1 files changed, 68 insertions, 0 deletions
diff --git a/packages/taler-wallet-core/src/operations/currencies.ts b/packages/taler-wallet-core/src/operations/currencies.ts
new file mode 100644
index 000000000..1af30dfb5
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+++ b/packages/taler-wallet-core/src/operations/currencies.ts
@@ -0,0 +1,68 @@
+/*
+ This file is part of GNU Taler
+ (C) 2021 Taler Systems S.A.
+
+ GNU Taler is free software; you can redistribute it and/or modify it under the
+ terms of the GNU General Public License as published by the Free Software
+ Foundation; either version 3, or (at your option) any later version.
+
+ GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License along with
+ GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+/**
+ * Imports.
+ */
+import { ExchangeRecord, Stores } from "../db.js";
+import { Logger } from "../index.js";
+import { InternalWalletState } from "./state.js";
+
+const logger = new Logger("currencies.ts");
+
+export interface TrustInfo {
+  isTrusted: boolean;
+  isAudited: boolean;
+}
+
+/**
+ * Check if and how an exchange is trusted and/or audited.
+ */
+export async function getExchangeTrust(
+  ws: InternalWalletState,
+  exchangeInfo: ExchangeRecord,
+): Promise<TrustInfo> {
+  let isTrusted = false;
+  let isAudited = false;
+  const exchangeDetails = exchangeInfo.details;
+  if (!exchangeDetails) {
+    throw Error(`exchange ${exchangeInfo.baseUrl} details not available`);
+  }
+  const exchangeTrustRecord = await ws.db.getIndexed(
+    Stores.exchangeTrustStore.exchangeMasterPubIndex,
+    exchangeDetails.masterPublicKey,
+  );
+  if (
+    exchangeTrustRecord &&
+    exchangeTrustRecord.uids.length > 0 &&
+    exchangeTrustRecord.currency === exchangeDetails.currency
+  ) {
+    isTrusted = true;
+  }
+
+  for (const auditor of exchangeDetails.auditors) {
+    const auditorTrustRecord = await ws.db.getIndexed(
+      Stores.auditorTrustStore.auditorPubIndex,
+      auditor.auditor_pub,
+    );
+    if (auditorTrustRecord && auditorTrustRecord.uids.length > 0) {
+      isAudited = true;
+      break;
+    }
+  }
+
+  return { isTrusted, isAudited };
+}