Re: pos mode update

mobile-app/lib/shared/utils/amount_input_logic.dart

@@ -0,0 +1,88 @@
+import 'package:quantus_sdk/quantus_sdk.dart';
+import 'package:resonance_network_wallet/models/fiat_currency.dart';
+import 'package:resonance_network_wallet/services/exchange_rate_service.dart';
+
+class ToggledInputResult {
+  final String text;
+  final BigInt amount;
+
+  ToggledInputResult({required this.text, required this.amount});
+
+  @override
+  bool operator ==(Object other) =>
+      identical(this, other) ||
+      other is ToggledInputResult && runtimeType == other.runtimeType && text == other.text && amount == other.amount;
+
+  @override
+  int get hashCode => text.hashCode ^ amount.hashCode;
+}
+
+class AmountInputLogic {
+  final ExchangeRateService exchangeRateService;
+  final FiatCurrency selectedFiat;
+  final LocaleNumberConfig localeConfig;
+  final NumberFormattingService formattingService;
+
+  AmountInputLogic({
+    required this.exchangeRateService,
+    required this.selectedFiat,
+    required this.localeConfig,
+    required this.formattingService,
+  });
+
+  /// Converts a raw QUAN [BigInt] to a fiat input string using the current
+  /// exchange rate and selected fiat currency, formatted for the user's locale.
+  String quanToFiatString(BigInt quanAmount) {
+    if (quanAmount == BigInt.zero) return '';
+    final fiatValue = exchangeRateService.quanRawToFiat(quanAmount, selectedFiat, AppConstants.decimals);
+    final canonical = fiatValue.toStringAsFixed(selectedFiat.decimals);
+    return localeConfig.localize(canonical, addGroupingSeparators: false);
+  }
+
+  /// Parses a locale-formatted fiat input string and returns the equivalent
+  /// raw QUAN [BigInt] scaled by [AppConstants.decimals].
+  ///
+  /// Throws [InvalidNumberInputException] when [fiatText] cannot be parsed.
+  BigInt fiatStringToQuan(String fiatText) {
+    if (fiatText.isEmpty) return BigInt.zero;
+    final fiatDecimal = localeConfig.parseDecimal(fiatText);
+    return exchangeRateService.fiatToQuanRaw(fiatDecimal, selectedFiat, AppConstants.decimals);
+  }
+
+  /// Parses a QUAN amount string.
+  BigInt parseQuanAmount(String text) {
+    if (text.isEmpty) return BigInt.zero;
+    return formattingService.parseAmount(text) ?? BigInt.zero;
+  }
+
+  /// Formats a QUAN amount for display in an input field.
+  String formatQuanAmount(BigInt amount) {
+    if (amount == BigInt.zero) return '';
+    return formattingService.formatBalance(amount, maxDecimals: AppConstants.decimals, addThousandsSeparators: false);
+  }
+
+  /// Returns the new input string and amount when toggling between QUAN and Fiat.
+  ToggledInputResult getToggledInput({required bool wasFlipped, required BigInt currentAmount}) {
+    if (wasFlipped) {
+      // Fiat -> QUAN: The user was looking at a fiat amount.
+      // We already have currentAmount which was calculated from that fiat amount.
+      final text = formatQuanAmount(currentAmount);
+      return ToggledInputResult(text: text, amount: currentAmount);
+    } else {
+      // QUAN -> Fiat: re-parse amount from the rounded fiat string so
+      // the displayed value and amount stay in sync.
+      final text = quanToFiatString(currentAmount);
+      final newAmount = currentAmount == BigInt.zero ? BigInt.zero : fiatStringToQuan(text);
+      return ToggledInputResult(text: text, amount: newAmount);
+    }
+  }
+
+  /// Handles amount change and returns the updated BigInt amount.
+  BigInt onAmountChanged({required String value, required bool isFlipped}) {
+    if (isFlipped) {
+      return fiatStringToQuan(value);
+    } else {
+      return parseQuanAmount(value);
+    }
+  }
+}

