Show the balance in fiat again, priced from the 1Click listing

mobile-app/lib/providers/currency_display_provider.dart

@@ -1,3 +1,4 @@
+import 'dart:async';
 import 'dart:convert';
 
 import 'package:decimal/decimal.dart';
@@ -9,6 +10,7 @@ import 'package:resonance_network_wallet/providers/account_providers.dart';
 import 'package:resonance_network_wallet/providers/wallet_providers.dart';
 import 'package:resonance_network_wallet/services/exchange_rate_service.dart';
 import 'package:resonance_network_wallet/shared/utils/print.dart';
+import 'package:resonance_network_wallet/v2/screens/swap/swap_providers.dart';
 
 // ---------------------------------------------------------------------------
 // Exchange rate caching helpers
@@ -109,6 +111,38 @@ final exchangeRatesProvider = FutureProvider<Map<String, Decimal>>((ref) async {
   }
 });
 
+// ---------------------------------------------------------------------------
+// Token price provider
+// ---------------------------------------------------------------------------
+
+/// How often 1Click is asked for QTC's price; an unchanged listing costs a 304.
+const tokenPriceRefreshInterval = Duration(minutes: 5);
+
+/// QTC's USD price as 1Click lists it, refreshed every
+/// [tokenPriceRefreshInterval]. A failed refresh is logged and the last price
+/// stands; there is none until the first lands.
+final tokenUsdPriceProvider = StreamProvider<Decimal>((ref) {
+  final swap = ref.watch(swapServiceProvider);
+  final prices = StreamController<Decimal>();
+
+  Future<void> refresh() async {
+    try {
+      final listed = await swap.getListedQuantusToken(forceRefresh: true);
+      if (listed != null && !prices.isClosed) prices.add(Decimal.parse(listed.usdPrice.toString()));
+    } catch (e) {
+      quantusPrint('QTC price refresh failed: $e');
+    }
+  }
+
+  final timer = Timer.periodic(tokenPriceRefreshInterval, (_) => refresh());
+  ref.onDispose(() {
+    timer.cancel();
+    prices.close();
+  });
+  unawaited(refresh());
+  return prices.stream;
+});
+
 // ---------------------------------------------------------------------------
 // Exchange rate service provider
 // ---------------------------------------------------------------------------
@@ -118,14 +152,19 @@ final exchangeRatesProvider = FutureProvider<Map<String, Decimal>>((ref) async {
 /// • While [exchangeRatesProvider] is loading, uses the last persisted rates
 ///   (any age) so the UI always shows something meaningful.
 /// • Once live rates arrive, rebuilds with the fresh data.
+/// • Carries QTC's USD price once [tokenUsdPriceProvider] has one.
 final exchangeRateServiceProvider = Provider<ExchangeRateService>((ref) {
   final ratesAsync = ref.watch(exchangeRatesProvider);
   final settings = ref.read(settingsServiceProvider);
+  final tokenToUsdRate = ref.watch(tokenUsdPriceProvider).value;
+
+  ExchangeRateService service(Map<String, Decimal> rates) =>
+      ExchangeRateService(rates: rates, tokenToUsdRate: tokenToUsdRate);
 
   return ratesAsync.when(
-    data: (rates) => ExchangeRateService(rates: rates),
-    loading: () => ExchangeRateService(rates: _readRatesCacheAnyAge(settings)),
-    error: (_, _) => ExchangeRateService(rates: _readRatesCacheAnyAge(settings)),
+    data: service,
+    loading: () => service(_readRatesCacheAnyAge(settings)),
+    error: (_, _) => service(_readRatesCacheAnyAge(settings)),
   );
 });
 
@@ -178,10 +217,12 @@ class SelectedFiatCurrencyNotifier extends StateNotifier<FiatCurrency> {
 /// No conversion math belongs in widgets.
 class CurrencyDisplayState {
   final String primaryAmount;
-  final String secondaryAmount;
+
+  /// The amount in [selectedFiat]; null when it is not to be shown or no token price is known.
+  final String? secondaryAmount;
   final FiatCurrency selectedFiat;
 
-  const CurrencyDisplayState({required this.primaryAmount, required this.secondaryAmount, required this.selectedFiat});
+  const CurrencyDisplayState({required this.primaryAmount, this.secondaryAmount, required this.selectedFiat});
 
