
            expire_after=datetime.timedelta(days=90),
            per_minute=30,
        )
        requests_util.setup_limiter(
            self.session,
            URL_ASSIGNMENTS,
            expire_after=datetime.timedelta(days=3),
            per_minute=30,
        )

    def scrape(self) -> Iterator[Mapping[str, object]]:
        """Fetch assignments from the WaniKani API and yield a dict for each assignment with a non-null unlocked_at timestamp."""
        self._setup_cache()
        headers = {
            'Authorization': f'Bearer {secrets.wanikani_api_key()}',
            'Wanikani-Revision': '20170710',
        }
        url = URL_ASSIGNMENTS
        while url:
            logger.warning('Getting: %s', url)
            response = self.session.get(url, headers=headers)
            response.raise_for_status()
            json_resp = response.json()
            for assignment in json_resp.get('data', []):
                data_item = assignment['data']
                subject_id = data_item.get('subject_id')
                if subject_id:
                    subj_url = URL_SUBJECTS.format(subject_id=subject_id)
                    logger.warning('Getting: %s', subj_url)
                    subj_response = self.session.get(subj_url, headers=headers)
                    subj_response.raise_for_status()
                    subj_json = subj_response.json()
                    subject_characters = subj_json.get('data', {}).get('characters')
                    data_item['subject_characters'] = subject_characters
                yield data_item
            url = json_resp.get('pages', {}).get('next_url')