from contextlib import asynccontextmanager
from datetime import datetime, timezone
from os import environ

import asyncpraw
from async_lru import alru_cache
from fastapi import FastAPI, Response, HTTPException
from feedgen.feed import FeedGenerator


REDDIT_CLIENT_ID = environ["REDDIT_CLIENT_ID"]
REDDIT_CLIENT_SECRET = environ["REDDIT_CLIENT_SECRET"]
REDDIT_PASSWORD = environ["REDDIT_PASSWORD"]
REDDIT_USERNAME = environ["REDDIT_USERNAME"]
RSS_HOST = environ["RSS_HOST"]


@alru_cache(ttl=15 * 60)
async def fetch(feed, comments):
    fg = FeedGenerator()
    fg.id(f'{RSS_HOST}/{feed}')
    fg.title(f'r/{feed}')
    fg.link(href=f'{RSS_HOST}/{feed}')
    fg.description(f'r/{feed}')

    client = asyncpraw.Reddit(
        user_agent="stuff",
        client_id=REDDIT_CLIENT_ID,
        client_secret=REDDIT_CLIENT_SECRET,
        username=REDDIT_USERNAME,
        password=REDDIT_PASSWORD,
    )

    async with client as reddit:
        subreddit = await reddit.subreddit(feed)
        async for submission in subreddit.top(limit=30, time_filter="week"):
            if submission.selftext == "":
                continue

            fe = fg.add_entry()
            fe.id(submission.id)
            fe.title(submission.title)
            fe.link(href=submission.url)
            fe.pubDate(datetime.fromtimestamp(submission.created_utc, timezone.utc))
            author = 'none' if submission.author is None else submission.author.name
            content = f"<p>{author} ({submission.score})</p>"
            content += f"<p>{submission.selftext_html}</p>"
            if comments:
                comments = ""
                for comment in await submission.comments():
                    if isinstance(comment, asyncpraw.models.MoreComments):
                        continue
                    if comment.author is None:
                        continue
                    author = comment.author.name
                    if author.lower() == 'automoderator':
                        continue
                    comments += f"<li>{author} ({comment.score}) {comment.body_html}"
                content += f"<ul>{comments}</ul>"

            fe.content(content)

    rss = fg.rss_str(pretty=True)
    return rss


app = FastAPI()


@app.get("/{feed}")
async def root(feed: str, comments: bool = False):
    rss = await fetch(feed, comments)
    return Response(content=rss, media_type="application/xml")