v1.0.0

backend/utils/mail/eml_reader.go

@@ -0,0 +1,101 @@
+package internal
+
+import (
+	"fmt"
+	"io"
+	"net/mail"
+	"os"
+	"unicode/utf8"
+
+	"github.com/DusanKasan/parsemail"
+	"golang.org/x/text/encoding/charmap"
+	"golang.org/x/text/transform"
+)
+
+type EmailAttachment struct {
+	Filename    string `json:"filename"`
+	ContentType string `json:"contentType"`
+	Data        []byte `json:"data"`
+}
+
+type EmailData struct {
+	From        string            `json:"from"`
+	To          []string          `json:"to"`
+	Cc          []string          `json:"cc"`
+	Bcc         []string          `json:"bcc"`
+	Subject     string            `json:"subject"`
+	Body        string            `json:"body"`
+	Attachments []EmailAttachment `json:"attachments"`
+}
+
+func ReadEmlFile(filePath string) (*EmailData, error) {
+	file, err := os.Open(filePath)
+	if err != nil {
+		return nil, fmt.Errorf("failed to open file: %w", err)
+	}
+	defer file.Close()
+
+	email, err := parsemail.Parse(file)
+	if err != nil {
+		return nil, fmt.Errorf("failed to parse email: %w", err)
+	}
+
+	// Format addresses
+	formatAddress := func(addr []*mail.Address) []string {
+		var result []string
+		for _, a := range addr {
+			result = append(result, convertToUTF8(a.String()))
+		}
+		return result
+	}
+
+	// Determine body (prefer HTML)
+	body := email.HTMLBody
+	if body == "" {
+		body = email.TextBody
+	}
+
+	// Process attachments
+	var attachments []EmailAttachment
+	for _, att := range email.Attachments {
+		data, err := io.ReadAll(att.Data)
+		if err != nil {
+			continue // Handle error or skip? Skipping for now.
+		}
+		attachments = append(attachments, EmailAttachment{
+			Filename:    att.Filename,
+			ContentType: att.ContentType,
+			Data:        data,
+		})
+	}
+
+	// Format From
+	var from string
+	if len(email.From) > 0 {
+		from = email.From[0].String()
+	}
+
+	return &EmailData{
+		From:        convertToUTF8(from),
+		To:          formatAddress(email.To),
+		Cc:          formatAddress(email.Cc),
+		Bcc:         formatAddress(email.Bcc),
+		Subject:     convertToUTF8(email.Subject),
+		Body:        convertToUTF8(body),
+		Attachments: attachments,
+	}, nil
+}
+
+func convertToUTF8(s string) string {
+	if utf8.ValidString(s) {
+		return s
+	}
+
+	// If invalid UTF-8, assume Windows-1252 (superset of ISO-8859-1)
+	decoder := charmap.Windows1252.NewDecoder()
+	decoded, _, err := transform.String(decoder, s)
+	if err != nil {
+		return s // Return as-is if decoding fails
+	}
+	return decoded
+}