changed color theme to be black and added the ability to enter the amount in the recipient’s currency

frontend/pshared/lib/provider/payment/amount.dart

@@ -1,12 +1,15 @@
 import 'package:flutter/material.dart';
 
+import 'package:pshared/models/payment/settlement_mode.dart';
 
 class PaymentAmountProvider with ChangeNotifier {
   double _amount = 10.0;
   bool _payerCoversFee = true;
+  SettlementMode _settlementMode = SettlementMode.fixSource;
 
   double get amount => _amount;
   bool get payerCoversFee => _payerCoversFee;
+  SettlementMode get settlementMode => _settlementMode;
 
   void setAmount(double value) {
     _amount = value;
@@ -17,4 +20,10 @@ class PaymentAmountProvider with ChangeNotifier {
     _payerCoversFee = value;
     notifyListeners();
   }
+
+  void setSettlementMode(SettlementMode value) {
+    if (_settlementMode == value) return;
+    _settlementMode = value;
+    notifyListeners();
+  }
 }

frontend/pshared/lib/provider/payment/multiple/provider.dart

@@ -7,6 +7,7 @@ import 'package:pshared/provider/resource.dart';
 import 'package:pshared/service/payment/multiple.dart';
 import 'package:pshared/utils/exception.dart';
 
+
 class MultiPaymentProvider extends ChangeNotifier {
   late OrganizationsProvider _organization;
   late MultiQuotationProvider _quotation;

frontend/pshared/lib/provider/payment/quotation/intent_builder.dart

@@ -22,6 +22,8 @@ import 'package:pshared/utils/currency.dart';
 import 'package:pshared/utils/payment/fx_helpers.dart';
 
 class QuotationIntentBuilder {
+  static const String _settlementCurrency = 'RUB';
+
   PaymentIntent? build({
     required PaymentAmountProvider payment,
     required WalletsController wallets,
@@ -39,10 +41,12 @@ class QuotationIntentBuilder {
       data: paymentData,
     );
     final sourceCurrency = currencyCodeToString(selectedWallet.currency);
+    final amountCurrency = payment.settlementMode == SettlementMode.fixReceived
+        ? _settlementCurrency
+        : sourceCurrency;
     final amount = Money(
       amount: payment.amount.toString(),
-      // TODO: adapt to possible other sources
-      currency: sourceCurrency,
+      currency: amountCurrency,
     );
     final isCryptoToCrypto =
         paymentData is CryptoAddressPaymentMethod &&
@@ -50,7 +54,7 @@ class QuotationIntentBuilder {
             amount.currency;
     final fxIntent = FxIntentHelper.buildSellBaseBuyQuote(
       baseCurrency: sourceCurrency,
-      quoteCurrency: 'RUB', // TODO: exentd target currencies
+      quoteCurrency: _settlementCurrency, // TODO: exentd target currencies
       enabled: !isCryptoToCrypto,
     );
     return PaymentIntent(
@@ -68,7 +72,7 @@ class QuotationIntentBuilder {
       feeTreatment: payment.payerCoversFee
           ? FeeTreatment.addToSource
           : FeeTreatment.deductFromDestination,
-      settlementMode: SettlementMode.fixSource,
+      settlementMode: payment.settlementMode,
       customer: customer,
     );
   }