lnbits-legend/lnbits/extensions/cashu/views_api.py

import json
import math
from http import HTTPStatus
from typing import Dict, List, Union

import httpx

# -------- cashu imports
from cashu.core.base import (
    BlindedSignature,
    CheckFeesRequest,
    CheckFeesResponse,
    CheckRequest,
    GetMeltResponse,
    GetMintResponse,
    Invoice,
    MeltRequest,
    MintRequest,
    PostSplitResponse,
    Proof,
    SplitRequest,
)
from fastapi import Query
from fastapi.params import Depends
from lnurl import decode as decode_lnurl
from loguru import logger
from secp256k1 import PublicKey
from starlette.exceptions import HTTPException

from lnbits import bolt11
from lnbits.core.crud import check_internal, get_user
from lnbits.core.services import (
    check_transaction_status,
    create_invoice,
    fee_reserve,
    pay_invoice,
)
from lnbits.core.views.api import api_payment
from lnbits.decorators import WalletTypeInfo, get_key_type, require_admin_key
from lnbits.helpers import urlsafe_short_hash
from lnbits.wallets.base import PaymentStatus

from . import cashu_ext, ledger
from .crud import create_cashu, delete_cashu, get_cashu, get_cashus
from .models import Cashu

# --------- extension imports


LIGHTNING = True

########################################
############### LNBITS MINTS ###########
########################################


@cashu_ext.get("/api/v1/mints", status_code=HTTPStatus.OK)
async def api_cashus(
    all_wallets: bool = Query(False), wallet: WalletTypeInfo = Depends(get_key_type)
):
    """
    Get all mints of this wallet.
    """
    wallet_ids = [wallet.wallet.id]
    if all_wallets:
        wallet_ids = (await get_user(wallet.wallet.user)).wallet_ids

    return [cashu.dict() for cashu in await get_cashus(wallet_ids)]


@cashu_ext.post("/api/v1/mints", status_code=HTTPStatus.CREATED)
async def api_cashu_create(data: Cashu, wallet: WalletTypeInfo = Depends(get_key_type)):
    """
    Create a new mint for this wallet.
    """
    cashu_id = urlsafe_short_hash()
    # generate a new keyset in cashu
    keyset = await ledger.load_keyset(cashu_id)

    cashu = await create_cashu(
        cashu_id=cashu_id, keyset_id=keyset.id, wallet_id=wallet.wallet.id, data=data
    )
    logger.debug(cashu)
    return cashu.dict()


@cashu_ext.delete("/api/v1/mints/{cashu_id}")
async def api_cashu_delete(
    cashu_id: str, wallet: WalletTypeInfo = Depends(require_admin_key)
):
    """
    Delete an existing cashu mint.
    """
    cashu = await get_cashu(cashu_id)

    if not cashu:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Cashu mint does not exist."
        )

    if cashu.wallet != wallet.wallet.id:
        raise HTTPException(
            status_code=HTTPStatus.FORBIDDEN, detail="Not your Cashu mint."
        )

    await delete_cashu(cashu_id)
    raise HTTPException(status_code=HTTPStatus.NO_CONTENT)


#######################################
########### CASHU ENDPOINTS ###########
#######################################


@cashu_ext.get("/api/v1/{cashu_id}/keys", status_code=HTTPStatus.OK)
async def keys(cashu_id: str = Query(None)) -> dict[int, str]:
    """Get the public keys of the mint"""
    cashu: Union[Cashu, None] = await get_cashu(cashu_id)

    if not cashu:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
        )

    return ledger.get_keyset(keyset_id=cashu.keyset_id)


@cashu_ext.get("/api/v1/{cashu_id}/keysets", status_code=HTTPStatus.OK)
async def keysets(cashu_id: str = Query(None)) -> dict[str, list[str]]:
    """Get the public keys of the mint"""
    cashu: Union[Cashu, None] = await get_cashu(cashu_id)

    if not cashu:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
        )

    return {"keysets": [cashu.keyset_id]}


@cashu_ext.get("/api/v1/{cashu_id}/mint")
async def request_mint(cashu_id: str = Query(None), amount: int = 0) -> GetMintResponse:
    """
    Request minting of new tokens. The mint responds with a Lightning invoice.
    This endpoint can be used for a Lightning invoice UX flow.

