CW 68 exchange automatic rate selector (#472)

* Add 'Exchange provider picker'
Save user selections

* Save user's exchange providers selection

* Add text for selected providers availability

* Fix selected providers not updating

* Load limits based on highest maximum in the selected providers

* Change received and deposit amount to be the best value from the selected providers

* Add provider name next to Trade ID
Set selected provider based on amount calculated

* Grey out providers who doesn't support selected currency pair

* Fix disabled providers

* Add Provider logo in Confirm Screen

* Only choose a provider if it satisfies its limits

* Fix amount validation

* Fix typo in error message

* Add a queue of possible exchange providers sorted by the best rate to try next if one failed

* Fix string locale typo

* Add Localization for other languages

* Add Placeholder text when there are no providers selected

* Check Exchange provider availability before creating a trade

* Fix "Fixed Rate" changing unconditionally

* Enable "convert to" field regardless of the provider

* Remove "Choose one" from providers picker

* Merge Master

* Fix Conflicts with master

* Add missing isEnabled field in simple swap provider

lib/di.dart

@@ -485,7 +485,9 @@ Future setup(
       _tradesSource,
       getIt.get<ExchangeTemplateStore>(),
       getIt.get<TradesStore>(),
-      getIt.get<AppStore>().settingsStore));
+      getIt.get<AppStore>().settingsStore,
+      getIt.get<SharedPreferences>(),
+  ));
 
   getIt.registerFactory(() => ExchangeTradeViewModel(
       wallet: getIt.get<AppStore>().wallet,

lib/entities/preferences_key.dart

@@ -26,4 +26,6 @@ class PreferencesKey {
 
   static String moneroWalletUpdateV1Key(String name)
     => '${PreferencesKey.moneroWalletPasswordUpdateV1Base}_${name}';
+
+  static const exchangeProvidersSelection = 'exchange-providers-selection';
 }

lib/exchange/changenow/changenow_exchange_provider.dart

@@ -39,6 +39,9 @@ class ChangeNowExchangeProvider extends ExchangeProvider {
   @override
   bool get isAvailable => true;
 
+  @override
+  bool get isEnabled => true;
+
   @override
   ExchangeProviderDescription get description =>
       ExchangeProviderDescription.changeNow;

lib/exchange/exchange_provider.dart

@@ -13,6 +13,7 @@ abstract class ExchangeProvider {
   List<ExchangePair> pairList;
   ExchangeProviderDescription description;
   bool get isAvailable;
+  bool get isEnabled;
 
   @override
   String toString() => title;

lib/exchange/exchange_provider_description.dart

@@ -2,20 +2,23 @@ import 'package:cw_core/enumerable_item.dart';
 
 class ExchangeProviderDescription extends EnumerableItem<int>
     with Serializable<int> {
-  const ExchangeProviderDescription({String title, int raw})
+  const ExchangeProviderDescription({String title, int raw, this.horizontalLogo = false, this.image})
       : super(title: title, raw: raw);
 
-  static const xmrto = ExchangeProviderDescription(title: 'XMR.TO', raw: 0);
+  final bool horizontalLogo;
+  final String image;
+
+  static const xmrto = ExchangeProviderDescription(title: 'XMR.TO', raw: 0, image: 'assets/images/xmrto.png');
   static const changeNow =
-      ExchangeProviderDescription(title: 'ChangeNOW', raw: 1);
+      ExchangeProviderDescription(title: 'ChangeNOW', raw: 1, image: 'assets/images/changenow.png');
   static const morphToken =
-      ExchangeProviderDescription(title: 'MorphToken', raw: 2);
+      ExchangeProviderDescription(title: 'MorphToken', raw: 2, image: 'assets/images/morph.png');
 
    static const sideShift =
-      ExchangeProviderDescription(title: 'SideShift', raw: 3);
+      ExchangeProviderDescription(title: 'SideShift', raw: 3, image: 'assets/images/sideshift.png');
-  
+
-   static const simpleSwap =
+  static const simpleSwap =
-      ExchangeProviderDescription(title: 'SimpleSwap', raw: 4);
+      ExchangeProviderDescription(title: 'SimpleSwap', raw: 4, image: 'assets/images/simpleSwap.png');
 
   static ExchangeProviderDescription deserialize({int raw}) {
     switch (raw) {

lib/exchange/morphtoken/morphtoken_exchange_provider.dart

@@ -63,6 +63,9 @@ class MorphTokenExchangeProvider extends ExchangeProvider {
   @override
   bool get isAvailable => true;
 
+  @override
+  bool get isEnabled => true;
+
   @override
   ExchangeProviderDescription get description =>
       ExchangeProviderDescription.morphToken;

lib/exchange/sideshift/sideshift_exchange_provider.dart

@@ -244,6 +244,9 @@ class SideShiftExchangeProvider extends ExchangeProvider {
   @override
   bool get isAvailable => true;
 
+  @override
+  bool get isEnabled => true;
+
   @override
   String get title => 'SideShift';
 

lib/exchange/simpleswap/simpleswap_exchange_provider.dart

@@ -197,6 +197,9 @@ class SimpleSwapExchangeProvider extends ExchangeProvider {
   @override
   bool get isAvailable => true;
 
+  @override
+  bool get isEnabled => true;
+
   @override
   String get title => 'SimpleSwap';
 

lib/exchange/xmrto/xmrto_exchange_provider.dart

@@ -44,6 +44,9 @@ class XMRTOExchangeProvider extends ExchangeProvider {
   @override
   bool get isAvailable => _isAvailable;
 
+  @override
+  bool get isEnabled => true;
+
   @override
   ExchangeProviderDescription get description =>
       ExchangeProviderDescription.xmrto;

lib/src/screens/exchange/exchange_page.dart

@@ -354,8 +354,12 @@ class ExchangePage extends BasePage {
                     padding: EdgeInsets.only(bottom: 15),
                     child: Observer(builder: (_) {
                       final description = exchangeViewModel.isFixedRateMode
+                          ? exchangeViewModel.isAvailableInSelected
                               ? S.of(context).amount_is_guaranteed
-                              : S.of(context).amount_is_estimate;
+                              : S.of(context).fixed_pair_not_supported
+                          : exchangeViewModel.isAvailableInSelected
+                              ? S.of(context).amount_is_estimate
+                              : S.of(context).variable_pair_not_supported;
                       return Center(
                         child: Text(
                           description,
@@ -399,8 +403,8 @@ class ExchangePage extends BasePage {
                           },
                           color: Theme.of(context).accentTextTheme.body2.color,
                           textColor: Colors.white,
-                          isLoading:
+                          isDisabled: exchangeViewModel.selectedProviders.isEmpty,
-                              exchangeViewModel.tradeState is TradeIsCreating)),
+                          isLoading: exchangeViewModel.tradeState is TradeIsCreating)),
                 ]),
               )),
         ));
@@ -518,13 +522,6 @@ class ExchangePage extends BasePage {
     exchangeViewModel.changeReceiveCurrency(
         currency: CryptoCurrency.fromString(template.receiveCurrency));
 
-    switch (template.provider) {
-      case 'ChangeNOW':
-        exchangeViewModel.changeProvider(
-            provider: exchangeViewModel.providerList[0]);
-        break;
-    }
-
     exchangeViewModel.changeDepositAmount(amount: template.amount);
     exchangeViewModel.depositAddress = template.depositAddress;
     exchangeViewModel.receiveAddress = template.receiveAddress;
@@ -744,11 +741,10 @@ class ExchangePage extends BasePage {
     });
 
     _receiveAmountFocus.addListener(() {
-     if(receiveAmountController.text.isNotEmpty){  
+      if (_receiveAmountFocus.hasFocus) {
-      exchangeViewModel.isFixedRateMode = true;
+        exchangeViewModel.isFixedRateMode = true;
-     }
+      }
-      exchangeViewModel.changeReceiveAmount(
+      exchangeViewModel.changeReceiveAmount(amount: receiveAmountController.text);
-        amount: receiveAmountController.text);
     });
 
