initial whirlpool integration

src/main/java/com/sparrowwallet/sparrow/AppController.java

@@ -30,6 +30,7 @@ import com.sparrowwallet.sparrow.transaction.TransactionData;
 import com.sparrowwallet.sparrow.transaction.TransactionView;
 import com.sparrowwallet.sparrow.wallet.WalletController;
 import com.sparrowwallet.sparrow.wallet.WalletForm;
+import com.sparrowwallet.sparrow.whirlpool.Whirlpool;
 import de.codecentric.centerdevice.MenuToolkit;
 import javafx.animation.*;
 import javafx.application.Platform;
@@ -819,13 +820,13 @@ public class AppController implements Initializable {
     private void openWallet(Storage storage, WalletBackupAndKey walletBackupAndKey, AppController appController, boolean forceSameWindow) {
         try {
             checkWalletNetwork(walletBackupAndKey.getWallet());
-            restorePublicKeysFromSeed(walletBackupAndKey.getWallet(), walletBackupAndKey.getKey());
+            restorePublicKeysFromSeed(storage, walletBackupAndKey.getWallet(), walletBackupAndKey.getKey());
             if(!walletBackupAndKey.getWallet().isValid()) {
                 throw new IllegalStateException("Wallet file is not valid.");
             }
             AppController walletAppController = appController.addWalletTabOrWindow(storage, walletBackupAndKey.getWallet(), walletBackupAndKey.getBackupWallet(), forceSameWindow);
-            for(Map.Entry<Storage, WalletBackupAndKey> entry : walletBackupAndKey.getChildWallets().entrySet()) {
-                openWallet(entry.getKey(), entry.getValue(), walletAppController, true);
+            for(Map.Entry<WalletBackupAndKey, Storage> entry : walletBackupAndKey.getChildWallets().entrySet()) {
+                openWallet(entry.getValue(), entry.getKey(), walletAppController, true);
             }
             Platform.runLater(() -> selectTab(walletBackupAndKey.getWallet()));
         } catch(Exception e) {
@@ -842,7 +843,7 @@ public class AppController implements Initializable {
         }
     }
 
-    private void restorePublicKeysFromSeed(Wallet wallet, Key key) throws MnemonicException {
+    private void restorePublicKeysFromSeed(Storage storage, Wallet wallet, Key key) throws MnemonicException {
         if(wallet.containsPrivateKeys()) {
             //Derive xpub and master fingerprint from seed, potentially with passphrase
             Wallet copy = wallet.copy();
@@ -870,6 +871,12 @@ public class AppController implements Initializable {
                 copy.decrypt(key);
             }
 
+            if(wallet.isWhirlpoolMasterWallet()) {
+                String walletId = storage.getWalletId(wallet);
+                Whirlpool whirlpool = AppServices.get().getWhirlpool(walletId);
+                whirlpool.setHDWallet(copy);
+            }
+
             for(int i = 0; i < wallet.getKeystores().size(); i++) {
                 Keystore keystore = wallet.getKeystores().get(i);
                 if(keystore.hasSeed()) {
@@ -985,13 +992,13 @@ public class AppController implements Initializable {
                     storage.setEncryptionPubKey(Storage.NO_PASSWORD_KEY);
                     storage.saveWallet(wallet);
                     checkWalletNetwork(wallet);
-                    restorePublicKeysFromSeed(wallet, null);
+                    restorePublicKeysFromSeed(storage, wallet, null);
                     addWalletTabOrWindow(storage, wallet, null, false);
 
                     for(Wallet childWallet : wallet.getChildWallets()) {
                         storage.saveWallet(childWallet);
                         checkWalletNetwork(childWallet);
-                        restorePublicKeysFromSeed(childWallet, null);
+                        restorePublicKeysFromSeed(storage, childWallet, null);
                         addWalletTabOrWindow(storage, childWallet, null, false);
                     }
                     Platform.runLater(() -> selectTab(wallet));
@@ -1012,14 +1019,14 @@ public class AppController implements Initializable {
                         storage.setEncryptionPubKey(encryptionPubKey);
                         storage.saveWallet(wallet);
                         checkWalletNetwork(wallet);
-                        restorePublicKeysFromSeed(wallet, key);
+                        restorePublicKeysFromSeed(storage, wallet, key);
                         addWalletTabOrWindow(storage, wallet, null, false);
 
                         for(Wallet childWallet : wallet.getChildWallets()) {
                             childWallet.encrypt(key);
                             storage.saveWallet(childWallet);
                             checkWalletNetwork(childWallet);
-                            restorePublicKeysFromSeed(childWallet, key);
+                            restorePublicKeysFromSeed(storage, childWallet, key);
                             addWalletTabOrWindow(storage, childWallet, null, false);
                         }
                         Platform.runLater(() -> selectTab(wallet));
@@ -1184,8 +1191,8 @@ public class AppController implements Initializable {
                     WalletTabData walletTabData = (WalletTabData)tabData;
                     if(walletTabData.getWallet() == wallet.getMasterWallet()) {
                         TabPane subTabs = (TabPane)walletTab.getContent();
-                        subTabs.getStyleClass().remove("master-only");
                         addWalletSubTab(subTabs, storage, wallet, backupWallet);
+                        Platform.runLater(() -> subTabs.getStyleClass().remove("master-only"));
                     }
                 }
             }
@@ -1194,7 +1201,7 @@ public class AppController implements Initializable {
 
     public WalletForm addWalletSubTab(TabPane subTabs, Storage storage, Wallet wallet, Wallet backupWallet) {
         try {
-            Tab subTab = new Tab(wallet.getName());
+            Tab subTab = new Tab(wallet.isMasterWallet() ? getAutomaticName(wallet) : wallet.getName());
             subTab.setClosable(false);
             FXMLLoader walletLoader = new FXMLLoader(getClass().getResource("wallet/wallet.fxml"));
             subTab.setContent(walletLoader.load());
@@ -1219,6 +1226,11 @@ public class AppController implements Initializable {
         }
     }
 
+    private String getAutomaticName(Wallet wallet) {
+        int account = wallet.getAccountIndex();
+        return account < 0 ? wallet.getName() : "Account #" + account;
+    }
+
     public WalletForm getSelectedWalletForm() {
         Tab selectedTab = tabs.getSelectionModel().getSelectedItem();
         TabData tabData = (TabData)selectedTab.getUserData();
@@ -2016,4 +2028,14 @@ public class AppController implements Initializable {
     public void recieveAction(ReceiveActionEvent event) {
         selectTab(event.getWallet());
     }
+
+    @Subscribe
+    public void childWalletAdded(ChildWalletAddedEvent event) {
+        Storage storage = AppServices.get().getOpenWallets().get(event.getWallet());
+        if(storage == null) {
+            throw new IllegalStateException("Cannot find storage for master wallet");
+        }
+
+        addWalletTab(storage, event.getChildWallet(), null);
+    }
 }

src/main/java/com/sparrowwallet/sparrow/AppServices.java

@@ -2,8 +2,10 @@ package com.sparrowwallet.sparrow;
 
 import com.google.common.eventbus.Subscribe;
 import com.google.common.net.HostAndPort;
+import com.samourai.whirlpool.client.wallet.WhirlpoolEventService;
 import com.sparrowwallet.drongo.Network;
 import com.sparrowwallet.drongo.address.Address;
+import com.sparrowwallet.drongo.protocol.BlockHeader;
 import com.sparrowwallet.drongo.protocol.ScriptType;
 import com.sparrowwallet.drongo.protocol.Transaction;
 import com.sparrowwallet.drongo.psbt.PSBT;
@@ -15,6 +17,7 @@ import com.sparrowwallet.sparrow.control.TrayManager;
 import com.sparrowwallet.sparrow.event.*;
 import com.sparrowwallet.sparrow.io.*;
 import com.sparrowwallet.sparrow.net.*;
+import com.sparrowwallet.sparrow.whirlpool.Whirlpool;
 import javafx.application.Platform;
 import javafx.beans.property.BooleanProperty;
 import javafx.beans.property.SimpleBooleanProperty;
@@ -89,8 +92,12 @@ public class AppServices {
 
     private TorService torService;
 
+    private final Map<String, Whirlpool> whirlpoolMap = new HashMap<>();
+
     private static Integer currentBlockHeight;
 
+    private static BlockHeader latestBlockHeader;
+
     private static Map<Integer, Double> targetBlockFeeRates;
 
     private static final Map<Date, Set<MempoolRateSize>> mempoolHistogram = new TreeMap<>();
@@ -445,6 +452,37 @@ public class AppServices {
         return application;
     }
 
+    public Whirlpool getWhirlpool(String walletId) {
+        Whirlpool whirlpool = whirlpoolMap.get(walletId);
+        if(whirlpool == null) {
+            HostAndPort torProxy = AppServices.isTorRunning() ? HostAndPort.fromParts("localhost", TorService.PROXY_PORT) : (Config.get().getProxyServer().isEmpty() || !Config.get().isUseProxy() ? null : HostAndPort.fromString(Config.get().getProxyServer()));
+            whirlpool = new Whirlpool(Network.get(), torProxy, Config.get().getScode(), 1, 15);
+            whirlpoolMap.put(walletId, whirlpool);
+        }
+
+        return whirlpool;
+    }
+
+    private void startAllWhirlpool() {
+        for(Whirlpool whirlpool : whirlpoolMap.values().stream().filter(whirlpool -> whirlpool.hasWallet() && !whirlpool.isStarted()).collect(Collectors.toList())) {
+            Whirlpool.StartupService startupService = new Whirlpool.StartupService(whirlpool);
+            startupService.setOnFailed(workerStateEvent -> {
+                log.error("Failed to start whirlpool", workerStateEvent.getSource().getException());
+            });
+            startupService.start();
+        }
+    }
+
+    private void stopAllWhirlpool() {
+        for(Whirlpool whirlpool : whirlpoolMap.values().stream().filter(Whirlpool::isStarted).collect(Collectors.toList())) {
+            Whirlpool.ShutdownService shutdownService = new Whirlpool.ShutdownService(whirlpool);
+            shutdownService.setOnFailed(workerStateEvent -> {
+                log.error("Failed to stop whirlpool", workerStateEvent.getSource().getException());
+            });
+            shutdownService.start();
+        }
+    }
+
     public void minimizeStage(Stage stage) {
         if(trayManager == null) {
             trayManager = new TrayManager();
@@ -503,6 +541,10 @@ public class AppServices {
         return currentBlockHeight;
     }
 
+    public static BlockHeader getLatestBlockHeader() {
+        return latestBlockHeader;
+    }
+
     public static Map<Integer, Double> getTargetBlockFeeRates() {
         return targetBlockFeeRates;
     }
@@ -776,6 +818,13 @@ public class AppServices {
         targetBlockFeeRates = event.getTargetBlockFeeRates();
         addMempoolRateSizes(event.getMempoolRateSizes());
         minimumRelayFeeRate = event.getMinimumRelayFeeRate();
+        latestBlockHeader = event.getBlockHeader();
+        startAllWhirlpool();
+    }
+
+    @Subscribe
+    public void disconnection(DisconnectionEvent event) {
+        stopAllWhirlpool();
     }
 
     @Subscribe
@@ -786,6 +835,7 @@ public class AppServices {
     @Subscribe
     public void newBlock(NewBlockEvent event) {
         currentBlockHeight = event.getHeight();
+        latestBlockHeader = event.getBlockHeader();
         String status = "Updating to new block height " + event.getHeight();
         EventManager.get().post(new StatusEvent(status));
     }
@@ -901,6 +951,40 @@ public class AppServices {
     @Subscribe
     public void walletOpening(WalletOpeningEvent event) {
         restartBwt(event.getWallet());
+
+        String walletId = event.getStorage().getWalletId(event.getWallet());
+        Whirlpool whirlpool = whirlpoolMap.get(walletId);
+        if(whirlpool != null && !whirlpool.isStarted() && isConnected()) {
+            Whirlpool.StartupService startupService = new Whirlpool.StartupService(whirlpool);
+            startupService.setOnFailed(workerStateEvent -> {
+                log.error("Failed to start whirlpool", workerStateEvent.getSource().getException());
+            });
+            startupService.start();
+        }
+    }
+
+    @Subscribe
+    public void walletTabsClosed(WalletTabsClosedEvent event) {
+        for(WalletTabData walletTabData : event.getClosedWalletTabData()) {
+            String walletId = walletTabData.getStorage().getWalletId(walletTabData.getWallet());
+            Whirlpool whirlpool = whirlpoolMap.remove(walletId);
+            if(whirlpool != null) {
+                if(whirlpool.isStarted()) {
+                    Whirlpool.ShutdownService shutdownService = new Whirlpool.ShutdownService(whirlpool);
+                    shutdownService.setOnSucceeded(workerStateEvent -> {
+                        WhirlpoolEventService.getInstance().unregister(whirlpool);
+                    });
+                    shutdownService.setOnFailed(workerStateEvent -> {
+                        log.error("Failed to stop whirlpool", workerStateEvent.getSource().getException());
+                    });
+                    shutdownService.start();
+                } else {
+                    //Ensure http clients are shutdown
+                    whirlpool.shutdown();
+                    WhirlpoolEventService.getInstance().unregister(whirlpool);
+                }
+            }
+        }
     }
 
     private void restartBwt(Wallet wallet) {

src/main/java/com/sparrowwallet/sparrow/control/ServiceProgressDialog.java

@@ -0,0 +1,25 @@
+package com.sparrowwallet.sparrow.control;
+
+import com.sparrowwallet.sparrow.AppServices;
+import javafx.concurrent.Worker;
+import javafx.scene.control.DialogPane;
+import javafx.scene.image.Image;
+import javafx.scene.image.ImageView;
+import org.controlsfx.dialog.ProgressDialog;
+
+public class ServiceProgressDialog extends ProgressDialog {
+    public ServiceProgressDialog(String title, String header, String imagePath, Worker<?> worker) {
+        super(worker);
+
+        final DialogPane dialogPane = getDialogPane();
+        dialogPane.getStylesheets().add(AppServices.class.getResource("general.css").toExternalForm());
+        AppServices.setStageIcon(dialogPane.getScene().getWindow());
+
+        setTitle(title);
+        setHeaderText(header);
+
+        dialogPane.getStyleClass().remove("progress-dialog");
+        Image image = new Image(imagePath);
+        dialogPane.setGraphic(new ImageView(image));
+    }
+}

