wallet-core: implement and test currency conversion withdrawals

5 files changed, 121 insertions, 19 deletions

diff --git a/packages/taler-wallet-core/src/crypto/cryptoImplementation.ts b/packages/taler-wallet-core/src/crypto/cryptoImplementation.ts
index 56392f090..36ca128ae 100644
--- a/packages/taler-wallet-core/src/crypto/cryptoImplementation.ts
+++ b/packages/taler-wallet-core/src/crypto/cryptoImplementation.ts
@@ -164,7 +164,7 @@ export interface TalerCryptoInterface {
     req: ContractTermsValidationRequest,
   ): Promise<ValidationResult>;
 
-  createEddsaKeypair(req: unknown): Promise<EddsaKeypair>;
+  createEddsaKeypair(req: {}): Promise<EddsaKeypair>;
 
   eddsaGetPublic(req: EddsaGetPublicRequest): Promise<EddsaGetPublicResponse>;
 
diff --git a/packages/taler-wallet-core/src/db.ts b/packages/taler-wallet-core/src/db.ts
index 3e8452bcd..0cafae2a1 100644
--- a/packages/taler-wallet-core/src/db.ts
+++ b/packages/taler-wallet-core/src/db.ts
@@ -52,10 +52,10 @@ import {
   TalerPreciseTimestamp,
   TalerProtocolDuration,
   TalerProtocolTimestamp,
-  //TalerProtocolTimestamp,
   TransactionIdStr,
   UnblindedSignature,
   WireInfo,
+  WithdrawalAccountInfo,
   codecForAny,
 } from "@gnu-taler/taler-util";
 import { DbRetryInfo, TaskIdentifiers } from "./operations/common.js";
@@ -1373,6 +1373,11 @@ export interface WgInfoBankIntegrated {
 
 export interface WgInfoBankManual {
   withdrawalType: WithdrawalRecordType.BankManual;
+
+  /**
+   * Info about withdrawal accounts, possibly including currency conversion.
+   */
+  exchangeCreditAccounts?: WithdrawalAccountInfo[];
 }
 
 export interface WgInfoBankPeerPull {
diff --git a/packages/taler-wallet-core/src/operations/transactions.ts b/packages/taler-wallet-core/src/operations/transactions.ts
index 7ee6275b0..b294c163e 100644
--- a/packages/taler-wallet-core/src/operations/transactions.ts
+++ b/packages/taler-wallet-core/src/operations/transactions.ts
@@ -720,6 +720,7 @@ function buildTransactionForManualWithdraw(
       type: WithdrawalType.ManualTransfer,
       reservePub: withdrawalGroup.reservePub,
       exchangePaytoUris,
+      exchangeCreditAccounts: withdrawalGroup.wgInfo.exchangeCreditAccounts,
       reserveIsReady:
         withdrawalGroup.status === WithdrawalGroupStatus.Done ||
         withdrawalGroup.status === WithdrawalGroupStatus.PendingReady,
diff --git a/packages/taler-wallet-core/src/operations/withdraw.ts b/packages/taler-wallet-core/src/operations/withdraw.ts
index 275d0aaf0..a5a6bded8 100644
--- a/packages/taler-wallet-core/src/operations/withdraw.ts
+++ b/packages/taler-wallet-core/src/operations/withdraw.ts
@@ -24,6 +24,7 @@ import {
   AgeRestriction,
   AmountJson,
   AmountLike,
+  AmountString,
   Amounts,
   BankWithdrawDetails,
   CancellationToken,
@@ -42,6 +43,7 @@ import {
   LibtoolVersion,
   Logger,
   NotificationType,
+  PaytoUri,
   TalerError,
   TalerErrorCode,
   TalerErrorDetail,
@@ -54,21 +56,25 @@ import {
   TransactionType,
   URL,
   UnblindedSignature,
+  WireAccountDetails,
   WithdrawUriInfoResponse,
+  WithdrawalAccountInfo,
   addPaytoQueryParams,
   canonicalizeBaseUrl,
   codecForBankWithdrawalOperationPostResponse,
+  codecForCashinConversionResponse,
   codecForExchangeWithdrawBatchResponse,
   codecForIntegrationBankConfig,
   codecForReserveStatus,
   codecForWalletKycUuid,
   codecForWithdrawOperationStatusResponse,
+  createEddsaKeyPair,
   encodeCrock,
   getErrorDetailFromException,
   getRandomBytes,
   j2s,
   makeErrorDetail,
-  parseWithdrawUri
+  parseWithdrawUri,
 } from "@gnu-taler/taler-util";
 import {
   HttpRequestLibrary,
@@ -95,9 +101,8 @@ import {
 import {
   ExchangeDetailsRecord,
   ExchangeEntryDbRecordStatus,
-  PendingTaskType,
   isWithdrawableDenom,
-  timestampPreciseToDb
+  timestampPreciseToDb,
 } from "../index.js";
 import { InternalWalletState } from "../internal-wallet-state.js";
 import {
@@ -110,6 +115,7 @@ import {
   makeExchangeListItem,
   runLongpollAsync,
 } from "../operations/common.js";
+import { PendingTaskType } from "../pending-types.js";
 import { assertUnreachable } from "../util/assertUnreachable.js";
 import {
   selectForcedWithdrawalDenominations,
@@ -1751,8 +1757,23 @@ export async function getExchangeWithdrawalInfo(
   logger.trace("updating exchange");
   const { exchange, exchangeDetails } =
     await ws.exchangeOps.updateExchangeFromUrl(ws, exchangeBaseUrl);
+
+  if (exchangeDetails.currency != instructedAmount.currency) {
+    // Specifiying the amount in the conversion input currency is not yet supported.
+    // We might add support for it later.
+    throw new Error(
+      `withdrawal only supported when specifying target currency ${exchangeDetails.currency}`,
+    );
+  }
+
+  const withdrawalAccountList = await fetchWithdrawalAccountInfo(ws, {
+    exchangeDetails,
+    instructedAmount,
+  });
+
   logger.trace("updating withdrawal denoms");
   await updateWithdrawalDenoms(ws, exchangeBaseUrl);
+
   logger.trace("getting candidate denoms");
   const denoms = await getCandidateWithdrawalDenoms(ws, exchangeBaseUrl);
   logger.trace("selecting withdrawal denoms");
@@ -1773,8 +1794,15 @@ export async function getExchangeWithdrawalInfo(
   }
 