     _depositAmountFocus.addListener(() {

lib/src/screens/exchange/widgets/present_provider_picker.dart

@@ -1,11 +1,9 @@
 import 'package:cake_wallet/src/widgets/alert_with_one_action.dart';
+import 'package:cake_wallet/src/widgets/check_box_picker.dart';
 import 'package:cake_wallet/utils/show_pop_up.dart';
 import 'package:flutter/material.dart';
-import 'package:cake_wallet/exchange/exchange_provider_description.dart';
-import 'package:cake_wallet/exchange/exchange_provider.dart';
 import 'package:flutter_mobx/flutter_mobx.dart';
 import 'package:cake_wallet/generated/i18n.dart';
-import 'package:cake_wallet/src/widgets/picker.dart';
 import 'package:cake_wallet/view_model/exchange/exchange_view_model.dart';
 
 class PresentProviderPicker extends StatelessWidget {
@@ -38,11 +36,16 @@ class PresentProviderPicker extends StatelessWidget {
                         fontWeight: FontWeight.w600,
                         color: Colors.white)),
                 Observer(
-                    builder: (_) => Text('${exchangeViewModel.provider.title}',
+                    builder: (_) => Text(
-                        style: TextStyle(
+                        exchangeViewModel.selectedProviders.isEmpty
-                            fontSize: 10.0,
+                            ? S.of(context).choose_one
-                            fontWeight: FontWeight.w500,
+                            : exchangeViewModel.selectedProviders.length > 1
-                            color: Theme.of(context).textTheme.headline.color)))
+                              ? S.of(context).automatic
+                              : exchangeViewModel.selectedProviders.first.title,
+                            style: TextStyle(
+                                fontSize: 10.0,
+                                fontWeight: FontWeight.w500,
+                                color: Theme.of(context).textTheme.headline.color)))
               ],
             ),
             SizedBox(width: 5),
@@ -54,41 +57,19 @@ class PresentProviderPicker extends StatelessWidget {
         ));
   }
 
-  void _presentProviderPicker(BuildContext context) {
+  void _presentProviderPicker(BuildContext context) async {
-    final items = exchangeViewModel.providersForCurrentPair();
+    await showPopUp<void>(
-    final selectedItem = items.indexOf(exchangeViewModel.provider);
+        builder: (BuildContext popUpContext) => CheckBoxPicker(
-    final images = <Image>[];
+            items: exchangeViewModel.providerList
-    String description;
+                .map((e) => CheckBoxItem(
-
+                      e.title,
-    for (var provider in items) {
+                      exchangeViewModel.selectedProviders.contains(e),
-      switch (provider.description) {
+                      isDisabled: !exchangeViewModel.providersForCurrentPair().contains(e),
-        case ExchangeProviderDescription.xmrto:
+                    ))
-          images.add(Image.asset('assets/images/xmr_btc.png'));
+                .toList(),
-          break;
-        case ExchangeProviderDescription.changeNow:
-          images.add(Image.asset('assets/images/change_now.png'));
-          break;
-        case ExchangeProviderDescription.morphToken:
-          images.add(Image.asset('assets/images/morph_icon.png'));
-          break;
-        case ExchangeProviderDescription.sideShift:
-          images.add(Image.asset('assets/images/sideshift.png', width: 20));
-          break;
-        case ExchangeProviderDescription.simpleSwap:
-          images.add(Image.asset('assets/images/simpleSwap.png',  width: 20));
-          break;
-      }
-    }
-
-    showPopUp<void>(
-        builder: (BuildContext popUpContext) => Picker(
-            items: items,
-            images: images,
-            selectedAtIndex: selectedItem,
             title: S.of(context).change_exchange_provider,
-            description: description,
+            onChanged: (int index, bool value) {
-            onItemSelected: (ExchangeProvider provider) {
+              if (!exchangeViewModel.providerList[index].isAvailable) {
-              if (!provider.isAvailable) {
                 showPopUp<void>(
                     builder: (BuildContext popUpContext) => AlertWithOneAction(
                         alertTitle: 'Error',
@@ -98,8 +79,14 @@ class PresentProviderPicker extends StatelessWidget {
                     context: context);
                 return;
               }
-              exchangeViewModel.changeProvider(provider: provider);
+              if (value) {
+                exchangeViewModel.addExchangeProvider(exchangeViewModel.providerList[index]);
+              } else {
+                exchangeViewModel.removeExchangeProvider(exchangeViewModel.providerList[index]);
+              }
             }),
         context: context);
+
+    exchangeViewModel.saveSelectedProviders();
   }
 }

lib/src/screens/exchange_trade/exchange_confirm_page.dart

@@ -1,3 +1,4 @@
+import 'package:cake_wallet/exchange/exchange_provider_description.dart';
 import 'package:cake_wallet/store/dashboard/trades_store.dart';
 import 'package:cake_wallet/utils/show_bar.dart';
 import 'package:flutter/material.dart';
@@ -56,7 +57,7 @@ class ExchangeConfirmPage extends BasePage {
                         crossAxisAlignment: CrossAxisAlignment.center,
                         children: <Widget>[
                           Text(
-                            S.of(context).trade_id,
+                            "${trade.provider.title} ${S.of(context).trade_id}",
                             style: TextStyle(
                                 fontSize: 12.0,
                                 fontWeight: FontWeight.w500,
@@ -101,7 +102,23 @@ class ExchangeConfirmPage extends BasePage {
                   ],
                 ),
               ),
-              Flexible(child: Offstage()),
+              Flexible(
+                child: Center(
+                  child: Row(
+                    mainAxisAlignment: MainAxisAlignment.center,
+                    children: [
+                      (trade.provider.image?.isNotEmpty ?? false)
+                          ? Image.asset(trade.provider.image, height: 50)
+                          : const SizedBox(),
+                      if (!trade.provider.horizontalLogo)
+                        Padding(
+                          padding: const EdgeInsets.symmetric(horizontal: 8.0),
+                          child: Text(trade.provider.title),
+                        ),
+                    ],
+                  ),
+                ),
+              ),
             ],
           )),
           PrimaryButton(

