refactor(services): Extract barcode generation

services/barcode.go

@@ -0,0 +1,69 @@
+package services
+
+import (
+	"bytes"
+	"fmt"
+	"image/png"
+	"slices"
+
+	"github.com/boombuler/barcode"
+	"github.com/boombuler/barcode/code128"
+	"github.com/boombuler/barcode/ean"
+	"github.com/boombuler/barcode/qr"
+)
+
+type BarcodeGenerator interface {
+	GenerateBarcode(format string, content string) (bytes.Buffer, error)
+	IsTypeSupported(format string) bool
+}
+
+type DefaultBarcodeGenerator struct {
+}
+
+func (b *DefaultBarcodeGenerator) GenerateBarcode(format string, content string, width int, height int) (bytes.Buffer, error) {
+	if !b.IsTypeSupported(format) {
+		return bytes.Buffer{}, fmt.Errorf("unsupported barcode type: %s", format)
+	}
+
+	var generatedCode barcode.Barcode
+	var err error
+
+	switch format {
+	case "ean13":
+		generatedCode, err = ean.Encode(content)
+		if err != nil {
+			return bytes.Buffer{}, err
+		}
+		break
+	case "code128":
+		generatedCode, err = code128.Encode(content)
+		if err != nil {
+			return bytes.Buffer{}, err
+		}
+		break
+	case "qr":
+		generatedCode, err = qr.Encode(content, qr.M, qr.AlphaNumeric)
+		if err != nil {
+			return bytes.Buffer{}, err
+		}
+		break
+	}
+
+	scaledCode, err := barcode.Scale(generatedCode, width, height)
+	if err != nil {
+		return bytes.Buffer{}, err
+	}
+
+	var buf bytes.Buffer
+	err = png.Encode(&buf, scaledCode)
+	if err != nil {
+		return bytes.Buffer{}, err
+	}
+
+	return buf, nil
+}
+
+func (b *DefaultBarcodeGenerator) IsTypeSupported(format string) bool {
+	supportedTypes := []string{"ean13", "code128", "qr"}
+	return slices.Contains(supportedTypes, format)
+}