chore: fiat store updateExchange accept fiat currency as input

src/main.ts

@@ -60,7 +60,7 @@ async function start() {
     function queueExchangeRateUpdate() {
         setTimeout(async () => {
             exchangeRateUpdateStart = Date.now(); // in contrast to fiatStore.timestamp set before the update
-            await updateExchangeRates(/* failGracefully */ true); // silently ignores errors
+            await updateExchangeRates({ failGracefully: true }); // silently ignores errors
             queueExchangeRateUpdate();
         // Also add 2 minutes as upper bound to be immune to the user's system clock being wrong.
         }, Math.max(0, Math.min(exchangeRateUpdateStart + TWO_MINUTES - Date.now(), TWO_MINUTES)));

src/stores/Fiat.ts

@@ -66,6 +66,16 @@ export function guessUserCurrency(regionOverwrite?: string) {
     return FiatCurrency.USD;
 }
 
+export type UpdateExchangeRatesOptions = {
+    // The currency to load
+    // @default this.state.currency
+    fiatCurrency?: FiatCurrencyOffered,
+
+    // If true, the function will not throw an error if the exchange rate update fails.
+    // @default true
+    failGracefully?: boolean,
+}
+
 export const useFiatStore = createStore({
     id: 'fiat',
     state: (): FiatState => ({
@@ -86,21 +96,21 @@ export const useFiatStore = createStore({
             useBtcTransactionsStore().calculateFiatAmounts();
             useUsdcTransactionsStore().calculateFiatAmounts();
         },
-        async updateExchangeRates(failGracefully = true) {
+        async updateExchangeRates(options: UpdateExchangeRatesOptions = {}) {
+            const { failGracefully = true, fiatCurrency = this.state.currency } = options;
             try {
-                const currentCurrency = this.state.currency;
                 // If a currency is bridged, but not by a bridge that supports historic rates, it's bridged via CPL Api.
                 const isCplBridgedFiatCurrency = (currency: FiatCurrency) => isBridgedFiatCurrency(
                     currency,
                     FIAT_API_PROVIDER_CURRENT_PRICES,
                     RateType.CURRENT,
                 ) && !isHistorySupportedFiatCurrency(currency, FIAT_API_PROVIDER_CURRENT_PRICES);
-                const isCurrentCurrencyCplBridged = isCplBridgedFiatCurrency(currentCurrency);
+                const isCurrentCurrencyCplBridged = isCplBridgedFiatCurrency(fiatCurrency);
                 const prioritizedFiatCurrenciesOffered: Array<FiatCurrencyOffered> = [...new Set<FiatCurrencyOffered>([
                     // As we limit the currencies we fetch for CryptoCompare to 25, prioritize a few currencies, we'd
                     // prefer to be included, roughly the highest market cap currencies according to fiatmarketcap.com,
                     // plus some smaller currencies for which Nimiq has strong communities.
-                    currentCurrency,
+                    fiatCurrency,
                     ...(['USD', 'CNY', 'EUR', 'JPY', 'GBP', 'KRW', 'INR', 'CAD', 'HKD', 'BRL', 'AUD', 'CRC', 'GMD',
                         'XOF'] as const).map((ticker) => FiatCurrency[ticker]),
                     // After that, prefer to include currencies CryptoCompare supports historic rates for, because it is
@@ -116,7 +126,7 @@ export const useFiatStore = createStore({
                 ])];
                 const currenciesToUpdate: Array<FiatCurrencyOffered> = [];
                 for (const currency of prioritizedFiatCurrenciesOffered) {
-                    if (currency !== currentCurrency
+                    if (currency !== fiatCurrency
                         // Include all provider supported currencies, as at least one always has to be fetched via the
                         // provider api, either because it's a directly supported currency, or because it's a currency
                         // bridged via USD, also fetched from the provider, and fetching multiple currencies vs. only