   const exchangeWireAccounts: string[] = [];
+
   for (const account of exchangeDetails.wireInfo.accounts) {
-    exchangeWireAccounts.push(account.payto_uri);
+    const details: WireAccountDetails = {
+      paytoUri: account.payto_uri,
+    };
+    if (account.credit_restrictions) {
+      details.creditRestrictions = account.credit_restrictions;
+    }
+    exchangeWireAccounts.push(details.paytoUri);
   }
 
   let hasDenomWithAgeRestriction = false;
@@ -1854,6 +1882,7 @@ export async function getExchangeWithdrawalInfo(
     earliestDepositExpiration,
     exchangePaytoUris: paytoUris,
     exchangeWireAccounts,
+    withdrawalAccountList,
     exchangeVersion: exchangeDetails.protocolVersionRange || "unknown",
     numOfferedDenoms: possibleDenoms.length,
     selectedDenoms,
@@ -1946,15 +1975,6 @@ export async function getWithdrawalDetailsForUri(
   };
 }
 
-export async function getFundingPaytoUrisTx(
-  ws: InternalWalletState,
-  withdrawalGroupId: string,
-): Promise<string[]> {
-  return await ws.db
-    .mktx((x) => [x.exchanges, x.exchangeDetails, x.withdrawalGroups])
-    .runReadWrite((tx) => getFundingPaytoUris(tx, withdrawalGroupId));
-}
-
 export function augmentPaytoUrisForWithdrawal(
   plainPaytoUris: string[],
   reservePub: string,
@@ -2361,10 +2381,6 @@ export async function internalPrepareCreateWithdrawalGroup(
 
   const exchangeInfo = await updateExchangeFromUrl(ws, canonExchange);
   const exchangeDetails = exchangeInfo.exchangeDetails;
-  if (!exchangeDetails) {
-    logger.trace(exchangeDetails);
-    throw Error("exchange not updated");
-  }
   const transactionId = constructTransactionIdentifier({
     tag: TransactionType.Withdrawal,
     withdrawalGroupId: withdrawalGroup.withdrawalGroupId,
@@ -2566,6 +2582,60 @@ export async function acceptWithdrawalFromUri(
 }
 
