From fdc502acba9df74b26fc984cd4e3108f2769fe0a Mon Sep 17 00:00:00 2001
From: Chris Stewart <stewart.chris1234@gmail.com>
Date: Sat, 9 Jan 2016 18:20:50 -0600
Subject: [PATCH] Successfully parsing a byte array into an asm output script

---
 .../script/parsing/ScriptParser.scala         | 31 +++++++++++++++----
 .../script/parsing/ScriptParserTest.scala     |  4 +--
 2 files changed, 27 insertions(+), 8 deletions(-)

diff --git a/src/main/scala/org/scalacoin/script/parsing/ScriptParser.scala b/src/main/scala/org/scalacoin/script/parsing/ScriptParser.scala
index 229cdcaaf8..36164f46d7 100644
--- a/src/main/scala/org/scalacoin/script/parsing/ScriptParser.scala
+++ b/src/main/scala/org/scalacoin/script/parsing/ScriptParser.scala
@@ -1,14 +1,15 @@
 package org.scalacoin.script.parsing
 
 import org.scalacoin.script._
-import org.scalacoin.script.constant.{OP_0, ScriptConstantImpl, ScriptToken}
+import org.scalacoin.script.constant._
+import org.scalacoin.util.ScalacoinUtil
 
 import scala.annotation.tailrec
 
 /**
  * Created by chris on 1/7/16.
  */
-trait ScriptParser {
+trait ScriptParser extends ScalacoinUtil {
   /**
    * Parses an output script of a transaction
    * @param str
@@ -36,9 +37,27 @@ trait ScriptParser {
    * @return
    */
   def parse(bytes : List[Byte]) : List[ScriptToken] = {
-    val operations : List[ScriptToken] = for {
-      byte <- bytes
-    } yield ScriptOperationFactory.fromOpCode(byte).get
-    operations
+
+    @tailrec
+    def loop(bytes : List[Byte], accum : List[ScriptToken]) : List[ScriptToken] = {
+      bytes match {
+        case h :: t =>
+          val op  = ScriptOperationFactory.fromOpCode(h).get
+            //means that we need to push x amount of bytes on to the stack
+           if (ScriptNumberFactory.operations.contains(op)) {
+             val (constant,tail) = pushConstant(ScriptNumberImpl(op.opCode),t)
+             loop(tail, constant :: accum)
+          } else loop(t, op :: accum)
+        case Nil => accum
+      }
+
+    }
+    loop(bytes, List()).reverse
+  }
+
+  def pushConstant(op : ScriptNumber, bytes : List[Byte]) : (ScriptConstant, List[Byte]) = {
+    val finalIndex = op.opCode
+    val constant : ScriptConstantImpl = ScriptConstantImpl(encodeHex(bytes.slice(0,finalIndex)))
+    (constant, bytes.slice(finalIndex,bytes.size))
   }
 }
diff --git a/src/test/scala/org/scalacoin/script/parsing/ScriptParserTest.scala b/src/test/scala/org/scalacoin/script/parsing/ScriptParserTest.scala
index 5d18f87455..d9bd25326c 100644
--- a/src/test/scala/org/scalacoin/script/parsing/ScriptParserTest.scala
+++ b/src/test/scala/org/scalacoin/script/parsing/ScriptParserTest.scala
@@ -34,8 +34,8 @@ class ScriptParserTest extends FlatSpec with MustMatchers with ScriptParser with
 
   it must "parse a p2pkh input script from a byte array to script tokens" in {
     /*val byteArray = TestUtil.p2pkhInputScript.getBytes.toList*/
-    val byteArray : List[Byte] = decodeHex("76a914")
-    parse(byteArray) must be (List(OP_DUP, OP_HASH160, ScriptNumberImpl(20)))
+    val bytes : List[Byte] = decodeHex(TestUtil.p2pkhOutputScript)
+    parse(bytes) must be (TestUtil.p2pkhOutputScriptAsm)
   }
 
 }