From a0d109f52d9a7e6383709662bad8a0264abdf036 Mon Sep 17 00:00:00 2001
From: Christopher Jeffrey <chjjeffrey@gmail.com>
Date: Wed, 10 Aug 2016 19:33:32 -0700
Subject: [PATCH] rpc: gettxoutproof and verifytxoutproof.

---
 lib/bcoin/http/rpc.js    | 106 +++++++++++++++++++++++++++++++++++++--
 lib/bcoin/merkleblock.js |  59 ++++++++++++++++++++--
 2 files changed, 157 insertions(+), 8 deletions(-)

diff --git a/lib/bcoin/http/rpc.js b/lib/bcoin/http/rpc.js
index fefff9a7..a1325e68 100644
--- a/lib/bcoin/http/rpc.js
+++ b/lib/bcoin/http/rpc.js
@@ -1157,11 +1157,108 @@ RPC.prototype.gettxout = function gettxout(args, callback) {
 };
 
 RPC.prototype.gettxoutproof = function gettxoutproof(args, callback) {
-  callback(new Error('Not implemented.'));
+  var self = this;
+  var uniq = {};
+  var i, txids, block, hash, last;
+
+  if (args.help || (args.length !== 1 && args.length !== 2)) {
+    return callback(new RPCError('gettxoutproof'
+      + ' ["txid",...] ( blockhash )'));
+  }
+
+  txids = args[0];
+  block = args[1];
+
+  if (!Array.isArray(txids) || txids.length === 0)
+    return callback(new RPCError('Invalid parameter.'));
+
+  if (block) {
+    if (!utils.isHex(block) || block.length !== 64)
+      return callback(new RPCError('Invalid parameter.'));
+    block = utils.revHex(block);
+  }
+
+  for (i = 0; i < txids.length; i++) {
+    hash = txids[i];
+    if (!utils.isHex(hash) || hash.length !== 64)
+      return callback(new RPCError('Invalid parameter.'));
+    hash = utils.revHex(hash);
+    if (uniq[hash])
+      return callback(new RPCError('Duplicate txid.'));
+    uniq[hash] = true;
+    txids[i] = hash;
+    last = hash;
+  }
+
+  function getBlock(callback) {
+    if (hash)
+      return self.chain.db.getBlock(hash, callback);
+
+    if (self.chain.options.indexTX) {
+      return self.chain.db.getTX(last, function(err, tx) {
+        if (err)
+          return callback(err);
+        if (!tx)
+          return callback();
+        self.chain.db.getBlock(tx.block, callback);
+      });
+    }
+
+    self.chain.db.getCoins(last, function(err, coins) {
+      if (err)
+        return callback(err);
+
+      if (!coins)
+        return callback();
+
+      self.chain.db.getBlock(coins.height, callback);
+    });
+  }
+
+  getBlock(function(err, block) {
+    if (err)
+      return callback(err);
+
+    if (!block)
+      return callback(new RPCError('Block not found.'));
+
+    for (i = 0; i < txids.length; i++) {
+      if (!block.hasTX(txids[i]))
+        return callback(new RPCError('Block does not contain all txids.'));
+    }
+
+    block = bcoin.merkleblock.fromHashes(block, txids);
+
+    callback(null, block.toRaw().toString('hex'));
+  });
 };
 
 RPC.prototype.verifytxoutproof = function verifytxoutproof(args, callback) {
-  callback(new Error('Not implemented.'));
+  var res = [];
+  var i, block, hash;
+
+  if (args.help || args.length !== 1)
+    return callback(new RPCError('verifytxoutproof "proof"'));
+
+  block = bcoin.merkleblock.fromRaw(String(args[0]), 'hex');
+
+  if (!block.verify())
+    return callback(null, res);
+
+  this.chain.db.get(block.hash('hex'), function(err, entry) {
+    if (err)
+      return callback(err);
+
+    if (!entry)
+      return callback(new RPCError('Block not found in chain.'));
+
+    for (i = 0; i < block.matches.length; i++) {
+      hash = block.matches[i];
+      res.push(utils.revHex(hash));
+    }
+
+    callback(null, res);
+  });
 };
 
 RPC.prototype.gettxoutsetinfo = function gettxoutsetinfo(args, callback) {
@@ -1446,6 +1543,9 @@ RPC.prototype.getnetworkhashps = function getnetworkhashps(args, callback) {
   lookup = args.length > 0 ? Number(args[0]) : 120;
   height = args.length > 1 ? Number(args[1]) : -1;
 
+  if (!utils.isNumber(lookup) || !utils.isNumber(height))
+    return callback(new RPCError('Invalid parameter.'));
+
   return this._hashps(lookup, height, callback);
 };
 
@@ -1461,7 +1561,7 @@ RPC.prototype.submitblock = function submitblock(args, callback) {
       + ' ( "jsonparametersobject" )'));
   }
 
-  block = bcoin.block.fromRaw(args[0], 'hex');
+  block = bcoin.block.fromRaw(String(args[0]), 'hex');
 
   this.chain.add(block, function(err, total) {
     if (err)
diff --git a/lib/bcoin/merkleblock.js b/lib/bcoin/merkleblock.js
index 8720a201..85d17624 100644
--- a/lib/bcoin/merkleblock.js
+++ b/lib/bcoin/merkleblock.js
@@ -448,6 +448,59 @@ MerkleBlock.fromJSON = function fromJSON(json) {
 
 MerkleBlock.fromBlock = function fromBlock(block, filter) {
   var matches = [];
+  var i, tx;
+
+  for (i = 0; i < block.txs.length; i++) {
+    tx = block.txs[i];
+    if (tx.isWatched(filter))
+      matches.push(1);
+    else
+      matches.push(0);
+  }
+
+  return MerkleBlock.fromMatches(block, matches);
+};
+
+/**
+ * Create a merkleblock from an array of txids.
+ * This will build the partial merkle tree.
+ * @param {Block} block
+ * @param {Hash[]} hashes
+ * @returns {MerkleBlock}
+ */
+
+MerkleBlock.fromHashes = function fromHashes(block, hashes) {
+  var filter = {};
+  var matches = [];
+  var i, tx, hash;
+
+  for (i = 0; i < hashes.length; i++) {
+    hash = hashes[i];
+    if (Buffer.isBuffer(hash))
+      hash = hash.toString('hex');
+    filter[hash] = true;
+  }
+
+  for (i = 0; i < block.txs.length; i++) {
+    tx = block.txs[i];
+    if (filter[tx.hash('hex')])
+      matches.push(1);
+    else
+      matches.push(0);
+  }
+
+  return MerkleBlock.fromMatches(block, matches);
+};
+
+/**
+ * Create a merkleblock from an array of matches.
+ * This will build the partial merkle tree.
+ * @param {Block} block
+ * @param {Number[]} matches
+ * @returns {MerkleBlock}
+ */
+
+MerkleBlock.fromMatches = function fromMatches(block, matches) {
   var txs = [];
   var leaves = [];
   var bits = [];
@@ -456,12 +509,8 @@ MerkleBlock.fromBlock = function fromBlock(block, filter) {
 
   for (i = 0; i < block.txs.length; i++) {
     tx = block.txs[i];
-    if (tx.isWatched(filter)) {
-      matches.push(1);
+    if (matches[i])
       txs.push(tx);
-    } else {
-      matches.push(0);
-    }
     leaves.push(tx.hash());
   }