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

@@ -0,0 +1,35 @@
+import 'package:flutter/material.dart';
+import 'package:qr_flutter/qr_flutter.dart';
+import 'package:resonance_network_wallet/v2/theme/app_colors.dart';
+
+class QuantusQr extends StatelessWidget {
+  final String accountId;
+
+  const QuantusQr({super.key, required this.accountId});
+
+  @override
+  Widget build(BuildContext context) {
+    final qrSize = 267.0;
+    final qrLogoSize = 64.0;
+
+    return Container(
+      decoration: BoxDecoration(
+        border: Border.all(color: context.colors.textTertiary, width: 1),
+        borderRadius: BorderRadius.circular(16),
+      ),
+      width: qrSize,
+      height: qrSize,
+      child: QrImageView(
+        data: accountId,
+        errorCorrectionLevel: QrErrorCorrectLevel.M,
+        embeddedImage: const AssetImage('assets/v2/uppercase_q_black_bg.png'),
+        embeddedImageStyle: QrEmbeddedImageStyle(size: Size(qrLogoSize, qrLogoSize)),
+        version: QrVersions.auto,
+        size: qrSize,
+        padding: const EdgeInsets.all(16),
+        eyeStyle: const QrEyeStyle(eyeShape: QrEyeShape.square, color: Colors.white),
+        dataModuleStyle: const QrDataModuleStyle(dataModuleShape: QrDataModuleShape.square, color: Colors.white),
+      ),
+    );
+  }
+}

mobile-app/lib/v2/screens/home/home_screen.dart

@@ -88,14 +88,12 @@ class _HomeScreenState extends ConsumerState<HomeScreen> {
       showSharedAddressActionSheet(context, shared);
     });
 
-    final isPosMode = ref.watch(posModeProvider);
-    final balanceAsync = ref.watch(balanceProvider);
     final accountAsync = ref.watch(activeAccountProvider);
     final txAsync = ref.watch(activeAccountTransactionsProvider(TransactionFilter.all));
     final colors = context.colors;
     final text = context.themeText;
 
-    Widget screen = accountAsync.when(
+    return accountAsync.when(
       loading: () => const ScaffoldBase(mainContent: Center(child: Loader())),
       error: (e, _) => ScaffoldBase(
         mainContent: Center(
@@ -111,46 +109,12 @@ class _HomeScreenState extends ConsumerState<HomeScreen> {
           slivers: [
             _buildContent(active, colors, text),
             ActivitySection(txAsync: txAsync, activeAccount: active.account, onRetry: _refresh),
-            SizedBox(height: isPosMode ? 120 : 58),
+            const SizedBox(height: 58),
           ],
-          bottomContent: balanceAsync
-              .whenData(
-                (balance) => balance == BigInt.zero
-                    ? ScaffoldBaseBottomContent(
-                        child: QuantusButton.simple(
-                          label: 'Get Testnet Tokens ↗',
-                          onTap: () => launchXPost(AppConstants.faucetUrl),
-                        ),
-                      )
-                    : null,
-              )
-              .value,
+          bottomContent: _buildBottomContent(),
         );
       },
     );
-
-    if (!isPosMode) return screen;
-
-    return Stack(
-      children: [
-        screen,
-        Positioned(
-          left: 24,
-          right: 24,
-          bottom: MediaQuery.of(context).padding.bottom + 24,
-          child: Material(color: Colors.transparent, child: _buildPosButton(colors, text)),
-        ),
-      ],
-    );
-  }
-
-  Widget _buildPosButton(AppColorsV2 colors, AppTextTheme text) {
-    return QuantusButton.simple(
-      label: 'New Charge',
-      variant: ButtonVariant.success,
-      onTap: () => Navigator.push(context, MaterialPageRoute(builder: (_) => const PosAmountScreen())),
-      textStyle: text.smallTitle?.copyWith(fontWeight: FontWeight.w700, fontSize: 20, decoration: TextDecoration.none),
-    );
   }
 
