From 0d180810defd2fc0b63ec21cb7e307c42a5ae949 Mon Sep 17 00:00:00 2001
From: "Ryan X. Charles" <ryan@bitpay.com>
Date: Tue, 16 Sep 2014 17:28:00 -0700
Subject: [PATCH] Blockheader

---
 lib/blockheader.js  | 62 ++++++++++++++++++++++++++++++++
 test/blockheader.js | 88 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 150 insertions(+)
 create mode 100644 lib/blockheader.js
 create mode 100644 test/blockheader.js

diff --git a/lib/blockheader.js b/lib/blockheader.js
new file mode 100644
index 000000000..cc17ea600
--- /dev/null
+++ b/lib/blockheader.js
@@ -0,0 +1,62 @@
+var BufferReader = require('./bufferreader');
+var BufferWriter = require('./bufferwriter');
+
+var Blockheader = function Blockheader(version, prevblockidbuf, merklerootbuf, time, bits, nonce) {
+  if (!(this instanceof Blockheader))
+    return new Blockheader(version, prevblockidbuf, merklerootbuf, time, bits, nonce);
+  if (typeof version === 'number') {
+    this.set({
+      version: version,
+      prevblockidbuf: prevblockidbuf,
+      merklerootbuf: merklerootbuf,
+      time: time,
+      bits: bits,
+      nonce: nonce
+    });
+  } else if (version) {
+    var obj = version;
+    this.set(obj);
+  }
+}
+
+Blockheader.prototype.set = function(obj) {
+  this.version = typeof obj.version !== 'undefined' ? obj.version : this.version;
+  this.prevblockidbuf = obj.prevblockidbuf || this.prevblockidbuf;
+  this.merklerootbuf = obj.merklerootbuf || this.merklerootbuf;
+  this.time = typeof obj.time !== 'undefined' ? obj.time : this.time;
+  this.bits = typeof obj.bits !== 'undefined' ? obj.bits : this.bits;
+  this.nonce = typeof obj.nonce !== 'undefined' ? obj.nonce : this.nonce;
+  return this;
+};
+
+Blockheader.prototype.fromBuffer = function(buf) {
+  return this.fromBufferReader(BufferReader(buf));
+};
+
+Blockheader.prototype.fromBufferReader = function(br) {
+  this.version = br.readUInt32LE();
+  this.prevblockidbuf = br.buffer(32);
+  this.merklerootbuf = br.buffer(32);
+  this.time = br.readUInt32LE();
+  this.bits = br.readUInt32LE();
+  this.nonce = br.readUInt32LE();
+  return this;
+};
+
+Blockheader.prototype.toBuffer = function() {
+  return this.toBufferWriter().concat();
+};
+
+Blockheader.prototype.toBufferWriter = function(bw) {
+  if (!bw)
+    bw = new BufferWriter();
+  bw.writeUInt32LE(this.version);
+  bw.write(this.prevblockidbuf);
+  bw.write(this.merklerootbuf);
+  bw.writeUInt32LE(this.time);
+  bw.writeUInt32LE(this.bits);
+  bw.writeUInt32LE(this.nonce);
+  return bw;
+};
+
+module.exports = Blockheader;
diff --git a/test/blockheader.js b/test/blockheader.js
new file mode 100644
index 000000000..03a335f30
--- /dev/null
+++ b/test/blockheader.js
@@ -0,0 +1,88 @@
+var Blockheader = require('../lib/blockheader');
+var BufferWriter = require('../lib/bufferwriter');
+var BufferReader = require('../lib/bufferreader');
+var should = require('chai').should();
+
+describe('Blockheader', function() {
+  
+  it('should make a new blockheader', function() {
+    var blockheader = new Blockheader();
+    should.exist(blockheader);
+    blockheader = Blockheader();
+    should.exist(blockheader);
+  });
+
+  var bh = new Blockheader();
+  var version = 1;
+  var prevblockidbuf = new Buffer(32);
+  prevblockidbuf.fill(5);
+  var merklerootbuf = new Buffer(32);
+  merklerootbuf.fill(9);
+  var time = 2;
+  var bits = 3;
+  var nonce = 4;
+  bh.set({
+    version: version,
+    prevblockidbuf: prevblockidbuf,
+    merklerootbuf: merklerootbuf,
+    time: time,
+    bits: bits,
+    nonce: nonce
+  });
+  bhhex = '0100000005050505050505050505050505050505050505050505050505050505050505050909090909090909090909090909090909090909090909090909090909090909020000000300000004000000';
+  bhbuf = new Buffer(bhhex, 'hex');
+
+  describe('#set', function() {
+
+    it('should set all the variables', function() {
+      bh.set({
+        version: version,
+        prevblockidbuf: prevblockidbuf,
+        merklerootbuf: merklerootbuf,
+        time: time,
+        bits: bits,
+        nonce: nonce
+      });
+      should.exist(bh.version);
+      should.exist(bh.prevblockidbuf);
+      should.exist(bh.merklerootbuf);
+      should.exist(bh.time);
+      should.exist(bh.bits);
+      should.exist(bh.nonce);
+    });
+
+  });
+
+  describe('#fromBuffer', function() {
+
+    it('should parse this known buffer', function() {
+      Blockheader().fromBuffer(bhbuf).toBuffer().toString('hex').should.equal(bhhex);
+    });
+
+  });
+
+  describe('#fromBufferReader', function() {
+
+    it('should parse this known buffer', function() {
+      Blockheader().fromBufferReader(BufferReader(bhbuf)).toBuffer().toString('hex').should.equal(bhhex);
+    });
+
+  });
+
+  describe('#toBuffer', function() {
+
+    it('should output this known buffer', function() {
+      Blockheader().fromBuffer(bhbuf).toBuffer().toString('hex').should.equal(bhhex);
+    });
+
+  });
+
+  describe('#toBufferWriter', function() {
+
+    it('should output this known buffer', function() {
+      Blockheader().fromBuffer(bhbuf).toBufferWriter().concat().toString('hex').should.equal(bhhex);
+    });
+
+  });
+
+});