lib/src/widgets/check_box_picker.dart

@@ -0,0 +1,166 @@
+import 'dart:ui';
+import 'package:cake_wallet/palette.dart';
+import 'package:flutter/cupertino.dart';
+import 'package:flutter/material.dart';
+import 'package:cake_wallet/src/widgets/alert_background.dart';
+import 'package:cake_wallet/src/widgets/alert_close_button.dart';
+import 'package:cake_wallet/generated/i18n.dart';
+
+class CheckBoxPicker extends StatefulWidget {
+  CheckBoxPicker({
+    @required this.items,
+    @required this.onChanged,
+    this.title,
+    this.displayItem,
+    this.isSeparated = true,
+  });
+
+  final List<CheckBoxItem> items;
+  final String title;
+  final Widget Function(CheckBoxItem) displayItem;
+  final bool isSeparated;
+  final Function(int, bool) onChanged;
+
+  @override
+  CheckBoxPickerState createState() => CheckBoxPickerState(items);
+}
+
+class CheckBoxPickerState extends State<CheckBoxPicker> {
+  CheckBoxPickerState(this.items);
+
+  final List<CheckBoxItem> items;
+
+  ScrollController controller = ScrollController();
+
+  @override
+  Widget build(BuildContext context) {
+    return AlertBackground(
+      child: Stack(
+        alignment: Alignment.center,
+        children: <Widget>[
+          Column(
+            mainAxisSize: MainAxisSize.min,
+            children: <Widget>[
+              if (widget.title?.isNotEmpty ?? false)
+                Container(
+                  padding: EdgeInsets.symmetric(horizontal: 24),
+                  child: Text(
+                    widget.title,
+                    textAlign: TextAlign.center,
+                    style: TextStyle(
+                      fontSize: 18,
+                      fontFamily: 'Lato',
+                      fontWeight: FontWeight.bold,
+                      decoration: TextDecoration.none,
+                      color: Colors.white,
+                    ),
+                  ),
+                ),
+              Padding(
+                padding: EdgeInsets.only(left: 24, right: 24, top: 24),
+                child: ClipRRect(
+                  borderRadius: BorderRadius.all(Radius.circular(30)),
+                  child: Container(
+                    color: Theme.of(context).accentTextTheme.title.color,
+                    child: ConstrainedBox(
+                      constraints: BoxConstraints(
+                        maxHeight: MediaQuery.of(context).size.height * 0.65,
+                      ),
+                      child: Column(
+                        mainAxisSize: MainAxisSize.min,
+                        children: [
+                          Flexible(
+                            child: Stack(
+                              alignment: Alignment.center,
+                              children: <Widget>[
+                                (items?.length ?? 0) > 3
+                                    ? Scrollbar(
+                                        controller: controller,
+                                        child: itemsList(),
+                                      )
+                                    : itemsList(),
+                              ],
+                            ),
+                          ),
+                        ],
+                      ),
+                    ),
+                  ),
+                ),
+              )
+            ],
+          ),
+          AlertCloseButton(),
+        ],
+      ),
+    );
+  }
+
+  Widget itemsList() {
+    return Container(
+      color: Theme.of(context).accentTextTheme.headline6.backgroundColor,
+      child: ListView.separated(
+        padding: EdgeInsets.zero,
+        controller: controller,
+        shrinkWrap: true,
+        separatorBuilder: (context, index) => widget.isSeparated
+            ? Divider(
+                color: Theme.of(context).accentTextTheme.title.backgroundColor,
+                height: 1,
+              )
+            : const SizedBox(),
+        itemCount: items == null || items.isEmpty ? 0 : items.length,
+        itemBuilder: (context, index) => buildItem(index),
+      ),
+    );
+  }
+
+  Widget buildItem(int index) {
+    final item = items[index];
+
+    return GestureDetector(
+      onTap: () {
+        Navigator.of(context).pop();
+      },
+      child: Container(
+        height: 55,
+        color: Theme.of(context).accentTextTheme.headline6.color,
+        padding: EdgeInsets.only(left: 24, right: 24),
+        child: CheckboxListTile(
+          value: item.value,
+          activeColor: item.value
+              ? Palette.blueCraiola
+              : Theme.of(context).accentTextTheme.subhead.decorationColor,
+          checkColor: Colors.white,
+          title: widget.displayItem?.call(item) ??
+              Text(
+                item.title,
+                style: TextStyle(
+                  fontSize: 14,
+                  fontFamily: 'Lato',
+                  fontWeight: FontWeight.w600,
+                  color: item.isDisabled
+                      ? Colors.grey.withOpacity(0.5)
+                      : Theme.of(context).primaryTextTheme.title.color,
+                  decoration: TextDecoration.none,
+                ),
+              ),
+          onChanged: (bool value) {
+            item.value = value;
+            widget.onChanged(index, value);
+            setState(() {});
+          },
+          controlAffinity: ListTileControlAffinity.leading,
+        ),
+      ),
+    );
+  }
+}
+
+class CheckBoxItem {
+  CheckBoxItem(this.title, this.value, {this.isDisabled = false});
+
+  final String title;
+  final bool isDisabled;
+  bool value;
+}

lib/view_model/exchange/exchange_trade_view_model.dart

@@ -116,7 +116,7 @@ abstract class ExchangeTradeViewModelBase with Store {
     items?.clear();
 
     items.add(ExchangeTradeItem(
-        title: S.current.id, data: '${trade.id}', isCopied: true));
+        title: "${trade.provider.title} ${S.current.id}", data: '${trade.id}', isCopied: true));
 
     if (trade.extraId != null) {
       final title = trade.from == CryptoCurrency.xrp

lib/view_model/exchange/exchange_view_model.dart

@@ -1,3 +1,7 @@
+import 'dart:collection';
+import 'dart:convert';
+
+import 'package:cake_wallet/entities/preferences_key.dart';
 import 'package:cake_wallet/exchange/sideshift/sideshift_exchange_provider.dart';
 import 'package:cake_wallet/exchange/sideshift/sideshift_request.dart';
 import 'package:cake_wallet/exchange/simpleswap/simpleswap_exchange_provider.dart';
@@ -27,6 +31,7 @@ import 'package:cake_wallet/exchange/morphtoken/morphtoken_exchange_provider.dar
 import 'package:cake_wallet/exchange/morphtoken/morphtoken_request.dart';
 import 'package:cake_wallet/store/templates/exchange_template_store.dart';
 import 'package:cake_wallet/exchange/exchange_template.dart';
+import 'package:shared_preferences/shared_preferences.dart';
 
 part 'exchange_view_model.g.dart';
 
@@ -34,10 +39,24 @@ class ExchangeViewModel = ExchangeViewModelBase with _$ExchangeViewModel;
 
 abstract class ExchangeViewModelBase with Store {
   ExchangeViewModelBase(this.wallet, this.trades, this._exchangeTemplateStore,
-      this.tradesStore, this._settingsStore) {
+      this.tradesStore, this._settingsStore, this.sharedPreferences) {
     const excludeDepositCurrencies = [CryptoCurrency.xhv];
     const excludeReceiveCurrencies = [CryptoCurrency.xlm, CryptoCurrency.xrp, CryptoCurrency.bnb, CryptoCurrency.xhv];
     providerList = [ChangeNowExchangeProvider(), SideShiftExchangeProvider(), SimpleSwapExchangeProvider()];
+
+    currentTradeAvailableProviders = SplayTreeMap<double, ExchangeProvider>();
+
+    final Map<String, dynamic> exchangeProvidersSelection = json
+        .decode(sharedPreferences.getString(PreferencesKey.exchangeProvidersSelection) ?? "{}") as Map<String, dynamic>;
+
+    /// if the provider is not in the user settings (user's first time or newly added provider)
+    /// then use its default value decided by us
+    selectedProviders = ObservableList.of(providerList.where(
+            (element) => exchangeProvidersSelection[element.title] == null
+            ? element.isEnabled
+            : (exchangeProvidersSelection[element.title] as bool))
+        .toList());
+
     _initialPairBasedOnWallet();
     isDepositAddressEnabled = !(depositCurrency == wallet.currency);
     isReceiveAddressEnabled = !(receiveCurrency == wallet.currency);
@@ -48,7 +67,7 @@ abstract class ExchangeViewModelBase with Store {
         ? wallet.walletAddresses.address : '';
     limitsState = LimitsInitialState();
     tradeState = ExchangeTradeStateInitial();
-    _cryptoNumberFormat = NumberFormat()..maximumFractionDigits = 12;
+    _cryptoNumberFormat = NumberFormat()..maximumFractionDigits = wallet.type == WalletType.bitcoin ? 8 : 12;
     provider = providersForCurrentPair().first;
     final initialProvider = provider;
     provider.checkIsAvailable().then((bool isAvailable) {
@@ -79,10 +98,20 @@ abstract class ExchangeViewModelBase with Store {
   final Box<Trade> trades;
   final ExchangeTemplateStore _exchangeTemplateStore;
   final TradesStore tradesStore;
+  final SharedPreferences sharedPreferences;
 
   @observable
   ExchangeProvider provider;
 
+  /// Maps in dart are not sorted by default
+  /// SplayTreeMap is a map sorted by keys
+  /// will use it to sort available providers
+  /// depending on the amount they yield for the current trade
+  SplayTreeMap<double, ExchangeProvider> currentTradeAvailableProviders;
+
+  @observable
+  ObservableList<ExchangeProvider> selectedProviders;
+
   @observable
   List<ExchangeProvider> providerList;
 
