import asyncio
import hashlib
import json
import time
import uuid
from http import HTTPStatus
from io import BytesIO
from typing import Dict, Optional, Tuple, Union
from urllib.parse import ParseResult, parse_qs, urlencode, urlparse, urlunparse

import async_timeout
import httpx
import pyqrcode
from fastapi import (
    Body,
    Depends,
    Header,
    Query,
    Request,
    Response,
    WebSocket,
    WebSocketDisconnect,
)
from fastapi.exceptions import HTTPException
from loguru import logger
from pydantic import BaseModel
from pydantic.fields import Field
from sse_starlette.sse import EventSourceResponse
from starlette.responses import RedirectResponse, StreamingResponse

from lnbits import bolt11, lnurl
from lnbits.core.models import Payment, Wallet
from lnbits.decorators import (
    WalletTypeInfo,
    check_admin,
    get_key_type,
    require_admin_key,
    require_invoice_key,
)
from lnbits.helpers import url_for
from lnbits.settings import get_wallet_class, settings
from lnbits.utils.exchange_rates import (
    currencies,
    fiat_amount_as_satoshis,
    satoshis_amount_as_fiat,
)

from .. import core_app, db
from ..crud import (
    create_tinyurl,
    delete_tinyurl,
    get_payments,
    get_standalone_payment,
    get_tinyurl,
    get_tinyurl_by_url,
    get_total_balance,
    get_wallet_for_key,
    save_balance_check,
    update_wallet,
)
from ..services import (
    InvoiceFailure,
    PaymentFailure,
    check_transaction_status,
    create_invoice,
    pay_invoice,
    perform_lnurlauth,
    websocketManager,
    websocketUpdater,
)
from ..tasks import api_invoice_listeners


@core_app.get("/api/v1/health", status_code=HTTPStatus.OK)
async def health():
    return


@core_app.get("/api/v1/wallet")
async def api_wallet(wallet: WalletTypeInfo = Depends(get_key_type)):
    if wallet.wallet_type == 0:
        return {
            "id": wallet.wallet.id,
            "name": wallet.wallet.name,
            "balance": wallet.wallet.balance_msat,
        }
    else:
        return {"name": wallet.wallet.name, "balance": wallet.wallet.balance_msat}


@core_app.put("/api/v1/wallet/{new_name}")
async def api_update_wallet(
    new_name: str, wallet: WalletTypeInfo = Depends(require_admin_key)
):
    await update_wallet(wallet.wallet.id, new_name)
    return {
        "id": wallet.wallet.id,
        "name": wallet.wallet.name,
        "balance": wallet.wallet.balance_msat,
    }


@core_app.get("/api/v1/payments")
async def api_payments(
    limit: Optional[int] = None,
    offset: Optional[int] = None,
    wallet: WalletTypeInfo = Depends(get_key_type),
):
    pendingPayments = await get_payments(
        wallet_id=wallet.wallet.id,
        pending=True,
        exclude_uncheckable=True,
        limit=limit,
        offset=offset,
    )
    for payment in pendingPayments:
        await check_transaction_status(
            wallet_id=payment.wallet_id, payment_hash=payment.payment_hash
        )
    return await get_payments(
        wallet_id=wallet.wallet.id,
        pending=True,
        complete=True,
        limit=limit,
        offset=offset,
    )


class CreateInvoiceData(BaseModel):
    out: Optional[bool] = True
    amount: float = Query(None, ge=0)
    memo: Optional[str] = None
    unit: Optional[str] = "sat"
    description_hash: Optional[str] = None
    unhashed_description: Optional[str] = None
    lnurl_callback: Optional[str] = None
    lnurl_balance_check: Optional[str] = None
    extra: Optional[dict] = None
    webhook: Optional[str] = None
    internal: Optional[bool] = False
    bolt11: Optional[str] = None


