from typing import List
import re
import httpx
from .base import fetch_json, normalize_result


async def search_serpapi(query: str, limit: int = 20, api_key: str = "", **kwargs) -> List[dict]:
    if not api_key:
        return []
    try:
        params = {"engine": "google_scholar", "q": query, "num": min(limit, 20), "api_key": api_key}
        data = await fetch_json("https://serpapi.com/search.json", params=params)
        if "error" in data:
            return []
        results = []
        for item in data.get("organic_results", []):
            title = item.get("title", "")
            snippet = item.get("snippet", "")
            link = item.get("link", "")
            year = None
            if item.get("publication_info", {}).get("summary"):
                year_match = item["publication_info"]["summary"]
                y = re.search(r'(\d{4})', year_match)
                if y:
                    year = int(y.group(1))
            results.append(normalize_result(
                title=title,
                authors=[],
                year=year,
                abstract=snippet,
                pdf_url=link if "pdf" in link.lower() else "",
                source="Google Scholar",
            ))
        return results[:limit]
    except Exception:
        return []