   CurrencyDisplayState copyWith({String? primaryAmount, String? secondaryAmount, FiatCurrency? selectedFiat}) =>
       CurrencyDisplayState(
@@ -214,18 +255,17 @@ final balanceDisplayProvider = Provider<AsyncValue<CurrencyDisplayState>>((ref)
   return balanceAsync.when(
     loading: () => const AsyncValue.loading(),
     error: (err, stack) => AsyncValue.error(err, stack),
-    data: (balance) {
-      CurrencyDisplayState data = _toFiatDisplayState(
+    data: (balance) => AsyncValue.data(
+      _toFiatDisplayState(
         balance,
         selectedFiat,
-        xRate,
         fmt,
         tokenDecimals: 3,
         withTokenSymbol: false,
         localeConfig: localeConfig,
-      );
-      return AsyncValue.data(data);
-    },
+        fiatRate: xRate,
+      ),
+    ),
   );
 });
 
@@ -244,7 +284,6 @@ typedef TxAmountFormatter =
 
 final txAmountDisplayProvider = Provider<TxAmountFormatter>((ref) {
   final selectedFiat = ref.watch(selectedFiatCurrencyProvider);
-  final xRate = ref.watch(exchangeRateServiceProvider);
   final fmt = ref.watch(numberFormattingServiceProvider);
   final localeConfig = ref.watch(localeNumberConfigProvider);
 
@@ -260,7 +299,6 @@ final txAmountDisplayProvider = Provider<TxAmountFormatter>((ref) {
     CurrencyDisplayState data = _toFiatDisplayState(
       amount,
       selectedFiat,
-      xRate,
       fmt,
       tokenDecimals: tokenDecimals,
       withTokenSymbol: withTokenSymbol,
@@ -294,21 +332,24 @@ String _toFiatNumeric(
   return localeConfig.localize(canonical);
 }
 
+/// [fiatRate] adds the fiat amount; it stays out while no token price is known.
 CurrencyDisplayState _toFiatDisplayState(
   BigInt amount,
   FiatCurrency selectedFiat,
-  ExchangeRateService xRate,
   NumberFormattingService fmt, {
   required int tokenDecimals,
   required bool withTokenSymbol,
   required LocaleNumberConfig localeConfig,
+  ExchangeRateService? fiatRate,
 }) {
   final tokenFormatted = fmt.formatBalance(amount, smartDecimals: tokenDecimals, addSymbol: withTokenSymbol);
-  final fiatFormatted = selectedFiat.format(_toFiatNumeric(amount, selectedFiat, xRate, localeConfig: localeConfig));
+  final withFiat = fiatRate != null && fiatRate.hasTokenPrice;
 
   return CurrencyDisplayState(
     primaryAmount: tokenFormatted,
-    secondaryAmount: fiatFormatted,
+    secondaryAmount: withFiat
+        ? selectedFiat.format(_toFiatNumeric(amount, selectedFiat, fiatRate, localeConfig: localeConfig))
+        : null,
     selectedFiat: selectedFiat,
   );
 }

mobile-app/lib/services/exchange_rate_service.dart

@@ -6,8 +6,8 @@ import 'package:resonance_network_wallet/models/fiat_currency.dart';
 /// Constructed with a live [rates] map (ISO-4217 code → value in that currency
 /// per 1 USD). Falls back to [fallbackRates] for any code not present.
 ///
-/// [tokenToUsdRate] defaults to `1` (1 token = 1 USD). Wire a dedicated tokens
-/// price feed into this field when one becomes available.
+/// [tokenToUsdRate] is the token's USD price, null while none is known;
+/// converting without one throws.
 class ExchangeRateService {
   /// Static rates used before any live or cached data is available (e.g. on
   /// fresh install with no network). Values are approximate and intentionally
@@ -23,11 +23,13 @@ class ExchangeRateService {
   };
 
   final Map<String, Decimal> _rates;
-  final Decimal tokenToUsdRate;
+  final Decimal? tokenToUsdRate;
 
-  ExchangeRateService({required Map<String, Decimal> rates, Decimal? tokenToUsdRate})
-    : _rates = rates,
-      tokenToUsdRate = tokenToUsdRate ?? Decimal.one;
+  ExchangeRateService({required Map<String, Decimal> rates, this.tokenToUsdRate}) : _rates = rates;
+
+  bool get hasTokenPrice => tokenToUsdRate != null;
+
+  Decimal get _tokenPrice => tokenToUsdRate ?? (throw StateError('Token price unknown'));
 
   /// Returns the exchange rate for [fiat] (units per 1 USD).
   Decimal getRate(FiatCurrency fiat) {
@@ -39,7 +41,7 @@ class ExchangeRateService {
 