async def api_payments_create_invoice(data: CreateInvoiceData, wallet: Wallet):
    if data.description_hash or data.unhashed_description:
        try:
            description_hash = (
                bytes.fromhex(data.description_hash) if data.description_hash else b""
            )
            unhashed_description = (
                bytes.fromhex(data.unhashed_description)
                if data.unhashed_description
                else b""
            )
        except ValueError:
            raise HTTPException(
                status_code=HTTPStatus.BAD_REQUEST,
                detail="'description_hash' and 'unhashed_description' must be a valid hex strings",
            )
        memo = ""
    else:
        description_hash = b""
        unhashed_description = b""
        memo = data.memo or settings.lnbits_site_title

    if data.unit == "sat":
        amount = int(data.amount)
    else:
        assert data.unit is not None, "unit not set"
        price_in_sats = await fiat_amount_as_satoshis(data.amount, data.unit)
        amount = price_in_sats

    async with db.connect() as conn:
        try:
            payment_hash, payment_request = await create_invoice(
                wallet_id=wallet.id,
                amount=amount,
                memo=memo,
                description_hash=description_hash,
                unhashed_description=unhashed_description,
                extra=data.extra,
                webhook=data.webhook,
                internal=data.internal,
                conn=conn,
            )
        except InvoiceFailure as e:
            raise HTTPException(status_code=520, detail=str(e))
        except Exception as exc:
            raise exc

    invoice = bolt11.decode(payment_request)

    lnurl_response: Union[None, bool, str] = None
    if data.lnurl_callback:
        if data.lnurl_balance_check is not None:
            await save_balance_check(wallet.id, data.lnurl_balance_check)

        async with httpx.AsyncClient() as client:
            try:
                r = await client.get(
                    data.lnurl_callback,
                    params={
                        "pr": payment_request,
                        "balanceNotify": url_for(
                            f"/withdraw/notify/{urlparse(data.lnurl_callback).netloc}",
                            external=True,
                            wal=wallet.id,
                        ),
                    },
                    timeout=10,
                )
                if r.is_error:
                    lnurl_response = r.text
                else:
                    resp = json.loads(r.text)
                    if resp["status"] != "OK":
                        lnurl_response = resp["reason"]
                    else:
                        lnurl_response = True
            except (httpx.ConnectError, httpx.RequestError) as ex:
                logger.error(ex)
                lnurl_response = False

    return {
        "payment_hash": invoice.payment_hash,
        "payment_request": payment_request,
        # maintain backwards compatibility with API clients:
        "checking_id": invoice.payment_hash,
        "lnurl_response": lnurl_response,
    }


async def api_payments_pay_invoice(bolt11: str, wallet: Wallet):
    try:
        payment_hash = await pay_invoice(wallet_id=wallet.id, payment_request=bolt11)
    except ValueError as e:
        raise HTTPException(status_code=HTTPStatus.BAD_REQUEST, detail=str(e))
    except PermissionError as e:
        raise HTTPException(status_code=HTTPStatus.FORBIDDEN, detail=str(e))
    except PaymentFailure as e:
        raise HTTPException(status_code=520, detail=str(e))
    except Exception as exc:
        raise exc

    return {
        "payment_hash": payment_hash,
        # maintain backwards compatibility with API clients:
        "checking_id": payment_hash,
    }


@core_app.post(
    "/api/v1/payments",
    status_code=HTTPStatus.CREATED,
)
async def api_payments_create(
    wallet: WalletTypeInfo = Depends(require_invoice_key),
    invoiceData: CreateInvoiceData = Body(...),
):
    if invoiceData.out is True and wallet.wallet_type == 0:
        if not invoiceData.bolt11:
            raise HTTPException(
                status_code=HTTPStatus.BAD_REQUEST,
                detail="BOLT11 string is invalid or not given",
            )
        return await api_payments_pay_invoice(
            invoiceData.bolt11, wallet.wallet
        )  # admin key
    elif not invoiceData.out:
        # invoice key
        return await api_payments_create_invoice(invoiceData, wallet.wallet)
    else:
        raise HTTPException(
            status_code=HTTPStatus.UNAUTHORIZED,
            detail="Invoice (or Admin) key required.",
        )


class CreateLNURLData(BaseModel):
    description_hash: str
    callback: str
    amount: int
    comment: Optional[str] = None
    description: Optional[str] = None