src/main/java/com/sparrowwallet/sparrow/control/TransactionDiagram.java

@@ -377,12 +377,13 @@ public class TransactionDiagram extends GridPane {
         outputsBox.getChildren().add(createSpacer());
 
         for(Payment payment : displayedPayments) {
-            boolean isConsolidation = walletTx.isConsolidationSend(payment);
-            String recipientDesc = payment instanceof AdditionalPayment ? payment.getLabel() : payment.getAddress().toString().substring(0, 8) + "...";
-            Label recipientLabel = new Label(recipientDesc, isConsolidation ? getConsolidationGlyph() : getPaymentGlyph());
+            Glyph outputGlyph = getOutputGlyph(payment);
+            boolean labelledPayment = outputGlyph.getStyleClass().stream().anyMatch(style -> List.of("premix-icon", "badbank-icon", "whirlpoolfee-icon").contains(style)) || payment instanceof AdditionalPayment;
+            String recipientDesc = labelledPayment ? payment.getLabel() : payment.getAddress().toString().substring(0, 8) + "...";
+            Label recipientLabel = new Label(recipientDesc, outputGlyph);
             recipientLabel.getStyleClass().add("output-label");
-            recipientLabel.getStyleClass().add(payment instanceof AdditionalPayment ? "additional-label" : "recipient-label");
-            Tooltip recipientTooltip = new Tooltip((isConsolidation ? "Consolidate " : "Pay ") + getSatsValue(payment.getAmount()) + " sats to " + (payment instanceof AdditionalPayment ? "\n" + payment : payment.getLabel() + "\n" + payment.getAddress().toString()));
+            recipientLabel.getStyleClass().add(labelledPayment ? "payment-label" : "recipient-label");
+            Tooltip recipientTooltip = new Tooltip((walletTx.isConsolidationSend(payment) ? "Consolidate " : "Pay ") + getSatsValue(payment.getAmount()) + " sats to " + (payment instanceof AdditionalPayment ? "\n" + payment : payment.getLabel() + "\n" + payment.getAddress().toString()));
             recipientTooltip.getStyleClass().add("recipient-label");
             recipientTooltip.setShowDelay(new Duration(TOOLTIP_SHOW_DELAY));
             recipientLabel.setTooltip(recipientTooltip);
@@ -467,6 +468,22 @@ public class TransactionDiagram extends GridPane {
         return spacer;
     }
 
+    public Glyph getOutputGlyph(Payment payment) {
+        if(walletTx.isConsolidationSend(payment)) {
+            return getConsolidationGlyph();
+        } else if(walletTx.isPremixSend(payment)) {
+            return getPremixGlyph();
+        } else if(walletTx.isBadbankSend(payment)) {
+            return getBadbankGlyph();
+        } else if(payment.getType().equals(Payment.Type.WHIRLPOOL_FEE)) {
+            return getWhirlpoolFeeGlyph();
+        } else if(payment instanceof AdditionalPayment) {
+            return ((AdditionalPayment)payment).getOutputGlyph(this);
+        }
+
+        return getPaymentGlyph();
+    }
+
     public static Glyph getExcludeGlyph() {
         Glyph excludeGlyph = new Glyph(FontAwesome5.FONT_NAME, FontAwesome5.Glyph.TIMES_CIRCLE);
         excludeGlyph.getStyleClass().add("exclude-utxo");
@@ -488,6 +505,27 @@ public class TransactionDiagram extends GridPane {
         return consolidationGlyph;
     }
 
+    public static Glyph getPremixGlyph() {
+        Glyph premixGlyph = new Glyph(FontAwesome5.FONT_NAME, FontAwesome5.Glyph.RANDOM);
+        premixGlyph.getStyleClass().add("premix-icon");
+        premixGlyph.setFontSize(12);
+        return premixGlyph;
+    }
+
+    public static Glyph getBadbankGlyph() {
+        Glyph badbankGlyph = new Glyph(FontAwesome5.FONT_NAME, FontAwesome5.Glyph.BIOHAZARD);
+        badbankGlyph.getStyleClass().add("badbank-icon");
+        badbankGlyph.setFontSize(12);
+        return badbankGlyph;
+    }
+
+    public static Glyph getWhirlpoolFeeGlyph() {
+        Glyph whirlpoolFeeGlyph = new Glyph(FontAwesome5.FONT_NAME, FontAwesome5.Glyph.HAND_HOLDING_WATER);
+        whirlpoolFeeGlyph.getStyleClass().add("whirlpoolfee-icon");
+        whirlpoolFeeGlyph.setFontSize(12);
+        return whirlpoolFeeGlyph;
+    }
+
     public static Glyph getTxoGlyph() {
         return getChangeGlyph();
     }
@@ -578,6 +616,20 @@ public class TransactionDiagram extends GridPane {
             this.additionalPayments = additionalPayments;
         }
 
+        public Glyph getOutputGlyph(TransactionDiagram transactionDiagram) {
+            Glyph glyph = null;
+            for(Payment payment : additionalPayments) {
+                Glyph paymentGlyph = transactionDiagram.getOutputGlyph(payment);
+                if(glyph != null && !paymentGlyph.getStyleClass().equals(glyph.getStyleClass())) {
+                    return getPaymentGlyph();
+                }
+
+                glyph = paymentGlyph;
+            }
+
+            return glyph;
+        }
+
         public String toString() {
             return additionalPayments.stream().map(payment -> payment.getAddress().toString()).collect(Collectors.joining("\n"));
         }

src/main/java/com/sparrowwallet/sparrow/event/ChildWalletAddedEvent.java

@@ -0,0 +1,27 @@
+package com.sparrowwallet.sparrow.event;
+
+import com.sparrowwallet.drongo.wallet.Wallet;
+import com.sparrowwallet.sparrow.io.Storage;
+
+public class ChildWalletAddedEvent extends WalletChangedEvent {
+    private final Storage storage;
+    private final Wallet childWallet;
+
+    public ChildWalletAddedEvent(Storage storage, Wallet masterWallet, Wallet childWallet) {
+        super(masterWallet);
+        this.storage = storage;
+        this.childWallet = childWallet;
+    }
+
+    public Storage getStorage() {
+        return storage;
+    }
+
+    public Wallet getChildWallet() {
+        return childWallet;
+    }
+
+    public String getMasterWalletId() {
+        return storage.getWalletId(getWallet());
+    }
+}

src/main/java/com/sparrowwallet/sparrow/event/SpendUtxoEvent.java

@@ -1,5 +1,6 @@
 package com.sparrowwallet.sparrow.event;
 
+import com.samourai.whirlpool.client.whirlpool.beans.Pool;
 import com.sparrowwallet.drongo.wallet.BlockTransactionHashIndex;
 import com.sparrowwallet.drongo.wallet.Payment;
 import com.sparrowwallet.drongo.wallet.Wallet;
@@ -12,6 +13,7 @@ public class SpendUtxoEvent {
     private final List<Payment> payments;
     private final Long fee;
     private final boolean includeSpentMempoolOutputs;
+    private final Pool pool;
 
     public SpendUtxoEvent(Wallet wallet, List<BlockTransactionHashIndex> utxos) {
         this(wallet, utxos, null, null, false);
@@ -23,6 +25,16 @@ public class SpendUtxoEvent {
         this.payments = payments;
         this.fee = fee;
         this.includeSpentMempoolOutputs = includeSpentMempoolOutputs;
+        this.pool = null;
+    }
+
+    public SpendUtxoEvent(Wallet wallet, List<BlockTransactionHashIndex> utxos, List<Payment> payments, Long fee, Pool pool) {
+        this.wallet = wallet;
+        this.utxos = utxos;
+        this.payments = payments;
+        this.fee = fee;
+        this.includeSpentMempoolOutputs = false;
+        this.pool = pool;
     }
 
     public Wallet getWallet() {
@@ -44,4 +56,8 @@ public class SpendUtxoEvent {
     public boolean isIncludeSpentMempoolOutputs() {
         return includeSpentMempoolOutputs;
     }
+
+    public Pool getPool() {
+        return pool;
+    }
 }

src/main/java/com/sparrowwallet/sparrow/glyphfont/FontAwesome5.java

@@ -20,6 +20,7 @@ public class FontAwesome5 extends GlyphFont {
         ARROW_DOWN('\uf063'),
         ARROW_UP('\uf062'),
         BAN('\uf05e'),
+        BIOHAZARD('\uf780'),
         BTC('\uf15a'),
         CAMERA('\uf030'),
         CHECK_CIRCLE('\uf058'),
@@ -35,6 +36,7 @@ public class FontAwesome5 extends GlyphFont {
         FILE_CSV('\uf6dd'),
         HAND_HOLDING('\uf4bd'),
         HAND_HOLDING_MEDICAL('\ue05c'),
+        HAND_HOLDING_WATER('\uf4c1'),
         HISTORY('\uf1da'),
         KEY('\uf084'),
         LAPTOP('\uf109'),

src/main/java/com/sparrowwallet/sparrow/io/Config.java

@@ -11,8 +11,6 @@ import org.slf4j.LoggerFactory;
 
 import java.io.*;
 import java.lang.reflect.Type;
-import java.nio.file.Files;
-import java.nio.file.attribute.PosixFilePermissions;
 import java.util.Arrays;
 import java.util.Currency;
 import java.util.List;
@@ -59,6 +57,7 @@ public class Config {
     private File electrumServerCert;
     private boolean useProxy;
     private String proxyServer;
+    private String scode;
 
     private static Config INSTANCE;
 
@@ -459,6 +458,15 @@ public class Config {
         flush();
     }
 
+    public String getScode() {
+        return scode;
+    }
+
+    public void setScode(String scode) {
+        this.scode = scode;
+        flush();
+    }
+
     private synchronized void flush() {
         Gson gson = getGson();
         try {

src/main/java/com/sparrowwallet/sparrow/io/JsonPersistence.java

@@ -43,8 +43,8 @@ public class JsonPersistence implements Persistence {
             wallet = gson.fromJson(reader, Wallet.class);
         }
 
-        Map<Storage, WalletBackupAndKey> childWallets = loadChildWallets(storage, wallet, null);
-        wallet.setChildWallets(childWallets.values().stream().map(WalletBackupAndKey::getWallet).collect(Collectors.toList()));
+        Map<WalletBackupAndKey, Storage> childWallets = loadChildWallets(storage, wallet, null);
+        wallet.setChildWallets(childWallets.keySet().stream().map(WalletBackupAndKey::getWallet).collect(Collectors.toList()));
 
         File backupFile = storage.getTempBackup();
         Wallet backupWallet = backupFile == null ? null : loadWallet(backupFile, null);
@@ -68,8 +68,8 @@ public class JsonPersistence implements Persistence {
             wallet = gson.fromJson(reader, Wallet.class);
         }
 
-        Map<Storage, WalletBackupAndKey> childWallets = loadChildWallets(storage, wallet, encryptionKey);
-        wallet.setChildWallets(childWallets.values().stream().map(WalletBackupAndKey::getWallet).collect(Collectors.toList()));
+        Map<WalletBackupAndKey, Storage> childWallets = loadChildWallets(storage, wallet, encryptionKey);
+        wallet.setChildWallets(childWallets.keySet().stream().map(WalletBackupAndKey::getWallet).collect(Collectors.toList()));
 
         File backupFile = storage.getTempBackup();
         Wallet backupWallet = backupFile == null ? null : loadWallet(backupFile, encryptionKey);
@@ -77,16 +77,16 @@ public class JsonPersistence implements Persistence {
         return new WalletBackupAndKey(wallet, backupWallet, encryptionKey, keyDeriver, childWallets);
     }
 
-    private Map<Storage, WalletBackupAndKey> loadChildWallets(Storage storage, Wallet masterWallet, ECKey encryptionKey) throws IOException, StorageException {
+    private Map<WalletBackupAndKey, Storage> loadChildWallets(Storage storage, Wallet masterWallet, ECKey encryptionKey) throws IOException, StorageException {
         File[] walletFiles = getChildWalletFiles(storage.getWalletFile(), masterWallet);
-        Map<Storage, WalletBackupAndKey> childWallets = new LinkedHashMap<>();
+        Map<WalletBackupAndKey, Storage> childWallets = new TreeMap<>();
         for(File childFile : walletFiles) {
             Wallet childWallet = loadWallet(childFile, encryptionKey);
             Storage childStorage = new Storage(childFile);
             childStorage.setEncryptionPubKey(encryptionKey == null ? Storage.NO_PASSWORD_KEY : ECKey.fromPublicOnly(encryptionKey));
             childStorage.setKeyDeriver(getKeyDeriver());
             childWallet.setMasterWallet(masterWallet);
-            childWallets.put(childStorage, new WalletBackupAndKey(childWallet, null, encryptionKey, keyDeriver, Collections.emptyMap()));
+            childWallets.put(new WalletBackupAndKey(childWallet, null, encryptionKey, keyDeriver, Collections.emptyMap()), storage);
         }
 
         return childWallets;
@@ -200,6 +200,11 @@ public class JsonPersistence implements Persistence {
         return "BIE1".getBytes(StandardCharsets.UTF_8);
     }
 
