Refactoring and cleanup

* Split CLI client into separate project
* Convert more functions to follow common Golang idioms e.g io.Reader, io.Writer
* Use ldflags for versioning
* Misc cleanup and simplification

1 files changed, 41 insertions, 15 deletions

diff --git a/hotline/transaction.go b/hotline/transaction.go
index d9bbc22..7883bfb 100644
--- a/hotline/transaction.go
+++ b/hotline/transaction.go
@@ -1,10 +1,12 @@
 package hotline
 
 import (
+	"bufio"
 	"bytes"
 	"encoding/binary"
 	"errors"
 	"fmt"
+	"io"
 	"math/rand"
 	"slices"
 )
@@ -71,8 +73,6 @@ const (
 )
 
 type Transaction struct {
-	clientID *[]byte
-
 	Flags      byte   // Reserved (should be 0)
 	IsReply    byte   // Request (0) or reply (1)
 	Type       []byte // Requested operation (user defined)
@@ -82,6 +82,9 @@ type Transaction struct {
 	DataSize   []byte // Size of data in this transaction part. This allows splitting large transactions into smaller parts.
 	ParamCount []byte // Number of the parameters for this transaction
 	Fields     []Field
+
+	clientID   *[]byte // Internal identifier for target client
+	readOffset int     // Internal offset to track read progress
 }
 
 func NewTransaction(t int, clientID *[]byte, fields ...Field) *Transaction {
@@ -113,9 +116,19 @@ func (t *Transaction) Write(p []byte) (n int, err error) {
 	if tranLen > len(p) {
 		return n, errors.New("buflen too small for tranLen")
 	}
-	fields, err := ReadFields(p[20:22], p[22:tranLen])
-	if err != nil {
-		return n, err
+
+	// Create a new scanner for parsing incoming bytes into transaction tokens
+	scanner := bufio.NewScanner(bytes.NewReader(p[22:tranLen]))
+	scanner.Split(fieldScanner)
+
+	for i := 0; i < int(binary.BigEndian.Uint16(p[20:22])); i++ {
+		scanner.Scan()
+
+		var field Field
+		if _, err := field.Write(scanner.Bytes()); err != nil {
+			return 0, fmt.Errorf("error reading field: %w", err)
+		}
+		t.Fields = append(t.Fields, field)
 	}
 
 	t.Flags = p[0]
@@ -126,7 +139,6 @@ func (t *Transaction) Write(p []byte) (n int, err error) {
 	t.TotalSize = p[12:16]
 	t.DataSize = p[16:20]
 	t.ParamCount = p[20:22]
-	t.Fields = fields
 
 	return len(p), err
 }
@@ -177,8 +189,8 @@ func ReadFields(paramCount []byte, buf []byte) ([]Field, error) {
 		}
 
 		fields = append(fields, Field{
-			ID:        fieldID,
-			FieldSize: fieldSize,
+			ID:        [2]byte(fieldID),
+			FieldSize: [2]byte(fieldSize),
 			Data:      buf[4 : 4+fieldSizeInt],
 		})
 
@@ -192,18 +204,23 @@ func ReadFields(paramCount []byte, buf []byte) ([]Field, error) {
 	return fields, nil
 }
 
-func (t *Transaction) MarshalBinary() (data []byte, err error) {
+// Read implements the io.Reader interface for Transaction
+func (t *Transaction) Read(p []byte) (int, error) {
 	payloadSize := t.Size()
 
 	fieldCount := make([]byte, 2)
 	binary.BigEndian.PutUint16(fieldCount, uint16(len(t.Fields)))
 
-	var fieldPayload []byte
+	bbuf := new(bytes.Buffer)
+
 	for _, field := range t.Fields {
-		fieldPayload = append(fieldPayload, field.Payload()...)
+		_, err := bbuf.ReadFrom(&field)
+		if err != nil {
+			return 0, fmt.Errorf("error reading field: %w", err)
+		}
 	}
 
-	return slices.Concat(
+	buf := slices.Concat(
 		[]byte{t.Flags, t.IsReply},
 		t.Type,
 		t.ID,
@@ -211,8 +228,17 @@ func (t *Transaction) MarshalBinary() (data []byte, err error) {
 		payloadSize,
 		payloadSize, // this is the dataSize field, but seeming the same as totalSize
 		fieldCount,
-		fieldPayload,
-	), err
+		bbuf.Bytes(),
+	)
+
+	if t.readOffset >= len(buf) {
+		return 0, io.EOF // All bytes have been read
+	}
+
+	n := copy(p, buf[t.readOffset:])
+	t.readOffset += n
+
+	return n, nil
 }
 
 // Size returns the total size of the transaction payload
@@ -231,7 +257,7 @@ func (t *Transaction) Size() []byte {
 
 func (t *Transaction) GetField(id int) Field {
 	for _, field := range t.Fields {
-		if id == int(binary.BigEndian.Uint16(field.ID)) {
+		if id == int(binary.BigEndian.Uint16(field.ID[:])) {
 			return field
 		}
 	}