fix: Fixes the errors in byte conversion of Header and Question

main.go

@@ -14,36 +14,23 @@ func main() {
 		os.Exit(1)
 	}
 	domain := os.Args[1]
-	question := types.Question{
-		QType:  1,
-		QClass: 1,
-	}
-	question.SetName(domain)
+
+	question := types.NewQuestion(domain, 1, 1)
+	generateFlag := types.GenerateFlag(0, 0, 0, 0, 1, 0, 0, 0)
+	header := types.NewHeader(22, generateFlag, 1, 0, 0, 0)
 	DNSMessage := types.DNSMessage{
-		Header: types.Header{
-			ID:      22,
-			QR:      false,
-			Opcode:  0,
-			AA:      false,
-			TC:      false,
-			RD:      true,
-			RA:      false,
-			Z:       0,
-			RCode:   0,
-			QDCount: 1,
-			ANCount: 0,
-			NSCount: 0,
-			ARCount: 0,
-		},
+		Header: *header,
 		Questions: []types.Question{
-			question,
+			*question,
 		},
 	}
 
 	fmt.Printf("Domain: %s\n", domain)
 	fmt.Printf("DNS Message: %+v\n\n", DNSMessage)
 	fmt.Printf("DNS Message in Bytes: %+v\n", DNSMessage.ToBytes())
 	fmt.Printf("DNS Message in Hex: %s\n", hex.EncodeToString(DNSMessage.ToBytes()))
+	fmt.Printf("Header in Hex: %s\n", hex.EncodeToString(header.ToBytes()))
+	fmt.Printf("Header in Hex: %s\n", hex.EncodeToString(question.ToBytes()))
 
 	// addr := &net.UDPAddr{
 	// 	IP:   net.IPv4(127, 0, 0, 1),

types/dns_message.go

@@ -2,7 +2,6 @@ package types
 
 import (
 	"bytes"
-	"encoding/binary"
 )
 
 // See https://datatracker.ietf.org/doc/html/rfc1035#section-4.1 for more information
@@ -19,7 +18,7 @@ func (m *DNSMessage) ToBytes() []byte {
 	buf := new(bytes.Buffer)
 
 	// Write the header to the buffer
-	binary.Write(buf, binary.BigEndian, m.Header)
+	buf.Write(m.Header.ToBytes())
 
 	// Write the questions to the buffer
 	for _, q := range m.Questions {

types/header.go

@@ -1,18 +1,60 @@
 package types
 
+import (
+	"bytes"
+	"encoding/binary"
+)
+
 // See https://datatracker.ietf.org/doc/html/rfc1035#section-4.1.1 for more information
 type Header struct {
-	ID      uint16
-	QR      bool
-	Opcode  uint8
-	AA      bool
-	TC      bool
-	RD      bool
-	RA      bool
-	Z       uint8
-	RCode   uint8
+	ID    uint16
+	Flags uint16
+	// QR      bool
+	// Opcode  uint8
+	// AA      bool
+	// TC      bool
+	// RD      bool
+	// RA      bool
+	// Z       uint8
+	// RCode   uint8
 	QDCount uint16
 	ANCount uint16
 	NSCount uint16
 	ARCount uint16
 }
+
+func NewHeader(id, flags, qdCount, anCount, nsCount, arCount uint16) *Header {
+	return &Header{
+		ID: id,
+		// QR:      false,
+		// Opcode:  0,
+		// AA:      false,
+		// TC:      false,
+		// RD:      false,
+		// RA:      false,
+		// Z:       0,
+		// RCode:   0,
+		Flags:   flags,
+		QDCount: qdCount,
+		ANCount: anCount,
+		NSCount: nsCount,
+		ARCount: arCount,
+	}
+}
+
+func GenerateFlag(qr, opcode, aa, tc, rd, ra, z, rcode uint16) uint16 {
+	return uint16(qr<<15 | opcode<<11 | aa<<10 | tc<<9 | rd<<8 | ra<<7 | z<<4 | rcode)
+}
+
+func (h *Header) ToBytes() []byte {
+	buf := new(bytes.Buffer)
+
+	binary.Write(buf, binary.BigEndian, h.ID)
+	binary.Write(buf, binary.BigEndian, h.Flags)
+	binary.Write(buf, binary.BigEndian, h.QDCount)
+	binary.Write(buf, binary.BigEndian, h.ANCount)
+	binary.Write(buf, binary.BigEndian, h.NSCount)
+	binary.Write(buf, binary.BigEndian, h.ARCount)
+
+	return buf.Bytes()
+}

types/question.go

@@ -3,7 +3,6 @@ package types
 import (
 	"bytes"
 	"encoding/binary"
-	"fmt"
 	"strings"
 )
 
@@ -15,24 +14,29 @@ type Question struct {
 	QClass uint16
 }
 
+func NewQuestion(name string, qType, qClass uint16) *Question {
+	q := &Question{
+		Name:   name,
+		QType:  qType,
+		QClass: qClass,
+	}
+	q.QName = convertToQName(name)
+	return q
+}
+
 func (q *Question) SetName(name string) {
 	q.Name = name
-	// Update the QName value based on some algorithm
-	// Replace this with your own algorithm
 	q.QName = convertToQName(name)
 }
 
 func convertToQName(name string) string {
-	// Implement your algorithm to convert the name to QName
-	// Example algorithm: replace '.' with '-'
-	// return strings.ReplaceAll(name, ".", "-")
 	domain_parts := strings.Split(name, ".")
 	qname := ""
 	for _, part := range domain_parts {
-		new_domain_part := fmt.Sprintf("%d%s", len(part), part)
+		new_domain_part := string(byte(len(part))) + part
 		qname += new_domain_part
 	}
-	return qname + "0"
+	return qname + "\x00"
 }
 
 func (q *Question) ToBytes() []byte {