import os
from http import HTTPStatus
from logging import Logger
from time import sleep
from typing import List, Union

import requests

from apollo_notifications.user_data import exceptions
from apollo_notifications.user_data.config import UserDataConfig


class BaseUserDataClient:
    def __init__(self, config: UserDataConfig, logger: Logger):
        self._inner_api_prefix = "api"
        self._outer_api_prefix = "user-data-api"
        self._http_session = None
        self._logger = logger
        self._api_key = os.environ.get("USER_DATA_APIKEY", config.USER_DATA_APIKEY)
        schema = os.environ.get("USER_DATA_SCHEMA", config.USER_DATA_SCHEMA)
        host = os.environ.get("USER_DATA_HOST", config.USER_DATA_HOST)
        self._base_url = f"{schema}://{host}"
        self._app_slug = os.environ.get("USER_DATA_APP_HEADER", config.USER_DATA_APP_HEADER)
        self._retry_count = int(os.environ.get("USER_DATA_RETRY_COUNT", config.USER_DATA_RETRY_COUNT))
        self._retry_delay = int(os.environ.get("USER_DATA_RETRY_DELAY", config.USER_DATA_RETRY_DELAY))
        self._timeout = int(os.environ.get("USER_DATA_TIMEOUT", config.USER_DATA_TIMEOUT))
        self._batch_size = int(os.environ.get("USER_DATA_BATCH_SIZE", config.USER_DATA_BATCH_SIZE))

    @property
    def http_session(self):
        if not self._http_session:
            self._http_session = requests.Session()
            self._http_session.headers.update({"Authorization": self._api_key})
        return self._http_session

    def _send_request(self, request: requests.Request) -> Union[List[dict], dict]:
        retry_counter = 0

        while True:
            try:
                session = self.http_session
                response = session.send(session.prepare_request(request), timeout=self._timeout)
            except (ConnectionError, requests.Timeout) as exc:
                if retry_counter >= self._retry_count:
                    raise exceptions.UserDataUnavailable from exc
                self._logger.info(
                    f"{retry_counter}/{self._retry_count} Got exception {exc} on request to {request.url}."
                )
                retry_counter += 1
                sleep(self._retry_delay * retry_counter)
                continue

            try:
                result = response.json()
            except ValueError:
                raise exceptions.UserDataInvalidResponse(status_code=response.status_code)

            if response.status_code != HTTPStatus.OK:
                raise exceptions.UserDataInvalidResponse(response_data=result, status_code=response.status_code)

            return result