from __future__ import annotations

from dataclasses import dataclass
import json
import time
from typing import TYPE_CHECKING
import urllib.error
import urllib.request

from .youtube_objects import ChannelResult, SearchResult


if TYPE_CHECKING:
    import http.client
    import logging
    from .objects import HTTPHeaders


class YoutubeManager:
    DEFAULT_DAILY_REQUESTS = 10_000
    SHORTS_CHECK_STATUS = 303

    @dataclass
    class RateLimit:
        remaining: int
        next_reset: float

    def __init__(self, api_key: str, logger: logging.Logger):
        self._api_key = api_key
        self._logger = logger
        self.rate_limit = self.RateLimit(remaining=self.DEFAULT_DAILY_REQUESTS, next_reset=time.time() + 24 * 3600)

    def _request(self, url: str, request_timeout: float, expected_status: int = 200) -> tuple[HTTPHeaders, dict]:
        if time.time() >= self.rate_limit.next_reset:
            self.rate_limit.next_reset = time.time() + 24 * 3600
            self.rate_limit.remaining = self.DEFAULT_DAILY_REQUESTS
        elif self.rate_limit.remaining <= 0:
            sleep_time = time.time() - self.rate_limit.next_reset
            self._logger.debug('No more remaining in Youtube RateLimit : sleeping for %.03fs', sleep_time)
            time.sleep(sleep_time)
        self.rate_limit.remaining -= 1

        request = urllib.request.Request(url)
        request.add_header('Accept', 'application/json')
        try:
            with urllib.request.urlopen(request, timeout=request_timeout) as response:
                if response.status != expected_status:
                    raise RuntimeError(
                        f'Unexpected YT status {response.status} (expected: {expected_status})'
                        f' -> {response.read().decode()}')
                return dict(response.getheaders()), json.loads(response.read().decode())
        except urllib.error.HTTPError as error:
            raise RuntimeError(
                f'HTTP error calling API ({url}): {error}:\n'
                f'Headers:\n{error.headers}Body:\n{error.read()}') from error
        except urllib.error.URLError as error:
            raise RuntimeError(f'URL error calling YT API ({url}): {error}') from error
        except TimeoutError as error:
            raise RuntimeError(f'Timeout calling YT API ({url}): {error}') from error

    def is_shorts(self, connection: http.client.HTTPConnection, video_id: str) -> bool:
        try:
            connection.request('GET', f'/shorts/{video_id}')
            response = connection.getresponse()
            response.read()
            return response.status != self.SHORTS_CHECK_STATUS
        except Exception as error:
            raise RuntimeError(f'Exception calling YouTube shorts ({video_id}): {error}') from error

    def request_channel_info(self, channel_id: str, request_timeout: float) -> tuple[
            HTTPHeaders, ChannelResult]:
        url = ('https://www.googleapis.com/youtube/v3/channels?part=snippet'
               f'&id={channel_id}&key={self._api_key}')
        headers, info = self._request(url=url, request_timeout=request_timeout)
        return headers, ChannelResult.from_dict(info)

    def request_channel_videos(self, channel_id: str, max_results: int, request_timeout: float) -> tuple[
            HTTPHeaders, SearchResult]:
        url = (f'https://www.googleapis.com/youtube/v3/search?part=snippet&channelId={channel_id}'
               f'&maxResults={max_results}&order=date&type=video&key={self._api_key}')
        headers, info = self._request(url=url, request_timeout=request_timeout)
        return headers, SearchResult.from_dict(info)