 /**
+ * Gather information about bank accounts that can be used for
+ * withdrawals.  This includes accounts that are in a different
+ * currency and require conversion.
+ */
+async function fetchWithdrawalAccountInfo(
+  ws: InternalWalletState,
+  req: {
+    exchangeDetails: ExchangeDetailsRecord;
+    instructedAmount: AmountJson;
+    reservePub?: string;
+  },
+): Promise<WithdrawalAccountInfo[]> {
+  const { exchangeDetails, instructedAmount } = req;
+  const withdrawalAccounts: WithdrawalAccountInfo[] = [];
+  for (let acct of exchangeDetails.wireInfo.accounts) {
+    let paytoUri: string;
+    let transferAmount: AmountString;
+    if (acct.conversion_url != null) {
+      const reqUrl = new URL("cashin-rate", acct.conversion_url);
+      reqUrl.searchParams.set(
+        "amount_credit",
+        Amounts.stringify(instructedAmount),
+      );
+      const httpResp = await ws.http.fetch(reqUrl.href);
+      const resp = await readSuccessResponseJsonOrThrow(
+        httpResp,
+        codecForCashinConversionResponse(),
+      );
+      paytoUri = acct.payto_uri;
+      transferAmount = resp.amount_debit;
+      if (req.reservePub) {
+      }
+    } else {
+      paytoUri = acct.payto_uri;
+      transferAmount = Amounts.stringify(instructedAmount);
+    }
+    paytoUri = addPaytoQueryParams(paytoUri, {
+      amount: Amounts.stringify(transferAmount),
+    });
+    if (req.reservePub != null) {
+      paytoUri = addPaytoQueryParams(paytoUri, {
+        message: `Taler Withdrawal ${req.reservePub}`,
+      });
+    }
+    const acctInfo: WithdrawalAccountInfo = {
+      paytoUri,
+      transferAmount,
+    };
+    withdrawalAccounts.push(acctInfo);
+  }
+  return withdrawalAccounts;
+}
+
+/**
  * Create a manual withdrawal operation.
  *
  * Adds the corresponding exchange as a trusted exchange if it is neither
@@ -2582,15 +2652,39 @@ export async function createManualWithdrawal(
     forcedDenomSel?: ForcedDenomSel;
   },
 ): Promise<AcceptManualWithdrawalResult> {
+  const { exchangeBaseUrl } = req;
+  const amount = Amounts.parseOrThrow(req.amount);
+  const { exchangeDetails } = await ws.exchangeOps.updateExchangeFromUrl(
+    ws,
+    exchangeBaseUrl,
+  );
+
+  if (exchangeDetails.currency != amount.currency) {
+    throw Error(
+      "manual withdrawal with conversion from foreign currency is not yet supported",
+    );
+  }
+  const reserveKeyPair: EddsaKeypair = await ws.cryptoApi.createEddsaKeypair(
+    {},
+  );
+
+  const withdrawalAccountList = await fetchWithdrawalAccountInfo(ws, {
+    exchangeDetails,
+    instructedAmount: amount,
+    reservePub: reserveKeyPair.pub,
+  });
+
   const withdrawalGroup = await internalCreateWithdrawalGroup(ws, {
     amount: Amounts.jsonifyAmount(req.amount),
     wgInfo: {
       withdrawalType: WithdrawalRecordType.BankManual,
+      exchangeCreditAccounts: withdrawalAccountList,
     },
     exchangeBaseUrl: req.exchangeBaseUrl,
     forcedDenomSel: req.forcedDenomSel,
     restrictAge: req.restrictAge,
     reserveStatus: WithdrawalGroupStatus.PendingQueryingStatus,
+    reserveKeyPair,
   });
 
   const withdrawalGroupId = withdrawalGroup.withdrawalGroupId;
@@ -2610,6 +2704,7 @@ export async function createManualWithdrawal(
   return {
     reservePub: withdrawalGroup.reservePub,
     exchangePaytoUris: exchangePaytoUris,
+    withdrawalAccountsList: withdrawalAccountList,
     transactionId,
   };
 }
diff --git a/packages/taler-wallet-core/src/wallet.ts b/packages/taler-wallet-core/src/wallet.ts
index 0694aef8a..4472bdbad 100644
--- a/packages/taler-wallet-core/src/wallet.ts
+++ b/packages/taler-wallet-core/src/wallet.ts
@@ -1215,6 +1215,7 @@ async function dispatchRequestInternal<Op extends WalletApiOperation>(
         paytoUris: wi.exchangePaytoUris,
         tosAccepted: wi.termsOfServiceAccepted,
         ageRestrictionOptions: wi.ageRestrictionOptions,
+        withdrawalAccountList: wi.withdrawalAccountList,
         numCoins,
       };
       return resp;