automatically switch between internal and external tor proxy as required when connecting to server

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

@@ -1633,6 +1633,12 @@ public class AppController implements Initializable {
         statusUpdated(new StatusEvent(event.getStatus()));
     }
 
+    @Subscribe
+    public void torExternalStatus(TorExternalStatusEvent event) {
+        serverToggle.setDisable(false);
+        statusUpdated(new StatusEvent(event.getStatus()));
+    }
+
     @Subscribe
     public void newBlock(NewBlockEvent event) {
         setServerToggleTooltip(event.getHeight());

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

@@ -94,7 +94,7 @@ public class AppServices {
         @Override
         public void changed(ObservableValue<? extends Boolean> observable, Boolean oldValue, Boolean online) {
             if(online) {
-                if(Config.get().requiresTor() && !isTorRunning()) {
+                if(Config.get().requiresInternalTor() && !isTorRunning()) {
                     torService.start();
                 } else {
                     restartServices();
@@ -122,7 +122,7 @@ public class AppServices {
         onlineProperty.addListener(onlineServicesListener);
 
         if(config.getMode() == Mode.ONLINE) {
-            if(config.requiresTor()) {
+            if(config.requiresInternalTor()) {
                 torService.start();
             } else {
                 restartServices();
@@ -233,6 +233,12 @@ public class AppServices {
                 }
             }
 
+            if(failEvent.getSource().getException() instanceof ProxyServerException && Config.get().isUseProxy() && Config.get().requiresTor()) {
+                Config.get().setUseProxy(false);
+                Platform.runLater(() -> restartService(torService));
+                return;
+            }
+
             onlineProperty.removeListener(onlineServicesListener);
             onlineProperty.setValue(false);
             onlineProperty.addListener(onlineServicesListener);
@@ -314,6 +320,23 @@ public class AppServices {
             EventManager.get().post(new TorReadyStatusEvent());
         });
         torService.setOnFailed(workerStateEvent -> {
+            Throwable exception = workerStateEvent.getSource().getException();
+            if(exception instanceof TorServerAlreadyBoundException) {
+                String proxyServer = Config.get().getProxyServer();
+                if(proxyServer == null || proxyServer.equals("")) {
+                    proxyServer = "localhost:9050";
+                    Config.get().setProxyServer(proxyServer);
+                }
+
+                if(proxyServer.equals("localhost:9050") || proxyServer.equals("127.0.0.1:9050")) {
+                    Config.get().setUseProxy(true);
+                    torService.cancel();
+                    restartServices();
+                    EventManager.get().post(new TorExternalStatusEvent());
+                    return;
+                }
+            }
+
             EventManager.get().post(new TorFailedStatusEvent(workerStateEvent.getSource().getException()));
         });
 

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

@@ -0,0 +1,7 @@
+package com.sparrowwallet.sparrow.event;
+
+public class TorExternalStatusEvent extends TorStatusEvent {
+    public TorExternalStatusEvent() {
+        super("Tor is already running, using external instance...");
+    }
+}

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

@@ -1,12 +1,13 @@
 package com.sparrowwallet.sparrow.event;
 
+import com.sparrowwallet.sparrow.net.TorServerAlreadyBoundException;
+
 public class TorFailedStatusEvent extends TorStatusEvent {
     private final Throwable exception;
 
     public TorFailedStatusEvent(Throwable exception) {
-        super("Tor failed to start: " + (exception.getCause() != null ?
+        super("Tor failed to start: " + (exception instanceof TorServerAlreadyBoundException ? exception.getCause().getMessage() + " Is a Tor proxy already running?" :
-                (exception.getCause().getMessage().contains("Failed to bind") ? exception.getCause().getMessage() + " Is a Tor proxy already running?" : exception.getCause().getMessage() ) :
+                (exception.getCause() != null ? exception.getCause().getMessage() : exception.getMessage())));
-                exception.getMessage()));
         this.exception = exception;
     }
 

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

@@ -303,8 +303,16 @@ public class Config {
         return getServerType() == ServerType.BITCOIN_CORE ? getCoreServer() : (getServerType() == ServerType.PUBLIC_ELECTRUM_SERVER ? getPublicElectrumServer() : getElectrumServer());
     }
 
+    public boolean requiresInternalTor() {
+        if(isUseProxy()) {
+            return false;
+        }
+
+        return requiresTor();
+    }
+
     public boolean requiresTor() {
-        if(isUseProxy() || !hasServerAddress()) {
+        if(!hasServerAddress()) {
             return false;
         }
 