   /// Converts [tokenAmount] to [fiat] using the current rates.
   Decimal convert(Decimal tokenAmount, FiatCurrency fiat) {
-    final result = (tokenAmount * tokenToUsdRate * getRate(fiat));
+    final result = (tokenAmount * _tokenPrice * getRate(fiat));
     // Round to fiat precision to ensure stable round-trips
     return Decimal.parse(result.toStringAsFixed(fiat.decimals));
   }
@@ -59,7 +61,7 @@ class ExchangeRateService {
   /// Uses the inverse of [convert]: fiat / (tokenToUsdRate × rate).
   /// Returns [BigInt.zero] when the effective rate is zero.
   BigInt fiatToToken(Decimal fiatAmount, FiatCurrency fiat, int tokenDecimals) {
-    final effectiveRate = tokenToUsdRate * getRate(fiat);
+    final effectiveRate = _tokenPrice * getRate(fiat);
     if (effectiveRate == Decimal.zero) return BigInt.zero;
     final scaleFactor = Decimal.fromBigInt(BigInt.from(10).pow(tokenDecimals));
     final tokenDecimal = (fiatAmount / effectiveRate).toDecimal(scaleOnInfinitePrecision: tokenDecimals);

mobile-app/lib/v2/components/amount_display_with_conversion.dart

@@ -13,7 +13,7 @@ class AmountDisplayWithConversion extends StatelessWidget {
   final Color? amountColor;
   final bool useTokenLogo;
 
-  /// Masks the amount with [hiddenAmountText]. Owned by the screen that
+  /// Masks the amounts with [hiddenAmountText]. Owned by the screen that
   /// offers the hide toggle — never read from a global setting here.
   final bool isHidden;
 
@@ -36,41 +36,55 @@ class AmountDisplayWithConversion extends StatelessWidget {
     const tokenLogoPrimarySize = 32.0;
 
     final primaryAmount = isHidden ? hiddenAmountText : amountDisplay.primaryAmount;
+    final secondaryAmount = amountDisplay.secondaryAmount;
 
     final MainAxisAlignment mainAxisAlignment = switch (alignment) {
       CrossAxisAlignment.center => MainAxisAlignment.center,
       _ => MainAxisAlignment.start,
     };
 
-    return Row(
-      mainAxisAlignment: mainAxisAlignment,
+    return Column(
+      mainAxisSize: MainAxisSize.min,
+      crossAxisAlignment: alignment,
       children: [
-        if (useTokenLogo) ...[
-          SvgPicture.asset(
-            'assets/v2/uppercase_q.svg',
-            width: tokenLogoPrimarySize,
-            height: tokenLogoPrimarySize,
-            colorFilter: ColorFilter.mode(colors.textContent, BlendMode.srcIn),
-          ),
-          const SizedBox(width: 4),
-        ],
-        Text.rich(
-          TextSpan(
-            children: [
-              TextSpan(
-                text: primaryAmount,
-                style: text.displayBalance.copyWith(color: primaryAmountColor),
+        Row(
+          mainAxisAlignment: mainAxisAlignment,
+          children: [
+            if (useTokenLogo) ...[
+              SvgPicture.asset(
+                'assets/v2/uppercase_q.svg',
+                width: tokenLogoPrimarySize,
+                height: tokenLogoPrimarySize,
+                colorFilter: ColorFilter.mode(colors.textContent, BlendMode.srcIn),
               ),
-              if (!useTokenLogo) ...[
-                const TextSpan(text: ' '),
-                TextSpan(
-                  text: AppConstants.tokenSymbol,
-                  style: text.amountHero.copyWith(color: primaryAmountColor),
-                ),
-              ],
+              const SizedBox(width: 4),
             ],
-          ),
+            Text.rich(
+              TextSpan(
+                children: [
+                  TextSpan(
+                    text: primaryAmount,
+                    style: text.displayBalance.copyWith(color: primaryAmountColor),
+                  ),
+                  if (!useTokenLogo) ...[
+                    const TextSpan(text: ' '),
+                    TextSpan(
+                      text: AppConstants.tokenSymbol,
+                      style: text.amountHero.copyWith(color: primaryAmountColor),
+                    ),
+                  ],
+                ],
+              ),
+            ),
+          ],
         ),
+        if (secondaryAmount != null) ...[
+          const SizedBox(height: 8),
+          Text(
+            '≈ ${isHidden ? hiddenAmountText : secondaryAmount}',
+            style: text.body.copyWith(color: colors.textMuted),
+          ),
+        ],
       ],
     );
   }