   Widget _buildContent(DisplayAccount active, AppColorsV2 colors, AppTextTheme text) {
@@ -173,6 +137,33 @@ class _HomeScreenState extends ConsumerState<HomeScreen> {
     );
   }
 
+  Widget? _buildBottomContent() {
+    final enablePos = ref.watch(posModeProvider);
+    final balanceAsync = ref.watch(balanceProvider);
+
+    if (enablePos) {
+      return ScaffoldBaseBottomContent(
+        child: QuantusButton.simple(
+          label: 'Charge',
+          onTap: () => Navigator.push(context, MaterialPageRoute(builder: (_) => const PosAmountScreen())),
+        ),
+      );
+    }
+
+    return balanceAsync
+        .whenData(
+          (balance) => balance == BigInt.zero
+              ? ScaffoldBaseBottomContent(
+                  child: QuantusButton.simple(
+                    label: 'Get Testnet Tokens ↗',
+                    onTap: () => launchXPost(AppConstants.faucetUrl),
+                  ),
+                )
+              : null,
+        )
+        .value;
+  }
+
   Widget _buildTopBar() {
     final isBalanceHidden = ref.watch(isBalanceHiddenProvider);
 
@@ -247,43 +238,37 @@ class _HomeScreenState extends ConsumerState<HomeScreen> {
       onTap: () => Navigator.push(context, MaterialPageRoute(builder: (_) => const SelectRecipientScreen())),
     );
 
-    if (!enableSwap) {
-      return Row(
-        mainAxisAlignment: MainAxisAlignment.center,
-        children: [
-          SizedBox(width: 151, child: receiveCard),
-          const SizedBox(width: 20),
-          SizedBox(width: 151, child: sendCard),
-        ],
-      );
+    final swapCard = _actionCard(
+      iconAsset: 'assets/v2/action_swap.svg',
+      label: 'Swap',
+      onTap: () => Navigator.push(context, MaterialPageRoute(builder: (_) => const SwapScreen())),
+    );
+
+    final List<Widget> children = [];
+
+    children.add(receiveCard);
+    children.add(const SizedBox(width: 15));
+    children.add(sendCard);
+
+    if (enableSwap) {
+      children.add(const SizedBox(width: 15));
+      children.add(swapCard);
     }
 
-    return Row(
-      children: [
-        Expanded(child: receiveCard),
-        const SizedBox(width: 15),
-        Expanded(child: sendCard),
-        const SizedBox(width: 15),
-        Expanded(
-          child: _actionCard(
-            iconAsset: 'assets/v2/action_swap.svg',
-            label: 'Swap',
-            onTap: () => Navigator.push(context, MaterialPageRoute(builder: (_) => const SwapScreen())),
-          ),
-        ),
-      ],
-    );
+    return Row(children: children);
   }
 
   Widget _actionCard({required String iconAsset, required String label, required VoidCallback onTap}) {
-    return QuantusButton.simple(
-      label: label,
-      onTap: onTap,
-      icon: SvgPicture.asset(iconAsset, width: 24, height: 24),
-      iconPlacement: IconPlacement.top,
-      padding: const EdgeInsets.all(14),
-      variant: ButtonVariant.secondary,
-      textStyle: context.themeText.paragraph?.copyWith(color: context.colors.textPrimary.useOpacity(0.8)),
+    return Expanded(
+      child: QuantusButton.simple(
+        label: label,
+        onTap: onTap,
+        icon: SvgPicture.asset(iconAsset, width: 24, height: 24),
+        iconPlacement: IconPlacement.top,
+        padding: const EdgeInsets.all(14),
+        variant: ButtonVariant.secondary,
+        textStyle: context.themeText.paragraph?.copyWith(color: context.colors.textPrimary.useOpacity(0.8)),
+      ),
     );
   }
 }