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

@@ -0,0 +1,7 @@
+package com.sparrowwallet.sparrow.net;
+
+public class ProxyServerException extends ServerException {
+    public ProxyServerException(Throwable cause) {
+        super(cause);
+    }
+}

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

@@ -196,6 +196,10 @@ public class TcpTransport implements Transport, Closeable {
         } catch(SSLHandshakeException e) {
             throw new TlsServerException(server, e);
         } catch(IOException e) {
+            if(e.getStackTrace().length > 0 && e.getStackTrace()[0].getClassName().contains("SocksSocketImpl")) {
+                throw new ProxyServerException(e);
+            }
+
             throw new ServerException(e);
         }
     }

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

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

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

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

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

@@ -32,7 +32,7 @@ public class TorService extends ScheduledService<NativeTor> {
     @Override
     protected Task<NativeTor> createTask() {
         return new Task<>() {
-            protected NativeTor call() throws IOException {
+            protected NativeTor call() throws IOException, TorServerException {
                 if(Tor.getDefault() == null) {
                     Path path = Files.createTempDirectory(TOR_DIR_PREFIX);
                     File torInstallDir = path.toFile();
@@ -45,11 +45,15 @@ public class TorService extends ScheduledService<NativeTor> {
 
                         return new NativeTor(torInstallDir, Collections.emptyList(), override);
                     } catch(TorCtlException e) {
-                        log.error("Failed to start Tor", e);
                         if(e.getCause() instanceof TorControlError) {
-                            throw new IOException("Failed to start Tor", e.getCause());
+                            if(e.getCause().getMessage().contains("Failed to bind")) {
+                                throw new TorServerAlreadyBoundException("Tor server already bound", e.getCause());
+                            }
+                            log.error("Failed to start Tor", e);
+                            throw new TorServerException("Failed to start Tor", e.getCause());
                         } else {
-                            throw new IOException("Failed to start Tor", e);
+                            log.error("Failed to start Tor", e);
+                            throw new TorServerException("Failed to start Tor", e);
                         }
                     }
                 }

src/main/java/com/sparrowwallet/sparrow/preferences/ServerPreferencesController.java

@@ -306,7 +306,7 @@ public class ServerPreferencesController extends PreferencesDetailController {
             testConnection.setGraphic(getGlyph(FontAwesome5.Glyph.ELLIPSIS_H, null));
             testResults.setText("Connecting to " + config.getServerAddress() + "...");
 
-            if(Config.get().requiresTor() && Tor.getDefault() == null) {
+            if(Config.get().requiresInternalTor() && Tor.getDefault() == null) {
                 startTor();
             } else {
                 startElectrumConnection();
@@ -430,8 +430,10 @@ public class ServerPreferencesController extends PreferencesDetailController {
 
             Throwable exception = workerStateEvent.getSource().getException();
             if(Config.get().getServerType() == ServerType.ELECTRUM_SERVER &&
-                    exception.getCause() != null && exception.getCause() instanceof TorControlError && exception.getCause().getMessage().contains("Failed to bind") &&
+                    exception instanceof TorServerAlreadyBoundException &&
-                    useProxyOriginal == null && !useProxy.isSelected() && proxyHost.getText().isEmpty() && proxyPort.getText().isEmpty()) {
+                    useProxyOriginal == null && !useProxy.isSelected() &&
+                    (proxyHost.getText().isEmpty() || proxyHost.getText().equals("localhost") || proxyHost.getText().equals("127.0.0.1")) &&
+                    (proxyPort.getText().isEmpty() || proxyPort.getText().equals("9050"))) {
                 useProxy.setSelected(true);
                 proxyHost.setText("localhost");
                 proxyPort.setText("9050");
@@ -566,7 +568,9 @@ public class ServerPreferencesController extends PreferencesDetailController {
             }
 
             reason = tlsServerException.getMessage() + "\n\n" + reason;
-        } else if(exception.getCause() != null && exception.getCause() instanceof TorControlError && exception.getCause().getMessage().contains("Failed to bind")) {
+        } else if(exception instanceof ProxyServerException) {
+            reason += ". Check if the proxy server is running.";
+        } else if(exception instanceof TorServerAlreadyBoundException) {
             reason += "\nIs a Tor proxy already running on port " + TorService.PROXY_PORT + "?";
         }