import base64
import re
from datetime import date, timedelta
from urllib.parse import unquote
from .base import BaseProfile

# Hardcoded in the QBook JS bundle — fixed for all Hotels UK properties
_AUTH_BASE = "5wv2AGgSxfRKvH92UzxHcbSRZNJBEMd8cAay2RY7qC8YBjSTdswMvvdw343X"
_BUNDLE_K = "ad7ec113c738d3f5fe9f89a7e58a4b74e8301128"

HEADERS = {
    "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36",
    "Accept": "application/json",
    "Referer": "https://web-bookings.hotels.uk.com/",
    "Origin": "https://web-bookings.hotels.uk.com",
}


def _build_auth(hotel_id: str, from_date: str, to_date: str) -> str:
    code_auth = base64.b64encode(
        f"{hotel_id}#{from_date}#{to_date}".encode()
    ).decode().rstrip("=")
    return _AUTH_BASE[:30] + code_auth + _AUTH_BASE[30:]


class QBookProfile(BaseProfile):
    name = "qbook"
    label = "QBook (Hotels UK)"
    required_params = [
        {"key": "hotel_id", "label": "Hotel ID",
         "help": "Numeric hotel ID from the booking URL, e.g. 51420"},
        {"key": "dk", "label": "Distribution Key",
         "help": "The k= value from the booking widget URL"},
    ]

    @classmethod
    def detect(cls, url: str) -> dict | None:
        m = re.search(r'web-bookings\.hotels\.uk\.com/#/booking/(\d+)', url)
        if not m:
            return None
        hotel_id = m.group(1)
        dk_match = re.search(r'[?&]k=([^&\s#]+)', url)
        dk = unquote(dk_match.group(1)) if dk_match else ""
        return {"hotel_id": hotel_id, "dk": dk}

    async def fetch_category_names(self, client, params: dict) -> tuple[dict, dict]:
        hotel_id = params["hotel_id"]
        dk = params["dk"]
        from datetime import date, timedelta
        tomorrow = (date.today() + timedelta(days=1)).isoformat()
        day_after = (date.today() + timedelta(days=2)).isoformat()
        try:
            r = await client.get(
                "https://web-bookings.hotels.uk.com/api/pull",
                params={
                    "HotelAvailability": "", "k": _BUNDLE_K,
                    "HotelID": hotel_id, "from": tomorrow, "to": day_after,
                    "json": "", "dk": dk, "Qbook": "",
                    "GHABooking": "", "CookieBooking": "", "COOKIE_HotelID": "",
                    "guests": "", "adultsCheck": "", "childAges": "",
                    "roomId": "", "revised": "",
                },
                headers={**HEADERS, "Auth": _build_auth(hotel_id, tomorrow, day_after)},
                timeout=20,
            )
        except Exception:
            return {}, {}
        if r.status_code != 200:
            return {}, {}
        room_names: dict[str, str] = {}
        for item_id, item in r.json().get("availability", {}).items():
            if isinstance(item, dict) and item.get("item_name"):
                room_names[str(item_id)] = item["item_name"]
        # QBook has no distinct rate plan names
        return room_names, {}

    async def fetch_arrival_dates(self, client, params: dict) -> list[str]:
        today = date.today()
        return [(today + timedelta(days=i)).isoformat() for i in range(1, 91)]

    async def fetch_night_rates(self, client, params: dict, arrival: str, nights: int = 1) -> list[dict]:
        hotel_id = params["hotel_id"]
        dk = params["dk"]
        departure = (date.fromisoformat(arrival) + timedelta(days=nights)).isoformat()

        try:
            r = await client.get(
                "https://web-bookings.hotels.uk.com/api/pull",
                params={
                    "HotelAvailability": "", "k": _BUNDLE_K,
                    "HotelID": hotel_id, "from": arrival, "to": departure,
                    "json": "", "dk": dk, "Qbook": "",
                    "GHABooking": "", "CookieBooking": "", "COOKIE_HotelID": "",
                    "guests": "", "adultsCheck": "", "childAges": "",
                    "roomId": "", "revised": "",
                },
                headers={**HEADERS, "Auth": _build_auth(hotel_id, arrival, departure)},
                timeout=20,
            )
        except Exception:
            return []

        if r.status_code != 200:
            return []

        availability = r.json().get("availability", {})
        if not isinstance(availability, dict):
            return []

        rooms = []
        for item_id, item in availability.items():
            if not isinstance(item, dict):
                continue
            avail_count = item.get("availableroom", 0)
            price = item.get("roomprice", 0.0)
            # roomprice=0 on an available room means no rate configured in QBook's backend
            if not price:
                continue
            rooms.append({
                "roomId": str(item_id),
                "rateId": "default",
                "availability": avail_count,
                "prices": [{"amountBeforeTax": price, "amountAfterTax": price}] * nights,
                "currencyCode": "GBP",
            })

        return rooms