    Call `POST /mint` after paying the invoice.
    """
    cashu: Union[Cashu, None] = await get_cashu(cashu_id)

    if not cashu:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
        )

    # create an invoice that the wallet needs to pay
    try:
        payment_hash, payment_request = await create_invoice(
            wallet_id=cashu.wallet,
            amount=amount,
            memo=f"{cashu.name}",
            extra={"tag": "cashu"},
        )
        invoice = Invoice(
            amount=amount, pr=payment_request, hash=payment_hash, issued=False
        )
        # await store_lightning_invoice(cashu_id, invoice)
        await ledger.crud.store_lightning_invoice(invoice=invoice, db=ledger.db)
    except Exception as e:
        logger.error(e)
        raise HTTPException(status_code=HTTPStatus.INTERNAL_SERVER_ERROR, detail=str(e))

    print(f"Lightning invoice: {payment_request}")
    resp = GetMintResponse(pr=payment_request, hash=payment_hash)
    #     return {"pr": payment_request, "hash": payment_hash}
    return resp


@cashu_ext.post("/api/v1/{cashu_id}/mint")
async def mint_coins(
    data: MintRequest,
    cashu_id: str = Query(None),
    payment_hash: str = Query(None),
) -> List[BlindedSignature]:
    """
    Requests the minting of tokens belonging to a paid payment request.
    Call this endpoint after `GET /mint`.
    """
    cashu: Union[Cashu, None] = await get_cashu(cashu_id)
    if cashu is None:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
        )

    if LIGHTNING:
        invoice: Invoice = await ledger.crud.get_lightning_invoice(
            db=ledger.db, hash=payment_hash
        )
        if invoice is None:
            raise HTTPException(
                status_code=HTTPStatus.NOT_FOUND,
                detail="Mint does not know this invoice.",
            )
        if invoice.issued == True:
            raise HTTPException(
                status_code=HTTPStatus.PAYMENT_REQUIRED,
                detail="Tokens already issued for this invoice.",
            )

        total_requested = sum([bm.amount for bm in data.blinded_messages])
        if total_requested > invoice.amount:
            raise HTTPException(
                status_code=HTTPStatus.PAYMENT_REQUIRED,
                detail=f"Requested amount too high: {total_requested}. Invoice amount: {invoice.amount}",
            )

    status: PaymentStatus = await check_transaction_status(cashu.wallet, payment_hash)

    if status.paid != True:
        raise HTTPException(
            status_code=HTTPStatus.PAYMENT_REQUIRED, detail="Invoice not paid."
        )
    try:
        keyset = ledger.keysets.keysets[cashu.keyset_id]

        promises = await ledger._generate_promises(
            B_s=data.blinded_messages, keyset=keyset
        )
        assert len(promises), HTTPException(
            status_code=HTTPStatus.INTERNAL_SERVER_ERROR, detail="No promises returned."
        )
        await ledger.crud.update_lightning_invoice(
            db=ledger.db, hash=payment_hash, issued=True
        )

        return promises
    except Exception as e:
        logger.error(e)
        raise HTTPException(status_code=HTTPStatus.INTERNAL_SERVER_ERROR, detail=str(e))


@cashu_ext.post("/api/v1/{cashu_id}/melt")
async def melt_coins(
    payload: MeltRequest, cashu_id: str = Query(None)
) -> GetMeltResponse:
    """Invalidates proofs and pays a Lightning invoice."""
    cashu: Union[None, Cashu] = await get_cashu(cashu_id)
    if cashu is None:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
        )
    proofs = payload.proofs
    invoice = payload.invoice

    # !!!!!!! MAKE SURE THAT PROOFS ARE ONLY FROM THIS CASHU KEYSET ID
    # THIS IS NECESSARY BECAUSE THE CASHU BACKEND WILL ACCEPT ANY VALID
    # TOKENS
    assert all([p.id == cashu.keyset_id for p in proofs]), HTTPException(
        status_code=HTTPStatus.BAD_REQUEST,
        detail="Proofs include tokens from another mint.",
    )

    assert all([ledger._verify_proof(p) for p in proofs]), HTTPException(
        status_code=HTTPStatus.BAD_REQUEST,
        detail="Could not verify proofs.",
    )

    total_provided = sum([p["amount"] for p in proofs])
    invoice_obj = bolt11.decode(invoice)
    amount = math.ceil(invoice_obj.amount_msat / 1000)

    internal_checking_id = await check_internal(invoice_obj.payment_hash)

    if not internal_checking_id:
        fees_msat = fee_reserve(invoice_obj.amount_msat)
    else:
        fees_msat = 0
    assert total_provided >= amount + fees_msat / 1000, Exception(
        f"Provided proofs ({total_provided} sats) not enough for Lightning payment ({amount + fees_msat} sats)."
    )

    await pay_invoice(
        wallet_id=cashu.wallet,
        payment_request=invoice,
        description=f"pay cashu invoice",
        extra={"tag": "cashu", "cahsu_name": cashu.name},
    )

    status: PaymentStatus = await check_transaction_status(
        cashu.wallet, invoice_obj.payment_hash
    )
    if status.paid == True:
        await ledger._invalidate_proofs(proofs)
    return GetMeltResponse(paid=status.paid, preimage=status.preimage)