@core_app.post("/api/v1/payments/lnurl")
async def api_payments_pay_lnurl(
    data: CreateLNURLData, wallet: WalletTypeInfo = Depends(require_admin_key)
):
    domain = urlparse(data.callback).netloc

    async with httpx.AsyncClient() as client:
        try:
            r = await client.get(
                data.callback,
                params={"amount": data.amount, "comment": data.comment},
                timeout=40,
            )
            if r.is_error:
                raise httpx.ConnectError("LNURL callback connection error")
        except (httpx.ConnectError, httpx.RequestError):
            raise HTTPException(
                status_code=HTTPStatus.BAD_REQUEST,
                detail=f"Failed to connect to {domain}.",
            )

    params = json.loads(r.text)
    if params.get("status") == "ERROR":
        raise HTTPException(
            status_code=HTTPStatus.BAD_REQUEST,
            detail=f"{domain} said: '{params.get('reason', '')}'",
        )

    if not params.get("pr"):
        raise HTTPException(
            status_code=HTTPStatus.BAD_REQUEST,
            detail=f"{domain} did not return a payment request.",
        )

    invoice = bolt11.decode(params["pr"])
    if invoice.amount_msat != data.amount:
        raise HTTPException(
            status_code=HTTPStatus.BAD_REQUEST,
            detail=f"{domain} returned an invalid invoice. Expected {data.amount} msat, got {invoice.amount_msat}.",
        )

    if invoice.description_hash != data.description_hash:
        raise HTTPException(
            status_code=HTTPStatus.BAD_REQUEST,
            detail=f"{domain} returned an invalid invoice. Expected description_hash == {data.description_hash}, got {invoice.description_hash}.",
        )

    extra = {}

    if params.get("successAction"):
        extra["success_action"] = params["successAction"]
    if data.comment:
        extra["comment"] = data.comment
    assert data.description is not None, "description is required"
    payment_hash = await pay_invoice(
        wallet_id=wallet.wallet.id,
        payment_request=params["pr"],
        description=data.description,
        extra=extra,
    )

    return {
        "success_action": params.get("successAction"),
        "payment_hash": payment_hash,
        # maintain backwards compatibility with API clients:
        "checking_id": payment_hash,
    }


async def subscribe_wallet_invoices(request: Request, wallet: Wallet):
    """
    Subscribe to new invoices for a wallet. Can be wrapped in EventSourceResponse.
    Listenes invoming payments for a wallet and yields jsons with payment details.
    """
    this_wallet_id = wallet.id

    payment_queue: asyncio.Queue[Payment] = asyncio.Queue(0)

    uid = f"{this_wallet_id}_{str(uuid.uuid4())[:8]}"
    logger.debug(f"adding sse listener for wallet: {uid}")
    api_invoice_listeners[uid] = payment_queue

    send_queue: asyncio.Queue[Tuple[str, Payment]] = asyncio.Queue(0)

    async def payment_received() -> None:
        while True:
            try:
                async with async_timeout.timeout(1):
                    payment: Payment = await payment_queue.get()
                    if payment.wallet_id == this_wallet_id:
                        logger.debug("sse listener: payment receieved", payment)
                        await send_queue.put(("payment-received", payment))
            except asyncio.TimeoutError:
                pass

    task = asyncio.create_task(payment_received())

    try:
        while True:
            if await request.is_disconnected():
                await request.close()
                break
            typ, data = await send_queue.get()
            if data:
                jdata = json.dumps(dict(data.dict(), pending=False))

            yield dict(data=jdata, event=typ)
    except asyncio.CancelledError:
        logger.debug(f"removing listener for wallet {uid}")
        api_invoice_listeners.pop(uid)
        task.cancel()
        return


