From cf9a62a75baa360c18fb7f79792af1833c960342 Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Wed, 23 Mar 2016 16:15:36 -0700
Subject: [PATCH] coins and coinview.

---
 lib/bcoin.js          |   2 +
 lib/bcoin/block.js    |  15 ++++
 lib/bcoin/coins.js    | 197 ++++++++++++++++++++++++++++++++++++++++++
 lib/bcoin/coinview.js | 104 ++++++++++++++++++++++
 lib/bcoin/tx.js       |  17 ++++
 5 files changed, 335 insertions(+)
 create mode 100644 lib/bcoin/coins.js
 create mode 100644 lib/bcoin/coinview.js

diff --git a/lib/bcoin.js b/lib/bcoin.js
index 548ed0de..60751c93 100644
--- a/lib/bcoin.js
+++ b/lib/bcoin.js
@@ -95,6 +95,8 @@ bcoin.script = require('./bcoin/script');
 bcoin.input = require('./bcoin/input');
 bcoin.output = require('./bcoin/output');
 bcoin.coin = require('./bcoin/coin');
+bcoin.coins = require('./bcoin/coins');
+bcoin.coinview = require('./bcoin/coinview');
 bcoin.tx = require('./bcoin/tx');
 bcoin.mtx = require('./bcoin/mtx');
 bcoin.ldb = require('./bcoin/ldb');
diff --git a/lib/bcoin/block.js b/lib/bcoin/block.js
index 3339d207..24ce2570 100644
--- a/lib/bcoin/block.js
+++ b/lib/bcoin/block.js
@@ -271,6 +271,21 @@ Block.reward = function reward(height) {
   return reward;
 };
 
