add wallet export to electrum personal server config file

drongo

@@ -1 +1 @@
-Subproject commit aa459d0084b3cc72c49c8922d571338c4f5efaf4
+Subproject commit 311afd0409b7cb442e5ee1efebdc3c7dd628346a

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

@@ -42,9 +42,9 @@ public class WalletExportDialog extends Dialog<Wallet> {
 
         List<WalletExport> exporters;
         if(wallet.getPolicyType() == PolicyType.SINGLE) {
-            exporters = List.of(new Electrum(), new Descriptor(), new SpecterDesktop(), new Sparrow());
+            exporters = List.of(new Electrum(), new ElectrumPersonalServer(), new Descriptor(), new SpecterDesktop(), new Sparrow());
         } else if(wallet.getPolicyType() == PolicyType.MULTI) {
-            exporters = List.of(new CaravanMultisig(), new ColdcardMultisig(), new CoboVaultMultisig(), new Electrum(), new KeystoneMultisig(), new Descriptor(), new PassportMultisig(), new SpecterDesktop(), new BlueWalletMultisig(), new SpecterDIY(), new Sparrow());
+            exporters = List.of(new CaravanMultisig(), new ColdcardMultisig(), new CoboVaultMultisig(), new Electrum(), new ElectrumPersonalServer(), new KeystoneMultisig(), new Descriptor(), new PassportMultisig(), new SpecterDesktop(), new BlueWalletMultisig(), new SpecterDIY(), new Sparrow());
         } else {
             throw new UnsupportedOperationException("Cannot export wallet with policy type " + wallet.getPolicyType());
         }

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

@@ -0,0 +1,114 @@
+package com.sparrowwallet.sparrow.io;
+
+import com.sparrowwallet.drongo.ExtendedKey;
+import com.sparrowwallet.drongo.KeyPurpose;
+import com.sparrowwallet.drongo.policy.PolicyType;
+import com.sparrowwallet.drongo.protocol.ScriptType;
+import com.sparrowwallet.drongo.wallet.Keystore;
+import com.sparrowwallet.drongo.wallet.Wallet;
+import com.sparrowwallet.drongo.wallet.WalletModel;
+import com.sparrowwallet.drongo.wallet.WalletNode;
+
+import java.io.BufferedWriter;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.nio.charset.StandardCharsets;
+import java.util.Iterator;
+
+public class ElectrumPersonalServer implements WalletExport {
+    @Override
+    public String getName() {
+        return "Electrum Personal Server";
+    }
+
+    @Override
+    public WalletModel getWalletModel() {
+        return WalletModel.EPS;
+    }
+
+    @Override
+    public void exportWallet(Wallet wallet, OutputStream outputStream) throws ExportException {
+        if(wallet.getScriptType() == ScriptType.P2TR) {
+            throw new ExportException(getName() + " does not support Taproot wallets.");
+        }
+
+        try {
+            BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(outputStream, StandardCharsets.UTF_8));
+            writer.write("# Electrum Personal Server configuration file fragments\n");
+            writer.write("# Copy the lines below into the relevant sections in your EPS config.ini file\n\n");
+            writer.write("# Copy into [master-public-keys] section\n");
+            writer.write(wallet.getFullName().replace(' ', '_') + " = ");
+
+            ExtendedKey.Header xpubHeader = ExtendedKey.Header.fromScriptType(wallet.getScriptType(), false);
+            if(wallet.getPolicyType() == PolicyType.MULTI) {
+                writer.write(wallet.getDefaultPolicy().getNumSignaturesRequired() + " ");
+            }
+
+            for(Iterator<Keystore> iter = wallet.getKeystores().iterator(); iter.hasNext(); ) {
+                Keystore keystore = iter.next();
+                writer.write(keystore.getExtendedPublicKey().toString(xpubHeader));
+
+                if(iter.hasNext()) {
+                    writer.write(" ");
+                }
+            }
+
+            writer.newLine();
+
+            if(wallet.hasPaymentCode()) {
+                writer.write("\n# Copy into [watch-only-addresses] section\n");
+                WalletNode notificationNode = wallet.getNotificationWallet().getNode(KeyPurpose.NOTIFICATION);
+                writer.write(wallet.getFullName().replace(' ', '_') + "-notification_addr = " + notificationNode.getAddress().toString() + "\n");
+
+                for(Wallet childWallet : wallet.getChildWallets()) {
+                    if(childWallet.isBip47()) {
+                        writer.write(childWallet.getFullName().replace(' ', '_') + " = ");
+                        for(Iterator<KeyPurpose> purposeIterator = KeyPurpose.DEFAULT_PURPOSES.iterator(); purposeIterator.hasNext(); ) {
+                            KeyPurpose keyPurpose = purposeIterator.next();
+                            for(Iterator<WalletNode> iter = childWallet.getNode(keyPurpose).getChildren().iterator(); iter.hasNext(); ) {
+                                WalletNode receiveNode = iter.next();
+                                writer.write(receiveNode.getAddress().toString());
+
+                                if(iter.hasNext()) {
+                                   writer.write(" ");
+                                }
+                            }
+
+                            if(purposeIterator.hasNext()) {
+                                writer.write(" ");
+                            }
+                        }
+
+                        writer.newLine();
+                    }
+                }
+
+                writer.write("\n# Important: If this wallet receives any BIP47 payments, redo this export");
+            }
+
+            writer.flush();
+        } catch(Exception e) {
+            throw new ExportException("Could not export wallet", e);
+        }
+    }
+
+    @Override
+    public String getWalletExportDescription() {
+        return "Export this wallet as a configuration file fragment to copy into your Electrum Personal Server (EPS) config.ini file.";
+    }
+
+    @Override
+    public String getExportFileExtension(Wallet wallet) {
+        return "ini";
+    }
+
+    @Override
+    public boolean isWalletExportScannable() {
+        return false;
+    }
+
+    @Override
+    public boolean walletExportRequiresDecryption() {
+        return false;
+    }
+}

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

@@ -364,7 +364,7 @@ public class ElectrumServer {
     }
 
     private int getGapLimitSize(Wallet wallet, Map<WalletNode, Set<BlockTransactionHash>> nodeTransactionMap) {
-        int highestIndex = nodeTransactionMap.keySet().stream().map(WalletNode::getIndex).max(Comparator.comparing(Integer::valueOf)).orElse(-1);
+        int highestIndex = nodeTransactionMap.keySet().stream().filter(node -> node.getDerivation().size() > 1).map(WalletNode::getIndex).max(Comparator.comparing(Integer::valueOf)).orElse(-1);
         return highestIndex + wallet.getGapLimit() + 1;
     }