@core_app.get("/api/v1/payments/sse")
async def api_payments_sse(
    request: Request, wallet: WalletTypeInfo = Depends(get_key_type)
):
    return EventSourceResponse(
        subscribe_wallet_invoices(request, wallet.wallet),
        ping=20,
        media_type="text/event-stream",
    )


@core_app.get("/api/v1/payments/{payment_hash}")
async def api_payment(payment_hash, X_Api_Key: Optional[str] = Header(None)):
    # We use X_Api_Key here because we want this call to work with and without keys
    # If a valid key is given, we also return the field "details", otherwise not
    wallet = await get_wallet_for_key(X_Api_Key) if type(X_Api_Key) == str else None

    # we have to specify the wallet id here, because postgres and sqlite return internal payments in different order
    # and get_standalone_payment otherwise just fetches the first one, causing unpredictable results
    payment = await get_standalone_payment(
        payment_hash, wallet_id=wallet.id if wallet else None
    )
    if payment is None:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Payment does not exist."
        )
    await check_transaction_status(payment.wallet_id, payment_hash)
    payment = await get_standalone_payment(
        payment_hash, wallet_id=wallet.id if wallet else None
    )
    if not payment:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Payment does not exist."
        )
    elif not payment.pending:
        if wallet and wallet.id == payment.wallet_id:
            return {"paid": True, "preimage": payment.preimage, "details": payment}
        return {"paid": True, "preimage": payment.preimage}

    try:
        await payment.check_status()
    except Exception:
        if wallet and wallet.id == payment.wallet_id:
            return {"paid": False, "details": payment}
        return {"paid": False}

    if wallet and wallet.id == payment.wallet_id:
        return {
            "paid": not payment.pending,
            "preimage": payment.preimage,
            "details": payment,
        }
    return {"paid": not payment.pending, "preimage": payment.preimage}


@core_app.get("/api/v1/lnurlscan/{code}")
async def api_lnurlscan(code: str, wallet: WalletTypeInfo = Depends(get_key_type)):
    try:
        url = lnurl.decode(code)
        domain = urlparse(url).netloc
    except:
        # parse internet identifier (user@domain.com)
        name_domain = code.split("@")
        if len(name_domain) == 2 and len(name_domain[1].split(".")) >= 2:
            name, domain = name_domain
            url = (
                ("http://" if domain.endswith(".onion") else "https://")
                + domain
                + "/.well-known/lnurlp/"
                + name
            )
            # will proceed with these values
        else:
            raise HTTPException(
                status_code=HTTPStatus.BAD_REQUEST, detail="invalid lnurl"
            )

    # params is what will be returned to the client
    params: Dict = {"domain": domain}

    if "tag=login" in url:
        params.update(kind="auth")
        params.update(callback=url)  # with k1 already in it

        lnurlauth_key = wallet.wallet.lnurlauth_key(domain)
        params.update(pubkey=lnurlauth_key.verifying_key.to_string("compressed").hex())
    else:
        async with httpx.AsyncClient() as client:
            r = await client.get(url, timeout=5)
            if r.is_error:
                raise HTTPException(
                    status_code=HTTPStatus.SERVICE_UNAVAILABLE,
                    detail={"domain": domain, "message": "failed to get parameters"},
                )

        try:
            data = json.loads(r.text)
        except json.decoder.JSONDecodeError:
            raise HTTPException(
                status_code=HTTPStatus.SERVICE_UNAVAILABLE,
                detail={
                    "domain": domain,
                    "message": f"got invalid response '{r.text[:200]}'",
                },
            )

        try:
            tag: str = data.get("tag")
            params.update(**data)
            if tag == "channelRequest":
                raise HTTPException(
                    status_code=HTTPStatus.BAD_REQUEST,
                    detail={
                        "domain": domain,
                        "kind": "channel",
                        "message": "unsupported",
                    },
                )
            elif tag == "withdrawRequest":
                params.update(kind="withdraw")
                params.update(fixed=data["minWithdrawable"] == data["maxWithdrawable"])

