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diff --git a/packages/taler-wallet-webextension/src/hooks/useSelectedExchange.ts b/packages/taler-wallet-webextension/src/hooks/useSelectedExchange.ts
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+++ b/packages/taler-wallet-webextension/src/hooks/useSelectedExchange.ts
@@ -0,0 +1,125 @@
+/*
+ This file is part of GNU Taler
+ (C) 2022 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/>
+ */
+
+import { ExchangeListItem } from "@gnu-taler/taler-util";
+import { useState } from "preact/hooks";
+import { ButtonHandler } from "../mui/handlers.js";
+
+type State = State.Ready | State.NoExchange | State.Selecting;
+
+export namespace State {
+  export interface NoExchange {
+    status: "no-exchange"
+    error: undefined;
+  }
+  export interface Ready {
+    status: "ready",
+    doSelect: ButtonHandler,
+    selected: ExchangeListItem;
+  }
+  export interface Selecting {
+    status: "selecting-exchange",
+    error: undefined,
+    onSelection: (url: string) => Promise<void>;
+    onCancel: () => Promise<void>;
+    list: ExchangeListItem[],
+    currency: string;
+    currentExchange: string;
+  }
+}
+
+interface Props {
+  currency: string;
+  //there is a preference for the default at the initial state
+  defaultExchange?: string,
+  //list of exchanges
+  list: ExchangeListItem[],
+}
+
+
+
+export function useSelectedExchange({ currency, defaultExchange, list }: Props): State {
+  const [isSelecting, setIsSelecting] = useState(false);
+  const [selectedExchange, setSelectedExchange] = useState<string | undefined>(undefined);
+
+  if (!list.length) {
+    return {
+      status: "no-exchange",
+      error: undefined,
+    }
+  }
+
+  const firstByCurrency = list.find((e) => e.currency === currency)
+  if (!firstByCurrency) {
+    // there should be at least one exchange for this currency
+    return {
+      status: "no-exchange",
+      error: undefined,
+    }
+  }
+
+
+  if (isSelecting) {
+    const currentExchange = selectedExchange ?? defaultExchange ?? firstByCurrency.exchangeBaseUrl;
+    return {
+      status: "selecting-exchange",
+      error: undefined,
+      list,
+      currency,
+      currentExchange: currentExchange,
+      onSelection: async (exchangeBaseUrl: string) => {
+        setIsSelecting(false);
+        setSelectedExchange(exchangeBaseUrl)
+      },
+      onCancel: async () => {
+        setIsSelecting(false);
+      }
+    }
+  }
+
+  {
+    const found = !selectedExchange ? undefined : list.find(
+      (e) => e.exchangeBaseUrl === selectedExchange,
+    )
+    if (found) return {
+      status: "ready",
+      doSelect: {
+        onClick: async () => setIsSelecting(true)
+      },
+      selected: found
+    };
+  }
+  {
+    const found = !defaultExchange ? undefined : list.find(
+      (e) => e.exchangeBaseUrl === defaultExchange,
+    )
+    if (found) return {
+      status: "ready",
+      doSelect: {
+        onClick: async () => setIsSelecting(true)
+      },
+      selected: found
+    };
+  }
+
+  return {
+    status: "ready",
+    doSelect: {
+      onClick: async () => setIsSelecting(true)
+    },
+    selected: firstByCurrency
+  }
+}