+    @Override
+    public boolean isPersisted(Storage storage, Wallet wallet) {
+        return storage.getWalletFile().exists();
+    }
+
     @Override
     public ECKey getEncryptionKey(CharSequence password) throws IOException, StorageException {
         return getEncryptionKey(password, null, null);

src/main/java/com/sparrowwallet/sparrow/io/Persistence.java

@@ -16,6 +16,7 @@ public interface Persistence {
     File storeWallet(Storage storage, Wallet wallet, ECKey encryptionPubKey) throws IOException, StorageException;
     void updateWallet(Storage storage, Wallet wallet) throws IOException, StorageException;
     void updateWallet(Storage storage, Wallet wallet, ECKey encryptionPubKey) throws IOException, StorageException;
+    boolean isPersisted(Storage storage, Wallet wallet);
     ECKey getEncryptionKey(CharSequence password) throws IOException, StorageException;
     AsymmetricKeyDeriver getKeyDeriver();
     void setKeyDeriver(AsymmetricKeyDeriver keyDeriver);

src/main/java/com/sparrowwallet/sparrow/io/Sparrow.java

@@ -111,8 +111,8 @@ public class Sparrow implements WalletImport, WalletExport {
                 WalletBackupAndKey walletBackupAndKey = storage.loadEncryptedWallet(password);
                 wallet = walletBackupAndKey.getWallet();
                 wallet.decrypt(walletBackupAndKey.getKey());
-                for(Map.Entry<Storage, WalletBackupAndKey> entry : walletBackupAndKey.getChildWallets().entrySet()) {
-                    entry.getValue().getWallet().decrypt(entry.getValue().getKey());
+                for(Map.Entry<WalletBackupAndKey, Storage> entry : walletBackupAndKey.getChildWallets().entrySet()) {
+                    entry.getKey().getWallet().decrypt(entry.getKey().getKey());
                 }
             }
 

src/main/java/com/sparrowwallet/sparrow/io/Storage.java

@@ -115,6 +115,10 @@ public class Storage {
         }
     }
 
+    public boolean isPersisted(Wallet wallet) {
+        return persistence.isPersisted(this, wallet);
+    }
+
     public void close() {
         ClosePersistenceService closePersistenceService = new ClosePersistenceService();
         closePersistenceService.start();

src/main/java/com/sparrowwallet/sparrow/io/WalletBackupAndKey.java

@@ -5,14 +5,14 @@ import com.sparrowwallet.drongo.wallet.Wallet;
 
 import java.util.Map;
 
-public class WalletBackupAndKey {
+public class WalletBackupAndKey implements Comparable<WalletBackupAndKey> {
     private final Wallet wallet;
     private final Wallet backupWallet;
     private final ECKey encryptionKey;
     private final Key key;
-    private final Map<Storage, WalletBackupAndKey> childWallets;
+    private final Map<WalletBackupAndKey, Storage> childWallets;
 
-    public WalletBackupAndKey(Wallet wallet, Wallet backupWallet, ECKey encryptionKey, AsymmetricKeyDeriver keyDeriver, Map<Storage, WalletBackupAndKey> childWallets) {
+    public WalletBackupAndKey(Wallet wallet, Wallet backupWallet, ECKey encryptionKey, AsymmetricKeyDeriver keyDeriver, Map<WalletBackupAndKey, Storage> childWallets) {
         this.wallet = wallet;
         this.backupWallet = backupWallet;
         this.encryptionKey = encryptionKey;
@@ -36,7 +36,7 @@ public class WalletBackupAndKey {
         return key;
     }
 
-    public Map<Storage, WalletBackupAndKey> getChildWallets() {
+    public Map<WalletBackupAndKey, Storage> getChildWallets() {
         return childWallets;
     }
 
@@ -48,4 +48,13 @@ public class WalletBackupAndKey {
             key.clear();
         }
     }
+
+    @Override
+    public int compareTo(WalletBackupAndKey other) {
+        if(wallet.getStandardAccountType() != null && other.wallet.getStandardAccountType() != null) {
+            return wallet.getStandardAccountType().ordinal() - other.wallet.getStandardAccountType().ordinal();
+        }
+
+        return wallet.getAccountIndex() - other.wallet.getAccountIndex();
+    }
 }

src/main/java/com/sparrowwallet/sparrow/io/db/DbPersistence.java

@@ -90,20 +90,20 @@ public class DbPersistence implements Persistence {
             backupWallet = backupPersistence.loadWallet(new Storage(backupPersistence, backupFile), password, encryptionKey).getWallet();
         }
 
-        Map<Storage, WalletBackupAndKey> childWallets = loadChildWallets(storage, masterWallet, backupWallet, encryptionKey);
-        masterWallet.setChildWallets(childWallets.values().stream().map(WalletBackupAndKey::getWallet).collect(Collectors.toList()));
+        Map<WalletBackupAndKey, Storage> childWallets = loadChildWallets(storage, masterWallet, backupWallet, encryptionKey);
+        masterWallet.setChildWallets(childWallets.keySet().stream().map(WalletBackupAndKey::getWallet).collect(Collectors.toList()));
 
         return new WalletBackupAndKey(masterWallet, backupWallet, encryptionKey, keyDeriver, childWallets);
     }
 
-    private Map<Storage, WalletBackupAndKey> loadChildWallets(Storage storage, Wallet masterWallet, Wallet backupWallet, ECKey encryptionKey) throws StorageException {
+    private Map<WalletBackupAndKey, Storage> loadChildWallets(Storage storage, Wallet masterWallet, Wallet backupWallet, ECKey encryptionKey) throws StorageException {
         Jdbi jdbi = getJdbi(storage, getFilePassword(encryptionKey));
         List<String> schemas = jdbi.withHandle(handle -> {
            return handle.createQuery("show schemas").mapTo(String.class).list();
         });
 
         List<String> childSchemas = schemas.stream().filter(schema -> schema.startsWith(WALLET_SCHEMA_PREFIX) && !schema.equals(MASTER_SCHEMA)).collect(Collectors.toList());
-        Map<Storage, WalletBackupAndKey> childWallets = new LinkedHashMap<>();
+        Map<WalletBackupAndKey, Storage> childWallets = new TreeMap<>();
         for(String schema : childSchemas) {
             migrate(storage, schema, encryptionKey);
 
@@ -116,7 +116,7 @@ public class DbPersistence implements Persistence {
                 return childWallet;
             });
             Wallet backupChildWallet = backupWallet == null ? null : backupWallet.getChildWallets().stream().filter(child -> wallet.getName().equals(child.getName())).findFirst().orElse(null);
-            childWallets.put(storage, new WalletBackupAndKey(wallet, backupChildWallet, encryptionKey, keyDeriver, Collections.emptyMap()));
+            childWallets.put(new WalletBackupAndKey(wallet, backupChildWallet, encryptionKey, keyDeriver, Collections.emptyMap()), storage);
         }
 
         return childWallets;
@@ -184,6 +184,14 @@ public class DbPersistence implements Persistence {
         log.debug(dirtyPersistables.toString());
 
         Jdbi jdbi = getJdbi(storage, password);
+        List<String> schemas = jdbi.withHandle(handle -> {
+            return handle.createQuery("show schemas").mapTo(String.class).list();
+        });
+        if(!schemas.contains(getSchema(wallet))) {
+            log.debug("Not persisting update for missing schema " + getSchema(wallet));
+            return;
+        }
+
         jdbi.useHandle(handle -> {
             WalletDao walletDao = handle.attach(WalletDao.class);
             try {
@@ -399,6 +407,11 @@ public class DbPersistence implements Persistence {
         return null;
     }
 
+    @Override
+    public boolean isPersisted(Storage storage, Wallet wallet) {
+        return wallet.getId() != null;
+    }
+
     @Override
     public ECKey getEncryptionKey(CharSequence password) throws IOException {
         return getEncryptionKey(password, null, null);

src/main/java/com/sparrowwallet/sparrow/net/ElectrumServer.java

@@ -100,8 +100,9 @@ public class ElectrumServer {
                 previousServerAddress = electrumServer;
 
                 HostAndPort server = protocol.getServerHostAndPort(electrumServer);
+                boolean localNetworkAddress = !protocol.isOnionAddress(server) && IpAddressMatcher.isLocalNetworkAddress(server.getHost());
 
-                if(Config.get().isUseProxy() && proxyServer != null && !proxyServer.isBlank()) {
+                if(!localNetworkAddress && Config.get().isUseProxy() && proxyServer != null && !proxyServer.isBlank()) {
                     HostAndPort proxy = HostAndPort.fromString(proxyServer);
                     if(electrumServerCert != null) {
                         transport = protocol.getTransport(server, electrumServerCert, proxy);
@@ -765,6 +766,31 @@ public class ElectrumServer {
         return Transaction.DEFAULT_MIN_RELAY_FEE;
     }
 
+    public Sha256Hash broadcastTransactionPrivately(Transaction transaction) throws ServerException {
+        //If Tor proxy is configured, try all external broadcast sources in random order before falling back to connected Electrum server
+        if(AppServices.isUsingProxy()) {
+            List<BroadcastSource> broadcastSources = Arrays.stream(BroadcastSource.values()).filter(src -> src.getSupportedNetworks().contains(Network.get())).collect(Collectors.toList());
+            Sha256Hash txid = null;
+            for(int i = 1; !broadcastSources.isEmpty(); i++) {
+                try {
+                    BroadcastSource broadcastSource = broadcastSources.remove(new Random().nextInt(broadcastSources.size()));
+                    txid = broadcastSource.broadcastTransaction(transaction);
+                    if(Network.get() != Network.MAINNET || i >= MINIMUM_BROADCASTS || broadcastSources.isEmpty()) {
+                        return txid;
+                    }
+                } catch(BroadcastSource.BroadcastException e) {
+                    //ignore, already logged
+                }
+            }
+
+            if(txid != null) {
+                return txid;
+            }
+        }
+
+        return broadcastTransaction(transaction);
+    }
+
     public Sha256Hash broadcastTransaction(Transaction transaction) throws ServerException {
         byte[] rawtxBytes = transaction.bitcoinSerialize();
         String rawtxHex = Utils.bytesToHex(rawtxBytes);
@@ -1351,29 +1377,8 @@ public class ElectrumServer {
         protected Task<Sha256Hash> createTask() {
             return new Task<>() {
                 protected Sha256Hash call() throws ServerException {
-                    //If Tor proxy is configured, try all external broadcast sources in random order before falling back to connected Electrum server
-                    if(AppServices.isUsingProxy()) {
-                        List<BroadcastSource> broadcastSources = Arrays.stream(BroadcastSource.values()).filter(src -> src.getSupportedNetworks().contains(Network.get())).collect(Collectors.toList());
-                        Sha256Hash txid = null;
-                        for(int i = 1; !broadcastSources.isEmpty(); i++) {
-                            try {
-                                BroadcastSource broadcastSource = broadcastSources.remove(new Random().nextInt(broadcastSources.size()));
-                                txid = broadcastSource.broadcastTransaction(transaction);
-                                if(Network.get() != Network.MAINNET || i >= MINIMUM_BROADCASTS || broadcastSources.isEmpty()) {
-                                    return txid;
-                                }
-                            } catch(BroadcastSource.BroadcastException e) {
-                                //ignore, already logged
-                            }
-                        }
-
-                        if(txid != null) {
-                            return txid;
-                        }
-                    }
-
                     ElectrumServer electrumServer = new ElectrumServer();
-                    return electrumServer.broadcastTransaction(transaction);
+                    return electrumServer.broadcastTransactionPrivately(transaction);
                 }
             };
         }

src/main/java/com/sparrowwallet/sparrow/net/IpAddressMatcher.java

@@ -0,0 +1,109 @@
+package com.sparrowwallet.sparrow.net;
+
+/*
+ * Copyright 2002-2019 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import java.net.InetAddress;
+import java.net.UnknownHostException;
+
+/**
+ * Matches a request based on IP Address or subnet mask matching against the remote
+ * address.
+ * <p>
+ * Both IPv6 and IPv4 addresses are supported, but a matcher which is configured with an
+ * IPv4 address will never match a request which returns an IPv6 address, and vice-versa.
+ *
+ * @author Luke Taylor
+ * @since 3.0.2
+ *
+ * Slightly modified by omidzk to have zero dependency to any frameworks other than the JRE.
+ */
+public final class IpAddressMatcher {
+    private static final IpAddressMatcher LOCAL_RANGE_1 = new IpAddressMatcher("10.0.0.0/8");
+    private static final IpAddressMatcher LOCAL_RANGE_2 = new IpAddressMatcher("172.16.0.0/12");
+    private static final IpAddressMatcher LOCAL_RANGE_3 = new IpAddressMatcher("192.168.0.0/16");
+
+    private final int nMaskBits;
+    private final InetAddress requiredAddress;
+
+    /**
+     * Takes a specific IP address or a range specified using the IP/Netmask (e.g.
+     * 192.168.1.0/24 or 202.24.0.0/14).
+     *
+     * @param ipAddress the address or range of addresses from which the request must
+     * come.
+     */
+    public IpAddressMatcher(String ipAddress) {
+
+        if (ipAddress.indexOf('/') > 0) {
+            String[] addressAndMask = ipAddress.split("/");
+            ipAddress = addressAndMask[0];
+            nMaskBits = Integer.parseInt(addressAndMask[1]);
+        }
+        else {
+            nMaskBits = -1;
+        }
+        requiredAddress = parseAddress(ipAddress);
+        assert  (requiredAddress.getAddress().length * 8 >= nMaskBits) :
+                String.format("IP address %s is too short for bitmask of length %d",
+                        ipAddress, nMaskBits);
+    }
+
+    public boolean matches(String address) {
+        InetAddress remoteAddress = parseAddress(address);
+
+        if (!requiredAddress.getClass().equals(remoteAddress.getClass())) {
+            return false;
+        }
+
+        if (nMaskBits < 0) {
+            return remoteAddress.equals(requiredAddress);
+        }
+
+        byte[] remAddr = remoteAddress.getAddress();
+        byte[] reqAddr = requiredAddress.getAddress();
+
+        int nMaskFullBytes = nMaskBits / 8;
+        byte finalByte = (byte) (0xFF00 >> (nMaskBits & 0x07));
+
+        // System.out.println("Mask is " + new sun.misc.HexDumpEncoder().encode(mask));
+
+        for (int i = 0; i < nMaskFullBytes; i++) {
+            if (remAddr[i] != reqAddr[i]) {
+                return false;
+            }
+        }
+
+        if (finalByte != 0) {
+            return (remAddr[nMaskFullBytes] & finalByte) == (reqAddr[nMaskFullBytes] & finalByte);
+        }
+
+        return true;
+    }
+
+    private InetAddress parseAddress(String address) {
+        try {
+            return InetAddress.getByName(address);
+        }
+        catch (UnknownHostException e) {
+            throw new IllegalArgumentException("Failed to parse address" + address, e);
+        }
+    }
+
+    public static boolean isLocalNetworkAddress(String address) {
+        return LOCAL_RANGE_1.matches(address) || LOCAL_RANGE_2.matches(address) || LOCAL_RANGE_3.matches(address);
+    }
+}

src/main/java/com/sparrowwallet/sparrow/wallet/PaymentController.java

@@ -72,6 +72,9 @@ public class PaymentController extends WalletFormController implements Initializ
     @FXML
     private ToggleButton maxButton;
 
