Another rework of null seed wallets, to allow them to be saved and loaded.

A full sync is unavoidable for P2SH redeem/refund, so we need to be able to save our progress. Creating a new null seed wallet each time isn't an option because it relies on having a recent checkpoint to avoid having to sync large amounts of blocks every time (sync is per wallet, not per node).

src/main/java/org/qortal/controller/PirateChainWalletController.java

@@ -87,7 +87,15 @@ public class PirateChainWalletController extends Thread {
     }
 
 
-    public boolean initWithEntropy58(String entropy58) throws ForeignBlockchainException {
+    public boolean initWithEntropy58(String entropy58) {
+        return this.initWithEntropy58(entropy58, false);
+    }
+
+    public boolean initNullSeedWallet() {
+        return this.initWithEntropy58(Base58.encode(new byte[32]), true);
+    }
+
+    private boolean initWithEntropy58(String entropy58, boolean isNullSeedWallet) {
         byte[] entropyBytes = Base58.decode(entropy58);
 
         if (entropyBytes == null || entropyBytes.length != 32) {
@@ -107,9 +115,9 @@ public class PirateChainWalletController extends Thread {
         }
 
         try {
-            this.currentWallet = new PirateWallet(entropyBytes, false);
-            if (!this.currentWallet.isReady() || this.currentWallet.hasNullSeed()) {
-                // Don't persist wallets that aren't ready or are null seed
+            this.currentWallet = new PirateWallet(entropyBytes, isNullSeedWallet);
+            if (!this.currentWallet.isReady()) {
+                // Don't persist wallets that aren't ready
                 this.currentWallet = null;
             }
             return true;
@@ -120,16 +128,6 @@ public class PirateChainWalletController extends Thread {
         return false;
     }
 
-    public PirateWallet switchToNullWallet() {
-        try {
-            this.currentWallet = null;
-            return new PirateWallet(null, true);
-
-        } catch (IOException e) {
-            return null;
-        }
-    }
-
     private void saveCurrentWallet() {
         if (this.currentWallet == null) {
             // Nothing to do
@@ -164,7 +162,7 @@ public class PirateChainWalletController extends Thread {
 
     public void ensureNotNullSeed() throws ForeignBlockchainException {
         // Safety check to make sure funds aren't sent to a null seed wallet
-        if (this.currentWallet == null || this.currentWallet.hasNullSeed()) {
+        if (this.currentWallet == null || this.currentWallet.isNullSeedWallet()) {
             throw new ForeignBlockchainException("Invalid wallet");
         }
     }

src/main/java/org/qortal/crosschain/PirateChain.java

@@ -434,10 +434,13 @@ public class PirateChain extends Bitcoiny {
 	public String redeemP2sh(String p2shAddress, String receivingAddress, long amount, String redeemScript58,
 							 String fundingTxid58, String secret58, String privateKey58) throws ForeignBlockchainException {
 
-		PirateWallet wallet = PirateChainWalletController.getInstance().switchToNullWallet();
-		if (wallet == null) {
-			throw new ForeignBlockchainException("Unable to initialize null seed Pirate Chain wallet");
-		}
+		// Use null seed wallet since we may not have the entropy bytes for a real wallet's seed
+		PirateChainWalletController walletController = PirateChainWalletController.getInstance();
+		walletController.initNullSeedWallet();
+		walletController.ensureInitialized();
+		walletController.ensureSynchronized();
+
+		walletController.getCurrentWallet().unlock();
 
 		// Build spend
 		JSONObject txn = new JSONObject();
@@ -483,10 +486,13 @@ public class PirateChain extends Bitcoiny {
 	public String refundP2sh(String p2shAddress, String receivingAddress, long amount, String redeemScript58,
 							 String fundingTxid58, int lockTime, String privateKey58) throws ForeignBlockchainException {
 
-		PirateWallet wallet = PirateChainWalletController.getInstance().switchToNullWallet();
-		if (wallet == null) {
-			throw new ForeignBlockchainException("Unable to initialize null seed Pirate Chain wallet");
-		}
+		// Use null seed wallet since we may not have the entropy bytes for a real wallet's seed
+		PirateChainWalletController walletController = PirateChainWalletController.getInstance();
+		walletController.initNullSeedWallet();
+		walletController.ensureInitialized();
+		walletController.ensureSynchronized();
+
+		walletController.getCurrentWallet().unlock();
 
 		// Build spend
 		JSONObject txn = new JSONObject();

src/main/java/org/qortal/crosschain/PirateWallet.java

@@ -65,14 +65,7 @@ public class PirateWallet {
             LiteWalletJni.initlogging();
 
             if (this.entropyBytes == null) {
-                if (this.isNullSeedWallet) {
-                    // Use null seed
-                    this.entropyBytes = new byte[32];
-                }
-                else {
-                    // Need entropy bytes for a non-null seed wallet
-                    return false;
-                }
+                return false;
             }
 
             // Pirate library uses base64 encoding
@@ -93,7 +86,7 @@ public class PirateWallet {
                 int birthday = DEFAULT_BIRTHDAY;
                 if (this.isNullSeedWallet) {
                     try {
-                        // Attempt to set birthday to the current block for null wallets
+                        // Attempt to set birthday to the current block for null seed wallets
                         birthday = PirateChain.getInstance().blockchainProvider.getCurrentHeight();
                     }
                     catch (ForeignBlockchainException e) {
@@ -197,10 +190,6 @@ public class PirateWallet {
             LOGGER.info("Error: can't save wallet, because no wallet it initialized");
             return false;
         }
-        if (this.isNullSeedWallet) {
-            LOGGER.info("Error: can't save null wallet");
-            return false;
-        }
 
         // Encrypt first (will do nothing if already encrypted)
         this.encrypt();
@@ -229,10 +218,6 @@ public class PirateWallet {
     }
 
     public String load() throws IOException {
-        if (this.isNullSeedWallet) {
-            // Can't load null seed wallets
-            return null;
-        }
         Path walletPath = this.getCurrentWalletPath();
         if (!Files.exists(walletPath)) {
             return null;
@@ -321,7 +306,7 @@ public class PirateWallet {
         return null;
     }
 
-    public boolean hasNullSeed() {
+    public boolean isNullSeedWallet() {
         return this.isNullSeedWallet;
     }