@cashu_ext.post("/api/v1/{cashu_id}/check")
async def check_spendable(
    payload: CheckRequest, cashu_id: str = Query(None)
) -> Dict[int, bool]:
    """Check whether a secret has been spent already or not."""
    cashu: Union[None, Cashu] = await get_cashu(cashu_id)
    if cashu is None:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
        )
    return await ledger.check_spendable(payload.proofs)


@cashu_ext.post("/api/v1/{cashu_id}/checkfees")
async def check_fees(
    payload: CheckFeesRequest, cashu_id: str = Query(None)
) -> CheckFeesResponse:
    """
    Responds with the fees necessary to pay a Lightning invoice.
    Used by wallets for figuring out the fees they need to supply.
    This is can be useful for checking whether an invoice is internal (Cashu-to-Cashu).
    """
    cashu: Union[None, Cashu] = await get_cashu(cashu_id)
    if cashu is None:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
        )
    invoice_obj = bolt11.decode(payload.pr)
    internal_checking_id = await check_internal(invoice_obj.payment_hash)

    if not internal_checking_id:
        fees_msat = fee_reserve(invoice_obj.amount_msat)
    else:
        fees_msat = 0
    return CheckFeesResponse(fee=fees_msat / 1000)


@cashu_ext.post("/api/v1/{cashu_id}/split")
async def split(
    payload: SplitRequest, cashu_id: str = Query(None)
) -> PostSplitResponse:
    """
    Requetst a set of tokens with amount "total" to be split into two
    newly minted sets with amount "split" and "total-split".
    """
    cashu: Union[None, Cashu] = await get_cashu(cashu_id)
    if cashu is None:
        raise HTTPException(
            status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
        )
    proofs = payload.proofs

    # !!!!!!! MAKE SURE THAT PROOFS ARE ONLY FROM THIS CASHU KEYSET ID
    # THIS IS NECESSARY BECAUSE THE CASHU BACKEND WILL ACCEPT ANY VALID
    # TOKENS
    assert all([p.id == cashu.keyset_id for p in proofs]), HTTPException(
        status_code=HTTPStatus.BAD_REQUEST,
        detail="Proofs include tokens from another mint.",
    )

    amount = payload.amount
    outputs = payload.outputs.blinded_messages
    assert outputs, Exception("no outputs provided.")
    split_return = None
    try:
        keyset = ledger.keysets.keysets[cashu.keyset_id]
        split_return = await ledger.split(proofs, amount, outputs, keyset)
    except Exception as exc:
        raise HTTPException(
            status_code=HTTPStatus.BAD_REQUEST,
            detail=str(exc),
        )
    if not split_return:
        raise HTTPException(
            status_code=HTTPStatus.BAD_REQUEST,
            detail="there was an error with the split",
        )
    frst_promises, scnd_promises = split_return
    resp = PostSplitResponse(fst=frst_promises, snd=scnd_promises)
    return resp


# @cashu_ext.post("/api/v1s/upodatekeys", status_code=HTTPStatus.CREATED)
# async def api_cashu_update_keys(
#     data: Cashu, wallet: WalletTypeInfo = Depends(get_key_type)
# ):
#     cashu = await get_cashu(data.id)

#     cashu = await create_cashu(wallet_id=wallet.wallet.id, data=data)
#     logger.debug(cashu)
#     return cashu.dict()


# ########################################
# #################????###################
# ########################################
# @cashu_ext.post("/api/v1s/{cashu_id}/invoices", status_code=HTTPStatus.CREATED)
# async def api_cashu_create_invoice(
#     amount: int = Query(..., ge=1), tipAmount: int = None, cashu_id: str = None
# ):
#     cashu = await get_cashu(cashu_id)

#     if not cashu:
#         raise HTTPException(
#             status_code=HTTPStatus.NOT_FOUND, detail="TPoS does not exist."
#         )

