From 8d372a34eb7b25fc73cb69124ac02a2c29c539b0 Mon Sep 17 00:00:00 2001
From: OsauravO <saurav1hasyo@gmail.com>
Date: Fri, 26 Apr 2024 23:50:24 +0530
Subject: [PATCH] transaction serialization fixed

---
 main.go | 60 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 60 insertions(+)

diff --git a/main.go b/main.go
index f514666..0a34d8e 100644
--- a/main.go
+++ b/main.go
@@ -340,7 +340,67 @@ func Ordering() (uint64, []string, []string) {
 	fmt.Println("reward: ", reward)
 	return reward, permittedTxIDs, permittedWTxIDs
 }
+func SerializeTransaction(tx *Transaction) ([]byte, error) {
+
+	var serialized []byte
+	// Serialize version
+	versionBytes := make([]byte, 4)
+	binary.LittleEndian.PutUint32(versionBytes, tx.Version)
+	serialized = append(serialized, versionBytes...)
+	// Serialize vin count
+	vinCount := uint64(len(tx.Vin))
+	serialized = append(serialized, SerializeVarInt(vinCount)...)
+
+	// Serialize vin
+	for _, vin := range tx.Vin {
+		txidBytes, _ := hex.DecodeString(vin.TxID)
+		serialized = append(serialized, ReverseBytes(txidBytes)...)
+
+		voutBytes := make([]byte, 4)
+		binary.LittleEndian.PutUint32(voutBytes, vin.Vout)
+		serialized = append(serialized, voutBytes...)
+
+		Scriptsig_bytes, _ := hex.DecodeString(vin.Scriptsig)
+		length_scriptsig := (uint64(len(Scriptsig_bytes)))
+		serialized = append(serialized, SerializeVarInt(length_scriptsig)...)
+
+		serialized = append(serialized, Scriptsig_bytes...)
+
+		// Serialize sequence
+		sequenceBytes := make([]byte, 4)
+		binary.LittleEndian.PutUint32(sequenceBytes, vin.Sequence)
+		serialized = append(serialized, sequenceBytes...)
+
+	}
 
+	// Serialize vout count
+	voutCount := uint64(len(tx.Vout))
+	serialized = append(serialized, SerializeVarInt(voutCount)...)
+
+	// Serialize vout
+	for _, vout := range tx.Vout {
+		valueBytes := make([]byte, 8)
+		binary.LittleEndian.PutUint64(valueBytes, vout.Value)
+		serialized = append(serialized, valueBytes...)
+
+		// Serialize scriptPubKey length
+		scriptPubKeyBytes, err := hex.DecodeString(vout.Scriptpubkey)
+		scriptPubKeyLen := uint64(len(scriptPubKeyBytes)) // Divide by 2 if appending the length of the non decoded form to get byte length since scriptPubKey is hex encoded
+		serialized = append(serialized, SerializeVarInt(scriptPubKeyLen)...)
+
+		// Serialize scriptPubKey
+		if err != nil {
+			return nil, err
+		}
+		serialized = append(serialized, scriptPubKeyBytes...)
+	}
+	//Locktime
+	locktimeBytes := make([]byte, 4)
+	binary.LittleEndian.PutUint32(locktimeBytes, tx.Locktime)
+	serialized = append(serialized, locktimeBytes...)
+
+	return serialized, nil
+}
 func main() {
 	networkReward, transactionIDs, _ := Ordering()