+    @FXML
+    private Button scanQrButton;
+
     @FXML
     private Button addPaymentButton;
 
@@ -287,11 +290,16 @@ public class PaymentController extends WalletFormController implements Initializ
 
     public Payment getPayment(boolean sendAll) {
         try {
-            Address address = getRecipientAddress();
+            Address recipientAddress = getRecipientAddress();
             Long value = sendAll ? Long.valueOf(getRecipientDustThreshold() + 1) : getRecipientValueSats();
 
             if(!label.getText().isEmpty() && value != null && value > getRecipientDustThreshold()) {
-                return new Payment(address, label.getText(), value, sendAll);
+                Payment payment = new Payment(recipientAddress, label.getText(), value, sendAll);
+                if(address.getUserData() != null) {
+                    payment.setType((Payment.Type)address.getUserData());
+                }
+
+                return payment;
             }
         } catch(InvalidAddressException e) {
             //ignore
@@ -304,6 +312,7 @@ public class PaymentController extends WalletFormController implements Initializ
         if(getRecipientValueSats() == null || payment.getAmount() != getRecipientValueSats()) {
             if(payment.getAddress() != null) {
                 address.setText(payment.getAddress().toString());
+                address.setUserData(payment.getType());
             }
             if(payment.getLabel() != null && !label.getText().equals(payment.getLabel())) {
                 label.setText(payment.getLabel());
@@ -406,6 +415,16 @@ public class PaymentController extends WalletFormController implements Initializ
         maxButton.setSelected(sendMax);
     }
 
+    public void setInputFieldsDisabled(boolean disable) {
+        address.setDisable(disable);
+        label.setDisable(disable);
+        amount.setDisable(disable);
+        amountUnit.setDisable(disable);
+        maxButton.setDisable(disable);
+        scanQrButton.setDisable(disable);
+        addPaymentButton.setDisable(disable);
+    }
+
     @Subscribe
     public void bitcoinUnitChanged(BitcoinUnitChangedEvent event) {
         BitcoinUnit unit = sendController.getBitcoinUnit(event.getBitcoinUnit());

src/main/java/com/sparrowwallet/sparrow/wallet/SendController.java

@@ -1,8 +1,11 @@
 package com.sparrowwallet.sparrow.wallet;
 
 import com.google.common.eventbus.Subscribe;
+import com.samourai.whirlpool.client.whirlpool.beans.Pool;
 import com.sparrowwallet.drongo.BitcoinUnit;
+import com.sparrowwallet.drongo.SecureString;
 import com.sparrowwallet.drongo.address.InvalidAddressException;
+import com.sparrowwallet.drongo.protocol.Sha256Hash;
 import com.sparrowwallet.drongo.protocol.Transaction;
 import com.sparrowwallet.drongo.psbt.PSBT;
 import com.sparrowwallet.drongo.wallet.*;
@@ -13,7 +16,9 @@ import com.sparrowwallet.sparrow.control.*;
 import com.sparrowwallet.sparrow.event.*;
 import com.sparrowwallet.sparrow.glyphfont.FontAwesome5;
 import com.sparrowwallet.sparrow.io.Config;
+import com.sparrowwallet.sparrow.io.Storage;
 import com.sparrowwallet.sparrow.net.*;
+import com.sparrowwallet.sparrow.whirlpool.Whirlpool;
 import javafx.animation.KeyFrame;
 import javafx.animation.Timeline;
 import javafx.application.Platform;
@@ -116,6 +121,9 @@ public class SendController extends WalletFormController implements Initializabl
     @FXML
     private Button createButton;
 
+    @FXML
+    private Button premixButton;
+
     private StackPane tabHeader;
 
     private final BooleanProperty userFeeSet = new SimpleBooleanProperty(false);
@@ -124,6 +132,8 @@ public class SendController extends WalletFormController implements Initializabl
 
     private final ObjectProperty<UtxoFilter> utxoFilterProperty = new SimpleObjectProperty<>(null);
 
+    private final ObjectProperty<Pool> whirlpoolProperty = new SimpleObjectProperty<>(null);
+
     private final ObjectProperty<WalletTransaction> walletTransactionProperty = new SimpleObjectProperty<>(null);
 
     private final ObjectProperty<WalletTransaction> createdWalletTransactionProperty = new SimpleObjectProperty<>(null);
@@ -370,6 +380,14 @@ public class SendController extends WalletFormController implements Initializabl
         });
 
         addFeeRangeTrackHighlight(0);
+
+        createButton.managedProperty().bind(createButton.visibleProperty());
+        premixButton.managedProperty().bind(premixButton.visibleProperty());
+        createButton.visibleProperty().bind(premixButton.visibleProperty().not());
+        premixButton.setVisible(false);
+        AppServices.onlineProperty().addListener((observable, oldValue, newValue) -> {
+            premixButton.setDisable(!newValue);
+        });
     }
 
     private void initializeTabHeader(int count) {
@@ -379,7 +397,7 @@ public class SendController extends WalletFormController implements Initializabl
             if(stackPane != null) {
                 tabHeader = stackPane;
                 tabHeader.managedProperty().bind(tabHeader.visibleProperty());
-                tabHeader.setVisible(false);
+                tabHeader.setVisible(paymentTabs.getTabs().size() > 1);
                 paymentTabs.getStyleClass().remove("initial");
             } else if(lookupCount < 20) {
                 initializeTabHeader(lookupCount+1);
@@ -908,6 +926,8 @@ public class SendController extends WalletFormController implements Initializabl
         insufficientInputsProperty.set(false);
 
         validationSupport.setErrorDecorationEnabled(false);
+
+        setInputFieldsDisabled(false);
     }
 
     public UtxoSelector getUtxoSelector() {
@@ -993,6 +1013,88 @@ public class SendController extends WalletFormController implements Initializabl
         walletForm.addWalletTransactionNodes(nodes);
     }
 
+    public void broadcastPremix(ActionEvent event) {
+        //Ensure all child wallets have been saved
+        for(Wallet childWallet : getWalletForm().getWallet().getChildWallets()) {
+            Storage storage = AppServices.get().getOpenWallets().get(childWallet);
+            if(!storage.isPersisted(childWallet)) {
+                try {
+                    storage.saveWallet(childWallet);
+                } catch(Exception e) {
+                    AppServices.showErrorDialog("Error saving wallet " + childWallet.getName(), e.getMessage());
+                }
+            }
+        }
+
+        Wallet copy = getWalletForm().getWallet().copy();
+        String walletId = walletForm.getWalletId();
+
+        if(copy.isEncrypted()) {
+            WalletPasswordDialog dlg = new WalletPasswordDialog(copy.getMasterName(), WalletPasswordDialog.PasswordRequirement.LOAD);
+            Optional<SecureString> password = dlg.showAndWait();
+            if(password.isPresent()) {
+                Storage.DecryptWalletService decryptWalletService = new Storage.DecryptWalletService(copy, password.get());
+                decryptWalletService.setOnSucceeded(workerStateEvent -> {
+                    EventManager.get().post(new StorageEvent(walletId, TimedEvent.Action.END, "Done"));
+                    Wallet decryptedWallet = decryptWalletService.getValue();
+                    broadcastPremixUnencrypted(decryptedWallet);
+                });
+                decryptWalletService.setOnFailed(workerStateEvent -> {
+                    EventManager.get().post(new StorageEvent(walletId, TimedEvent.Action.END, "Failed"));
+                    AppServices.showErrorDialog("Incorrect Password", decryptWalletService.getException().getMessage());
+                });
+                EventManager.get().post(new StorageEvent(walletId, TimedEvent.Action.START, "Decrypting wallet..."));
+                decryptWalletService.start();
+            }
+        } else {
+            broadcastPremixUnencrypted(copy);
+        }
+    }
+
+    public void broadcastPremixUnencrypted(Wallet decryptedWallet) {
+        Whirlpool whirlpool = AppServices.get().getWhirlpool(getWalletForm().getWalletId());
+        whirlpool.setScode(Config.get().getScode());
+        whirlpool.setHDWallet(decryptedWallet);
+        Map<BlockTransactionHashIndex, WalletNode> utxos = walletTransactionProperty.get().getSelectedUtxos();
+        Whirlpool.Tx0BroadcastService tx0BroadcastService = new Whirlpool.Tx0BroadcastService(whirlpool, whirlpoolProperty.get(), utxos.keySet());
+        tx0BroadcastService.setOnRunning(workerStateEvent -> {
+            premixButton.setDisable(true);
+            addWalletTransactionNodes();
+        });
+        tx0BroadcastService.setOnSucceeded(workerStateEvent -> {
+            premixButton.setDisable(false);
+            Sha256Hash txid = tx0BroadcastService.getValue();
+            decryptedWallet.clearPrivate();
+            clear(null);
+        });
+        tx0BroadcastService.setOnFailed(workerStateEvent -> {
+            premixButton.setDisable(false);
+            decryptedWallet.clearPrivate();
+            Throwable exception = workerStateEvent.getSource().getException();
+            while(exception.getCause() != null) {
+                exception = exception.getCause();
+            }
+
+            AppServices.showErrorDialog("Error broadcasting premix transaction", exception.getMessage());
+        });
+        ServiceProgressDialog progressDialog = new ServiceProgressDialog("Whirlpool", "Broadcast Premix Transaction", "/image/whirlpool.png", tx0BroadcastService);
+        tx0BroadcastService.start();
+    }
+
+    private void setInputFieldsDisabled(boolean disable) {
+        for(int i = 0; i < paymentTabs.getTabs().size(); i++) {
+            Tab tab = paymentTabs.getTabs().get(i);
+            tab.setClosable(!disable);
+            PaymentController controller = (PaymentController)tab.getUserData();
+            controller.setInputFieldsDisabled(disable);
+
+            feeRange.setDisable(disable);
+            targetBlocks.setDisable(disable);
+            fee.setDisable(disable);
+            feeAmountUnit.setDisable(disable);
+        }
+    }
+
     @Subscribe
     public void walletNodesChanged(WalletNodesChangedEvent event) {
         if(event.getWallet().equals(walletForm.getWallet())) {
@@ -1079,7 +1181,13 @@ public class SendController extends WalletFormController implements Initializabl
             List<BlockTransactionHashIndex> utxos = event.getUtxos();
             utxoSelectorProperty.set(new PresetUtxoSelector(utxos));
             utxoFilterProperty.set(null);
+            whirlpoolProperty.set(event.getPool());
             updateTransaction(event.getPayments() == null || event.getPayments().stream().anyMatch(Payment::isSendMax));
+
+            boolean isWhirlpoolPremix = (event.getPayments() != null && event.getPayments().stream().anyMatch(payment -> payment.getType().equals(Payment.Type.WHIRLPOOL_FEE)));
+            setInputFieldsDisabled(isWhirlpoolPremix);
+            premixButton.setVisible(isWhirlpoolPremix);
+            premixButton.setDefaultButton(isWhirlpoolPremix);
         }
     }
 

src/main/java/com/sparrowwallet/sparrow/wallet/UtxosController.java

@@ -2,17 +2,20 @@ package com.sparrowwallet.sparrow.wallet;
 
 import com.csvreader.CsvWriter;
 import com.google.common.eventbus.Subscribe;
+import com.samourai.whirlpool.client.tx0.Tx0Preview;
 import com.sparrowwallet.drongo.BitcoinUnit;
+import com.sparrowwallet.drongo.KeyPurpose;
+import com.sparrowwallet.drongo.Network;
+import com.sparrowwallet.drongo.address.Address;
+import com.sparrowwallet.drongo.address.InvalidAddressException;
 import com.sparrowwallet.drongo.protocol.Transaction;
-import com.sparrowwallet.drongo.wallet.BlockTransactionHashIndex;
+import com.sparrowwallet.drongo.wallet.*;
 import com.sparrowwallet.sparrow.AppServices;
 import com.sparrowwallet.sparrow.EventManager;
-import com.sparrowwallet.sparrow.control.CoinLabel;
-import com.sparrowwallet.sparrow.control.EntryCell;
-import com.sparrowwallet.sparrow.control.UtxosChart;
-import com.sparrowwallet.sparrow.control.UtxosTreeTable;
+import com.sparrowwallet.sparrow.control.*;
 import com.sparrowwallet.sparrow.event.*;
 import com.sparrowwallet.sparrow.io.Config;
+import com.sparrowwallet.sparrow.whirlpool.WhirlpoolDialog;
 import javafx.application.Platform;
 import javafx.collections.ListChangeListener;
 import javafx.event.ActionEvent;
@@ -30,9 +33,7 @@ import java.io.FileOutputStream;
 import java.io.IOException;
 import java.net.URL;
 import java.nio.charset.StandardCharsets;
-import java.util.List;
-import java.util.Locale;
-import java.util.ResourceBundle;
+import java.util.*;
 import java.util.stream.Collectors;
 
 public class UtxosController extends WalletFormController implements Initializable {
@@ -44,6 +45,9 @@ public class UtxosController extends WalletFormController implements Initializab
     @FXML
     private Button sendSelected;
 
