"""Spotify Charts API Wrapper module."""
from requests import Request
from requests import Session

from feed_ingestion.flows.spotify.spotify_api import SpotifyAPI


class SpotifyChartsAPI(SpotifyAPI):
    """Wrapper class to abstract loading data from Spotify API."""

    _resource_charts_url_by_country = (
        'https://provider-api.spotify.com/{version}/analytics/spotifycharts/'
        '{chart_type}-{country}-{frequency}/{year}/{month}/{day}')

    def _prepare_chart_request(
            self, resource_name, date, version, country, frequency,
            chart_type):
        """Prepare Spotify API request to charts endpoint.

        Args:
            resource_name (str): Name of resource to request.
            date (date or str): date instance or `YYYY-MM-DD` formatted string.
            version (str):  API version.
            country (str):  Country code argument.
            frequency (str):  Frequency of chart (e.g. daily, weekly).
            chart_type (str):  Chart type (e.g. regional, viral).

        Returns:
            PreparedRequest: Prepared Request.
        """
        year, month, day = self._parse_date(date)

        req = Request('GET', self._resource_charts_url_by_country.format(
            licensor_name=self.licensor_name,
            version=version,
            resource_name=resource_name,
            year=year,
            month=month,
            day=day,
            country=country,
            frequency=frequency,
            chart_type=chart_type,
            token=self.token), headers=self._get_auth_header_for_request())
        return req.prepare()

    def _request_charts_to_file(self, fd, resource_name, date, version,
                                country, frequency, chart_type):
        """Request data from Spotify API and write raw gzipped response to fd.

        Args:
            fd (file): File object or writable buffer.
            resource_name (str): Name of resource to request.
            date (date or str): date instance or `YYYY-MM-DD` formatted string.
            version (str):  API version.
            country (str):  Country code argument.
            frequency (str):  Frequency of chart (e.g. daily, weekly).
            chart_type (str):  Chart type (e.g. regional, viral).
        """
        req = self._prepare_chart_request(
            resource_name, date, version, country, frequency, chart_type)

        res = Session().send(req, stream=True)
        res.raise_for_status()

        for chunk in res.iter_content(chunk_size=1024*1024):
            fd.write(chunk)

        fd.flush()

    def get_charts_to_file(self, fd, date, country, frequency, chart_type):
        """Request Streams data and return json object.

        Args:
            fd (file): File object or writable buffer.
            date (date or str): date instance or `YYYY-MM-DD` formatted string.
            country (str):  Country code argument.
            frequency (str):  Frequency of chart (e.g. daily, weekly).
            chart_type (str):  Chart type (e.g. regional, viral).

        Returns:
            list: List of JSON objects from Spotify response.
        """
        return self._request_charts_to_file(
            fd, 'chart', date, self.version, country, frequency, chart_type)