import asyncio

from fastapi.exceptions import HTTPException
from lnbits.helpers import url_for
import hmac
import httpx
from http import HTTPStatus
from os import getenv
from typing import Optional, AsyncGenerator

from .base import (
    StatusResponse,
    InvoiceResponse,
    PaymentResponse,
    PaymentStatus,
    Wallet,
    Unsupported,
)


class OpenNodeWallet(Wallet):
    """https://developers.opennode.com/"""

    def __init__(self):
        endpoint = getenv("OPENNODE_API_ENDPOINT")
        self.endpoint = endpoint[:-1] if endpoint.endswith("/") else endpoint

        key = (
            getenv("OPENNODE_KEY")
            or getenv("OPENNODE_ADMIN_KEY")
            or getenv("OPENNODE_INVOICE_KEY")
        )
        self.auth = {"Authorization": key}

    async def status(self) -> StatusResponse:
        try:
            async with httpx.AsyncClient() as client:
                r = await client.get(
                    f"{self.endpoint}/v1/account/balance", headers=self.auth, timeout=40
                )
        except (httpx.ConnectError, httpx.RequestError):
            return StatusResponse(f"Unable to connect to '{self.endpoint}'", 0)

        data = r.json()["data"]
        if r.is_error:
            return StatusResponse(data["message"], 0)

        return StatusResponse(None, data["balance"]["BTC"] / 100_000_000_000)

    async def create_invoice(
        self,
        amount: int,
        memo: Optional[str] = None,
        description_hash: Optional[bytes] = None,
    ) -> InvoiceResponse:
        if description_hash:
            raise Unsupported("description_hash")

        async with httpx.AsyncClient() as client:
            r = await client.post(
                f"{self.endpoint}/v1/charges",
                headers=self.auth,
                json={
                    "amount": amount,
                    "description": memo or "",
                    "callback_url": url_for("/webhook_listener", _external=True),
                },
                timeout=40,
            )

        if r.is_error:
            error_message = r.json()["message"]
            return InvoiceResponse(False, None, None, error_message)

        data = r.json()["data"]
        checking_id = data["id"]
        payment_request = data["lightning_invoice"]["payreq"]
        return InvoiceResponse(True, checking_id, payment_request, None)

    async def pay_invoice(self, bolt11: str, fee_limit_msat: int) -> PaymentResponse:
        async with httpx.AsyncClient() as client:
            r = await client.post(
                f"{self.endpoint}/v2/withdrawals",
                headers=self.auth,
                json={"type": "ln", "address": bolt11},
                timeout=180,
            )

        if r.is_error:
            error_message = r.json()["message"]
            return PaymentResponse(False, None, 0, None, error_message)

        data = r.json()["data"]
        checking_id = data["id"]
        fee_msat = data["fee"] * 1000
        return PaymentResponse(True, checking_id, fee_msat, None, None)

    async def get_invoice_status(self, checking_id: str) -> PaymentStatus:
        async with httpx.AsyncClient() as client:
            r = await client.get(
                f"{self.endpoint}/v1/charge/{checking_id}", headers=self.auth
            )
        if r.is_error:
            return PaymentStatus(None)

        statuses = {"processing": None, "paid": True, "unpaid": False}
        return PaymentStatus(statuses[r.json()["data"]["status"]])

    async def get_payment_status(self, checking_id: str) -> PaymentStatus:
        async with httpx.AsyncClient() as client:
            r = await client.get(
                f"{self.endpoint}/v1/withdrawal/{checking_id}", headers=self.auth
            )

        if r.is_error:
            return PaymentStatus(None)

        statuses = {
            "initial": None,
            "pending": None,
            "confirmed": True,
            "error": False,
            "failed": False,
        }
        return PaymentStatus(statuses[r.json()["data"]["status"]])

    async def paid_invoices_stream(self) -> AsyncGenerator[str, None]:
        self.queue = asyncio.Queue(0)
        while True:
            value = await self.queue.get()
            yield value

    async def webhook_listener(self):
        data = await request.form
        if "status" not in data or data["status"] != "paid":
            raise HTTPException(status_code=HTTPStatus.NO_CONTENT)

        charge_id = data["id"]
        x = hmac.new(self.auth["Authorization"].encode("ascii"), digestmod="sha256")
        x.update(charge_id.encode("ascii"))
        if x.hexdigest() != data["hashed_order"]:
            print("invalid webhook, not from opennode")
            raise HTTPException(status_code=HTTPStatus.NO_CONTENT)

        await self.queue.put(charge_id)
        raise HTTPException(status_code=HTTPStatus.NO_CONTENT)