+    @FXML
+    private Button mixSelected;
+
     @FXML
     private UtxosChart utxosChart;
 
@@ -58,23 +62,33 @@ public class UtxosController extends WalletFormController implements Initializab
         utxosChart.initialize(getWalletForm().getWalletUtxosEntry());
         sendSelected.setDisable(true);
         sendSelected.setTooltip(new Tooltip("Send selected UTXOs. Use " + (org.controlsfx.tools.Platform.getCurrent() == org.controlsfx.tools.Platform.OSX ? "Cmd" : "Ctrl") + "+click to select multiple." ));
+        mixSelected.managedProperty().bind(mixSelected.visibleProperty());
+        mixSelected.setVisible(canWalletMix());
+        mixSelected.setDisable(true);
+        AppServices.onlineProperty().addListener((observable, oldValue, newValue) -> {
+            mixSelected.setDisable(getSelectedEntries().isEmpty() || !newValue);
+        });
 
         utxosTable.getSelectionModel().getSelectedIndices().addListener((ListChangeListener<Integer>) c -> {
             List<Entry> selectedEntries = utxosTable.getSelectionModel().getSelectedCells().stream().map(tp -> tp.getTreeItem().getValue()).collect(Collectors.toList());
             utxosChart.select(selectedEntries);
-            updateSendSelected(Config.get().getBitcoinUnit());
+            updateButtons(Config.get().getBitcoinUnit());
         });
 
         utxosChart.managedProperty().bind(utxosChart.visibleProperty());
         utxosChart.setVisible(Config.get().isShowUtxosChart());
     }
 
-    private void updateSendSelected(BitcoinUnit unit) {
-        List<Entry> selectedEntries = utxosTable.getSelectionModel().getSelectedCells().stream().map(tp -> tp.getTreeItem().getValue())
-                .filter(entry -> ((HashIndexEntry)entry).isSpendable())
-                .collect(Collectors.toList());
+    private boolean canWalletMix() {
+        return Network.get() == Network.TESTNET && getWalletForm().getWallet().getKeystores().size() == 1 && getWalletForm().getWallet().getKeystores().get(0).hasSeed();
+    }
+
+    private void updateButtons(BitcoinUnit unit) {
+        List<Entry> selectedEntries = getSelectedEntries();
 
         sendSelected.setDisable(selectedEntries.isEmpty());
+        mixSelected.setDisable(selectedEntries.isEmpty() || !AppServices.isConnected());
+
         long selectedTotal = selectedEntries.stream().mapToLong(Entry::getValue).sum();
         if(selectedTotal > 0) {
             if(unit == null || unit.equals(BitcoinUnit.AUTO)) {
@@ -83,27 +97,85 @@ public class UtxosController extends WalletFormController implements Initializab
 
             if(unit.equals(BitcoinUnit.BTC)) {
                 sendSelected.setText("Send Selected (" + CoinLabel.getBTCFormat().format((double)selectedTotal / Transaction.SATOSHIS_PER_BITCOIN) + " BTC)");
+                mixSelected.setText("Mix Selected (" + CoinLabel.getBTCFormat().format((double)selectedTotal / Transaction.SATOSHIS_PER_BITCOIN) + " BTC)");
             } else {
                 sendSelected.setText("Send Selected (" + String.format(Locale.ENGLISH, "%,d", selectedTotal) + " sats)");
+                mixSelected.setText("Mix Selected (" + String.format(Locale.ENGLISH, "%,d", selectedTotal) + " sats)");
             }
         } else {
             sendSelected.setText("Send Selected");
+            sendSelected.setText("Mix Selected");
         }
     }
 
-    public void sendSelected(ActionEvent event) {
-        List<HashIndexEntry> utxoEntries = utxosTable.getSelectionModel().getSelectedCells().stream()
-                .map(tp -> tp.getTreeItem().getValue())
-                .filter(e -> e instanceof HashIndexEntry)
-                .map(e -> (HashIndexEntry)e)
-                .filter(e -> e.getType().equals(HashIndexEntry.Type.OUTPUT) && e.isSpendable())
+    private List<Entry> getSelectedEntries() {
+        return utxosTable.getSelectionModel().getSelectedCells().stream().map(tp -> tp.getTreeItem().getValue())
+                .filter(entry -> ((HashIndexEntry)entry).isSpendable())
                 .collect(Collectors.toList());
+    }
 
+    public void sendSelected(ActionEvent event) {
+        List<UtxoEntry> utxoEntries = getSelectedUtxos();
         final List<BlockTransactionHashIndex> spendingUtxos = utxoEntries.stream().map(HashIndexEntry::getHashIndex).collect(Collectors.toList());
         EventManager.get().post(new SendActionEvent(getWalletForm().getWallet(), spendingUtxos));
         Platform.runLater(() -> EventManager.get().post(new SpendUtxoEvent(getWalletForm().getWallet(), spendingUtxos)));
     }
 
+    public void mixSelected(ActionEvent event) {
+        List<UtxoEntry> selectedEntries = getSelectedUtxos();
+        WhirlpoolDialog whirlpoolDialog = new WhirlpoolDialog(getWalletForm().getWalletId(), getWalletForm().getWallet(), selectedEntries);
+        Optional<Tx0Preview> optTx0Preview = whirlpoolDialog.showAndWait();
+        optTx0Preview.ifPresent(tx0Preview -> previewPremixTransaction(getWalletForm().getWallet(), tx0Preview, selectedEntries));
+    }
+
+    public void previewPremixTransaction(Wallet wallet, Tx0Preview tx0Preview, List<UtxoEntry> utxoEntries) {
+        for(StandardAccount whirlpoolAccount : StandardAccount.WHIRLPOOL_ACCOUNTS) {
+            if(wallet.getChildWallet(whirlpoolAccount) == null) {
+                Wallet childWallet = wallet.addChildWallet(whirlpoolAccount);
+                EventManager.get().post(new ChildWalletAddedEvent(getWalletForm().getStorage(), wallet, childWallet));
+            }
+        }
+
+        Wallet premixWallet = wallet.getChildWallet(StandardAccount.WHIRLPOOL_PREMIX);
+        Wallet badbankWallet = wallet.getChildWallet(StandardAccount.WHIRLPOOL_BADBANK);
+
+        List<Payment> payments = new ArrayList<>();
+        try {
+            Address whirlpoolFeeAddress = Address.fromString(tx0Preview.getTx0Data().getFeeAddress());
+            Payment whirlpoolFeePayment = new Payment(whirlpoolFeeAddress, "Whirlpool Fee", tx0Preview.getFeeValue(), false);
+            whirlpoolFeePayment.setType(Payment.Type.WHIRLPOOL_FEE);
+            payments.add(whirlpoolFeePayment);
+        } catch(InvalidAddressException e) {
+            throw new IllegalStateException("Cannot parse whirlpool fee address " + tx0Preview.getTx0Data().getFeeAddress(), e);
+        }
+
+        WalletNode badbankNode = badbankWallet.getFreshNode(KeyPurpose.RECEIVE);
+        Payment changePayment = new Payment(badbankWallet.getAddress(badbankNode), "Badbank Change", tx0Preview.getChangeValue(), false);
+        payments.add(changePayment);
+
+        WalletNode premixNode = null;
+        for(int i = 0; i < tx0Preview.getNbPremix(); i++) {
+            premixNode = premixWallet.getFreshNode(KeyPurpose.RECEIVE, premixNode);
+            Address premixAddress = premixWallet.getAddress(premixNode);
+            payments.add(new Payment(premixAddress, "Premix #" + i, tx0Preview.getPremixValue(), false));
+        }
+
+        final List<BlockTransactionHashIndex> utxos = utxoEntries.stream().map(HashIndexEntry::getHashIndex).collect(Collectors.toList());
+        Platform.runLater(() -> {
+            EventManager.get().post(new SendActionEvent(getWalletForm().getWallet(), utxos));
+            Platform.runLater(() -> EventManager.get().post(new SpendUtxoEvent(getWalletForm().getWallet(), utxos, payments, tx0Preview.getTx0MinerFee(), tx0Preview.getPool())));
+        });
+    }
+
+    private List<UtxoEntry> getSelectedUtxos() {
+        return utxosTable.getSelectionModel().getSelectedCells().stream()
+                .map(tp -> tp.getTreeItem().getValue())
+                .filter(e -> e instanceof HashIndexEntry)
+                .map(e -> (UtxoEntry)e)
+                .filter(e -> e.getType().equals(HashIndexEntry.Type.OUTPUT) && e.isSpendable())
+                .collect(Collectors.toList());
+    }
+
     public void clear(ActionEvent event) {
         utxosTable.getSelectionModel().clearSelection();
     }
@@ -150,6 +222,7 @@ public class UtxosController extends WalletFormController implements Initializab
             WalletUtxosEntry walletUtxosEntry = getWalletForm().getWalletUtxosEntry();
             utxosTable.updateAll(walletUtxosEntry);
             utxosChart.update(walletUtxosEntry);
+            mixSelected.setVisible(canWalletMix());
         }
     }
 
@@ -180,7 +253,7 @@ public class UtxosController extends WalletFormController implements Initializab
     public void bitcoinUnitChanged(BitcoinUnitChangedEvent event) {
         utxosTable.setBitcoinUnit(getWalletForm().getWallet(), event.getBitcoinUnit());
         utxosChart.setBitcoinUnit(getWalletForm().getWallet(), event.getBitcoinUnit());
-        updateSendSelected(event.getBitcoinUnit());
+        updateButtons(event.getBitcoinUnit());
     }
 
     @Subscribe
@@ -213,7 +286,7 @@ public class UtxosController extends WalletFormController implements Initializab
     public void walletUtxoStatusChanged(WalletUtxoStatusChangedEvent event) {
         if(event.getWallet().equals(getWalletForm().getWallet())) {
             utxosTable.refresh();
-            updateSendSelected(Config.get().getBitcoinUnit());
+            updateButtons(Config.get().getBitcoinUnit());
         }
     }
 

