from __future__ import annotations

import xml.etree.ElementTree as ET
from typing import Any, Dict, List

from intel.http_client import request
from intel.models import Candidate


ATOM_NS = {"atom": "http://www.w3.org/2005/Atom"}


def _node_text(node: ET.Element, path: str) -> str:
    child = node.find(path, ATOM_NS)
    return child.text.strip() if child is not None and child.text else ""


def fetch(system: Dict[str, Any], source: Dict[str, Any]) -> List[Candidate]:
    response = request("GET", source["url"], source=source)
    response.raise_for_status()
    root = ET.fromstring(response.content)

    parser_hints = source.get("parser_hints") or {}
    keywords = {kw.lower() for kw in (parser_hints.get("keywords") or source.get("keywords", []))}
    candidates: List[Candidate] = []
    entries = root.findall(".//atom:entry", ATOM_NS) or root.findall(".//entry")
    for entry in entries[: source.get("max_items", 50)]:
        title = _node_text(entry, "atom:title") or _node_text(entry, "title")
        link_node = entry.find("atom:link", ATOM_NS) or entry.find("link")
        link = ""
        if link_node is not None:
            link = (link_node.get("href") or "").strip()
        summary = _node_text(entry, "atom:summary") or _node_text(entry, "summary") or _node_text(entry, "atom:content")
        if keywords:
            haystack = " ".join(filter(None, [title, summary, link])).lower()
            if not any(keyword in haystack for keyword in keywords):
                continue
        candidates.append(
            Candidate(
                system_id=system["system_id"],
                display_name=system["display_name"],
                category=system["category"],
                advisory_mode=source.get("advisory_mode", "core"),
                source_kind=source["kind"],
                source_name=source["name"],
                source_confidence=source["confidence"],
                source_url=link or source["url"],
                title=title or f"Atom entry for {system['display_name']}",
                published_at=_node_text(entry, "atom:published") or _node_text(entry, "published"),
                updated_at=_node_text(entry, "atom:updated") or _node_text(entry, "updated"),
                summary=summary,
                severity="unknown",
                references=[link] if link else [source["url"]],
                raw={"title": title, "link": link},
            )
        )
    return candidates