@@ -147,17 +176,7 @@ abstract class ExchangeViewModelBase with Store {
 
   NumberFormat _cryptoNumberFormat;
 
-  SettingsStore _settingsStore;
+  final SettingsStore _settingsStore;
-
-  @action
-  void changeProvider({ExchangeProvider provider}) {
-    this.provider = provider;
-    depositAmount = '';
-    receiveAmount = '';
-    isFixedRateMode = false;
-    _defineIsReceiveAmountEditable();
-    loadLimits();
-  }
 
   @action
   void changeDepositCurrency({CryptoCurrency currency}) {
@@ -188,20 +207,46 @@ abstract class ExchangeViewModelBase with Store {
       return;
     }
 
-    final _amount = double.parse(amount.replaceAll(',', '.')) ?? 0;
+    final _enteredAmount = double.parse(amount.replaceAll(',', '.')) ?? 0;
 
-    provider
+    currentTradeAvailableProviders.clear();
-        .calculateAmount(
+    for (var provider in selectedProviders) {
-            from: receiveCurrency,
+      provider
-            to: depositCurrency,
+          .calculateAmount(
-            amount: _amount,
+              from: receiveCurrency,
-            isFixedRateMode: isFixedRateMode,
+              to: depositCurrency,
-            isReceiveAmount: true)
+              amount: _enteredAmount,
-        .then((amount) => _cryptoNumberFormat
+              isFixedRateMode: isFixedRateMode,
+              isReceiveAmount: true)
+          .then((amount) {
+
+        final from = isFixedRateMode
+            ? receiveCurrency
+            : depositCurrency;
+        final to = isFixedRateMode
+            ? depositCurrency
+            : receiveCurrency;
+
+        provider.fetchLimits(
+          from: from,
+          to: to,
+          isFixedRateMode: isFixedRateMode,
+        ).then((limits) {
+          /// if the entered amount doesn't exceed the limits of this provider
+          if ((limits.max ?? double.maxFinite) >= _enteredAmount
+              && (limits.min ?? 0) <= _enteredAmount) {
+            /// add this provider as its valid for this trade
+            /// will be sorted ascending already since
+            /// we seek the least deposit amount
+            currentTradeAvailableProviders[amount] = provider;
+          }
+          return amount;
+        }).then((amount) => depositAmount = _cryptoNumberFormat
             .format(amount)
             .toString()
-            .replaceAll(RegExp('\\,'), ''))
+            .replaceAll(RegExp('\\,'), ''));
-        .then((amount) => depositAmount = amount);
+      });
+    }
   }
 
   @action
@@ -215,23 +260,56 @@ abstract class ExchangeViewModelBase with Store {
       return;
     }
 
-    final _amount = double.parse(amount.replaceAll(',', '.')) ?? 0;
+    final _enteredAmount = double.tryParse(amount.replaceAll(',', '.')) ?? 0;
-    provider
+
-        .calculateAmount(
+    currentTradeAvailableProviders.clear();
-            from: depositCurrency,
+    for (var provider in selectedProviders) {
-            to: receiveCurrency,
+      provider
-            amount: _amount,
+          .calculateAmount(
-            isFixedRateMode: isFixedRateMode,
+              from: depositCurrency,
-            isReceiveAmount: false)
+              to: receiveCurrency,
-        .then((amount) => _cryptoNumberFormat
+              amount: _enteredAmount,
+              isFixedRateMode: isFixedRateMode,
+              isReceiveAmount: false)
+          .then((amount) {
+
+        final from = isFixedRateMode
+            ? receiveCurrency
+            : depositCurrency;
+        final to = isFixedRateMode
+            ? depositCurrency
+            : receiveCurrency;
+
+        provider.fetchLimits(
+          from: from,
+          to: to,
+          isFixedRateMode: isFixedRateMode,
+        ).then((limits) {
+
+          /// if the entered amount doesn't exceed the limits of this provider
+          if ((limits.max ?? double.maxFinite) >= _enteredAmount
+              && (limits.min ?? 0) <= _enteredAmount) {
+            /// add this provider as its valid for this trade
+            /// subtract from maxFinite so the provider
+            /// with the largest amount would be sorted ascending
+            currentTradeAvailableProviders[double.maxFinite - amount] = provider;
+          }
+          return amount;
+        }).then((amount) => receiveAmount =
+            receiveAmount = _cryptoNumberFormat
             .format(amount)
             .toString()
-            .replaceAll(RegExp('\\,'), ''))
+            .replaceAll(RegExp('\\,'), ''));
-        .then((amount) => receiveAmount = amount);
+      });
+    }
   }
 
   @action
   Future loadLimits() async {
+    if (selectedProviders.isEmpty) {
+      return;
+    }
+
     limitsState = LimitsIsLoading();
 
     try {
@@ -241,10 +319,29 @@ abstract class ExchangeViewModelBase with Store {
       final to = isFixedRateMode
         ? depositCurrency
         : receiveCurrency;
-      limits = await provider.fetchLimits(
+
+      limits = await selectedProviders.first.fetchLimits(
           from: from,
           to: to,
           isFixedRateMode: isFixedRateMode);
+
+      /// if the first provider limits is bounded then check with other providers
+      /// for the highest maximum limit
+      if (limits.max != null) {
+        for (int i = 1;i < selectedProviders.length;i++) {
+          final Limits tempLimits = await selectedProviders[i].fetchLimits(
+              from: from,
+              to: to,
+              isFixedRateMode: isFixedRateMode);
+
+          /// set the limits with the maximum provider limit
+          /// if there is a provider with null max then it's the maximum limit
+          if ((tempLimits.max ?? double.maxFinite) > limits.max) {
+            limits = tempLimits;
+          }
+        }
+      }
+
       limitsState = LimitsLoadedSuccessfully(limits: limits);
     } catch (e) {
       limitsState = LimitsLoadedFailure(error: e.toString());
@@ -255,102 +352,97 @@ abstract class ExchangeViewModelBase with Store {
   Future createTrade() async {
     TradeRequest request;
     String amount;
-    CryptoCurrency currency;
 
-     if (provider is SideShiftExchangeProvider) {
+    for (var provider in currentTradeAvailableProviders.values) {
-      request = SideShiftRequest(
+      if (!(await provider.checkIsAvailable())) {
+        continue;
+      }
+
+      if (provider is SideShiftExchangeProvider) {
+        request = SideShiftRequest(
           depositMethod: depositCurrency,
           settleMethod: receiveCurrency,
           depositAmount: depositAmount?.replaceAll(',', '.'),
           settleAddress: receiveAddress,
           refundAddress: depositAddress,
-          );
+        );
-      amount = depositAmount;
+        amount = depositAmount;
-      currency = depositCurrency;
+      }
-    }
 
-    if (provider is SimpleSwapExchangeProvider) {
+      if (provider is SimpleSwapExchangeProvider) {
-      request = SimpleSwapRequest(
+        request = SimpleSwapRequest(
           from: depositCurrency,
           to: receiveCurrency,
           amount: depositAmount?.replaceAll(',', '.'),
           address: receiveAddress,
           refundAddress: depositAddress,
-          );
+        );
-      amount = depositAmount;
+        amount = depositAmount;
-      currency = depositCurrency;
+      }
-    }
 