src/main/java/com/sparrowwallet/sparrow/whirlpool/SparrowBackendApi.java

@@ -0,0 +1,277 @@
+package com.sparrowwallet.sparrow.whirlpool;
+
+import com.samourai.wallet.api.backend.BackendApi;
+import com.samourai.wallet.api.backend.MinerFee;
+import com.samourai.wallet.api.backend.MinerFeeTarget;
+import com.samourai.wallet.api.backend.beans.*;
+import com.sparrowwallet.drongo.ExtendedKey;
+import com.sparrowwallet.drongo.KeyPurpose;
+import com.sparrowwallet.drongo.Network;
+import com.sparrowwallet.drongo.Utils;
+import com.sparrowwallet.drongo.address.Address;
+import com.sparrowwallet.drongo.protocol.*;
+import com.sparrowwallet.drongo.wallet.BlockTransaction;
+import com.sparrowwallet.drongo.wallet.BlockTransactionHashIndex;
+import com.sparrowwallet.drongo.wallet.Wallet;
+import com.sparrowwallet.drongo.wallet.WalletNode;
+import com.sparrowwallet.sparrow.AppServices;
+import com.sparrowwallet.sparrow.net.ElectrumServer;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.*;
+
+@SuppressWarnings("deprecation")
+public class SparrowBackendApi extends BackendApi {
+    private static final Logger log = LoggerFactory.getLogger(SparrowBackendApi.class);
+    private static final int FALLBACK_FEE_RATE = 75;
+
+    public SparrowBackendApi() {
+        super(null, null);
+    }
+
+    @Override
+    public TxsResponse fetchTxs(String[] zpubs, int page, int count) throws Exception {
+        List<TxsResponse.Tx> txes = new ArrayList<>();
+
+        for(String zpub : zpubs) {
+            Wallet wallet = getWallet(zpub);
+            if(wallet == null) {
+                log.debug("No wallet for " + zpub + " found");
+                continue;
+            }
+
+            for(BlockTransaction blockTransaction : wallet.getTransactions().values()) {
+                TxsResponse.Tx tx = new TxsResponse.Tx();
+                tx.block_height = blockTransaction.getHeight();
+                tx.hash = blockTransaction.getHashAsString();
+                tx.locktime = blockTransaction.getTransaction().getLocktime();
+                tx.time = blockTransaction.getDate().getTime();
+                tx.version = (int)blockTransaction.getTransaction().getVersion();
+
+                tx.inputs = new TxsResponse.TxInput[blockTransaction.getTransaction().getInputs().size()];
+                for(int i = 0; i < blockTransaction.getTransaction().getInputs().size(); i++) {
+                    TransactionInput txInput = blockTransaction.getTransaction().getInputs().get(i);
+                    tx.inputs[i] = new TxsResponse.TxInput();
+                    tx.inputs[i].vin = txInput.getIndex();
+                    tx.inputs[i].sequence = txInput.getSequenceNumber();
+                    tx.inputs[i].prev_out = new TxsResponse.TxOut();
+                    tx.inputs[i].prev_out.txid = txInput.getOutpoint().getHash().toString();
+                    tx.inputs[i].prev_out.vout = (int)txInput.getOutpoint().getIndex();
+
+                    BlockTransaction spentTransaction = wallet.getTransactions().get(txInput.getOutpoint().getHash());
+                    if(spentTransaction != null) {
+                        TransactionOutput spentOutput = spentTransaction.getTransaction().getOutputs().get((int)txInput.getOutpoint().getIndex());
+                        tx.inputs[i].prev_out.value = spentOutput.getValue();
+                        Address[] addresses = spentOutput.getScript().getToAddresses();
+                        if(addresses.length > 0) {
+                            tx.inputs[i].prev_out.addr = addresses[0].toString();
+                        }
+                    }
+                }
+
+                tx.out = new TxsResponse.TxOutput[blockTransaction.getTransaction().getOutputs().size()];
+                for(int i = 0; i < blockTransaction.getTransaction().getOutputs().size(); i++) {
+                    TransactionOutput txOutput = blockTransaction.getTransaction().getOutputs().get(i);
+                    tx.out[i].n = txOutput.getIndex();
+                    tx.out[i].value = txOutput.getValue();
+                    Address[] addresses = txOutput.getScript().getToAddresses();
+                    if(addresses.length > 0) {
+                        tx.out[i].addr = addresses[0].toString();
+                    }
+                }
+
+                txes.add(tx);
+            }
+        }
+
+        List<TxsResponse.Tx> pageTxes;
+        if(txes.size() < count) {
+            pageTxes = txes;
+        } else {
+            pageTxes = txes.subList(page * count, Math.min((page * count) + count, txes.size()));
+        }
+
+        TxsResponse txsResponse = new TxsResponse();
+        txsResponse.n_tx = txes.size();
+        txsResponse.page = page;
+        txsResponse.n_tx_page = pageTxes.size();
+        txsResponse.txs = pageTxes.toArray(new TxsResponse.Tx[0]);
+
+        return txsResponse;
+    }
+
+    @Override
+    public WalletResponse fetchWallet(String[] zpubs) throws Exception {
+        WalletResponse walletResponse = new WalletResponse();
+        walletResponse.wallet = new WalletResponse.Wallet();
+
+        Map<Sha256Hash, BlockTransaction> allTransactions = new HashMap<>();
+        Map<Sha256Hash, String> allTransactionsZpubs = new HashMap<>();
+        List<WalletResponse.Address> addresses = new ArrayList<>();
+        List<WalletResponse.Tx> txes = new ArrayList<>();
+        List<UnspentOutput> unspentOutputs = new ArrayList<>();
+        int storedBlockHeight = 0;
+
+        for(String zpub : zpubs) {
+            Wallet wallet = getWallet(zpub);
+            if(wallet == null) {
+                log.debug("No wallet for " + zpub + " found");
+                continue;
+            }
+
+            allTransactions.putAll(wallet.getTransactions());
+            wallet.getTransactions().keySet().forEach(txid -> allTransactionsZpubs.put(txid, zpub));
+            if(wallet.getStoredBlockHeight() != null) {
+                storedBlockHeight = Math.max(storedBlockHeight, wallet.getStoredBlockHeight());
+            }
+
+            WalletResponse.Address address = new WalletResponse.Address();
+            List<ExtendedKey.Header> headers = ExtendedKey.Header.getHeaders(Network.get());
+            ExtendedKey.Header header = headers.stream().filter(head -> head.getDefaultScriptType().equals(wallet.getScriptType()) && !head.isPrivateKey()).findFirst().orElse(ExtendedKey.Header.xpub);
+            address.address = wallet.getKeystores().get(0).getExtendedPublicKey().toString(header);
+            address.account_index = wallet.getNode(KeyPurpose.RECEIVE).getHighestUsedIndex() == null ? 0 : wallet.getNode(KeyPurpose.RECEIVE).getHighestUsedIndex() + 1;
+            address.change_index = wallet.getNode(KeyPurpose.CHANGE).getHighestUsedIndex() == null ? 0 : wallet.getNode(KeyPurpose.CHANGE).getHighestUsedIndex() + 1;
+            address.n_tx = wallet.getTransactions().size();
+            addresses.add(address);
+
+            for(Map.Entry<BlockTransactionHashIndex, WalletNode> utxo : wallet.getWalletUtxos().entrySet()) {
+                BlockTransaction blockTransaction = wallet.getTransactions().get(utxo.getKey().getHash());
+                if(blockTransaction != null) {
+                    unspentOutputs.add(Whirlpool.getUnspentOutput(wallet, utxo.getValue(), blockTransaction, (int)utxo.getKey().getIndex()));
+                }
+            }
+        }
+
+        for(BlockTransaction blockTransaction : allTransactions.values()) {
+            WalletResponse.Tx tx = new WalletResponse.Tx();
+            tx.block_height = blockTransaction.getHeight();
+            tx.hash = blockTransaction.getHashAsString();
+            tx.locktime = blockTransaction.getTransaction().getLocktime();
+            tx.version = (int)blockTransaction.getTransaction().getVersion();
+
+            tx.inputs = new WalletResponse.TxInput[blockTransaction.getTransaction().getInputs().size()];
+            for(int i = 0; i < blockTransaction.getTransaction().getInputs().size(); i++) {
+                TransactionInput txInput = blockTransaction.getTransaction().getInputs().get(i);
+                tx.inputs[i] = new WalletResponse.TxInput();
+                tx.inputs[i].vin = txInput.getIndex();
+                tx.inputs[i].sequence = txInput.getSequenceNumber();
+                if(allTransactionsZpubs.containsKey(txInput.getOutpoint().getHash())) {
+                    tx.inputs[i].prev_out = new WalletResponse.TxOut();
+                    tx.inputs[i].prev_out.txid = txInput.getOutpoint().getHash().toString();
+                    tx.inputs[i].prev_out.vout = (int)txInput.getOutpoint().getIndex();
+
+                    BlockTransaction spentTransaction = allTransactions.get(txInput.getOutpoint().getHash());
+                    if(spentTransaction != null) {
+                        TransactionOutput spentOutput = spentTransaction.getTransaction().getOutputs().get((int)txInput.getOutpoint().getIndex());
+                        tx.inputs[i].prev_out.value = spentOutput.getValue();
+                    }
+
+                    tx.inputs[i].prev_out.xpub = new UnspentOutput.Xpub();
+                    tx.inputs[i].prev_out.xpub.m = allTransactionsZpubs.get(txInput.getOutpoint().getHash());
+                }
+            }
+
+            tx.out = new WalletResponse.TxOutput[blockTransaction.getTransaction().getOutputs().size()];
+            for(int i = 0; i < blockTransaction.getTransaction().getOutputs().size(); i++) {
+                TransactionOutput txOutput = blockTransaction.getTransaction().getOutputs().get(i);
+                tx.out[i] = new WalletResponse.TxOutput();
+                tx.out[i].n = txOutput.getIndex();
+                tx.out[i].value = txOutput.getValue();
+                tx.out[i].xpub = new UnspentOutput.Xpub();
+                tx.out[i].xpub.m = allTransactionsZpubs.get(blockTransaction.getHash());
+            }
+
+            txes.add(tx);
+        }
+
+        walletResponse.addresses = addresses.toArray(new WalletResponse.Address[0]);
+        walletResponse.txs = txes.toArray(new WalletResponse.Tx[0]);
+        walletResponse.unspent_outputs = unspentOutputs.toArray(new UnspentOutput[0]);
+
+        walletResponse.info = new WalletResponse.Info();
+        walletResponse.info.latest_block = new WalletResponse.InfoBlock();
+        walletResponse.info.latest_block.height = AppServices.getCurrentBlockHeight() == null ? storedBlockHeight : AppServices.getCurrentBlockHeight();
+        walletResponse.info.latest_block.hash = Sha256Hash.ZERO_HASH.toString();
+        walletResponse.info.latest_block.time = AppServices.getLatestBlockHeader() == null ? 1 : AppServices.getLatestBlockHeader().getTime();
+
+        walletResponse.info.fees = new LinkedHashMap<>();
+        for(MinerFeeTarget target : MinerFeeTarget.values()) {
+            walletResponse.info.fees.put(target.getValue(), AppServices.getTargetBlockFeeRates() == null ? FALLBACK_FEE_RATE : getMinimumFeeForTarget(Integer.parseInt(target.getValue())));
+        }
+
+        return walletResponse;
+    }
+
+    @Override
+    public MinerFee fetchMinerFee() throws Exception {
+        Map<String, Integer> fees = new LinkedHashMap<>();
+        for(MinerFeeTarget target : MinerFeeTarget.values()) {
+           fees.put(target.getValue(), AppServices.getTargetBlockFeeRates() == null ? FALLBACK_FEE_RATE : getMinimumFeeForTarget(Integer.parseInt(target.getValue())));
+        }
+
+        return new MinerFee(fees);
+    }
+
+    @Override
+    public void pushTx(String txHex) throws Exception {
+        Transaction transaction = new Transaction(Utils.hexToBytes(txHex));
+        ElectrumServer electrumServer = new ElectrumServer();
+        electrumServer.broadcastTransactionPrivately(transaction);
+    }
+
+    @Override
+    public boolean testConnectivity() {
+        return AppServices.isConnected();
+    }
+
+    private Integer getMinimumFeeForTarget(int targetBlocks) {
+        List<Map.Entry<Integer, Double>> feeRates = new ArrayList<>(AppServices.getTargetBlockFeeRates().entrySet());
+        Collections.reverse(feeRates);
+        for(Map.Entry<Integer, Double> feeRate : feeRates) {
+            if(feeRate.getKey() <= targetBlocks) {
+                return feeRate.getValue().intValue();
+            }
+        }
+
+        return feeRates.get(0).getValue().intValue();
+    }
+
+    @Override
+    public void initBip84(String zpub) throws Exception {
+        //nothing required
+    }
+
+    private Wallet getWallet(String zpub) {
+        return AppServices.get().getOpenWallets().keySet().stream()
+                .filter(wallet -> {
+                    List<ExtendedKey.Header> headers = ExtendedKey.Header.getHeaders(Network.get());
+                    ExtendedKey.Header header = headers.stream().filter(head -> head.getDefaultScriptType().equals(wallet.getScriptType()) && !head.isPrivateKey()).findFirst().orElse(ExtendedKey.Header.xpub);
+                    ExtendedKey.Header p2pkhHeader = headers.stream().filter(head -> head.getDefaultScriptType().equals(ScriptType.P2PKH) && !head.isPrivateKey()).findFirst().orElse(ExtendedKey.Header.xpub);
+                    ExtendedKey extPubKey = wallet.getKeystores().get(0).getExtendedPublicKey();
+                    return extPubKey.toString(header).equals(zpub) || extPubKey.toString(p2pkhHeader).equals(zpub);
+                })
+                .findFirst()
+                .orElse(null);
+    }
+
+    @Override
+    public List<UnspentOutput> fetchUtxos(String zpub) throws Exception {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public List<UnspentOutput> fetchUtxos(String[] zpubs) throws Exception {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public Map<String, MultiAddrResponse.Address> fetchAddresses(String[] zpubs) throws Exception {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public MultiAddrResponse.Address fetchAddress(String zpub) throws Exception {
+        throw new UnsupportedOperationException();
+    }
+}

src/main/java/com/sparrowwallet/sparrow/whirlpool/SparrowMinerFeeSupplier.java

@@ -0,0 +1,11 @@
+package com.sparrowwallet.sparrow.whirlpool;
+
+import com.samourai.wallet.api.backend.MinerFee;
+import com.samourai.whirlpool.client.wallet.data.minerFee.MinerFeeSupplier;
+
+public class SparrowMinerFeeSupplier extends MinerFeeSupplier {
+    public SparrowMinerFeeSupplier(int feeMin, int feeMax, int feeFallback, MinerFee currentMinerFee) {
+        super(feeMin, feeMax, feeFallback);
+        setValue(currentMinerFee);
+    }
+}