+Block.prototype.getPrevout = function getPrevout() {
+  var prevout = {};
+
+  this.txs.forEach(function(tx) {
+    if (tx.isCoinbase())
+      return;
+
+    tx.inputs.forEach(function(input) {
+      prevout[input.prevout.hash] = true;
+    });
+  });
+
+  return Object.keys(prevout);
+};
+
 Block.prototype.inspect = function inspect() {
   return {
     type: this.type,
diff --git a/lib/bcoin/coins.js b/lib/bcoin/coins.js
new file mode 100644
index 00000000..f9d26cc7
--- /dev/null
+++ b/lib/bcoin/coins.js
@@ -0,0 +1,197 @@
+/**
+ * coins.js - coins object for bcoin
+ * Copyright (c) 2014-2015, Fedor Indutny (MIT License)
+ * https://github.com/indutny/bcoin
+ */
+
+var bcoin = require('../bcoin');
+var utils = bcoin.utils;
+var assert = utils.assert;
+var constants = bcoin.protocol.constants;
+var BufferReader = require('./reader');
+var BufferWriter = require('./writer');
+
+/**
+ * Coins
+ */
+
+function Coins(options, hash) {
+  if (!(this instanceof Coins))
+    return new Coins(options, hash);
+
+  if (Buffer.isBuffer(hash))
+    hash = utils.toHex(hash);
+
+  this.version = options.version;
+  this.height = options.height;
+
+  this.coinbase = options.isCoinbase
+    ? options.isCoinbase()
+    : options.coinbase;
+
+  this.hash = hash;
+
+  this.outputs = options.outputs.map(function(coin, i) {
+    if (!coin)
+      return null;
+
+    if (coin instanceof bcoin.coin)
+      return coin;
+
+    coin = utils.merge({}, coin);
+    coin.version = options.version;
+    coin.height = options.height;
+    coin.hash = hash;
+    coin.index = i;
+    coin.coinbase = this.coinbase;
+
+    return new bcoin.coin(coin);
+  }, this);
+}
+
+Coins.prototype.add = function add(tx, i) {
+  var coin;
+
+  if (i == null) {
+    coin = tx;
+    this.outputs[coin.index] = coin;
+    return;
+  }
+
+  this.outputs[i] = new bcoin.coin(tx, i);
+};
+
+Coins.prototype.has = function has(index) {
+  return this.outputs[index] != null;
+};
+
+Coins.prototype.get = function get(index) {
+  return this.outputs[index];
+};
+
+Coins.prototype.remove = function remove(index) {
+  if (index < this.outputs.length)
+    this.outputs[index] = null;
+};
+
+Coins.prototype.spend = function spend(hash, index) {
+  var coin = this.get(hash, index);
+  this.remove(hash, index);
+  return coin;
+};
+
+Coins.prototype.fill = function fill(tx, spend) {
+  var res = true;
+  var i, input;
+
+  if (tx.txs)
+    tx = tx.txs;
+
+  if (Array.isArray(tx)) {
+    for (i = 0; i < tx.length; i++) {
+      if (!this.fill(tx[i]))
+        res = false;
+    }
+    return res;
+  }
+
+  for (i = 0; i < tx.inputs.length; i++) {
+    input = tx.inputs[i];
+
+    if (input.prevout.hash !== this.hash)
+      continue;
+
+    if (!input.output) {
+      if (spend)
+        input.output = this.spend(input.prevout.index);
+      else
+        input.output = this.get(input.prevout.index);
+
+      if (!input.output)
+        res = false;
+    }
+  }
+
+  return res;
+};
+
+Coins.prototype.count = function count(index) {
+  return this.outputs.reduce(function(total, output) {
+    if (!output)
+      return total;
+    return total + 1;
+  }, 0);
+};
+
+Coins.prototype.forEach = function forEach(callback, context) {
+  this.outputs.forEach(function(output, i) {
+    callback.call(context || this, output, i);
+  }, this);
+};
+
+Coins.prototype.toRaw = function toRaw() {
+  return Coins.toRaw(this);
+};
+
+Coins.fromTX = function fromTX(tx) {
+  return new Coins(tx, tx.hash('hex'));
+};
+
+Coins.toRaw = function toRaw(tx) {
+  var p = new BufferWriter();
+  var height = tx.height;
+
+  if (height === -1)
+    height = 0x7fffffff;
+
+  p.writeU32(tx.version);
+  p.writeU32(height);
+  p.writeU8(tx.coinbase ? 1 : 0);
+  p.writeUIntv(tx.outputs.length);
+
+  tx.outputs.forEach(function(output) {
+    if (!output) {
+      p.writeUIntv(0);
+      return;
+    }
+    p.writeVarBytes(bcoin.protocol.framer.output(output));
+  });
+
+  return p.render();
+};
+
+Coins._fromRaw = function _fromRaw(buf) {
+  var tx = { outputs: [] };
+  var p = new BufferReader(buf);
+  var coinCount, i, coin;
+
+  tx.version = p.readU32();
+  tx.height = p.readU32();
+  tx.coinbase = p.readU8() === 1;
+
+  if (tx.height === 0x7fffffff)
+    tx.height = -1;
+
+  coinCount = p.readUIntv();
+  for (i = 0; i < coinCount; i++) {
+    coin = p.readVarBytes();
+    if (coin.length === 0) {
+      tx.outputs.push(null);
+      continue;
+    }
+    coin = bcoin.protocol.parser.parseOutput(coin);
+    tx.outputs.push(coin);
+  }
+
+  return tx;
+};
+
+Coins.fromRaw = function fromRaw(buf, hash) {
+  return new Coins(Coins._fromRaw(buf), hash);
+};
+
+/**
+ * Expose
+ */
+
+module.exports = Coins;
diff --git a/lib/bcoin/coinview.js b/lib/bcoin/coinview.js
new file mode 100644
index 00000000..848645cd
--- /dev/null
+++ b/lib/bcoin/coinview.js
@@ -0,0 +1,104 @@
+/**
+ * coinview.js - coinview object for bcoin
+ * Copyright (c) 2014-2015, Fedor Indutny (MIT License)
+ * https://github.com/indutny/bcoin
+ */
+
+var bcoin = require('../bcoin');
+var utils = bcoin.utils;
+var assert = utils.assert;
+var constants = bcoin.protocol.constants;
+
+/**
+ * CoinView
+ */
+
+function CoinView(coins) {
+  if (!(this instanceof CoinView))
+    return new CoinView(coins);
+
+  this.coins = coins || {};
+}
+
+CoinView.prototype.add = function add(tx, i) {
+  var coin, hash;
+
+  if (i == null) {
+    coin = tx;
+    this.coins[coin.hash] = coin;
+    return;
+  }
+
+  hash = tx.hash('hex');
+
+  if (!this.coins[hash]) {
+    this.coins[hash] = Object.create(bcoin.coins.prototype);
+    this.coins[hash].version = tx.version;
+    this.coins[hash].height = tx.height;
+    this.coins[hash].coinbase = tx.isCoinbase();
+    this.coins[hash].hash = hash;
+    this.coins[hash].outputs = new Array(tx.outputs.length);
+  }
+
+  this.coins[hash].add(tx, i);
+};
+
+CoinView.prototype.get = function get(hash, index) {
+  if (!this.coins[hash])
+    return;
+
+  return this.coins[hash].get(index);
+};
+
+CoinView.prototype.count = function count(hash) {
+  if (!this.coins[hash])
+    return 0;
+
+  return this.coins[hash].count();
+};
+
+CoinView.prototype.has = function has(hash, index) {
+  if (!this.coins[hash])
+    return;
+
+  return this.coins[hash].has(index);
+};
+
+CoinView.prototype.remove = function remove(hash, index) {
+  if (!this.coins[hash])
+    return;
+
+  return this.coins[hash].remove(index);
+};
+
+CoinView.prototype.spend = function spend(hash, index) {
+  if (!this.coins[hash])
+    return;
+
+  return this.coins[hash].spend(index);
+};
+
+CoinView.prototype.fill = function fill(obj, spend) {
+  var keys = Object.keys(this.coins);
+  var res = true;
+  var i;
+
+  for (i = 0; i < keys.length; i++) {
+    if (!this.coins[keys[i]].fill(obj, spend))
+      res = false;
+  }
+
+  return res;
+};
+
+CoinView.prototype.toArray = function toArray() {
+  return Object.keys(this.coins).map(function(hash) {
+    return this.coins[hash];
+  }, this);
+};
+
+/**
+ * Expose
+ */
+
+module.exports = CoinView;
diff --git a/lib/bcoin/tx.js b/lib/bcoin/tx.js
index 4cd6600c..cfc4a640 100644
--- a/lib/bcoin/tx.js
+++ b/lib/bcoin/tx.js
@@ -1065,6 +1065,19 @@ TX.prototype.__defineGetter__('priority', function() {
   return this.getPriority();
 });
 
+TX.prototype.getPrevout = function getPrevout() {
+  var prevout = {};
+
+  if (this.isCoinbase())
+    return [];
+
+  this.inputs.forEach(function(input) {
+    prevout[input.prevout.hash] = true;
+  });
+
+  return Object.keys(prevout);
+};
+
 TX.prototype.inspect = function inspect() {
   return {
     type: this.type,
@@ -1242,6 +1255,10 @@ TX.fromExtended = function fromExtended(buf, saveCoins) {
   return new TX(TX._fromExtended(buf, saveCoins));
 };
 
+TX.prototype.toCoins = function toCoins() {
+  return bcoin.coins.fromTX(this);
+};
+
 /**
  * Expose
  */