#     if tipAmount:
#         amount += tipAmount

#     try:
#         payment_hash, payment_request = await create_invoice(
#             wallet_id=cashu.wallet,
#             amount=amount,
#             memo=f"{cashu.name}",
#             extra={"tag": "cashu", "tipAmount": tipAmount, "cashuId": cashu_id},
#         )
#     except Exception as e:
#         raise HTTPException(status_code=HTTPStatus.INTERNAL_SERVER_ERROR, detail=str(e))

#     return {"payment_hash": payment_hash, "payment_request": payment_request}


# @cashu_ext.post(
#     "/api/v1s/{cashu_id}/invoices/{payment_request}/pay",
#     status_code=HTTPStatus.OK,
# )
# async def api_cashu_pay_invoice(
#     lnurl_data: PayLnurlWData, payment_request: str = None, cashu_id: str = None
# ):
#     cashu = await get_cashu(cashu_id)

#     if not cashu:
#         raise HTTPException(
#             status_code=HTTPStatus.NOT_FOUND, detail="TPoS does not exist."
#         )

#     lnurl = (
#         lnurl_data.lnurl.replace("lnurlw://", "")
#         .replace("lightning://", "")
#         .replace("LIGHTNING://", "")
#         .replace("lightning:", "")
#         .replace("LIGHTNING:", "")
#     )

#     if lnurl.lower().startswith("lnurl"):
#         lnurl = decode_lnurl(lnurl)
#     else:
#         lnurl = "https://" + lnurl

#     async with httpx.AsyncClient() as client:
#         try:
#             r = await client.get(lnurl, follow_redirects=True)
#             if r.is_error:
#                 lnurl_response = {"success": False, "detail": "Error loading"}
#             else:
#                 resp = r.json()
#                 if resp["tag"] != "withdrawRequest":
#                     lnurl_response = {"success": False, "detail": "Wrong tag type"}
#                 else:
#                     r2 = await client.get(
#                         resp["callback"],
#                         follow_redirects=True,
#                         params={
#                             "k1": resp["k1"],
#                             "pr": payment_request,
#                         },
#                     )
#                     resp2 = r2.json()
#                     if r2.is_error:
#                         lnurl_response = {
#                             "success": False,
#                             "detail": "Error loading callback",
#                         }
#                     elif resp2["status"] == "ERROR":
#                         lnurl_response = {"success": False, "detail": resp2["reason"]}
#                     else:
#                         lnurl_response = {"success": True, "detail": resp2}
#         except (httpx.ConnectError, httpx.RequestError):
#             lnurl_response = {"success": False, "detail": "Unexpected error occurred"}

#     return lnurl_response


# @cashu_ext.get(
#     "/api/v1s/{cashu_id}/invoices/{payment_hash}", status_code=HTTPStatus.OK
# )
# async def api_cashu_check_invoice(cashu_id: str, payment_hash: str):
#     cashu = await get_cashu(cashu_id)
#     if not cashu:
#         raise HTTPException(
#             status_code=HTTPStatus.NOT_FOUND, detail="TPoS does not exist."
#         )
#     try:
#         status = await api_payment(payment_hash)

#     except Exception as exc:
#         logger.error(exc)
#         return {"paid": False}
#     return status


# ########################################
# #################MINT###################
# ########################################


# # @cashu_ext.get("/api/v1/{cashu_id}/keys", status_code=HTTPStatus.OK)
# # async def keys(cashu_id: str = Query(False)):
# #     """Get the public keys of the mint"""
# #     mint = await get_cashu(cashu_id)
# #     if mint is None:
# #         raise HTTPException(
# #             status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
# #         )
# #     return get_pubkeys(mint.prvkey)


# @cashu_ext.get("/api/v1/{cashu_id}/mint")
# async def mint_pay_request(amount: int = 0, cashu_id: str = Query(None)):
#     """Request minting of tokens. Server responds with a Lightning invoice."""

#     cashu = await get_cashu(cashu_id)
#     if cashu is None:
#         raise HTTPException(
#             status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
#         )

#     try:
#         payment_hash, payment_request = await create_invoice(
#             wallet_id=cashu.wallet,
#             amount=amount,
#             memo=f"{cashu.name}",
#             extra={"tag": "cashu"},
#         )
#         invoice = Invoice(
#             amount=amount, pr=payment_request, hash=payment_hash, issued=False
#         )
#         await store_lightning_invoice(cashu_id, invoice)
#     except Exception as e:
#         logger.error(e)
#         raise HTTPException(status_code=HTTPStatus.INTERNAL_SERVER_ERROR, detail=str(e))

