"""Bayut.com scraper.

Two operations:
- fetch_listing(url): read a listing detail page → ScrapedListing.
- search_similar(building, bedrooms, deal_type): search Bayut for similar candidates.

Bayut is a Next.js app; __NEXT_DATA__ contains the property in pageProps.
Unlike PF, Bayut shows the permit number as text in the JSON.
"""

from __future__ import annotations

import logging
import re
from urllib.parse import quote_plus, urljoin

from app.scrapers.base import (
    ScrapedListing,
    ScraperError,
    extract_next_data,
    fetch_html,
    parse_price,
)

logger = logging.getLogger(__name__)

BASE_URL = "https://www.bayut.com"
SOURCE = "bayut"


def _path_for_deal(deal_type: str) -> str:
    return "to-buy" if deal_type == "sale" else "to-rent"


def _walk(node):
    if isinstance(node, dict):
        yield node
        for v in node.values():
            yield from _walk(v)
    elif isinstance(node, list):
        for it in node:
            yield from _walk(it)


def _extract_price(item: dict) -> tuple[float | None, str | None]:
    price = item.get("price")
    if isinstance(price, dict):
        val = price.get("value") or price.get("amount")
        cur = price.get("currency") or "AED"
        return parse_price(val), cur
    if isinstance(price, (int, float, str)):
        return parse_price(price), "AED"
    return None, "AED"


def _extract_broker(item: dict) -> tuple[str | None, str | None]:
    agency = item.get("agency") or {}
    agency_name = agency.get("name") if isinstance(agency, dict) else None
    agent_name = item.get("contactName") or item.get("agentName") or item.get("ownerAgent", {}).get("name") if isinstance(item.get("ownerAgent"), dict) else item.get("contactName")
    return agent_name, agency_name


def _extract_permit(item: dict) -> str | None:
    for key in ("permitNumber", "permit_number", "rera", "trakheesi", "permit"):
        v = item.get(key)
        if v:
            return str(v).strip()
    return None


_ID_FROM_URL = re.compile(r"details-(\d+)\.html(?:[?#].*)?$")


def _extract_id_from_url(url: str) -> str | None:
    m = _ID_FROM_URL.search(url)
    return m.group(1) if m else None


def _is_listing_dict(item: dict) -> bool:
    if not isinstance(item, dict):
        return False
    has_price = "price" in item
    has_id = any(k in item for k in ("externalID", "id", "objectID"))
    return has_price and has_id


class BayutScraper:
    source = SOURCE

    def fetch_listing(self, url: str) -> ScrapedListing | None:
        try:
            html = fetch_html(url)
        except ScraperError as e:
            logger.warning("Bayut refetch failed for %s: %s", url, e)
            return None

        if not html:
            return ScrapedListing(
                source=SOURCE, external_id=_extract_id_from_url(url) or "", url=url,
                title=None, price=None, currency=None, permit_number=None,
                agent_name=None, agency_name=None, is_active=False,
            )

        data = extract_next_data(html)
        if not data:
            return None

        best = None
        best_score = -1
        for node in _walk(data):
            if not _is_listing_dict(node):
                continue
            score = 0
            if "title" in node or "name" in node:
                score += 2
            if "agency" in node or "contactName" in node:
                score += 2
            if "rooms" in node or "bedrooms" in node:
                score += 1
            if score > best_score:
                best_score = score
                best = node

        if best is None:
            logger.warning("Bayut: no listing dict found in __NEXT_DATA__ for %s", url)
            return None

        price, currency = _extract_price(best)
        agent_name, agency_name = _extract_broker(best)
        ext_id = (
            str(best.get("externalID") or best.get("id") or "")
            or _extract_id_from_url(url)
            or ""
        )
        return ScrapedListing(
            source=SOURCE,
            external_id=ext_id,
            url=url,
            title=best.get("title") or best.get("name"),
            price=price,
            currency=currency,
            permit_number=_extract_permit(best),
            agent_name=agent_name,
            agency_name=agency_name,
            is_active=True,
        )

    def search_similar(
        self,
        building: str | None,
        bedrooms: int | None,
        deal_type: str,
        limit: int = 20,
        location_url: str | None = None,
    ) -> list[ScrapedListing]:
        if not building:
            return []
        path = _path_for_deal(deal_type)
        q = quote_plus(building.strip())
        url = f"{BASE_URL}/{path}/property/dubai/?q={q}"
        if bedrooms is not None:
            url += f"&beds_in={bedrooms}"
        logger.info("Bayut search_similar: %s", url)

        try:
            html = fetch_html(url)
        except ScraperError as e:
            logger.warning("Bayut search failed: %s", e)
            return []

        data = extract_next_data(html)
        if not data:
            return []

        results: list[ScrapedListing] = []
        seen_ids: set[str] = set()
        for node in _walk(data):
            if not _is_listing_dict(node):
                continue
            ext_id = str(node.get("externalID") or node.get("id") or "")
            if not ext_id or ext_id in seen_ids:
                continue

            title = node.get("title") or node.get("name") or ""
            if building.lower() not in (title or "").lower():
                slug = str(node.get("slug") or "").lower()
                building_token = building.lower().replace(" ", "-")
                if building_token not in slug:
                    continue

            seen_ids.add(ext_id)
            price, currency = _extract_price(node)
            agent_name, agency_name = _extract_broker(node)
            cand_url = urljoin(BASE_URL, f"/property/details-{ext_id}.html")

            results.append(
                ScrapedListing(
                    source=SOURCE,
                    external_id=ext_id,
                    url=cand_url,
                    title=title or None,
                    price=price,
                    currency=currency,
                    permit_number=_extract_permit(node),
                    agent_name=agent_name,
                    agency_name=agency_name,
                    is_active=True,
                )
            )
            if len(results) >= limit:
                break
        return results