src/main/java/com/sparrowwallet/sparrow/whirlpool/Whirlpool.java

@@ -0,0 +1,361 @@
+package com.sparrowwallet.sparrow.whirlpool;
+
+import com.google.common.eventbus.Subscribe;
+import com.google.common.net.HostAndPort;
+import com.samourai.tor.client.TorClientService;
+import com.samourai.wallet.api.backend.BackendApi;
+import com.samourai.wallet.api.backend.beans.UnspentOutput;
+import com.samourai.wallet.hd.HD_Wallet;
+import com.samourai.wallet.hd.java.HD_WalletFactoryJava;
+import com.samourai.whirlpool.client.event.*;
+import com.samourai.whirlpool.client.tx0.*;
+import com.samourai.whirlpool.client.wallet.WhirlpoolEventService;
+import com.samourai.whirlpool.client.wallet.WhirlpoolWallet;
+import com.samourai.whirlpool.client.wallet.WhirlpoolWalletConfig;
+import com.samourai.whirlpool.client.wallet.WhirlpoolWalletService;
+import com.samourai.whirlpool.client.wallet.beans.*;
+import com.samourai.whirlpool.client.wallet.data.pool.PoolData;
+import com.samourai.whirlpool.client.wallet.data.utxo.UtxoSupplier;
+import com.samourai.whirlpool.client.whirlpool.ServerApi;
+import com.samourai.whirlpool.client.whirlpool.beans.Pool;
+import com.sparrowwallet.drongo.ExtendedKey;
+import com.sparrowwallet.drongo.Network;
+import com.sparrowwallet.drongo.Utils;
+import com.sparrowwallet.drongo.protocol.ScriptType;
+import com.sparrowwallet.drongo.protocol.Sha256Hash;
+import com.sparrowwallet.drongo.protocol.Transaction;
+import com.sparrowwallet.drongo.protocol.TransactionOutput;
+import com.sparrowwallet.drongo.wallet.*;
+import com.sparrowwallet.nightjar.http.JavaHttpClientService;
+import com.sparrowwallet.nightjar.stomp.JavaStompClientService;
+import com.sparrowwallet.nightjar.tor.WhirlpoolTorClientService;
+import com.sparrowwallet.sparrow.AppServices;
+import com.sparrowwallet.sparrow.wallet.UtxoEntry;
+import javafx.concurrent.Service;
+import javafx.concurrent.Task;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.*;
+import java.util.stream.Collectors;
+
+public class Whirlpool {
+    private static final Logger log = LoggerFactory.getLogger(Whirlpool.class);
+
+    private final HostAndPort torProxy;
+    private final WhirlpoolServer whirlpoolServer;
+    private final JavaHttpClientService httpClientService;
+    private final JavaStompClientService stompClientService;
+    private final TorClientService torClientService;
+    private final WhirlpoolWalletService whirlpoolWalletService;
+    private final WhirlpoolWalletConfig config;
+    private HD_Wallet hdWallet;
+
+    public Whirlpool(Network network, HostAndPort torProxy, String sCode, int maxClients, int clientDelay) {
+        this.torProxy = torProxy;
+        this.whirlpoolServer = WhirlpoolServer.valueOf(network.getName().toUpperCase());
+        this.httpClientService = new JavaHttpClientService(torProxy);
+        this.stompClientService = new JavaStompClientService(httpClientService);
+        this.torClientService = new WhirlpoolTorClientService();
+        this.whirlpoolWalletService = new WhirlpoolWalletService();
+        this.config = computeWhirlpoolWalletConfig(sCode, maxClients, clientDelay);
+
+        WhirlpoolEventService.getInstance().register(this);
+    }
+
+    private WhirlpoolWalletConfig computeWhirlpoolWalletConfig(String sCode, int maxClients, int clientDelay) {
+        boolean onion = (torProxy != null);
+        String serverUrl = whirlpoolServer.getServerUrl(onion);
+
+        ServerApi serverApi = new ServerApi(serverUrl, httpClientService);
+        BackendApi backendApi = new SparrowBackendApi();
+
+        WhirlpoolWalletConfig whirlpoolWalletConfig = new WhirlpoolWalletConfig(httpClientService, stompClientService, torClientService, serverApi, whirlpoolServer, false, backendApi);
+        whirlpoolWalletConfig.setScode(sCode);
+
+        return whirlpoolWalletConfig;
+    }
+
+    public Collection<Pool> getPools() throws Exception {
+        Tx0ParamService tx0ParamService = getTx0ParamService();
+        PoolData poolData = new PoolData(config.getServerApi().fetchPools(), tx0ParamService);
+        return poolData.getPools();
+    }
+
+    public Tx0Preview getTx0Preview(Pool pool, Collection<UnspentOutput> utxos) throws Exception {
+        Tx0Config tx0Config = new Tx0Config();
+        tx0Config.setChangeWallet(WhirlpoolAccount.BADBANK);
+        Tx0FeeTarget tx0FeeTarget = Tx0FeeTarget.BLOCKS_4;
+        Tx0FeeTarget mixFeeTarget = Tx0FeeTarget.BLOCKS_4;
+
+        Tx0ParamService tx0ParamService = getTx0ParamService();
+
+        Tx0Service tx0Service = new Tx0Service(config);
+        return tx0Service.tx0Preview(utxos, tx0Config, tx0ParamService.getTx0Param(pool, tx0FeeTarget, mixFeeTarget));
+    }
+
+    public Tx0 broadcastTx0(Pool pool, Collection<BlockTransactionHashIndex> utxos) throws Exception {
+        WhirlpoolWallet whirlpoolWallet = getWhirlpoolWallet();
+        whirlpoolWallet.start();
+        UtxoSupplier utxoSupplier = whirlpoolWallet.getUtxoSupplier();
+        List<WhirlpoolUtxo> whirlpoolUtxos = utxos.stream().map(ref -> utxoSupplier.findUtxo(ref.getHashAsString(), (int)ref.getIndex())).filter(Objects::nonNull).collect(Collectors.toList());
+
+        if(whirlpoolUtxos.size() != utxos.size()) {
+            throw new IllegalStateException("Failed to find UTXOs in Whirlpool wallet");
+        }
+
+        Tx0Config tx0Config = new Tx0Config();
+        tx0Config.setChangeWallet(WhirlpoolAccount.BADBANK);
+        Tx0FeeTarget tx0FeeTarget = Tx0FeeTarget.BLOCKS_4;
+        Tx0FeeTarget mixFeeTarget = Tx0FeeTarget.BLOCKS_4;
+
+        return whirlpoolWallet.tx0(whirlpoolUtxos, pool, tx0Config, tx0FeeTarget, mixFeeTarget);
+    }
+
+    private Tx0ParamService getTx0ParamService() {
+        try {
+            SparrowMinerFeeSupplier minerFeeSupplier = new SparrowMinerFeeSupplier(config.getFeeMin(), config.getFeeMax(), config.getFeeFallback(), config.getBackendApi().fetchMinerFee());
+            return new Tx0ParamService(minerFeeSupplier, config);
+        } catch(Exception e) {
+            log.error("Error fetching miner fees", e);
+        }
+
+        return null;
+    }
+
+    public void setHDWallet(Wallet wallet) {
+        if(wallet.isEncrypted()) {
+            throw new IllegalStateException("Wallet cannot be encrypted");
+        }
+
+        try {
+            Keystore keystore = wallet.getKeystores().get(0);
+            ScriptType scriptType = wallet.getScriptType();
+            int purpose = scriptType.getDefaultDerivation().get(0).num();
+            List<String> words = keystore.getSeed().getMnemonicCode();
+            String passphrase = keystore.getSeed().getPassphrase().asString();
+            HD_WalletFactoryJava hdWalletFactory = HD_WalletFactoryJava.getInstance();
+            byte[] seed = hdWalletFactory.computeSeedFromWords(words);
+            hdWallet = new HD_Wallet(purpose, words, whirlpoolServer, seed, passphrase, 1);
+        } catch(Exception e) {
+            throw new IllegalStateException("Could not create Whirlpool HD wallet ", e);
+        }
+    }
+
+    public WhirlpoolWallet getWhirlpoolWallet() throws WhirlpoolException {
+        if(whirlpoolWalletService.whirlpoolWallet() != null) {
+            return whirlpoolWalletService.whirlpoolWallet();
+        }
+
+        if(hdWallet == null) {
+            throw new IllegalStateException("Whirlpool HD wallet not added");
+        }
+
+        try {
+            return whirlpoolWalletService.openWallet(config, Utils.hexToBytes(hdWallet.getSeedHex()), hdWallet.getPassphrase());
+        } catch(Exception e) {
+            throw new WhirlpoolException("Could not create whirlpool wallet ", e);
+        }
+    }
+
+    public HostAndPort getTorProxy() {
+        return torProxy;
+    }
+
+    public boolean hasWallet() {
+        return hdWallet != null;
+    }
+
+    public boolean isStarted() {
+        if(whirlpoolWalletService.whirlpoolWallet() == null) {
+            return false;
+        }
+
+        return whirlpoolWalletService.whirlpoolWallet().isStarted();
+    }
+
+    public void shutdown() {
+        whirlpoolWalletService.closeWallet();
+        httpClientService.shutdown();
+    }
+
+    public static UnspentOutput getUnspentOutput(Wallet wallet, WalletNode node, BlockTransaction blockTransaction, int index) {
+        TransactionOutput txOutput = blockTransaction.getTransaction().getOutputs().get(index);
+
+        UnspentOutput out = new UnspentOutput();
+        out.tx_hash = txOutput.getHash().toString();
+        out.tx_output_n = txOutput.getIndex();
+        out.value = txOutput.getValue();
+        out.script = Utils.bytesToHex(txOutput.getScriptBytes());
+
+        try {
+            out.addr = txOutput.getScript().getToAddresses()[0].toString();
+        } catch(Exception e) {
+            //ignore
+        }
+
+        Transaction transaction = (Transaction)txOutput.getParent();
+        out.tx_version = (int)transaction.getVersion();
+        out.tx_locktime = transaction.getLocktime();
+        if(AppServices.getCurrentBlockHeight() != null) {
+            out.confirmations = blockTransaction.getConfirmations(AppServices.getCurrentBlockHeight());
+        }
+
+        if(wallet.getKeystores().size() != 1) {
+            throw new IllegalStateException("Cannot mix outputs from a wallet with multiple keystores");
+        }
+
+        UnspentOutput.Xpub xpub = new UnspentOutput.Xpub();
+        List<ExtendedKey.Header> headers = ExtendedKey.Header.getHeaders(Network.get());
+        ExtendedKey.Header header = headers.stream().filter(head -> head.getDefaultScriptType().equals(wallet.getScriptType()) && !head.isPrivateKey()).findFirst().orElse(ExtendedKey.Header.xpub);
+        xpub.m = wallet.getKeystores().get(0).getExtendedPublicKey().toString(header);
+        xpub.path = node.getDerivationPath().toUpperCase();
+
+        out.xpub = xpub;
+
+        return out;
+    }
+
+    public String getScode() {
+        return config.getScode();
+    }
+
+    public void setScode(String scode) {
+        config.setScode(scode);
+    }
+
+    @Subscribe
+    public void onMixFail(MixFailEvent e) {
+        log.info("Mix failed for utxo " + e.getWhirlpoolUtxo().getUtxo().tx_hash + ":" + e.getWhirlpoolUtxo().getUtxo().tx_output_n);
+    }
+
+    @Subscribe
+    public void onMixSuccess(MixSuccessEvent e) {
+        log.info("Mix success, new utxo " + e.getMixSuccess().getReceiveUtxo().getHash() + ":" + e.getMixSuccess().getReceiveUtxo().getIndex());
+    }
+
+    @Subscribe
+    public void onWalletStart(WalletStartEvent e) {
+        log.info("Wallet started");
+    }
+
+    @Subscribe
+    public void onWalletStop(WalletStopEvent e) {
+        log.info("Wallet stopped");
+    }
+
+    public static class PoolsService extends Service<Collection<Pool>> {
+        private final Whirlpool whirlpool;
+
+        public PoolsService(Whirlpool whirlpool) {
+            this.whirlpool = whirlpool;
+        }
+
+        @Override
+        protected Task<Collection<Pool>> createTask() {
+            return new Task<>() {
+                protected Collection<Pool> call() throws Exception {
+                    return whirlpool.getPools();
+                }
+            };
+        }
+    }
+
+    public static class Tx0PreviewService extends Service<Tx0Preview> {
+        private final Whirlpool whirlpool;
+        private final Wallet wallet;
+        private final Pool pool;
+        private final List<UtxoEntry> utxoEntries;
+
+        public Tx0PreviewService(Whirlpool whirlpool, Wallet wallet, Pool pool, List<UtxoEntry> utxoEntries) {
+            this.whirlpool = whirlpool;
+            this.wallet = wallet;
+            this.pool = pool;
+            this.utxoEntries = utxoEntries;
+        }
+
+        @Override
+        protected Task<Tx0Preview> createTask() {
+            return new Task<>() {
+                protected Tx0Preview call() throws Exception {
+                    updateProgress(-1, 1);
+                    updateMessage("Fetching premix transaction...");
+
+                    Collection<UnspentOutput> utxos = utxoEntries.stream().map(utxoEntry -> Whirlpool.getUnspentOutput(wallet, utxoEntry.getNode(), utxoEntry.getBlockTransaction(), (int)utxoEntry.getHashIndex().getIndex())).collect(Collectors.toList());
+                    return whirlpool.getTx0Preview(pool, utxos);
+                }
+            };
+        }
+    }
+
+    public static class Tx0BroadcastService extends Service<Sha256Hash> {
+        private final Whirlpool whirlpool;
+        private final Pool pool;
+        private final Collection<BlockTransactionHashIndex> utxos;
+
+        public Tx0BroadcastService(Whirlpool whirlpool, Pool pool, Collection<BlockTransactionHashIndex> utxos) {
+            this.whirlpool = whirlpool;
+            this.pool = pool;
+            this.utxos = utxos;
+        }
+
+        @Override
+        protected Task<Sha256Hash> createTask() {
+            return new Task<>() {
+                protected Sha256Hash call() throws Exception {
+                    updateProgress(-1, 1);
+                    updateMessage("Broadcasting premix transaction...");
+
+                    Tx0 tx0 = whirlpool.broadcastTx0(pool, utxos);
+                    return Sha256Hash.wrap(tx0.getTxid());
+                }
+            };
+        }
+    }
+
+    public static class StartupService extends Service<WhirlpoolWallet> {
+        private final Whirlpool whirlpool;
+
+        public StartupService(Whirlpool whirlpool) {
+            this.whirlpool = whirlpool;
+        }
+
+        @Override
+        protected Task<WhirlpoolWallet> createTask() {
+            return new Task<>() {
+                protected WhirlpoolWallet call() throws Exception {
+                    updateProgress(-1, 1);
+                    updateMessage("Starting Whirlpool...");
+
+                    WhirlpoolWallet whirlpoolWallet = whirlpool.getWhirlpoolWallet();
+                    if(AppServices.onlineProperty().get()) {
+                        whirlpoolWallet.start();
+                    }
+
+                    return whirlpoolWallet;
+                }
+            };
+        }
+    }
+
+    public static class ShutdownService extends Service<Boolean> {
+        private final Whirlpool whirlpool;
+
+        public ShutdownService(Whirlpool whirlpool) {
+            this.whirlpool = whirlpool;
+        }
+
+        @Override
+        protected Task<Boolean> createTask() {
+            return new Task<>() {
+                protected Boolean call() throws Exception {
+                    updateProgress(-1, 1);
+                    updateMessage("Disconnecting from Whirlpool...");
+
+                    whirlpool.shutdown();
+                    return true;
+                }
+            };
+        }
+    }
+}