-    if (provider is XMRTOExchangeProvider) {
+      if (provider is XMRTOExchangeProvider) {
-      request = XMRTOTradeRequest(
+        request = XMRTOTradeRequest(
-          from: depositCurrency,
+            from: depositCurrency,
-          to: receiveCurrency,
+            to: receiveCurrency,
-          amount: depositAmount?.replaceAll(',', '.'),
+            amount: depositAmount?.replaceAll(',', '.'),
-          receiveAmount: receiveAmount?.replaceAll(',', '.'),
+            receiveAmount: receiveAmount?.replaceAll(',', '.'),
-          address: receiveAddress,
+            address: receiveAddress,
-          refundAddress: depositAddress,
+            refundAddress: depositAddress,
-          isBTCRequest: isReceiveAmountEntered);
+            isBTCRequest: isReceiveAmountEntered);
-      amount = depositAmount;
+        amount = depositAmount;
-      currency = depositCurrency;
+      }
-    }
 
-    if (provider is ChangeNowExchangeProvider) {
+      if (provider is ChangeNowExchangeProvider) {
-      request = ChangeNowRequest(
+        request = ChangeNowRequest(
-          from: depositCurrency,
+            from: depositCurrency,
-          to: receiveCurrency,
+            to: receiveCurrency,
-          fromAmount: depositAmount?.replaceAll(',', '.'),
+            fromAmount: depositAmount?.replaceAll(',', '.'),
-          toAmount: receiveAmount?.replaceAll(',', '.'),
+            toAmount: receiveAmount?.replaceAll(',', '.'),
-          refundAddress: depositAddress,
+            refundAddress: depositAddress,
-          address: receiveAddress,
+            address: receiveAddress,
-          isReverse: isReverse);
+            isReverse: isReverse);
-      amount = isReverse ? receiveAmount : depositAmount;
+        amount = isReverse ? receiveAmount : depositAmount;
-      currency = depositCurrency;
+      }
-    }
 
-    if (provider is MorphTokenExchangeProvider) {
+      if (provider is MorphTokenExchangeProvider) {
-      request = MorphTokenRequest(
+        request = MorphTokenRequest(
-          from: depositCurrency,
+            from: depositCurrency,
-          to: receiveCurrency,
+            to: receiveCurrency,
-          amount: depositAmount?.replaceAll(',', '.'),
+            amount: depositAmount?.replaceAll(',', '.'),
-          refundAddress: depositAddress,
+            refundAddress: depositAddress,
-          address: receiveAddress);
+            address: receiveAddress);
-      amount = depositAmount;
+        amount = depositAmount;
-      currency = depositCurrency;
+      }
-    }
 
-    amount = amount.replaceAll(',', '.');
+      amount = amount.replaceAll(',', '.');
 
-    if (limitsState is LimitsLoadedSuccessfully && amount != null) {
+      if (limitsState is LimitsLoadedSuccessfully && amount != null) {
-      if (double.parse(amount) < limits.min) {
+        if (double.parse(amount) < limits.min) {
-        tradeState = TradeIsCreatedFailure(
+          continue;
-            title: provider.title,
+        } else if (limits.max != null && double.parse(amount) > limits.max) {
-            error: S.current.error_text_minimal_limit('${provider.description}',
+          continue;
-                '${limits.min}', currency.toString()));
+        } else {
-      } else if (limits.max != null && double.parse(amount) > limits.max) {
+          try {
-        tradeState = TradeIsCreatedFailure(
+            tradeState = TradeIsCreating();
-            title: provider.title,
+            final trade = await provider.createTrade(
-            error: S.current.error_text_maximum_limit('${provider.description}',
+                request: request, isFixedRateMode: isFixedRateMode);
-                '${limits.max}', currency.toString()));
+            trade.walletId = wallet.id;
-      } else {
+            tradesStore.setTrade(trade);
-        try {
+            await trades.add(trade);
-          tradeState = TradeIsCreating();
+            tradeState = TradeIsCreatedSuccessfully(trade: trade);
-          final trade = await provider.createTrade(
+            /// return after the first successful trade
-              request: request, isFixedRateMode: isFixedRateMode);
+            return;
-          trade.walletId = wallet.id;
+          } catch (e) {
-          tradesStore.setTrade(trade);
+            continue;
-          await trades.add(trade);
+          }
-          tradeState = TradeIsCreatedSuccessfully(trade: trade);
-        } catch (e) {
-          tradeState =
-              TradeIsCreatedFailure(title: provider.title, error: e.toString());
         }
       }
-    } else {
-      tradeState = TradeIsCreatedFailure(
-          title: provider.title,
-          error: S.current
-              .error_text_limits_loading_failed('${provider.description}'));
     }
+
+    /// if the code reached here then none of the providers succeeded
+    tradeState = TradeIsCreatedFailure(
+        title: S.current.trade_not_created,
+        error: S.current.none_of_selected_providers_can_exchange);
   }
 
   @action
@@ -414,7 +506,7 @@ abstract class ExchangeViewModelBase with Store {
     final providers = providerList
         .where((provider) => provider.pairList
             .where((pair) =>
-                pair.from == depositCurrency && pair.to == receiveCurrency)
+                pair.from == (from ?? depositCurrency) && pair.to == (to ?? receiveCurrency))
             .isNotEmpty)
         .toList();
 
@@ -422,27 +514,8 @@ abstract class ExchangeViewModelBase with Store {
   }
 
   void _onPairChange() {
-    final isPairExist = provider.pairList
+    depositAmount = '';
-        .where((pair) =>
+    receiveAmount = '';
-            pair.from == depositCurrency && pair.to == receiveCurrency)
-        .isNotEmpty;
-
-    if (isPairExist) {
-      final provider =
-          _providerForPair(from: depositCurrency, to: receiveCurrency);
-
-      if (provider != null) {
-        changeProvider(provider: provider);
-      }
-    } else {
-      depositAmount = '';
-      receiveAmount = '';
-    }
-  }
-
-  ExchangeProvider _providerForPair({CryptoCurrency from, CryptoCurrency to}) {
-    final providers = _providersForPair(from: from, to: to);
-    return providers.isNotEmpty ? providers[0] : null;
   }
 
   void _initialPairBasedOnWallet() {
@@ -473,6 +546,45 @@ abstract class ExchangeViewModelBase with Store {
       isReceiveAmountEditable = false;
     }*/
     //isReceiveAmountEditable = false;
-    isReceiveAmountEditable = provider is ChangeNowExchangeProvider ||  provider is SimpleSwapExchangeProvider;
+    // isReceiveAmountEditable = selectedProviders.any((provider) => provider is ChangeNowExchangeProvider);
+    // isReceiveAmountEditable = provider is ChangeNowExchangeProvider ||  provider is SimpleSwapExchangeProvider;
+    isReceiveAmountEditable = true;
+  }
+
+  @action
+  void addExchangeProvider(ExchangeProvider provider) {
+    selectedProviders.add(provider);
+  }
+
+  @action
+  void removeExchangeProvider(ExchangeProvider provider) {
+    selectedProviders.remove(provider);
+  }
+
+  @action
+  void saveSelectedProviders() {
+    depositAmount = '';
+    receiveAmount = '';
+    isFixedRateMode = false;
+    _defineIsReceiveAmountEditable();
+    loadLimits();
+
+    final Map<String, dynamic> exchangeProvidersSelection = json
+        .decode(sharedPreferences.getString(PreferencesKey.exchangeProvidersSelection) ?? "{}") as Map<String, dynamic>;
+
+    exchangeProvidersSelection.updateAll((key, dynamic value) => false);
+    for (var provider in selectedProviders) {
+      exchangeProvidersSelection[provider.title] = true;
+    }
+
+    sharedPreferences.setString(
+      PreferencesKey.exchangeProvidersSelection,
+      json.encode(exchangeProvidersSelection),
+    );
+  }
+
+  bool get isAvailableInSelected {
+    final providersForPair = providersForCurrentPair();
+    return selectedProviders.any((element) => element.isAvailable && providersForPair.contains(element));
   }
 }

res/values/strings_de.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "Handel für ${title} wird nicht erstellt.",
-  "trade_not_created" : "Handel nicht erstellt.",
+  "trade_not_created" : "Handel nicht erstellt",
   "trade_id_not_found" : "Handel ${tradeId} von ${title} nicht gefunden.",
   "trade_not_found" : "Handel nicht gefunden.",
 
