"""
Webhook-сервер для приёма уведомлений от Heleket об оплате.

Heleket шлёт POST на url_callback когда статус счёта меняется.
Сервер верифицирует подпись, начисляет баланс и уведомляет пользователя в Telegram.
"""

import asyncio
import base64
import hashlib
import json
import logging
from datetime import datetime
from typing import Optional

from aiohttp import web

from config.settings import settings
from managers.storage import PaymentStorage, BalanceStorage, RubleBalanceStorage, PaymentHistoryStorage

logger = logging.getLogger(__name__)

HELEKET_IP = "31.133.220.8"


def _verify_sign(payload: dict, api_key: str) -> bool:
    """Верифицирует подпись webhook-запроса от Heleket.

    Алгоритм: md5( base64( json(payload_without_sign) ) + api_key )
    PHP json_encode() экранирует '/' как '\/', Python — нет, делаем вручную.
    """
    received_sign = payload.get("sign", "")
    data = {k: v for k, v in payload.items() if k != "sign"}
    data_json = json.dumps(data, separators=(",", ":"), ensure_ascii=False)
    data_json = data_json.replace("/", "\\/")
    data_b64 = base64.b64encode(data_json.encode("utf-8")).decode("utf-8")
    expected = hashlib.md5((data_b64 + api_key).encode("utf-8")).hexdigest()
    return expected == received_sign


class HelketWebhookServer:

    def __init__(
        self,
        payment_storage: PaymentStorage,
        balance_storage: BalanceStorage,
        rub_storage: RubleBalanceStorage,
        history_storage: PaymentHistoryStorage,
        bot,
        port: int = 8080,
    ):
        self._payment_storage = payment_storage
        self._balance_storage = balance_storage
        self._rub_storage = rub_storage
        self._history_storage = history_storage
        self._bot = bot
        self._port = port
        self._app = web.Application()
        self._runner: Optional[web.AppRunner] = None
        self._api_key = settings.HELEKET_API_KEY

        self._app.router.add_post("/heleket/webhook", self._handle_webhook)
        self._app.router.add_get("/health", self._handle_health)

    async def start(self) -> None:
        self._runner = web.AppRunner(self._app, access_log=None)
        await self._runner.setup()
        site = web.TCPSite(self._runner, "0.0.0.0", self._port)
        await site.start()
        logger.info(f"Heleket webhook server started on port {self._port}")

    async def stop(self) -> None:
        if self._runner:
            await self._runner.cleanup()
            logger.info("Heleket webhook server stopped")

    async def _handle_health(self, request: web.Request) -> web.Response:
        return web.Response(text="ok")

    async def _handle_webhook(self, request: web.Request) -> web.Response:
        client_ip = request.headers.get("X-Forwarded-For", request.remote)
        if settings.HELEKET_WHITELIST_IP and client_ip and HELEKET_IP not in client_ip:
            logger.warning(f"Webhook from unknown IP: {client_ip}")
            return web.Response(status=403, text="Forbidden")

        try:
            payload = await request.json()
        except Exception:
            logger.warning("Webhook: invalid JSON body")
            return web.Response(status=400, text="Bad Request")

        logger.info(f"Webhook received: uuid={payload.get('uuid')} status={payload.get('status')}")

        if self._api_key and not _verify_sign(payload, self._api_key):
            logger.warning(f"Webhook: invalid signature. uuid={payload.get('uuid')}")
            return web.Response(status=400, text="Invalid signature")

        status = payload.get("status", "")
        payment_uuid = payload.get("uuid", "")

        if status not in ("paid", "paid_over"):
            logger.info(f"Webhook: uuid={payment_uuid} status={status} — ignored")
            return web.Response(text="ok")

        payment = await self._payment_storage.get(payment_uuid)
        if not payment:
            logger.warning(f"Webhook: payment {payment_uuid} not found (already processed?)")
            return web.Response(text="ok")

        user_id = payment.get("user_id")
        chat_id = payment.get("chat_id") or user_id
        clicks = payment.get("clicks")
        rub = payment.get("rub", 0)

        try:
            if clicks:
                # Прямая покупка переходов — начисляем переходы
                await self._balance_storage.add_balance(user_id, clicks)
                msg = (
                    f"✅ Оплата получена!\n\n"
                    f"💳 Сумма: {rub} ₽\n"
                    f"🖱 Начислено: {clicks} переходов"
                )
                history_record = {
                    "type": "clicks",
                    "rub": rub,
                    "clicks": clicks,
                    "uuid": payment_uuid,
                    "at": datetime.now().isoformat(timespec="seconds"),
                }
                logger.info(f"Webhook: user={user_id} +{clicks} clicks")
            else:
                # Пополнение — начисляем только рубли, переходы пользователь купит сам
                await self._rub_storage.add_balance(user_id, rub)
                new_rub = await self._rub_storage.get_balance(user_id)
                msg = (
                    f"✅ Баланс пополнен!\n\n"
                    f"💳 Сумма: {rub} ₽\n"
                    f"🪙 Рублей на балансе: {new_rub} ₽\n\n"
                    f"Перейдите в кабинет чтобы купить переходы."
                )
                history_record = {
                    "type": "topup",
                    "rub": rub,
                    "uuid": payment_uuid,
                    "at": datetime.now().isoformat(timespec="seconds"),
                }
                logger.info(f"Webhook: user={user_id} +{rub} RUB")

            await self._payment_storage.delete(payment_uuid)
            await self._history_storage.add(user_id, history_record)

            if chat_id:
                from aiogram.types import InlineKeyboardButton
                from aiogram.utils.keyboard import InlineKeyboardBuilder
                builder = InlineKeyboardBuilder()
                builder.row(InlineKeyboardButton(text="🏠 Личный кабинет", callback_data="my_balance"))
                kb = builder.as_markup()

                msg_id = payment.get("msg_id")
                edited = False
                if msg_id:
                    try:
                        await self._bot.edit_message_text(
                            msg, chat_id=chat_id, message_id=msg_id,
                            reply_markup=kb
                        )
                        edited = True
                    except Exception:
                        pass

                if not edited:
                    try:
                        await self._bot.send_message(chat_id, msg, reply_markup=kb)
                    except Exception as e:
                        logger.warning(f"Webhook: failed to notify user {user_id}: {e}")

        except Exception as e:
            logger.error(f"Webhook: error processing {payment_uuid}: {e}", exc_info=True)
            return web.Response(status=500, text="Internal error")

        return web.Response(text="ok")