                # callback with k1 already in it
                parsed_callback: ParseResult = urlparse(data["callback"])
                qs: Dict = parse_qs(parsed_callback.query)
                qs["k1"] = data["k1"]

                # balanceCheck/balanceNotify
                if "balanceCheck" in data:
                    params.update(balanceCheck=data["balanceCheck"])

                # format callback url and send to client
                parsed_callback = parsed_callback._replace(
                    query=urlencode(qs, doseq=True)
                )
                params.update(callback=urlunparse(parsed_callback))
            elif tag == "payRequest":
                params.update(kind="pay")
                params.update(fixed=data["minSendable"] == data["maxSendable"])

                params.update(
                    description_hash=hashlib.sha256(
                        data["metadata"].encode()
                    ).hexdigest()
                )
                metadata = json.loads(data["metadata"])
                for [k, v] in metadata:
                    if k == "text/plain":
                        params.update(description=v)
                    if k == "image/jpeg;base64" or k == "image/png;base64":
                        data_uri = "data:" + k + "," + v
                        params.update(image=data_uri)
                    if k == "text/email" or k == "text/identifier":
                        params.update(targetUser=v)
                params.update(commentAllowed=data.get("commentAllowed", 0))

        except KeyError as exc:
            raise HTTPException(
                status_code=HTTPStatus.SERVICE_UNAVAILABLE,
                detail={
                    "domain": domain,
                    "message": f"lnurl JSON response invalid: {exc}",
                },
            )

    return params


class DecodePayment(BaseModel):
    data: str


@core_app.post("/api/v1/payments/decode", status_code=HTTPStatus.OK)
async def api_payments_decode(data: DecodePayment, response: Response):
    payment_str = data.data
    try:
        if payment_str[:5] == "LNURL":
            url = lnurl.decode(payment_str)
            return {"domain": url}
        else:
            invoice = bolt11.decode(payment_str)
            return {
                "payment_hash": invoice.payment_hash,
                "amount_msat": invoice.amount_msat,
                "description": invoice.description,
                "description_hash": invoice.description_hash,
                "payee": invoice.payee,
                "date": invoice.date,
                "expiry": invoice.expiry,
                "secret": invoice.secret,
                "route_hints": invoice.route_hints,
                "min_final_cltv_expiry": invoice.min_final_cltv_expiry,
            }
    except:
        response.status_code = HTTPStatus.BAD_REQUEST
        return {"message": "Failed to decode"}


class Callback(BaseModel):
    callback: str = Query(...)


@core_app.post("/api/v1/lnurlauth")
async def api_perform_lnurlauth(
    callback: Callback, wallet: WalletTypeInfo = Depends(require_admin_key)
):
    err = await perform_lnurlauth(callback.callback, wallet=wallet)
    if err:
        raise HTTPException(
            status_code=HTTPStatus.SERVICE_UNAVAILABLE, detail=err.reason
        )
    return ""


@core_app.get("/api/v1/currencies")
async def api_list_currencies_available():
    return list(currencies.keys())


class ConversionData(BaseModel):
    from_: str = Field("sat", alias="from")
    amount: float
    to: str = Query("usd")


@core_app.post("/api/v1/conversion")
async def api_fiat_as_sats(data: ConversionData):
    output = {}
    if data.from_ == "sat":
        output["BTC"] = data.amount / 100000000
        output["sats"] = int(data.amount)
        for currency in data.to.split(","):
            output[currency.strip().upper()] = await satoshis_amount_as_fiat(
                data.amount, currency.strip()
            )
        return output
    else:
        output[data.from_.upper()] = data.amount
        output["sats"] = await fiat_amount_as_satoshis(data.amount, data.from_)
        output["BTC"] = output["sats"] / 100000000
        return output


