From 47cb4c330c4456210e40d00bdbd0b962266d8b44 Mon Sep 17 00:00:00 2001
From: Stephen Pair <stephen@bitpay.com>
Date: Sun, 7 Jul 2013 14:46:59 -0400
Subject: [PATCH] add ability to get and set the hash of a BitcoinAddress

---
 BitcoinAddress.js | 24 +++++++++++++++++++-----
 1 file changed, 19 insertions(+), 5 deletions(-)

diff --git a/BitcoinAddress.js b/BitcoinAddress.js
index b016570..d15a014 100644
--- a/BitcoinAddress.js
+++ b/BitcoinAddress.js
@@ -8,18 +8,24 @@ function ClassSpec(b) {
     this.__proto__ = encodings[encoding || 'base58'];
   };
 
-  // return the bitcoin address version (the first byte of the address)
+  // get or set the bitcoin address version (the first byte of the address)
   BitcoinAddress.prototype.version = function(num) {
     if(num || (num === 0)) {
-      var oldEncoding = this.encoding();
-      this.encoding('binary');
-      this.data.writeUInt8(num, 0);
-      this.encoding(oldEncoding);
+      this.doAsBinary(function() {this.data.writeUInt8(num, 0);});
       return num;
     }
     return this.as('binary').readUInt8(0);
   };
 
+  // get or set the hash data (as a Buffer object)
+  BitcoinAddress.prototype.hash = function(data) {
+    if(data) {
+      this.doAsBinary(function() {data.copy(this.data,1);});
+      return data;
+    }
+    return this.as('binary').slice(1);
+  };
+
   // get or set the encoding used (transforms data)
   BitcoinAddress.prototype.encoding = function(encoding) {
     if(encoding && (encoding != this._encoding)) {
@@ -50,6 +56,14 @@ function ClassSpec(b) {
     return this.as('base58');
   };
 
+  // utility
+  BitcoinAddress.prototype.doAsBinary = function(callback) {
+    var oldEncoding = this.encoding();
+    this.encoding('binary');
+    callback.apply(this);
+    this.encoding(oldEncoding);
+  };
+
   // Setup support for various address encodings.  The object for
   // each encoding inherits from the BitcoinAddress prototype.  This
   // allows any encoding to override any method...changing the encoding