"""
Web Scraping and Article Extraction Module

Comprehensive web scraping capabilities for:
- News articles
- Analysis pieces
- Intelligence reports
- Research papers
- Real-time news feeds

Supports multiple extraction methods for robustness.
"""

import re
import requests
from datetime import datetime
from urllib.parse import urlparse
from typing import (
    List,
    Dict,
    Any,
    Tuple,
    Optional,
    Callable,
)

# -----------------------------------------------------
#                     WEB SCRAPER
# -----------------------------------------------------

class WebScraper:
    """
    General-purpose web scraper for geopolitical content.
    Handles various website structures and content types.
    """

    def __init__(self, user_agent: Optional[str] = None):
        self.user_agent = user_agent or "GeoBotv1/1.0 (Geopolitical Analysis)"
        self.session = requests.Session()
        self.session.headers.update({"User-Agent": self.user_agent})

    def fetch_url(self, url: str, timeout: int = 30) -> Dict[str, Any]:
        """Fetch raw HTML from a URL."""
        try:
            response = self.session.get(url, timeout=timeout)
            response.raise_for_status()
            return {
                "url": url,
                "status_code": response.status_code,
                "content": response.text,
                "headers": dict(response.headers),
                "encoding": response.encoding,
                "timestamp": datetime.now().isoformat(),
            }

        except requests.RequestException as e:
            return {
                "url": url,
                "error": str(e),
                "status_code": None,
                "content": None,
                "timestamp": datetime.now().isoformat(),
            }

    def parse_html(self, html_content: str) -> Dict[str, Any]:
        """Parse HTML using BeautifulSoup if available."""
        try:
            from bs4 import BeautifulSoup

            soup = BeautifulSoup(html_content, "html.parser")

            parsed = {
                "title": soup.title.string if soup.title else "",
                "text": soup.get_text(),
                "links": [a.get("href") for a in soup.find_all("a", href=True)],
                "images": [img.get("src") for img in soup.find_all("img", src=True)],
                "meta": {},
            }

            for meta in soup.find_all("meta"):
                name = meta.get("name") or meta.get("property")
                content = meta.get("content")
                if name and content:
                    parsed["meta"][name] = content

            return parsed

        except ImportError:
            # Fallback if soup is missing
            return {
                "title": "",
                "text": self._simple_html_strip(html_content),
                "links": [],
                "images": [],
                "meta": {},
            }

    def _simple_html_strip(self, html: str) -> str:
        """Simple fallback for removing HTML tags."""
        return re.sub(r"<[^>]+>", "", html)

    def scrape_url(self, url: str) -> Dict[str, Any]:
        """Fetch + parse a URL."""
        response = self.fetch_url(url)
        if response.get("error"):
            return response

        parsed = self.parse_html(response["content"])

        return {
            "url": url,
            "domain": urlparse(url).netloc,
            "title": parsed["title"],
            "text": parsed["text"],
            "meta": parsed["meta"],
            "links": parsed["links"],
            "images": parsed["images"],
            "timestamp": response["timestamp"],
            "status_code": response["status_code"],
        }


# -----------------------------------------------------
#                 ARTICLE EXTRACTION
# -----------------------------------------------------

class ArticleExtractor:
    """
    Wrapper for newspaper3k / trafilatura / fallback extraction.
    """

    def __init__(self, method: str = "auto"):
        self.method = method
        self._check_dependencies()

    def _check_dependencies(self) -> None:
        self.has_newspaper = False
        self.has_trafilatura = False

        try:
            import newspaper  # noqa
            self.has_newspaper = True
        except ImportError:
            pass

        try:
            import trafilatura  # noqa
            self.has_trafilatura = True
        except ImportError:
            pass

    def extract_article(self, url: str) -> Dict[str, Any]:
        """Choose extraction method based on dependencies."""
        method = self.method

        if method == "auto":
            if self.has_newspaper:
                method = "newspaper"
            elif self.has_trafilatura:
                method = "trafilatura"
            else:
                method = "basic"

        if method == "newspaper":
            return self._extract_with_newspaper(url)
        elif method == "trafilatura":
            return self._extract_with_trafilatura(url)
        else:
            return self._extract_basic(url)

    def _extract_with_newspaper(self, url: str) -> Dict[str, Any]:
        """Extract article using newspaper3k."""
        try:
            from newspaper import Article

            article = Article(url)
            article.download()
            article.parse()

            try:
                article.nlp()
                keywords = article.keywords
                summary = article.summary
            except Exception:
                keywords = []
                summary = ""

            return {
                "url": url,
                "title": article.title,
                "text": article.text,
                "authors": article.authors,
                "publish_date": article.publish_date.isoformat() if article.publish_date else None,
                "keywords": keywords,
                "summary": summary,
                "top_image": article.top_image,
                "images": list(article.images),
                "method": "newspaper",
                "timestamp": datetime.now().isoformat(),
            }