@@ -586,7 +586,7 @@
   "use_card_info_two": "Tegoeden worden omgezet naar USD wanneer ze op de prepaid-rekening staan, niet in digitale valuta.",
   "use_card_info_three": "Gebruik de digitale kaart online of met contactloze betaalmethoden.",
   "optionally_order_card": "Optioneel een fysieke kaart bestellen.",
-  "hide_details" : "Details verbergen", 
+  "hide_details" : "Details verbergen",
   "show_details" : "Toon details",
   "upto": "tot ${value}",
   "discount": "Bespaar ${value}%",
@@ -634,5 +634,10 @@
   "contact_support": "Support kontaktieren",
   "gift_cards_unavailable": "Geschenkkarten können derzeit nur über Monero, Bitcoin und Litecoin erworben werden",
   "introducing_cake_pay":  "Einführung von Cake Pay!",
-  "cake_pay_learn_more": "Karten sofort in der App kaufen und einlösen!\nWischen Sie nach rechts, um mehr zu erfahren!"
+  "cake_pay_learn_more": "Karten sofort in der App kaufen und einlösen!\nWischen Sie nach rechts, um mehr zu erfahren!",
+  "automatic": "Automatisch",
+  "fixed_pair_not_supported": "Dieses feste Paar wird von den ausgewählten Vermittlungsstellen nicht unterstützt",
+  "variable_pair_not_supported": "Dieses Variablenpaar wird von den ausgewählten Börsen nicht unterstützt",
+  "none_of_selected_providers_can_exchange": "Keiner der ausgewählten Anbieter kann diesen Austausch vornehmen",
+  "choose_one": "Wähle ein"
 }

res/values/strings_en.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "Trade for ${title} is not created.",
-  "trade_not_created" : "Trade not created.",
+  "trade_not_created" : "Trade not created",
   "trade_id_not_found" : "Trade ${tradeId} of ${title} not found.",
   "trade_not_found" : "Trade not found.",
 
@@ -634,5 +634,10 @@
   "contact_support": "Contact Support",
   "gift_cards_unavailable": "Gift cards are available for purchase only with Monero, Bitcoin, and Litecoin at this time",
   "introducing_cake_pay":  "Introducing Cake Pay!",
-  "cake_pay_learn_more": "Instantly purchase and redeem cards in the app!\nSwipe right to learn more!"
+  "cake_pay_learn_more": "Instantly purchase and redeem cards in the app!\nSwipe right to learn more!",
+  "automatic": "Automatic",
+  "fixed_pair_not_supported": "This fixed pair is not supported with the selected exchanges",
+  "variable_pair_not_supported": "This variable pair is not supported with the selected exchanges",
+  "none_of_selected_providers_can_exchange": "None of the selected providers can make this exchange",
+  "choose_one": "Choose one"
 }

res/values/strings_es.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "Comercio por ${title} no se crea.",
-  "trade_not_created" : "Comercio no se crea.",
+  "trade_not_created" : "Comercio no se crea",
   "trade_id_not_found" : "Comercio ${tradeId} de ${title} no encontrado.",
   "trade_not_found" : "Comercio no encontrado.",
 
@@ -634,5 +634,10 @@
   "contact_support": "Contactar con Soporte",
   "gift_cards_unavailable": "Las tarjetas de regalo están disponibles para comprar solo a través de Monero, Bitcoin y Litecoin en este momento",
   "introducing_cake_pay":  "¡Presentamos Cake Pay!",
-  "cake_pay_learn_more": "¡Compre y canjee tarjetas al instante en la aplicación!\n¡Desliza hacia la derecha para obtener más información!"
+  "cake_pay_learn_more": "¡Compre y canjee tarjetas al instante en la aplicación!\n¡Desliza hacia la derecha para obtener más información!",
+  "automatic": "Automático",
+  "fixed_pair_not_supported": "Este par fijo no es compatible con los intercambios seleccionados",
+  "variable_pair_not_supported": "Este par de variables no es compatible con los intercambios seleccionados",
+  "none_of_selected_providers_can_exchange": "Ninguno de los proveedores seleccionados puede realizar este intercambio",
+  "choose_one": "Elige uno"
 }

res/values/strings_fr.arb

@@ -364,7 +364,7 @@
 
 
   "trade_for_not_created" : "L'échange pour ${title} n'est pas créé.",
-  "trade_not_created" : "Échange non créé.",
+  "trade_not_created" : "Échange non créé",
   "trade_id_not_found" : "Échange ${tradeId} de ${title} introuvable.",
   "trade_not_found" : "Échange introuvable.",
 
@@ -632,5 +632,10 @@
   "contact_support": "Contacter l'assistance",
   "gift_cards_unavailable": "Les cartes-cadeaux ne sont disponibles à l'achat que via Monero, Bitcoin et Litecoin pour le moment",
   "introducing_cake_pay":  "Présentation de Cake Pay!",
-  "cake_pay_learn_more": "Achetez et échangez instantanément des cartes dans l'application !\nBalayez vers la droite pour en savoir plus !"
+  "cake_pay_learn_more": "Achetez et échangez instantanément des cartes dans l'application !\nBalayez vers la droite pour en savoir plus !",
+  "automatic": "Automatique",
+  "fixed_pair_not_supported": "Cette paire fixe n'est pas prise en charge avec les échanges sélectionnés",
+  "variable_pair_not_supported": "Cette paire de variables n'est pas prise en charge avec les échanges sélectionnés",
+  "none_of_selected_providers_can_exchange": "Aucun des prestataires sélectionnés ne peut effectuer cet échange",
+  "choose_one": "Choisissez-en un"
 }

res/values/strings_hi.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "के लिए व्यापार ${title} निर्मित नहीं है.",
-  "trade_not_created" : "व्यापार नहीं बनाया गया.",
+  "trade_not_created" : "व्यापार नहीं बनाया गया",
   "trade_id_not_found" : "व्यापार ${tradeId} of ${title} नहीं मिला.",
   "trade_not_found" : "व्यापार नहीं मिला",
 
@@ -634,5 +634,10 @@
   "contact_support": "सहायता से संपर्क करें",
   "gift_cards_unavailable": "उपहार कार्ड इस समय केवल मोनेरो, बिटकॉइन और लिटकोइन के माध्यम से खरीदने के लिए उपलब्ध हैं",
   "introducing_cake_pay":  "परिचय Cake Pay!",
-  "cake_pay_learn_more": "ऐप में तुरंत कार्ड खरीदें और रिडीम करें!\nअधिक जानने के लिए दाएं स्वाइप करें!"
+  "cake_pay_learn_more": "ऐप में तुरंत कार्ड खरीदें और रिडीम करें!\nअधिक जानने के लिए दाएं स्वाइप करें!",
+  "automatic": "स्वचालित",
+  "fixed_pair_not_supported": "यह निश्चित जोड़ी चयनित एक्सचेंजों के साथ समर्थित नहीं है",
+  "variable_pair_not_supported": "यह परिवर्तनीय जोड़ी चयनित एक्सचेंजों के साथ समर्थित नहीं है",
+  "none_of_selected_providers_can_exchange": "चयनित प्रदाताओं में से कोई भी इस एक्सचेंज को नहीं बना सकता",
+  "choose_one": "एक का चयन"
 }

res/values/strings_hr.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "Razmjena za ${title} nije izrađena.",
-  "trade_not_created" : "Razmjena nije izrađena.",
+  "trade_not_created" : "Razmjena nije izrađena",
   "trade_id_not_found" : "Razmjena ${tradeId} za ${title} nije pronađena.",
   "trade_not_found" : "Razmjena nije pronađena.",
 
