wallet: optimize depth syncing.

lib/wallet/account.js

@@ -234,7 +234,8 @@ Account.prototype.init = co(function* init() {
   assert(this.nestedDepth === 0);
 
   this.initialized = true;
-  yield this.setDepth(1, 1, 1);
+
+  yield this.initDepth();
 });
 
 /**
@@ -433,32 +434,29 @@ Account.prototype.createNested = function createNested() {
  */
 
 Account.prototype.createKey = co(function* createKey(branch) {
-  var ring, lookahead;
+  var key, lookahead;
 
   switch (branch) {
     case 0:
-      ring = this.deriveReceive(this.receiveDepth);
+      key = this.deriveReceive(this.receiveDepth);
       lookahead = this.deriveReceive(this.receiveDepth + this.lookahead);
-      yield this.saveKey(ring);
       yield this.saveKey(lookahead);
       this.receiveDepth++;
-      this.receive = ring;
+      this.receive = key;
       break;
     case 1:
-      ring = this.deriveChange(this.changeDepth);
+      key = this.deriveChange(this.changeDepth);
       lookahead = this.deriveChange(this.changeDepth + this.lookahead);
-      yield this.saveKey(ring);
       yield this.saveKey(lookahead);
       this.changeDepth++;
-      this.change = ring;
+      this.change = key;
       break;
     case 2:
-      ring = this.deriveNested(this.nestedDepth);
+      key = this.deriveNested(this.nestedDepth);
       lookahead = this.deriveNested(this.nestedDepth + this.lookahead);
-      yield this.saveKey(ring);
       yield this.saveKey(lookahead);
       this.nestedDepth++;
-      this.nested = ring;
+      this.nested = key;
       break;
     default:
       throw new Error('Bad branch: ' + branch);
@@ -466,7 +464,7 @@ Account.prototype.createKey = co(function* createKey(branch) {
 
   this.save();
 
-  return ring;
+  return key;
 });
 
 /**
@@ -608,68 +606,121 @@ Account.prototype.savePath = function savePath(path) {
 };
 
 /**
- * Set change and receiving depth (depth is the index of the _next_ address).
- * Allocate all addresses up to depth. Note that this also allocates
- * new lookahead addresses.
- * @param {Number} depth
- * @returns {Promise} - Returns {@link WalletKey}, {@link WalletKey}.
+ * Initialize address depths (including lookahead).
+ * @returns {Promise}
  */
 
-Account.prototype.setDepth = co(function* setDepth(receiveDepth, changeDepth, nestedDepth) {
-  var i = -1;
-  var receive, change, nested, lookahead;
+Account.prototype.initDepth = co(function* initDepth() {
+  var i, key;
 
-  if (receiveDepth > this.receiveDepth) {
-    for (i = this.receiveDepth; i < receiveDepth; i++) {
-      receive = this.deriveReceive(i);
-      yield this.saveKey(receive);
-    }
+  // Receive Address
+  this.receive = this.deriveReceive(0);
+  this.receiveDepth = 1;
 
-    for (i = receiveDepth; i < receiveDepth + this.lookahead; i++) {
-      lookahead = this.deriveReceive(i);
-      yield this.saveKey(lookahead);
-    }
+  yield this.saveKey(this.receive);
 
-    this.receive = receive;
-    this.receiveDepth = receiveDepth;
+  // Change Address
+  this.change = this.deriveChange(0);
+  this.changeDepth = 1;
+
+  yield this.saveKey(this.change);
+
+  // Nested Address
+  if (this.witness) {
+    this.nested = this.deriveNested(0);
+    this.nestedDepth = 1;
+
+    yield this.saveKey(this.nested);
   }
 
-  if (changeDepth > this.changeDepth) {
-    for (i = this.changeDepth; i < changeDepth; i++) {
-      change = this.deriveChange(i);
-      yield this.saveKey(change);
-    }
-
-    for (i = changeDepth; i < changeDepth + this.lookahead; i++) {
-      lookahead = this.deriveChange(i);
-      yield this.saveKey(lookahead);
-    }
-
-    this.change = change;
-    this.changeDepth = changeDepth;
+  // Lookaheads
+  for (i = 0; i < this.lookahead; i++) {
+    key = this.deriveReceive(i + 1);
+    yield this.saveKey(key);
   }
 
