From 19347800c8cf8da680d1db58b0c4d87019ee96c5 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marius=20Kl=C3=B6ck?= <marius.kloeck@antwire.net>
Date: Fri, 22 Apr 2022 18:11:33 +0200
Subject: [PATCH] Optimizations

---
 chain/block.go       | 24 ++++++++++++------------
 chain/transaction.go | 13 +++++++++----
 keymgmt/keymgmt.go   |  2 +-
 main.go              |  6 ------
 monoblock_test.go    | 17 +++++++++++++++++
 5 files changed, 39 insertions(+), 23 deletions(-)
 create mode 100644 monoblock_test.go

diff --git a/chain/block.go b/chain/block.go
index 6f83730..7d01751 100644
--- a/chain/block.go
+++ b/chain/block.go
@@ -1,11 +1,9 @@
 package chain
 
 import (
-	"bytes"
-	"encoding/gob"
+	"encoding/hex"
 	"fmt"
 	"golang.org/x/crypto/sha3"
-	"log"
 	"math/rand"
 )
 
@@ -29,23 +27,25 @@ func (b *block) AddTransaction(t transaction) {
 func (b block) GenerateHash(difficulty int) []byte {
 	found := false
 	var compBytes []byte
+	var compString string
 	for i := 0; i < difficulty; i++ {
 		compBytes = append(compBytes, []byte("0x00")...)
 	}
+	for i := 0; i < difficulty; i++ {
+		compString += "0"
+	}
 	for !found {
 		random := make([]byte, 64)
 		rand.Read(random)
 		b.Nonce = random
-		var buf bytes.Buffer
-		err := gob.NewEncoder(&buf).Encode(b.Nonce)
-		if err != nil {
-			log.Fatal(err)
-		}
+
 		hasher := sha3.New512()
 		hasher.Write(b.ToBytes())
 		hash := hasher.Sum(nil)
-		fmt.Printf("\033[2K\r%x\n", hash)
-		if checkAllZero(XorSlice(hash[:difficulty], compBytes)) {
+		//if checkAllZero(XorSlice(hash[:difficulty], compBytes)) {
+		hexstring := hex.EncodeToString(hash)
+		fmt.Printf("%x\n", hash)
+		if hexstring[:difficulty] == compString {
 			return hash
 		}
 	}
@@ -57,19 +57,19 @@ func (b block) ToBytes() []byte {
 	for i := 0; i < len(b.Transactions); i++ {
 		bytes = append(bytes, b.Transactions[i].ToBytes()...)
 	}
+	bytes = append(bytes, b.HashPrevious...)
 	bytes = append(bytes, b.Nonce...)
 	return bytes
 }
 
 func XorSlice(a []byte, b []byte) []byte {
-	for i, _ := range a {
+	for i := range a {
 		a[i] = a[i] ^ b[i]
 	}
 	return a
 }
 
 func checkAllZero(a []byte) bool {
-	fmt.Printf("Checking if all zero: %x\n", a)
 	for i, _ := range a {
 		if a[i] != 0x00 {
 			return false
diff --git a/chain/transaction.go b/chain/transaction.go
index 1f8ac52..0e57469 100644
--- a/chain/transaction.go
+++ b/chain/transaction.go
@@ -14,11 +14,11 @@ type transaction struct {
 	Src       string
 	Dst       string
 	Amount    int
-	Timestamp time.Time
+	Timestamp int64
 }
 
 func NewTransaction(source string, dst string, amount int) transaction {
-	return transaction{Src: source, Dst: dst, Amount: amount, Timestamp: time.Now()}
+	return transaction{Src: source, Dst: dst, Amount: amount, Timestamp: time.Now().Unix()}
 }
 
 func (ta transaction) SignTransaction(privKey *rsa.PrivateKey, d int) ([]byte, error) {
@@ -36,8 +36,13 @@ func (ta transaction) HashTransaction() []byte {
 func (ta transaction) ToBytes() []byte {
 	bytes := []byte(ta.Src)
 	bytes = append(bytes, []byte(ta.Dst)...)
-	//fmt.Printf("%s", ta.Dst)
 	bytes = append(bytes, byte(ta.Amount))
-	bytes = append(bytes, []byte(ta.Timestamp.String())...)
+	//bytes = append(bytes, []byte(ta.Timestamp))
 	return bytes
 }
+
+func (ta transaction) ToBytesSerialize() []byte {
+	var buf bytes.Buffer
+	gob.NewEncoder(&buf).Encode(ta)
+	return buf.Bytes()
+}
diff --git a/keymgmt/keymgmt.go b/keymgmt/keymgmt.go
index 3ce54e2..1ac4b6d 100644
--- a/keymgmt/keymgmt.go
+++ b/keymgmt/keymgmt.go
@@ -16,7 +16,7 @@ type Address struct {
 }
 
 func GenerateAddress() *Address {
-	key, err := rsa.GenerateKey(rand.Reader, 1024)
+	key, err := rsa.GenerateKey(rand.Reader, 512)
 
 	if err != nil {
 		log.Fatal(err)
diff --git a/main.go b/main.go
index ac43c4a..c676911 100644
--- a/main.go
+++ b/main.go
@@ -2,7 +2,6 @@ package main
 
 import (
 	"bufio"
-	"encoding/hex"
 	"fmt"
 	"monoblock/chain"
 	"monoblock/keymgmt"
@@ -12,11 +11,6 @@ import (
 const AMOUNT int = 100
 
 func main() {
-	by1, _ := hex.DecodeString("0001020304")
-	by2, _ := hex.DecodeString("0001020304")
-
-	fmt.Printf("%x", chain.XorSlice(by1, by2))
-
 	addr1 := keymgmt.GenerateAddress()
 	addr2 := keymgmt.GenerateAddress()
 	addr3 := keymgmt.GenerateAddress()
diff --git a/monoblock_test.go b/monoblock_test.go
new file mode 100644
index 0000000..f8b967f
--- /dev/null
+++ b/monoblock_test.go
@@ -0,0 +1,17 @@
+package main
+
+import (
+	"fmt"
+	"monoblock/chain"
+	"monoblock/keymgmt"
+	"testing"
+)
+
+func TestGenerateAddress(t *testing.T) {
+	addr1 := keymgmt.GenerateAddress()
+	addr2 := keymgmt.GenerateAddress()
+	ta1 := chain.NewTransaction(addr1.GetAddress(), addr2.GetAddress(), 100)
+
+	fmt.Printf("%x\n", ta1.ToBytes())
+	fmt.Printf("%x\n", ta1.ToBytesSerialize())
+}