import feedparser
from simple_logger_handler import setup_logger
import time
from urllib.error import URLError
from typing import Optional
from dataclasses import dataclass
from datetime import datetime

@dataclass
class EpisodeData:
	episode_date: str
	episode_description: str
	episode_link: str
	episode_number: str
	episode_title: str
	episode_ytid: str

logger = setup_logger(__name__)

def grab_latest_chapter_information(id: str, max_retries: int = 3) -> Optional[EpisodeData]:
	"""
	Fetches the latest episodes information from a Youtube RSS feed, with retries on network-related errors.

	Parameters:
		id: Youtube channel ID as a string.
		max_retries: Number of retry attempts if fetching the feed fails due to network issues.

	Returns:
		EpisodeData: A dataclass containing episode metadata:
			episode_date: Date when it was published in iso format (2025-11-30).
			episode_description: Episode description.
			episode_link: YouTube link.
			episode_number: Episode number.
			episode_title: Episode title.
			episode_ytid: Episode YouTube ID .
		Returns None if the feed has no entries or all retries are exhausted.

	Raises:
		ValueError: If the feed has no entries.
		Other network-related exceptions: If fetching fails after retries.
	"""

	rss_feed_url = f"https://www.youtube.com/feeds/videos.xml?channel_id={id}"
	attempt = 1

	while attempt <= max_retries:
		logger.debug(f"[Feed] Parsing feed URL: {rss_feed_url} (attempt {attempt}/{max_retries})")
		try:
			feed = feedparser.parse(rss_feed_url)

			if not feed.entries:
				logger.warning(f"[Feed] No entries found for feed {id}")
				return None

			latest_chapter_data = feed["entries"][0]
			episode_link = latest_chapter_data["link"]
			episode_title = latest_chapter_data["title"]
			episode_description = latest_chapter_data["summary"]
			episode_date = latest_chapter_data["published"]
			episode_date = datetime.fromisoformat(episode_date).date().isoformat()
			episode_ytid = latest_chapter_data["yt_videoid"]

			logger.info(f"[Feed] Latest episode '{episode_title}': {episode_link}")
			logger.debug(f"[Feed] Latest episode '{episode_title}' (YouTubeId {episode_ytid}): {episode_link} -> {episode_description}")
			return EpisodeData(
					episode_date=episode_date,
					episode_description=episode_description,
					episode_link=episode_link,
					episode_number="",
					episode_title=episode_title,
					episode_ytid=episode_ytid
			)

		except (URLError, OSError) as e:
			logger.warning(f"[Feed] Network error on attempt {attempt} for feed {id}: {e}")
			if attempt == max_retries:
				logger.error(f"[Feed] All {max_retries} attempts failed for feed {id}")
				return None
			backoff = 2 ** (attempt - 1)
			logger.debug(f"[Feed] Retrying in {backoff} seconds...")
			time.sleep(backoff)
			attempt += 1

if __name__ == "__main__":
	print(grab_latest_chapter_information("UCC3ehuUksTyQ7bbjGntmx3Q"))