From 8d25f238496444ccc26ceb7ea5fa1b732219076b Mon Sep 17 00:00:00 2001
From: Ivan Socolsky <jungans@gmail.com>
Date: Fri, 19 Feb 2016 11:11:43 -0300
Subject: [PATCH] get send max info

---
 lib/model/txproposal.js |  8 ++++--
 lib/server.js           | 62 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+), 2 deletions(-)

diff --git a/lib/model/txproposal.js b/lib/model/txproposal.js
index 6f5d782..dfa98cd 100644
--- a/lib/model/txproposal.js
+++ b/lib/model/txproposal.js
@@ -252,10 +252,14 @@ TxProposal.prototype.getEstimatedSize = function() {
   return parseInt((size * (1 + safetyMargin)).toFixed(0));
 };
 
-TxProposal.prototype.estimateFee = function() {
+TxProposal.prototype.getEstimatedFee = function() {
   $.checkState(_.isNumber(this.feePerKb));
   var fee = this.feePerKb * this.getEstimatedSize() / 1000;
-  this.fee = parseInt(fee.toFixed(0));
+  return parseInt(fee.toFixed(0));
+};
+
+TxProposal.prototype.estimateFee = function() {
+  this.fee = this.getEstimatedFee();
 };
 
 /**
diff --git a/lib/server.js b/lib/server.js
index 1eefa57..f828faa 100644
--- a/lib/server.js
+++ b/lib/server.js
@@ -1148,6 +1148,68 @@ WalletService.prototype.getBalance = function(opts, cb) {
   });
 };
 
+/**
+ * Return info needed to send all funds in the wallet
+ * @param {Object} opts
+ * @param {string} opts.feePerKb - The fee per KB used to compute the TX.
+ * @param {string} opts.excludeUnconfirmedUtxos - Exclude unconfirmed UTXOs from calculation.
+ * @returns {Object} sendMaxInfo
+ */
+WalletService.prototype.getSendMaxInfo = function(opts, cb) {
+  var self = this;
+
+
+  opts = opts || {};
+
+  if (!Utils.checkRequired(opts, ['feePerKb', 'excludeUnconfirmedUtxos']))
+    return cb(new ClientError('Required argument missing'));
+
+  self.getWallet({}, function(err, wallet) {
+    if (err) return cb(err);
+
+    self._getUtxosForCurrentWallet(null, function(err, utxos) {
+      if (err) return cb(err);
+
+      var info = {
+        size: 0,
+        amount: 0,
+        fee: 0,
+        nbInputs: 0,
+      };
+
+      var inputs = _.reject(utxos, 'locked');
+      if (opts.excludeUnconfirmedUtxos) {
+        inputs = _.filter(inptus, 'confirmations');
+      }
+      inputs = _.sortBy(inputs, 'satoshis');
+
+      if (_.isEmpty(inputs)) return cb(null, info);
+
+      var txp = Model.TxProposal.create({
+        walletId: self.walletId,
+        network: wallet.network,
+        walletM: wallet.m,
+        walletN: wallet.n,
+        feePerKb: opts.feePerKb,
+      });
+
+      var lastFee = txp.getEstimatedFee();
+      _.eachRight(inputs, function(input) {
+        txp.inputs.push(input);
+        var fee = txp.getEstimatedFee();
+        if (fee - lastFee > input.satoshis) return false;
+        lastFee = fee;
+      });
+
+      info.size = txp.getEstimatedSize();
+      info.fee = txp.getEstimatedFee();
+      info.amount = _.sum(txp.inputs, 'satoshis') - info.fee;
+      info.nbInputs = txp.inputs.length;
+
+      return cb(null, info);
+    });
+  });
+};
 
 WalletService.prototype._sampleFeeLevels = function(network, points, cb) {
   var self = this;