mobile-app/lib/v2/components/token_icon.dart

@@ -15,8 +15,6 @@ class TokenIcon extends StatelessWidget {
   Widget build(BuildContext context) {
     final colors = context.colorsV3;
     final text = context.themeTextV3;
-    final iconUrl = token.iconUrl;
-    final networkIconUrl = token.networkIconUrl;
 
     if (token.isQuantus) {
       return Container(
@@ -34,36 +32,22 @@ class TokenIcon extends StatelessWidget {
       child: Stack(
         clipBehavior: Clip.none,
         children: [
-          Positioned.fill(
-            child: ClipOval(
-              child: iconUrl != null
-                  ? Image.network(iconUrl, fit: BoxFit.cover, errorBuilder: (_, _, _) => _fallback(token, colors, text))
-                  : _fallback(token, colors, text),
-            ),
-          ),
+          Positioned.fill(child: _monogram(token, colors, text)),
           Positioned(
             right: -2,
             bottom: -2,
             child: SizedBox(
               width: networkBadgeSize,
               height: networkBadgeSize,
-              child: ClipOval(
-                child: networkIconUrl != null
-                    ? Image.network(
-                        networkIconUrl,
-                        fit: BoxFit.cover,
-                        errorBuilder: (_, _, _) => _networkFallback(token, colors, text),
-                      )
-                    : _networkFallback(token, colors, text),
-              ),
+              child: _networkMonogram(token, colors, text),
             ),
           ),
         ],
       ),
     );
   }
 
-  Widget _fallback(SwapToken token, AppColorsV3 colors, AppTextThemeV3 text) {
+  Widget _monogram(SwapToken token, AppColorsV3 colors, AppTextThemeV3 text) {
     return Container(
       decoration: BoxDecoration(
         color: colors.bgSurface2,
@@ -81,7 +65,7 @@ class TokenIcon extends StatelessWidget {
     );
   }
 
-  Widget _networkFallback(SwapToken token, AppColorsV3 colors, AppTextThemeV3 text) {
+  Widget _networkMonogram(SwapToken token, AppColorsV3 colors, AppTextThemeV3 text) {
     return Container(
       decoration: BoxDecoration(
         color: colors.bgVoid,

mobile-app/lib/v2/screens/swap/swap_screen.dart

@@ -74,7 +74,7 @@ class _SwapScreenState extends ConsumerState<SwapScreen> {
       final quantus = await service.getListedQuantusToken();
       if (!mounted || load != _loads) return;
       setState(() {
-        _foreign ??= tokens.first;
+        _foreign ??= tokens.firstWhere((t) => !t.isQuantus);
         _quantus = quantus;
       });
     } catch (e) {
@@ -95,18 +95,18 @@ class _SwapScreenState extends ConsumerState<SwapScreen> {
     _amountController.clear();
   }
 
-  /// Picks the external token. Picking from the QTC side moves QTC to the other side.
+  /// Picks a side's token. QTC heads the list: picking it for the other side
+  /// moves QTC there, as does picking a foreign token for QTC's side.
   Future<void> _pickToken(SwapToken tapped) async {
     final service = ref.read(swapServiceProvider);
-    final foreign = _foreign!;
     final token = await showTokenPickerSheet(
       context,
-      current: foreign,
+      current: tapped,
       loadTokens: ({bool forceRefresh = false}) => service.getFromTokens(limit: 10, forceRefresh: forceRefresh),
     );
-    if (token == null || !mounted) return;
-    setState(() => _foreign = token);
-    if (tapped.isQuantus) _setDirection(swapOut: !_swapOut);
+    if (token == null || !mounted || token == tapped) return;
+    if (!token.isQuantus) setState(() => _foreign = token);
+    if (token.isQuantus != tapped.isQuantus) _setDirection(swapOut: !_swapOut);
   }
 
   /// The sheet quotes with the service of the moment, so a config change

mobile-app/test/unit/amount_input_logic_test.dart

@@ -12,7 +12,7 @@ void main() {
     late NumberFormattingService formattingService;
 
     setUp(() {
-      exchangeRateService = ExchangeRateService(rates: {'USD': Decimal.one});
+      exchangeRateService = ExchangeRateService(rates: {'USD': Decimal.one}, tokenToUsdRate: Decimal.one);
       localeConfig = LocaleNumberConfig.dotDecimal;
       formattingService = NumberFormattingService(localeConfig: localeConfig);
     });