@@ -634,5 +634,10 @@
   "contact_support": "Kontaktirajte podršku",
   "gift_cards_unavailable": "Poklon kartice trenutno su dostupne za kupnju samo putem Monera, Bitcoina i Litecoina",
   "introducing_cake_pay":  "Predstavljamo Cake Pay!",
-  "cake_pay_learn_more": "Odmah kupite i iskoristite kartice u aplikaciji!\nPrijeđite prstom udesno da biste saznali više!"
+  "cake_pay_learn_more": "Odmah kupite i iskoristite kartice u aplikaciji!\nPrijeđite prstom udesno da biste saznali više!",
+  "automatic": "Automatski",
+  "fixed_pair_not_supported": "Ovaj fiksni par nije podržan s odabranim burzama",
+  "variable_pair_not_supported": "Ovaj par varijabli nije podržan s odabranim burzama",
+  "none_of_selected_providers_can_exchange": "Niti jedan od odabranih pružatelja usluga ne može izvršiti ovu razmjenu",
+  "choose_one": "Izaberi jedan"
 }

res/values/strings_it.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "Lo scambio per ${title} non è stato creato.",
-  "trade_not_created" : "Scambio non creato.",
+  "trade_not_created" : "Scambio non creato",
   "trade_id_not_found" : "Scambio ${tradeId} di ${title} not trovato.",
   "trade_not_found" : "Scambio non trovato.",
 
@@ -634,5 +634,10 @@
   "contact_support": "Contatta l'assistenza",
   "gift_cards_unavailable": "Le carte regalo sono disponibili per l'acquisto solo tramite Monero, Bitcoin e Litecoin in questo momento",
   "introducing_cake_pay":  "Presentazione di Cake Pay!",
-  "cake_pay_learn_more": "Acquista e riscatta istantaneamente le carte nell'app!\nScorri verso destra per saperne di più!"
+  "cake_pay_learn_more": "Acquista e riscatta istantaneamente le carte nell'app!\nScorri verso destra per saperne di più!",
+  "automatic": "Automatico",
+  "fixed_pair_not_supported": "Questa coppia fissa non è supportata con gli scambi selezionati",
+  "variable_pair_not_supported": "Questa coppia di variabili non è supportata con gli scambi selezionati",
+  "none_of_selected_providers_can_exchange": "Nessuno dei fornitori selezionati può effettuare questo scambio",
+  "choose_one": "Scegline uno"
 }

res/values/strings_ja.arb

@@ -612,21 +612,21 @@
   "cards": "カード",
   "active": "アクティブ",
   "redeemed": "償還",
-  "gift_card_balance_note": "残高が残っているギフトカードがここに表示されます",  
+  "gift_card_balance_note": "残高が残っているギフトカードがここに表示されます",
-  "gift_card_redeemed_note": "利用したギフトカードがここに表示されます",  
+  "gift_card_redeemed_note": "利用したギフトカードがここに表示されます",
-  "logout": "ログアウト",  
+  "logout": "ログアウト",
-  "add_tip": "ヒントを追加",  
+  "add_tip": "ヒントを追加",
-  "percentageOf": "of ${amount}",  
+  "percentageOf": "of ${amount}",
-  "is_percentage": "is",  
+  "is_percentage": "is",
-  "search_category": "検索カテゴリ",  
+  "search_category": "検索カテゴリ",
-  "mark_as_redeemed": "償還済みとしてマーク",  
+  "mark_as_redeemed": "償還済みとしてマーク",
-  "more_options": "その他のオプション",  
+  "more_options": "その他のオプション",
-  "awaiting_payment_confirmation": "支払い確認を待っています",  
+  "awaiting_payment_confirmation": "支払い確認を待っています",
-  "transaction_sent_notice": "1分経っても画面が進まない場合は、ブロックエクスプローラーとメールアドレスを確認してください。",  
+  "transaction_sent_notice": "1分経っても画面が進まない場合は、ブロックエクスプローラーとメールアドレスを確認してください。",
-  "agree": "同意する",  
+  "agree": "同意する",
-  "in_store": "インストア",  
+  "in_store": "インストア",
-  "generated_gift_card": "ギフトカードの生成",  
+  "generated_gift_card": "ギフトカードの生成",
-  "payment_was_received": "お支払いを受け取りました。",  
+  "payment_was_received": "お支払いを受け取りました。",
   "proceed_after_one_minute": "1分経っても画面が進まない場合は、メールを確認してください。",
   "order_id": "注文ID",
   "gift_card_is_generated": "ギフトカードが生成されます",
@@ -634,5 +634,10 @@
   "contact_support": "サポートに連絡する",
   "gift_cards_unavailable": "現時点では、ギフトカードはMonero、Bitcoin、Litecoinからのみ購入できます。",
   "introducing_cake_pay":  "序章Cake Pay！",
-  "cake_pay_learn_more": "アプリですぐにカードを購入して引き換えましょう！\n右にスワイプして詳細をご覧ください。"
+  "cake_pay_learn_more": "アプリですぐにカードを購入して引き換えましょう！\n右にスワイプして詳細をご覧ください。",
+  "automatic": "自動",
+  "fixed_pair_not_supported": "この固定ペアは、選択したエクスチェンジではサポートされていません",
+  "variable_pair_not_supported": "この変数ペアは、選択した取引所ではサポートされていません",
+  "none_of_selected_providers_can_exchange": "選択したプロバイダーはいずれもこの交換を行うことができません",
+  "choose_one": "1 つ選択してください"
 }

res/values/strings_ko.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "거래 ${title} 생성되지 않습니다.",
-  "trade_not_created" : "거래가 생성되지 않았습니다.",
+  "trade_not_created" : "거래가 생성되지 않았습니다",
   "trade_id_not_found" : "무역 ${tradeId} 의 ${title} 찾을 수 없습니다.",
   "trade_not_found" : "거래를 찾을 수 없습니다.",
 
@@ -634,5 +634,10 @@
   "contact_support": "지원팀에 문의",
   "gift_cards_unavailable": "기프트 카드는 현재 Monero, Bitcoin 및 Litecoin을 통해서만 구매할 수 있습니다.",
   "introducing_cake_pay":  "소개 Cake Pay!",
-  "cake_pay_learn_more": "앱에서 즉시 카드를 구매하고 사용하세요!\n자세히 알아보려면 오른쪽으로 스와이프하세요!"
+  "cake_pay_learn_more": "앱에서 즉시 카드를 구매하고 사용하세요!\n자세히 알아보려면 오른쪽으로 스와이프하세요!",
+  "automatic": "자동적 인",
+  "fixed_pair_not_supported": "이 고정 쌍은 선택한 교환에서 지원되지 않습니다.",
+  "variable_pair_not_supported": "이 변수 쌍은 선택한 교환에서 지원되지 않습니다.",
+  "none_of_selected_providers_can_exchange": "선택한 공급자 중 누구도 이 교환을 할 수 없습니다.",
+  "choose_one": "하나 선택"
 }

res/values/strings_nl.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "Ruilen voor ${title} is niet gemaakt.",
-  "trade_not_created" : "Handel niet gecreëerd.",
+  "trade_not_created" : "Handel niet gecreëerd",
   "trade_id_not_found" : "Handel ${tradeId} van ${title} niet gevonden.",
   "trade_not_found" : "Handel niet gevonden.",
 