@core_app.get("/api/v1/qrcode/{data}", response_class=StreamingResponse)
async def img(request: Request, data):
    qr = pyqrcode.create(data)
    stream = BytesIO()
    qr.svg(stream, scale=3)
    stream.seek(0)

    async def _generator(stream: BytesIO):
        yield stream.getvalue()

    return StreamingResponse(
        _generator(stream),
        headers={
            "Content-Type": "image/svg+xml",
            "Cache-Control": "no-cache, no-store, must-revalidate",
            "Pragma": "no-cache",
            "Expires": "0",
        },
    )


@core_app.get("/api/v1/audit", dependencies=[Depends(check_admin)])
async def api_auditor():
    WALLET = get_wallet_class()
    total_balance = await get_total_balance()
    error_message, node_balance = await WALLET.status()

    if not error_message:
        delta = node_balance - total_balance
    else:
        node_balance, delta = None, None

    return {
        "node_balance_msats": int(node_balance),
        "lnbits_balance_msats": int(total_balance),
        "delta_msats": int(delta),
        "timestamp": int(time.time()),
    }


##################UNIVERSAL WEBSOCKET MANAGER########################


@core_app.websocket("/api/v1/ws/{item_id}")
async def websocket_connect(websocket: WebSocket, item_id: str):
    await websocketManager.connect(websocket)
    try:
        while True:
            data = await websocket.receive_text()
    except WebSocketDisconnect:
        websocketManager.disconnect(websocket)


@core_app.post("/api/v1/ws/{item_id}")
async def websocket_update_post(item_id: str, data: str):
    try:
        await websocketUpdater(item_id, data)
        return {"sent": True, "data": data}
    except:
        return {"sent": False, "data": data}


@core_app.get("/api/v1/ws/{item_id}/{data}")
async def websocket_update_get(item_id: str, data: str):
    try:
        await websocketUpdater(item_id, data)
        return {"sent": True, "data": data}
    except:
        return {"sent": False, "data": data}


############################TINYURL##################################


@core_app.post("/api/v1/tinyurl")
async def api_create_tinyurl(
    url: str, endless: bool = False, wallet: WalletTypeInfo = Depends(get_key_type)
):
    tinyurls = await get_tinyurl_by_url(url)
    try:
        for tinyurl in tinyurls:
            if tinyurl:
                if tinyurl.wallet == wallet.wallet.inkey:
                    return tinyurl
        return await create_tinyurl(url, endless, wallet.wallet.inkey)
    except:
        raise HTTPException(
            status_code=HTTPStatus.BAD_REQUEST, detail="Unable to create tinyurl"
        )


@core_app.get("/api/v1/tinyurl/{tinyurl_id}")
async def api_get_tinyurl(
    tinyurl_id: str, wallet: WalletTypeInfo = Depends(get_key_type)
):
    try:
        tinyurl = await get_tinyurl(tinyurl_id)
        if tinyurl:
            if tinyurl.wallet == wallet.wallet.inkey:
                return tinyurl
        raise HTTPException(
            status_code=HTTPStatus.FORBIDDEN, detail="Wrong key provided."
        )
    except:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Unable to fetch tinyurl"
        )


@core_app.delete("/api/v1/tinyurl/{tinyurl_id}")
async def api_delete_tinyurl(
    tinyurl_id: str, wallet: WalletTypeInfo = Depends(get_key_type)
):
    try:
        tinyurl = await get_tinyurl(tinyurl_id)
        if tinyurl:
            if tinyurl.wallet == wallet.wallet.inkey:
                await delete_tinyurl(tinyurl_id)
                return {"deleted": True}
        raise HTTPException(
            status_code=HTTPStatus.FORBIDDEN, detail="Wrong key provided."
        )
    except:
        raise HTTPException(
            status_code=HTTPStatus.BAD_REQUEST, detail="Unable to delete"
        )


@core_app.get("/t/{tinyurl_id}")
async def api_tinyurl(tinyurl_id: str):
    try:
        tinyurl = await get_tinyurl(tinyurl_id)
        if tinyurl:
            response = RedirectResponse(url=tinyurl.url)
            return response
        else:
            return
    except:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="unable to find tinyurl"
        )