import discord
from discord.ext import commands
import asyncio
import requests
from xml.etree import ElementTree


RSS_URL_ARTICLES = "https://habr.com/ru/rss/hubs/artificial_intelligence/articles/top/daily/?fl=ru"
RSS_URL_POSTS = "https://habr.com/ru/rss/hubs/artificial_intelligence/news/top/daily/?fl=ru"


class News(commands.Cog):
    """Команда !news — свежие статьи по AI с Habr"""

    @commands.command(name="news")
    async def news(self, ctx):
        """Топ-5 свежих статей по AI с Habr"""
        articles = await self._fetch_rss(RSS_URL_ARTICLES)
        if articles is None:
            await ctx.send("Не удалось получить новости. Попробуйте позже.")
            return

        if not articles:
            await ctx.send("Новостей пока нет.")
            return

        await self._format_and_send(ctx, articles)

    async def _fetch_rss(self, url):
        """Скачать и распарсить RSS-ленту (RSS 2.0 / Atom)."""
        try:
            response = await asyncio.to_thread(requests.get, url, timeout=10)
            response.raise_for_status()
            root = ElementTree.fromstring(response.content)

            # RSS 2.0
            ns_dc = {"dc": "http://purl.org/dc/elements/1.1/"}
            items = root.findall(".//item")
            if not items:
                # Atom
                ns = {"atom": "http://www.w3.org/2005/Atom"}
                items = root.findall("atom:entry", ns)
            if not items:
                return []

            articles = []
            for entry in items:
                # RSS 2.0
                title_el = entry.find("title")
                date_el = entry.find("pubDate")
                creator_el = entry.find("dc:creator", ns_dc)
                categories = entry.findall("category")

                # guid с isPermaLink="true" для чистого URL
                guid_el = entry.find("guid[@isPermaLink='true']")
                link = guid_el.text if guid_el is not None else ""

                # Atom fallback
                if title_el is None:
                    ns = {"atom": "http://www.w3.org/2005/Atom"}
                    title_el = entry.find("atom:title", ns)
                    link_el = entry.find("atom:link", ns)
                    link = link_el.get("href", "") if link_el is not None else ""
                    date_el = entry.find("atom:published", ns)
                    creator_el = entry.find("atom:author/atom:name", ns)
                    categories = entry.findall("atom:category", ns)

                title = title_el.text if title_el is not None else "Без названия"
                pub_date = date_el.text if date_el is not None else ""
                creator = creator_el.text if creator_el is not None else ""
                tags = [cat.text for cat in categories if cat.text] if categories else []

                articles.append({
                    "title": title,
                    "link": link,
                    "pub_date": pub_date,
                    "creator": creator,
                    "tags": tags,
                })
            return articles[:10]
        except requests.RequestException:
            return None

    async def _format_and_send(self, ctx, articles):
        """Сформировать текст и отправить в чат."""
        lines = ["**Лучшие статьи за сутки / Искусственный интеллект / Хабr**\n<https://habr.com/ru/hubs/artificial_intelligence/articles/top/daily/>\n"]
        for i, article in enumerate(articles[:5], 1):
            from datetime import datetime
            date_str = ""
            if article["pub_date"]:
                try:
                    d = article["pub_date"].replace(" GMT", " +0000")
                    dt = datetime.strptime(d, "%a, %d %b %Y %H:%M:%S %z")
                    date_str = dt.strftime("%d.%m.%Y")
                except ValueError:
                    date_str = article["pub_date"][:10].replace("-", ".")
            title = article["title"]
            if len(title) > 60:
                title = title[:60] + "..."
            lines.append(f"{title}\n{date_str}   <{article['link']}>")

        # Второй блок: посты
        posts = await self._fetch_rss(RSS_URL_POSTS)
        if posts:
            lines.append("")
            lines.append("**Лучшие новости за сутки / Искусственный интеллект / Хабr**\n<https://habr.com/ru/hubs/artificial_intelligence/news/top/daily/>\n")
            for i, article in enumerate(posts[:5], 1):
                from datetime import datetime
                date_str = ""
                if article["pub_date"]:
                    try:
                        d = article["pub_date"].replace(" GMT", " +0000")
                        dt = datetime.strptime(d, "%a, %d %b %Y %H:%M:%S %z")
                        date_str = dt.strftime("%d.%m.%Y")
                    except ValueError:
                        date_str = article["pub_date"][:10].replace("-", ".")
                title = article["title"]
                if len(title) > 60:
                    title = title[:60] + "..."
                lines.append(f"{title}\n{date_str}   <{article['link']}>")

        message = "\n".join(lines).rstrip()
        await ctx.send(message, allowed_mentions=discord.AllowedMentions.none())