From 53f6a31e7378fe7b0d401c1020cf428d53a64f46 Mon Sep 17 00:00:00 2001
From: Manuel Araoz <manuelaraoz@gmail.com>
Date: Thu, 11 Dec 2014 14:54:47 -0300
Subject: [PATCH] refactor script

---
 lib/script.js | 40 +++++++++++++++++++---------------------
 1 file changed, 19 insertions(+), 21 deletions(-)

diff --git a/lib/script.js b/lib/script.js
index 00e077af6..14f4ed8b3 100644
--- a/lib/script.js
+++ b/lib/script.js
@@ -202,13 +202,11 @@ Script.prototype.toString = function() {
  * @returns true if this is a pay to pubkey hash output script
  */
 Script.prototype.isPublicKeyHashOut = function() {
-  return !!(this.chunks[0] && this.chunks[0].opcodenum === Opcode.OP_DUP &&
-    this.chunks[1] &&
+  return !!(this.chunks.length === 5 &&
+    this.chunks[0].opcodenum === Opcode.OP_DUP &&
     this.chunks[1].opcodenum === Opcode.OP_HASH160 &&
     this.chunks[2].buf &&
-    this.chunks[3] &&
     this.chunks[3].opcodenum === Opcode.OP_EQUALVERIFY &&
-    this.chunks[4] &&
     this.chunks[4].opcodenum === Opcode.OP_CHECKSIG);
 };
 
@@ -216,12 +214,11 @@ Script.prototype.isPublicKeyHashOut = function() {
  * @returns true if this is a pay to public key hash input script
  */
 Script.prototype.isPublicKeyHashIn = function() {
-  return !!(this.chunks.length === 2 &&
+  return this.chunks.length === 2 &&
     this.chunks[0].buf &&
     this.chunks[0].buf.length >= 0x47 &&
     this.chunks[0].buf.length <= 0x49 &&
-    this.chunks[1].buf &&
-    PublicKey.isValid(this.chunks[1].buf));
+    PublicKey.isValid(this.chunks[1].buf);
 };
 
 /**
@@ -231,7 +228,7 @@ Script.prototype.isPublicKeyOut = function() {
   return this.chunks.length === 2 &&
     bufferUtil.isBuffer(this.chunks[0].buf) &&
     PublicKey.isValid(this.chunks[0].buf) &&
-    this.chunks[1] === Opcode('OP_CHECKSIG').toNumber();
+    this.chunks[1].opcodenum === Opcode('OP_CHECKSIG').toNumber();
 };
 
 /**
@@ -249,10 +246,10 @@ Script.prototype.isPublicKeyIn = function() {
  */
 Script.prototype.isScriptHashOut = function() {
   return this.chunks.length === 3 &&
-    this.chunks[0] === Opcode('OP_HASH160').toNumber() &&
+    this.chunks[0].opcodenum === Opcode('OP_HASH160').toNumber() &&
     this.chunks[1].buf &&
     this.chunks[1].buf.length === 20 &&
-    this.chunks[2] === Opcode('OP_EQUAL').toNumber();
+    this.chunks[2].opcodenum === Opcode('OP_EQUAL').toNumber();
 };
 
 /** 
@@ -272,9 +269,7 @@ Script.prototype.isScriptHashIn = function() {
     return false;
   }
   var redeemScript = new Script(scriptBuf);
-  console.log(redeemScript.toString());
   var type = redeemScript.classify();
-  console.log('type='+type);
   return type !== Script.types.UNKNOWN;
 };
 
@@ -288,15 +283,16 @@ Script.prototype.isMultisigOut = function() {
       return obj.buf && bufferUtil.isBuffer(obj.buf);
     }) &&
     Opcode.isSmallIntOp(this.chunks[this.chunks.length - 2].opcodenum) &&
-    this.chunks[this.chunks.length - 1] === Opcode.map.OP_CHECKMULTISIG);
+    this.chunks[this.chunks.length - 1].opcodenum === Opcode.map.OP_CHECKMULTISIG);
 };
 
 
 /**
- * @returns true if this is a mutlsig input script
+ * @returns true if this is a multisig input script
  */
 Script.prototype.isMultisigIn = function() {
-  return this.chunks[0] === 0 &&
+  return this.chunks.length >= 2 &&
+    this.chunks[0].opcodenum === 0 &&
     this.chunks.slice(1, this.chunks.length).every(function(obj) {
       return obj.buf &&
         bufferUtil.isBuffer(obj.buf) &&
@@ -308,12 +304,13 @@ Script.prototype.isMultisigIn = function() {
  * @returns true if this is an OP_RETURN data script
  */
 Script.prototype.isDataOut = function() {
-  return (this.chunks[0].opcodenum === Opcode('OP_RETURN').toNumber() &&
+  return this.chunks.length >= 1 &&
+    this.chunks[0].opcodenum === Opcode('OP_RETURN').toNumber() &&
     (this.chunks.length === 1 ||
       (this.chunks.length === 2 &&
         this.chunks[1].buf &&
         this.chunks[1].buf.length <= 40 &&
-        this.chunks[1].length === this.chunks.len)));
+        this.chunks[1].length === this.chunks.len));
 };
 
 /**
@@ -322,8 +319,7 @@ Script.prototype.isDataOut = function() {
  */
 Script.prototype.isPushOnly = function() {
   return _.every(this.chunks, function(chunk) {
-    var opcodenum = chunk.opcodenum;
-    return !_.isUndefined(opcodenum) || chunk <= Opcode.map.OP_16;
+    return chunk.opcodenum <= Opcode.map.OP_16;
   });
 };
 
@@ -431,7 +427,9 @@ Script.prototype._addOpcode = function(opcode, prepend) {
   } else {
     op = Opcode(opcode).toNumber();
   }
-  this._insertAtPosition(op, prepend);
+  this._insertAtPosition({
+    opcodenum: op
+  }, prepend);
   return this;
 };
 
@@ -462,7 +460,7 @@ Script.prototype._addBuffer = function(buf, prepend) {
 Script.prototype.removeCodeseparators = function() {
   var chunks = [];
   for (var i = 0; i < this.chunks.length; i++) {
-    if (this.chunks[i] !== Opcode.OP_CODESEPARATOR) {
+    if (this.chunks[i].opcodenum !== Opcode.OP_CODESEPARATOR) {
       chunks.push(this.chunks[i]);
     }
   }