src/main/java/com/sparrowwallet/sparrow/whirlpool/WhirlpoolController.java

@@ -0,0 +1,253 @@
+package com.sparrowwallet.sparrow.whirlpool;
+
+import com.samourai.whirlpool.client.tx0.Tx0Preview;
+import com.samourai.whirlpool.client.whirlpool.beans.Pool;
+import com.sparrowwallet.drongo.BitcoinUnit;
+import com.sparrowwallet.drongo.protocol.Transaction;
+import com.sparrowwallet.drongo.wallet.Wallet;
+import com.sparrowwallet.sparrow.AppServices;
+import com.sparrowwallet.sparrow.control.CoinLabel;
+import com.sparrowwallet.sparrow.io.Config;
+import com.sparrowwallet.sparrow.wallet.Entry;
+import com.sparrowwallet.sparrow.wallet.UtxoEntry;
+import javafx.beans.property.ObjectProperty;
+import javafx.beans.property.SimpleObjectProperty;
+import javafx.collections.FXCollections;
+import javafx.fxml.FXML;
+import javafx.scene.control.*;
+import javafx.scene.layout.HBox;
+import javafx.scene.layout.VBox;
+import javafx.util.StringConverter;
+
+import java.util.*;
+
+public class WhirlpoolController {
+    @FXML
+    private VBox whirlpoolBox;
+
+    @FXML
+    private VBox step1;
+
+    @FXML
+    private VBox step2;
+
+    @FXML
+    private VBox step3;
+
+    @FXML
+    private VBox step4;
+
+    @FXML
+    private TextField scode;
+
+    @FXML
+    private ComboBox<Pool> pool;
+
+    @FXML
+    private VBox selectedPool;
+
+    @FXML
+    private CoinLabel poolFee;
+
+    @FXML
+    private Label poolInsufficient;
+
+    @FXML
+    private Label poolAnonset;
+
+    @FXML
+    private HBox discountFeeBox;
+
+    @FXML
+    private HBox nbOutputsBox;
+
+    @FXML
+    private Label nbOutputsLoading;
+
+    @FXML
+    private Label nbOutputs;
+
+    @FXML
+    private CoinLabel discountFee;
+
+    private String walletId;
+    private Wallet wallet;
+    private List<UtxoEntry> utxoEntries;
+    private final ObjectProperty<Tx0Preview> tx0PreviewProperty = new SimpleObjectProperty<>(null);
+
+    public void initializeView(String walletId, Wallet wallet, List<UtxoEntry> utxoEntries) {
+        this.walletId = walletId;
+        this.wallet = wallet;
+        this.utxoEntries = utxoEntries;
+
+        step1.managedProperty().bind(step1.visibleProperty());
+        step2.managedProperty().bind(step2.visibleProperty());
+        step3.managedProperty().bind(step3.visibleProperty());
+        step4.managedProperty().bind(step4.visibleProperty());
+
+        step2.setVisible(false);
+        step3.setVisible(false);
+        step4.setVisible(false);
+
+        scode.setText(Config.get().getScode() == null ? "" : Config.get().getScode());
+        scode.textProperty().addListener((observable, oldValue, newValue) -> {
+            Config.get().setScode(newValue);
+        });
+
+        pool.setConverter(new StringConverter<Pool>() {
+            @Override
+            public String toString(Pool pool) {
+                return pool == null ? "Fetching pools..." : pool.getPoolId().replace("btc", " BTC");
+            }
+
+            @Override
+            public Pool fromString(String string) {
+                return null;
+            }
+        });
+
+        pool.valueProperty().addListener((observable, oldValue, newValue) -> {
+            if(newValue == null) {
+                selectedPool.setVisible(false);
+            } else {
+                poolFee.setValue(newValue.getFeeValue());
+                poolAnonset.setText(newValue.getMixAnonymitySet() + " UTXOs");
+                selectedPool.setVisible(true);
+                fetchTx0Preview(newValue);
+            }
+        });
+
+        step4.visibleProperty().addListener((observable, oldValue, newValue) -> {
+            if(newValue && pool.getItems().isEmpty()) {
+                fetchPools();
+            }
+        });
+
+        selectedPool.managedProperty().bind(selectedPool.visibleProperty());
+        selectedPool.setVisible(false);
+        pool.managedProperty().bind(pool.visibleProperty());
+        poolInsufficient.managedProperty().bind(poolInsufficient.visibleProperty());
+        poolInsufficient.visibleProperty().bind(pool.visibleProperty().not());
+        discountFeeBox.managedProperty().bind(discountFeeBox.visibleProperty());
+        discountFeeBox.setVisible(false);
+        nbOutputsBox.managedProperty().bind(nbOutputsBox.visibleProperty());
+        nbOutputsBox.setVisible(false);
+        nbOutputsLoading.managedProperty().bind(nbOutputsLoading.visibleProperty());
+        nbOutputs.managedProperty().bind(nbOutputs.visibleProperty());
+        nbOutputsLoading.visibleProperty().bind(nbOutputs.visibleProperty().not());
+        nbOutputs.setVisible(false);
+    }
+
+    public boolean next() {
+        if(step1.isVisible()) {
+            step1.setVisible(false);
+            step2.setVisible(true);
+            return true;
+        }
+
+        if(step2.isVisible()) {
+            step2.setVisible(false);
+            step3.setVisible(true);
+            return true;
+        }
+
+        if(step3.isVisible()) {
+            step3.setVisible(false);
+            step4.setVisible(true);
+        }
+
+        return false;
+    }
+
+    public boolean back() {
+        if(step2.isVisible()) {
+            step2.setVisible(false);
+            step1.setVisible(true);
+            return false;
+        }
+
+        if(step3.isVisible()) {
+            step3.setVisible(false);
+            step2.setVisible(true);
+            return true;
+        }
+
+        if(step4.isVisible()) {
+            step4.setVisible(false);
+            step3.setVisible(true);
+            return true;
+        }
+
+        return false;
+    }
+
+    private void fetchPools() {
+        long totalUtxoValue = utxoEntries.stream().mapToLong(Entry::getValue).sum();
+        Whirlpool.PoolsService poolsService = new Whirlpool.PoolsService(AppServices.get().getWhirlpool(walletId));
+        poolsService.setOnSucceeded(workerStateEvent -> {
+            List<Pool> availablePools = poolsService.getValue().stream().filter(pool1 -> totalUtxoValue >= (pool1.getPremixValueMin() + pool1.getFeeValue())).toList();
+            if(availablePools.isEmpty()) {
+                pool.setVisible(false);
+                OptionalLong optMinValue = poolsService.getValue().stream().mapToLong(Pool::getMustMixBalanceMin).min();
+                if(optMinValue.isPresent()) {
+                    String satsValue = String.format(Locale.ENGLISH, "%,d", optMinValue.getAsLong()) + " sats";
+                    String btcValue = CoinLabel.BTC_FORMAT.format((double)optMinValue.getAsLong() / Transaction.SATOSHIS_PER_BITCOIN) + " BTC";
+                    poolInsufficient.setText("No available pools. Select a value over " + (Config.get().getBitcoinUnit() == BitcoinUnit.BTC ? btcValue : satsValue) + ".");
+                }
+            } else {
+                pool.setDisable(false);
+                pool.setItems(FXCollections.observableList(availablePools));
+                pool.getSelectionModel().select(0);
+            }
+        });
+        poolsService.setOnFailed(workerStateEvent -> {
+            Throwable exception = workerStateEvent.getSource().getException();
+            while(exception.getCause() != null) {
+                exception = exception.getCause();
+            }
+
+            Optional<ButtonType> optButton = AppServices.showErrorDialog("Error fetching pools", exception.getMessage(), ButtonType.CANCEL, new ButtonType("Retry", ButtonBar.ButtonData.APPLY));
+            if(optButton.isPresent()) {
+                if(optButton.get().getButtonData().equals(ButtonBar.ButtonData.APPLY)) {
+                    fetchPools();
+                } else {
+                    pool.setDisable(true);
+                }
+            }
+        });
+        poolsService.start();
+    }
+
+    private void fetchTx0Preview(Pool pool) {
+        Whirlpool whirlpool = AppServices.get().getWhirlpool(walletId);
+        whirlpool.setScode(Config.get().getScode());
+
+        Whirlpool.Tx0PreviewService tx0PreviewService = new Whirlpool.Tx0PreviewService(whirlpool, wallet, pool, utxoEntries);
+        tx0PreviewService.setOnRunning(workerStateEvent -> {
+            nbOutputsBox.setVisible(true);
+            nbOutputsLoading.setText("Calculating...");
+        });
+        tx0PreviewService.setOnSucceeded(workerStateEvent -> {
+            Tx0Preview tx0Preview = tx0PreviewService.getValue();
+            discountFeeBox.setVisible(tx0Preview.getPool().getFeeValue() != tx0Preview.getTx0Data().getFeeValue());
+            discountFee.setValue(tx0Preview.getTx0Data().getFeeValue());
+            nbOutputsBox.setVisible(true);
+            nbOutputs.setText(tx0Preview.getNbPremix() + " UTXOs");
+            nbOutputs.setVisible(true);
+            tx0PreviewProperty.set(tx0Preview);
+        });
+        tx0PreviewService.setOnFailed(workerStateEvent -> {
+            Throwable exception = workerStateEvent.getSource().getException();
+            while(exception.getCause() != null) {
+                exception = exception.getCause();
+            }
+
+            nbOutputsLoading.setText("Error fetching fee: " + exception.getMessage());
+        });
+        tx0PreviewService.start();
+    }
+
+    public ObjectProperty<Tx0Preview> getTx0PreviewProperty() {
+        return tx0PreviewProperty;
+    }
+}

src/main/java/com/sparrowwallet/sparrow/whirlpool/WhirlpoolDialog.java

@@ -0,0 +1,81 @@
+package com.sparrowwallet.sparrow.whirlpool;
+
+import com.samourai.whirlpool.client.tx0.Tx0Preview;
+import com.samourai.whirlpool.client.whirlpool.beans.Pool;
+import com.sparrowwallet.drongo.wallet.Wallet;
+import com.sparrowwallet.sparrow.AppServices;
+import com.sparrowwallet.sparrow.wallet.UtxoEntry;
+import javafx.beans.value.ChangeListener;
+import javafx.beans.value.ObservableValue;
+import javafx.event.ActionEvent;
+import javafx.fxml.FXMLLoader;
+import javafx.scene.control.*;
+
+import java.io.IOException;
+import java.util.List;
+
+public class WhirlpoolDialog extends Dialog<Tx0Preview> {
+    public WhirlpoolDialog(String walletId, Wallet wallet, List<UtxoEntry> utxoEntries) {
+        final DialogPane dialogPane = getDialogPane();
+        AppServices.setStageIcon(dialogPane.getScene().getWindow());
+        AppServices.onEscapePressed(dialogPane.getScene(), this::close);
+
+        try {
+            FXMLLoader whirlpoolLoader = new FXMLLoader(AppServices.class.getResource("whirlpool/whirlpool.fxml"));
+            dialogPane.setContent(whirlpoolLoader.load());
+            WhirlpoolController whirlpoolController = whirlpoolLoader.getController();
+            whirlpoolController.initializeView(walletId, wallet, utxoEntries);
+
+            dialogPane.setPrefWidth(600);
+            dialogPane.setPrefHeight(520);
+            AppServices.moveToActiveWindowScreen(this);
+
+            dialogPane.getStylesheets().add(AppServices.class.getResource("whirlpool/whirlpool.css").toExternalForm());
+
+            final ButtonType nextButtonType = new javafx.scene.control.ButtonType("Next", ButtonBar.ButtonData.OK_DONE);
+            final ButtonType backButtonType = new javafx.scene.control.ButtonType("Back", ButtonBar.ButtonData.LEFT);
+            final ButtonType cancelButtonType = new javafx.scene.control.ButtonType("Cancel", ButtonBar.ButtonData.CANCEL_CLOSE);
+            final ButtonType previewButtonType = new javafx.scene.control.ButtonType("Preview Premix", ButtonBar.ButtonData.APPLY);
+            dialogPane.getButtonTypes().addAll(nextButtonType, backButtonType, cancelButtonType, previewButtonType);
+
+            Button nextButton = (Button)dialogPane.lookupButton(nextButtonType);
+            Button backButton = (Button)dialogPane.lookupButton(backButtonType);
+            Button previewButton = (Button)dialogPane.lookupButton(previewButtonType);
+            previewButton.setDisable(true);
+            whirlpoolController.getTx0PreviewProperty().addListener(new ChangeListener<Tx0Preview>() {
+                @Override
+                public void changed(ObservableValue<? extends Tx0Preview> observable, Tx0Preview oldValue, Tx0Preview newValue) {
+                    previewButton.setDisable(newValue == null);
+                }
+            });
+
+            nextButton.managedProperty().bind(nextButton.visibleProperty());
+            backButton.managedProperty().bind(backButton.visibleProperty());
+            previewButton.managedProperty().bind(previewButton.visibleProperty());
+
+            backButton.setDisable(true);
+            previewButton.visibleProperty().bind(nextButton.visibleProperty().not());
+
+            nextButton.addEventFilter(ActionEvent.ACTION, event -> {
+                if(!whirlpoolController.next()) {
+                    nextButton.setVisible(false);
+                    previewButton.setDefaultButton(true);
+                }
+                backButton.setDisable(false);
+                event.consume();
+            });
+
+            backButton.addEventFilter(ActionEvent.ACTION, event -> {
+                nextButton.setVisible(true);
+                if(!whirlpoolController.back()) {
+                    backButton.setDisable(true);
+                }
+                event.consume();
+            });
+
+            setResultConverter(dialogButton -> dialogButton.getButtonData().equals(ButtonBar.ButtonData.APPLY) ? whirlpoolController.getTx0PreviewProperty().get() : null);
+        } catch(IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+}

src/main/java/com/sparrowwallet/sparrow/whirlpool/WhirlpoolException.java

@@ -0,0 +1,11 @@
+package com.sparrowwallet.sparrow.whirlpool;
+
+public class WhirlpoolException extends Exception {
+    public WhirlpoolException(String message) {
+        super(message);
+    }
+
+    public WhirlpoolException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

src/main/java/module-info.java

@@ -37,4 +37,5 @@ open module com.sparrowwallet.sparrow {
     requires com.nativelibs4java.bridj;
     requires org.reactfx.reactfx;
     requires dev.bwt.jni;
+    requires com.sparrowwallet.nightjar;
 }