From 0f23304a6872d088a3d7f0c3821aee2953f54385 Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Thu, 18 Aug 2016 20:29:30 -0700
Subject: [PATCH] mtx: maxSize.

---
 lib/bcoin/mtx.js    | 61 ++++++++++++++++++++-------------------------
 lib/bcoin/wallet.js |  5 ++--
 2 files changed, 30 insertions(+), 36 deletions(-)

diff --git a/lib/bcoin/mtx.js b/lib/bcoin/mtx.js
index 03746e7e..04e7d128 100644
--- a/lib/bcoin/mtx.js
+++ b/lib/bcoin/mtx.js
@@ -925,49 +925,20 @@ MTX.prototype.isScripted = function isScripted() {
  * @param {(Wallet|Object)?} options - Wallet or options object.
  * @param {Number} options.m - Multisig `m` value.
  * @param {Number} options.n - Multisig `n` value.
- * @param {Boolean} force - `maxSize` will just calculate
- * the virtual size instead of _estimating_ it if the
- * templates are already built. If true, this will force
- * estimation of the size.
  * @returns {Number}
  */
 
-MTX.prototype.maxSize = function maxSize(options, force) {
+MTX.prototype.maxSize = function maxSize(options) {
   var scale = constants.WITNESS_SCALE_FACTOR;
   var i, j, input, total, size, prev, m, n, sz;
   var witness, hadWitness, redeem, wallet;
 
-  if (!force && this.isScripted())
+  if (!options && this.isScripted())
     return this.getVirtualSize();
 
   if (!options)
     options = {};
 
-  if (options instanceof bcoin.wallet)
-    options = { wallet: options };
-
-  if (options.wallet)
-    wallet = options.wallet;
-
-  function getRedeem(vector, hash) {
-    var redeem = vector.getRedeem();
-    var address;
-
-    if (redeem)
-      return redeem;
-
-    if (!wallet)
-      return;
-
-    // Hack
-    address = wallet.receiveAddress;
-
-    if (address.program && hash.length === 20)
-      return address.program;
-
-    return address.script;
-  }
-
   // Calculate the size, minus the input scripts.
   total = this.getBaseSize();
 
@@ -1001,7 +972,7 @@ MTX.prototype.maxSize = function maxSize(options, force) {
       // here since it will be ignored by
       // the isMultisig clause.
       // OP_PUSHDATA2 [redeem]
-      redeem = getRedeem(input.script, prev.get(1));
+      redeem = this._guessRedeem(prev.get(1), options);
       if (redeem) {
         prev = redeem;
         sz = prev.getSize();
@@ -1032,7 +1003,7 @@ MTX.prototype.maxSize = function maxSize(options, force) {
       hadWitness = true;
 
       if (prev.isWitnessScripthash()) {
-        redeem = getRedeem(input.witness, prev.get(1));
+        redeem = this._guessRedeem(prev.get(1), options);
         if (redeem) {
           prev = redeem;
           sz = prev.getSize();
@@ -1114,6 +1085,28 @@ MTX.prototype.maxSize = function maxSize(options, force) {
   return total;
 };
 
+/**
+ * "Guess" a redeem script based on some options.
+ * @private
+ * @param {Object} options
+ * @param {Buffer} hash
+ * @returns {Script|null}
+ */
+
+MTX.prototype._guessRedeem = function guessRedeem(options, hash) {
+  switch (hash.length) {
+    case 20:
+      if (options.witness) {
+        if (options.n > 1)
+          return bcoin.script.fromProgram(0, constants.ZERO_HASH);
+        return bcoin.script.fromProgram(0, constants.ZERO_HASH160);
+      }
+      return options.script;
+    case 32:
+      return options.script;
+  }
+};
+
 /**
  * Select necessary coins based on total output value.
  * @param {Coin[]} coins
@@ -1232,7 +1225,7 @@ MTX.prototype.selectCoins = function selectCoins(coins, options) {
     // bytes (10000 satoshi for every 1024 bytes).
     do {
       // Calculate max possible size after signing.
-      size = tx.maxSize(options, true);
+      size = tx.maxSize(options.key, options.script);
 
       if (tryFree && options.height >= 0) {
         // Note that this will only work
diff --git a/lib/bcoin/wallet.js b/lib/bcoin/wallet.js
index dc3f2225..8c96d9ac 100644
--- a/lib/bcoin/wallet.js
+++ b/lib/bcoin/wallet.js
@@ -878,9 +878,10 @@ Wallet.prototype.fund = function fund(tx, options, callback, force) {
           changeAddress: account.changeAddress.getAddress(),
           height: self.db.height,
           rate: rate,
-          wallet: self,
           m: account.m,
-          n: account.n
+          n: account.n,
+          witness: account.witness,
+          script: account.receiveAddress.script
         });
       } catch (e) {
         return callback(e);