from __future__ import annotations

import json

import httpx
from fastapi import APIRouter, HTTPException
from fastapi.responses import JSONResponse

from s2s_client.core import config as settings
from s2s_client.core import logging as app_logging
from s2s_client.models import requests as models_requests

router = APIRouter()


@router.post("/api/search")
async def search(req: models_requests.SearchRequest) -> JSONResponse:
    """Proxy a Google search via Serper.dev. The key stays on the server unless
    the user brought their own (then theirs is used for this request only)."""
    query = (req.query or "").strip()
    if not query:
        raise HTTPException(status_code=400, detail="La consulta está vacía.")

    key = (req.key or "").strip() or settings.SERPER_KEY
    has_user_key = bool((req.key or "").strip())
    if not key:
        # No server key and the user didn't supply one — search is unavailable.
        raise HTTPException(status_code=503, detail="La búsqueda no está configurada.")

    headers = {"X-API-KEY": key, "Content-Type": "application/json"}
    payload = {"q": query, "num": settings.MAX_RESULTS}
    app_logging.logger.debug(
        "[EXT][SERPER] search POST %s query=%s userKey=%s num=%d",
        settings.SERPER_URL,
        json.dumps(query, ensure_ascii=True)[:200],
        has_user_key,
        settings.MAX_RESULTS,
    )
    try:
        async with httpx.AsyncClient(timeout=12.0) as http:
            resp = await http.post(settings.SERPER_URL, headers=headers, json=payload)
    except httpx.RequestError as exc:
        app_logging.logger.warning("Serper unreachable: %r", exc)
        raise HTTPException(status_code=502, detail="No se puede conectar con el proveedor de búsqueda.")  # noqa: B904
    app_logging.logger.debug(
        "[EXT][SERPER] search RESP status=%s len=%dB",
        resp.status_code,
        len(resp.content or b""),
    )

    if resp.status_code != 200:
        # Serper's error body carries the real reason (e.g. "Not enough
        # credits") and contains no key, so it's safe to log and relay.
        body = resp.text[:300]
        app_logging.logger.warning("Serper error %s: %s", resp.status_code, body)
        msg = None
        try:
            msg = resp.json().get("message")
        except Exception:
            pass
        detail = f"Error del proveedor de búsqueda ({resp.status_code})"
        if msg:
            detail += f": {msg}"
        raise HTTPException(status_code=502, detail=detail)

    data = resp.json()
    results = []
    for item in (data.get("organic") or [])[: settings.MAX_RESULTS]:
        results.append(
            {
                "title": item.get("title", ""),
                "snippet": item.get("snippet", ""),
                "url": item.get("link", ""),
            }
        )

    # A direct answer when Google has one — saves the model a hop.
    box = data.get("answerBox") or {}
    answer = box.get("answer") or box.get("snippet") or None
    if not answer:
        kg = data.get("knowledgeGraph") or {}
        answer = kg.get("description") or None

    app_logging.logger.debug(
        "[EXT][SERPER] search PARSED hasAnswer=%s resultCount=%d titles=%s",
        bool(answer),
        len(results),
        [r.get("title", "")[:40] for r in results],
    )
    return JSONResponse({"query": query, "answer": answer, "results": results})