#     return {"pr": payment_request, "hash": payment_hash}


# @cashu_ext.post("/api/v1/{cashu_id}/mint")
# async def mint_coins(
#     data: MintPayloads,
#     cashu_id: str = Query(None),
#     payment_hash: Union[str, None] = None,
# ):
#     """
#     Requests the minting of tokens belonging to a paid payment request.
#     Call this endpoint after `GET /mint`.
#     """
#     cashu: Cashu = await get_cashu(cashu_id)
#     if cashu is None:
#         raise HTTPException(
#             status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
#         )
#     invoice: Invoice = (
#         None
#         if payment_hash == None
#         else await get_lightning_invoice(cashu_id, payment_hash)
#     )
#     if invoice is None:
#         raise HTTPException(
#             status_code=HTTPStatus.NOT_FOUND, detail="Mint does not have this invoice."
#         )
#     if invoice.issued == True:
#         raise HTTPException(
#             status_code=HTTPStatus.PAYMENT_REQUIRED,
#             detail="Tokens already issued for this invoice.",
#         )

#     total_requested = sum([bm.amount for bm in data.blinded_messages])
#     if total_requested > invoice.amount:
#         raise HTTPException(
#             status_code=HTTPStatus.PAYMENT_REQUIRED,
#             detail=f"Requested amount too high: {total_requested}. Invoice amount: {invoice.amount}",
#         )

#     status: PaymentStatus = await check_transaction_status(cashu.wallet, payment_hash)
#     # todo: revert to: status.paid != True:
#     if status.paid != True:
#         raise HTTPException(
#             status_code=HTTPStatus.PAYMENT_REQUIRED, detail="Invoice not paid."
#         )
#     try:
#         await update_lightning_invoice(cashu_id, payment_hash, True)

#         amounts = []
#         B_s = []
#         for payload in data.blinded_messages:
#             amounts.append(payload.amount)
#             B_s.append(PublicKey(bytes.fromhex(payload.B_), raw=True))

#         promises = await generate_promises(cashu.prvkey, amounts, B_s)
#         for amount, B_, p in zip(amounts, B_s, promises):
#             await store_promise(amount, B_.serialize().hex(), p.C_, cashu_id)

#         return promises
#     except Exception as e:
#         logger.error(e)
#         raise HTTPException(status_code=HTTPStatus.INTERNAL_SERVER_ERROR, detail=str(e))


# @cashu_ext.post("/api/v1/{cashu_id}/melt")
# async def melt_coins(payload: MeltPayload, cashu_id: str = Query(None)):
#     """Invalidates proofs and pays a Lightning invoice."""
#     cashu: Cashu = await get_cashu(cashu_id)
#     if cashu is None:
#         raise HTTPException(
#             status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
#         )
#     try:
#         ok, preimage = await melt(cashu, payload.proofs, payload.invoice)
#         return {"paid": ok, "preimage": preimage}
#     except Exception as e:
#         logger.error(e)
#         raise HTTPException(status_code=HTTPStatus.INTERNAL_SERVER_ERROR, detail=str(e))


# @cashu_ext.post("/api/v1/{cashu_id}/check")
# async def check_spendable_coins(payload: CheckPayload, cashu_id: str = Query(None)):
#     return await check_spendable(payload.proofs, cashu_id)


# @cashu_ext.post("/api/v1/{cashu_id}/split")
# async def split_proofs(payload: SplitRequest, cashu_id: str = Query(None)):
#     """
#     Requetst a set of tokens with amount "total" to be split into two
#     newly minted sets with amount "split" and "total-split".
#     """
#     print("### RECEIVE")
#     print("payload", json.dumps(payload, default=vars))
#     cashu: Cashu = await get_cashu(cashu_id)
#     if cashu is None:
#         raise HTTPException(
#             status_code=HTTPStatus.NOT_FOUND, detail="Mint does not exist."
#         )
#     proofs = payload.proofs
#     amount = payload.amount
#     outputs = payload.outputs.blinded_messages if payload.outputs else None
#     try:
#         split_return = await split(cashu, proofs, amount, outputs)
#     except Exception as exc:
#         raise CashuError(error=str(exc))
#     if not split_return:
#         return {"error": "there was a problem with the split."}
#     frst_promises, scnd_promises = split_return
#     resp = PostSplitResponse(fst=frst_promises, snd=scnd_promises)
#     print("### resp", json.dumps(resp, default=vars))
#     return resp


##################################################################
##################################################################
# CASHU LIB
##################################################################