        except Exception as e:
            return {"url": url, "error": str(e), "method": "newspaper"}

    def _extract_with_trafilatura(self, url: str) -> Dict[str, Any]:
        """Extract article using trafilatura."""
        try:
            import trafilatura

            downloaded = trafilatura.fetch_url(url)
            text = trafilatura.extract(downloaded)
            metadata = trafilatura.extract_metadata(downloaded)

            return {
                "url": url,
                "title": metadata.title if metadata else "",
                "text": text or "",
                "authors": [metadata.author] if metadata and metadata.author else [],
                "publish_date": metadata.date if metadata else None,
                "description": metadata.description if metadata else "",
                "method": "trafilatura",
                "timestamp": datetime.now().isoformat(),
            }

        except Exception as e:
            return {"url": url, "error": str(e), "method": "trafilatura"}

    def _extract_basic(self, url: str) -> Dict[str, Any]:
        scraper = WebScraper()
        content = scraper.scrape_url(url)

        return {
            "url": url,
            "title": content.get("title", ""),
            "text": content.get("text", ""),
            "meta": content.get("meta", {}),
            "method": "basic",
            "timestamp": datetime.now().isoformat(),
        }

    def batch_extract(self, urls: List[str]) -> List[Dict[str, Any]]:
        articles = []
        for url in urls:
            try:
                articles.append(self.extract_article(url))
            except Exception as e:
                print(f"Error extracting {url}: {e}")
        return articles


# -----------------------------------------------------
#                NEWS AGGREGATOR
# -----------------------------------------------------

class NewsAggregator:
    """Aggregate RSS feeds + websites into normalized article objects."""

    def __init__(self):
        self.extractor = ArticleExtractor()
        self.sources: List[Dict[str, Any]] = []

    def add_source(self, name: str, url: str, source_type: str = "rss") -> None:
        self.sources.append({"name": name, "url": url, "type": source_type})

    def fetch_news(self, keywords: Optional[List[str]] = None) -> List[Dict[str, Any]]:
        articles = []

        for source in self.sources:
            try:
                if source["type"] == "rss":
                    pulled = self._fetch_rss(source["url"])
                else:
                    pulled = self._fetch_website(source["url"])

                for a in pulled:
                    a["source"] = source["name"]
                    if keywords:
                        txt = a.get("text", "").lower()
                        if any(kw.lower() in txt for kw in keywords):
                            articles.append(a)
                    else:
                        articles.append(a)

            except Exception as e:
                print(f"Error fetching from {source['name']}: {e}")

        return articles

    def _fetch_rss(self, rss_url: str) -> List[Dict[str, Any]]:
        try:
            import feedparser

            feed = feedparser.parse(rss_url)
            articles = []

            for entry in feed.entries:
                base = {
                    "title": entry.get("title", ""),
                    "url": entry.get("link", ""),
                    "summary": entry.get("summary", ""),
                    "publish_date": entry.get("published", ""),
                    "authors": [a.get("name") for a in entry.get("authors", [])],
                }

                if base["url"]:
                    try:
                        full = self.extractor.extract_article(base["url"])
                        base["text"] = full.get("text", base["summary"])
                    except Exception:
                        base["text"] = base["summary"]

                articles.append(base)

            return articles

        except ImportError:
            print("feedparser not installed: pip install feedparser")
            return []

    def _fetch_website(self, url: str) -> List[Dict[str, Any]]:
        article = self.extractor.extract_article(url)
        return [article] if not article.get("error") else []

    def monitor_sources(
        self,
        keywords: List[str],
        callback: Optional[Callable[[List[Dict[str, Any]]], None]] = None,
        interval: int = 3600,
    ) -> None:
        """Continuously monitor sources for new articles."""
        import time

        seen: set = set()

        while True:
            articles = self.fetch_news(keywords)
            new_articles = [a for a in articles if a["url"] not in seen]

            if new_articles and callback:
                callback(new_articles)

            seen.update(a["url"] for a in new_articles)

            time.sleep(interval)

    def get_trending_topics(
        self,
        articles: List[Dict[str, Any]],
        n_topics: int = 10
    ) -> List[Tuple[str, int]]:
        """Compute most common keywords."""
        from collections import Counter

        words = []
        stop = {
            "the", "a", "an", "and", "or", "but", "in", "on", "at",
            "to", "for", "of", "with", "by", "from"
        }

        for art in articles:
            text = (art.get("text", "") + " " + art.get("title", "")).lower()
            ws = [w for w in text.split() if len(w) > 3 and w not in stop]
            words.extend(ws)

        return Counter(words).most_common(n_topics)