-  if (this.witness && nestedDepth > this.nestedDepth) {
-    for (i = this.nestedDepth; i < nestedDepth; i++) {
-      nested = this.deriveNested(i);
-      yield this.saveKey(nested);
-    }
-
-    for (i = nestedDepth; i < nestedDepth + this.lookahead; i++) {
-      lookahead = this.deriveNested(i);
-      yield this.saveKey(lookahead);
-    }
-
-    this.nested = nested;
-    this.nestedDepth = nestedDepth;
+  for (i = 0; i < this.lookahead; i++) {
+    key = this.deriveChange(i + 1);
+    yield this.saveKey(key);
   }
 
-  if (i === -1)
-    return;
+  if (this.witness) {
+    for (i = 0; i < this.lookahead; i++) {
+      key = this.deriveNested(i + 1);
+      yield this.saveKey(key);
+    }
+  }
 
   this.save();
+});
 
-  return receive || nested;
+/**
+ * Allocate new lookahead addresses if necessary.
+ * @param {Number} receiveDepth
+ * @param {Number} changeDepth
+ * @param {Number} nestedDepth
+ * @returns {Promise} - Returns {@link WalletKey}.
+ */
+
+Account.prototype.syncDepth = co(function* syncDepth(receive, change, nested) {
+  var derived = false;
+  var result = null;
+  var i, depth, key;
+
+  if (receive > this.receiveDepth) {
+    depth = this.receiveDepth + this.lookahead;
+
+    assert(receive < depth);
+
+    for (i = depth; i < receive + this.lookahead; i++) {
+      key = this.deriveReceive(i);
+      yield this.saveKey(key);
+    }
+
+    this.receive = this.deriveReceive(receive - 1);
+    this.receiveDepth = receive;
+
+    derived = true;
+    result = this.receive;
+  }
+
+  if (change > this.changeDepth) {
+    depth = this.changeDepth + this.lookahead;
+
+    assert(change < depth);
+
+    for (i = depth; i < change + this.lookahead; i++) {
+      key = this.deriveChange(i);
+      yield this.saveKey(key);
+    }
+
+    this.change = this.deriveChange(change - 1);
+    this.changeDepth = change;
+
+    derived = true;
+  }
+
+  if (this.witness && nested > this.nestedDepth) {
+    depth = this.nestedDepth + this.lookahead;
+
+    assert(nested < depth);
+
+    for (i = depth; i < nested + this.lookahead; i++) {
+      key = this.deriveNested(i);
+      yield this.saveKey(key);
+    }
+
+    this.nested = this.deriveNested(nested - 1);
+    this.nestedDepth = nested;
+
+    derived = true;
+    result = this.nested;
+  }
+
+  if (derived)
+    this.save();
+
+  return result;
 });
 
 /**

lib/wallet/wallet.js

@@ -1659,7 +1659,7 @@ Wallet.prototype.getKey = co(function* getKey(address) {
 
 Wallet.prototype.getPrivateKey = co(function* getPrivateKey(address, passphrase) {
   var hash = Address.getHash(address, 'hex');
-  var path, account;
+  var path, account, key;
 
   if (!hash)
     return;
@@ -1676,7 +1676,12 @@ Wallet.prototype.getPrivateKey = co(function* getPrivateKey(address, passphrase)
 
   yield this.unlock(passphrase);
 
-  return account.derivePath(path, this.master);
+  key = account.derivePath(path, this.master);
+
+  if (!key.privateKey)
+    return;
+
+  return key;
 });
 
 /**
@@ -1796,7 +1801,7 @@ Wallet.prototype.syncOutputDepth = co(function* syncOutputDepth(details) {
     if (!account)
       continue;
 
-    ring = yield account.setDepth(receive, change, nested);
+    ring = yield account.syncDepth(receive, change, nested);
 
     if (ring)
       derived.push(ring);