fix: portfolio amount value

packages/espressocash_app/lib/features/authenticated/widgets/portfolio_widget.dart

@@ -11,7 +11,6 @@ import '../../../ui/value_stream_builder.dart';
 import '../../conversion_rates/services/token_fiat_balance_service.dart';
 import '../../conversion_rates/widgets/extensions.dart';
 import '../../currency/models/amount.dart';
-import '../../currency/models/currency.dart';
 import '../../tokens/widgets/token_icon.dart';
 
 class PortfolioWidget extends StatefulWidget {
@@ -71,26 +70,28 @@ class PortfolioTile extends StatelessWidget {
                     ),
                   ),
                   const SizedBox(width: 8),
-                  ValueStreamBuilder<Amount>(
+                  ValueStreamBuilder<Amount?>(
                     create: () => (
                       sl<TokenFiatBalanceService>()
                           .watchTotalInvestmentsBalance(),
-                      Amount.zero(currency: Currency.usd),
+                      null,
                     ),
-                    builder: (context, balance) => Flexible(
-                      child: FittedBox(
-                        child: Text(
-                          balance.format(DeviceLocale.localeOf(context)),
-                          style: Theme.of(context)
-                              .textTheme
-                              .displayMedium
-                              ?.copyWith(
-                                fontSize: 25,
-                                fontWeight: FontWeight.w600,
+                    builder: (context, balance) => balance != null
+                        ? Flexible(
+                            child: FittedBox(
+                              child: Text(
+                                balance.format(DeviceLocale.localeOf(context)),
+                                style: Theme.of(context)
+                                    .textTheme
+                                    .displayMedium
+                                    ?.copyWith(
+                                      fontSize: 25,
+                                      fontWeight: FontWeight.w600,
+                                    ),
                               ),
-                        ),
-                      ),
-                    ),
+                            ),
+                          )
+                        : const SizedBox.shrink(),
                   ),
                 ],
               ),
@@ -137,18 +138,15 @@ class _TokenItem extends StatelessWidget {
   });
 
   final CryptoAmount cryptoAmount;
-  final FiatAmount fiatAmount;
+  final FiatAmount? fiatAmount;
 
   static const double _iconSize = 36.0;
   static const double _minFiatAmount = 0.01;
 
   @override
   Widget build(BuildContext context) {
-    String fiatAmountText;
-
-    fiatAmountText = fiatAmount.value < _minFiatAmount
-        ? r'<$0.01'
-        : fiatAmount.format(context.locale, maxDecimals: 2);
+    final String fiatAmountText =
+        context.portfilioTotalAmountText(fiatAmount, _minFiatAmount);
 
     return _Card(
       child: ListTile(
@@ -214,3 +212,17 @@ class _Card extends StatelessWidget {
         child: child,
       );
 }
+
+extension TotalPortfolioTextExtension on BuildContext {
+  String portfilioTotalAmountText(FiatAmount? fiatAmount, num minFiatAmount) {
+    if (fiatAmount != null) {
+      if (fiatAmount.value < minFiatAmount) {
+        return r'<$0.01';
+      }
+
+      return fiatAmount.format(locale, maxDecimals: 2);
+    }
+
+    return '-';
+  }
+}

packages/espressocash_app/lib/features/conversion_rates/services/token_fiat_balance_service.dart

@@ -1,4 +1,3 @@
-import 'package:collection/collection.dart';
 import 'package:fast_immutable_collections/fast_immutable_collections.dart';
 import 'package:injectable/injectable.dart';
 import 'package:rxdart/rxdart.dart';
@@ -10,7 +9,7 @@ import '../../currency/models/currency.dart';
 import '../../tokens/token.dart';
 import '../data/repository.dart';
 
-typedef CryptoFiatAmount = (CryptoAmount, FiatAmount);
+typedef CryptoFiatAmount = (CryptoAmount, FiatAmount?);
 
 @injectable
 class TokenFiatBalanceService {
@@ -48,32 +47,48 @@ class TokenFiatBalanceService {
   Stream<FiatAmount> watchMainBalance() =>
       watch(Token.usdc).map((it) => it ?? _zeroFiat);
 
-  Stream<FiatAmount> watchTotalInvestmentsBalance() => _balancesRepository
+  Stream<FiatAmount?> watchTotalInvestmentsBalance() => _balancesRepository
       .watchUserTokens(ignoreTokens: [Token.usdc])
       .flatMap(
         (tokens) => Rx.combineLatest(
           tokens.map(watch),
-          (values) => values
-              .whereNotNull()
-              .fold(_zeroFiat, (total, next) => (total + next) as FiatAmount),
+          (values) => values.fold<FiatAmount?>(
+            null,
+            (total, next) {
+              if (next == null) return total;
+              if (total == null) return next;
+
+              return total + next as FiatAmount;
+            },
+          ),
         ),
       )
       .distinct()
-      .doOnData(_logTotalCryptoBalance);
+      .doOnData((total) {
+        if (total != null) {
+          _logTotalCryptoBalance(total);
+        }
+      });
 
   Stream<IList<CryptoFiatAmount>> watchInvestmentBalances() =>
       _balancesRepository
           .watchTokenBalances(ignoreTokens: [Token.usdc])
           .flatMap(
             (cryptoAmounts) => Rx.combineLatest(
               cryptoAmounts.map((c) => watch(c.token).map((fiat) => (c, fiat))),
-              (values) => values.map((e) => (e.$1, e.$2 ?? _zeroFiat)),
+              (values) => values.map((e) => (e.$1, e.$2)).toList(),
             ),
           )
           .map((amount) => amount.toIList())
           .map(
-            (amounts) =>
-                amounts.sort((a, b) => b.$2.value.compareTo(a.$2.value)),
+            (amounts) => amounts.sort(
+              (a, b) {
+                final aValue = a.$2?.value ?? 0;
+                final bValue = b.$2?.value ?? 0;
+
+                return bValue.compareTo(aValue);
+              },
+            ),
           )
           .distinct();