@@ -533,7 +533,7 @@
   "search_language": "Zoektaal",
   "search_currency": "Zoek valuta",
   "new_template" : "Nieuwe sjabloon",
-  "electrum_address_disclaimer": "We generate new addresses each time you use one, but previous addresses continue to work",
+  "electrum_address_disclaimer": "We genereren nieuwe adressen elke keer dat u er een gebruikt, maar eerdere adressen blijven werken",
   "wallet_name_exists": "Portemonnee met die naam bestaat al",
   "market_place": "Marktplaats",
   "cake_pay_title": "Cake Pay-cadeaubonnen",
@@ -634,5 +634,10 @@
   "contact_support": "Contact opnemen met ondersteuning",
   "gift_cards_unavailable": "Cadeaubonnen kunnen momenteel alleen worden gekocht via Monero, Bitcoin en Litecoin",
   "introducing_cake_pay":  "Introductie van Cake Pay!",
-  "cake_pay_learn_more": "Koop en wissel direct kaarten in de app!\nSwipe naar rechts voor meer informatie!"
+  "cake_pay_learn_more": "Koop en wissel direct kaarten in de app!\nSwipe naar rechts voor meer informatie!",
+  "automatic": "automatisch",
+  "fixed_pair_not_supported": "Dit vaste paar wordt niet ondersteund bij de geselecteerde exchanges",
+  "variable_pair_not_supported": "Dit variabelenpaar wordt niet ondersteund met de geselecteerde uitwisselingen",
+  "none_of_selected_providers_can_exchange": "Geen van de geselecteerde providers kan deze uitwisseling maken",
+  "choose_one": "Kies er een"
 }

res/values/strings_pl.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "Zamienić się za ${title} nie jest tworzony.",
-  "trade_not_created" : "Handel nie utworzony.",
+  "trade_not_created" : "Handel nie utworzony",
   "trade_id_not_found" : "Handel ${tradeId} of ${title} nie znaleziono.",
   "trade_not_found" : "Nie znaleziono handlu.",
 
@@ -634,5 +634,10 @@
   "contact_support": "Skontaktuj się z pomocą techniczną",
   "gift_cards_unavailable": "Karty podarunkowe można obecnie kupić tylko za pośrednictwem Monero, Bitcoin i Litecoin",
   "introducing_cake_pay":  "Przedstawiamy Ciasto Pay!",
-  "cake_pay_learn_more": "Natychmiast kupuj i realizuj karty w aplikacji!\nPrzesuń w prawo, aby dowiedzieć się więcej!"
+  "cake_pay_learn_more": "Natychmiast kupuj i realizuj karty w aplikacji!\nPrzesuń w prawo, aby dowiedzieć się więcej!",
+  "automatic": "Automatyczny",
+  "fixed_pair_not_supported": "Ta stała para nie jest obsługiwana na wybranych giełdach",
+  "variable_pair_not_supported": "Ta para zmiennych nie jest obsługiwana na wybranych giełdach",
+  "none_of_selected_providers_can_exchange": "Żaden z wybranych dostawców nie może dokonać tej wymiany",
+  "choose_one": "Wybierz jeden"
 }

res/values/strings_pt.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "A troca por ${title} não foi criada.",
-  "trade_not_created" : "Troca não criada.",
+  "trade_not_created" : "Troca não criada",
   "trade_id_not_found" : "A troca ${tradeId} de ${title} não foi encontrada.",
   "trade_not_found" : "Troca não encontrada.",
 
@@ -634,5 +634,10 @@
   "contact_support": "Contatar Suporte",
   "gift_cards_unavailable": "Os cartões-presente estão disponíveis para compra apenas através do Monero, Bitcoin e Litecoin no momento",
   "introducing_cake_pay":  "Apresentando o Cake Pay!",
-  "cake_pay_learn_more": "Compre e resgate cartões instantaneamente no aplicativo!\nDeslize para a direita para saber mais!"
+  "cake_pay_learn_more": "Compre e resgate cartões instantaneamente no aplicativo!\nDeslize para a direita para saber mais!",
+  "automatic": "Automático",
+  "fixed_pair_not_supported": "Este par fixo não é compatível com as exchanges selecionadas",
+  "variable_pair_not_supported": "Este par de variáveis não é compatível com as trocas selecionadas",
+  "none_of_selected_providers_can_exchange": "Nenhum dos provedores selecionados pode fazer esta troca",
+  "choose_one": "Escolha um"
 }

res/values/strings_ru.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "Сделка для ${title} не создана.",
-  "trade_not_created" : "Сделка не создана.",
+  "trade_not_created" : "Сделка не создана",
   "trade_id_not_found" : "Сделка ${tradeId} ${title} не найдена.",
   "trade_not_found" : "Trade not found.",
 
@@ -634,5 +634,10 @@
   "contact_support": "Связаться со службой поддержки",
   "gift_cards_unavailable": "В настоящее время подарочные карты можно приобрести только через Monero, Bitcoin и Litecoin.",
   "introducing_cake_pay":  "Представляем Cake Pay!",
-  "cake_pay_learn_more": "Мгновенно покупайте и погашайте карты в приложении!\nПроведите вправо, чтобы узнать больше!"
+  "cake_pay_learn_more": "Мгновенно покупайте и погашайте карты в приложении!\nПроведите вправо, чтобы узнать больше!",
+  "automatic": "автоматический",
+  "fixed_pair_not_supported": "Эта фиксированная пара не поддерживается выбранными биржами.",
+  "variable_pair_not_supported": "Эта пара переменных не поддерживается выбранными биржами.",
+  "none_of_selected_providers_can_exchange": "Ни один из выбранных провайдеров не может совершить этот обмен",
+  "choose_one": "Выбери один"
 }

res/values/strings_uk.arb

@@ -365,7 +365,7 @@
 
 
   "trade_for_not_created" : "Операція для ${title} не створена.",
-  "trade_not_created" : "Операція не створена.",
+  "trade_not_created" : "Операція не створена",
   "trade_id_not_found" : "Операція ${tradeId} ${title} не знайдена.",
   "trade_not_found" : "Операція не знайдена.",
 
@@ -633,5 +633,10 @@
   "contact_support": "Звернутися до служби підтримки",
   "gift_cards_unavailable": "Наразі подарункові картки можна придбати лише через Monero, Bitcoin і Litecoin",
   "introducing_cake_pay":  "Представляємо Cake Pay!",
-  "cake_pay_learn_more": "Миттєва купівля та погашення карток в додатку!\nПроведіть праворуч, щоб дізнатися більше!"
+  "cake_pay_learn_more": "Миттєва купівля та погашення карток в додатку!\nПроведіть праворуч, щоб дізнатися більше!",
+  "automatic": "Автоматичний",
+  "fixed_pair_not_supported": "Ця фіксована пара не підтримується вибраними біржами",
+  "variable_pair_not_supported": "Ця пара змінних не підтримується вибраними біржами",
+  "none_of_selected_providers_can_exchange": "Жоден із вибраних провайдерів не може здійснити цей обмін",
+  "choose_one": "Вибери один"
 }

res/values/strings_zh.arb

@@ -366,7 +366,7 @@
 
 
   "trade_for_not_created" : "交易 ${title} 未创建.",
-  "trade_not_created" : "未建立交易.",
+  "trade_not_created" : "未建立交易",
   "trade_id_not_found" : "交易方式 ${tradeId} 的 ${title} 未找到.",
   "trade_not_found" : "找不到交易.",
 
@@ -632,5 +632,10 @@
   "contact_support": "联系支持",
   "gift_cards_unavailable": "目前只能通过门罗币、比特币和莱特币购买礼品卡",
   "introducing_cake_pay":  "介绍 Cake Pay!",
-  "cake_pay_learn_more": "立即在应用程序中购买和兑换卡！\n向右滑动了解更多！"
+  "cake_pay_learn_more": "立即在应用程序中购买和兑换卡！\n向右滑动了解更多！",
+  "automatic": "自动的",
+  "fixed_pair_not_supported": "所选交易所不支持此固定货币对",
+  "variable_pair_not_supported": "所选交易所不支持此变量对",
+  "none_of_selected_providers_can_exchange": "选定的供应商都不能进行此交换",
+  "choose_one": "选一个"
 }