smtp.go

package main

import (
	"crypto/tls"
	"fmt"
	"strings"

	"github.com/wneessen/go-mail"
)

// sendEmail function modified to include the reply-to header
func sendEmail(smtpServer string, smtpPort int, username string, password string, from string, to []string, replyTo string, subject, body, bodyFile string, attachments []string, tlsMode string, noAuth bool) error {
    // Create a new message
    m := mail.NewMsg()
    if err := m.From(from); err != nil {
        return err
    }

    // Set recipient(s)
    if err := m.To(to...); err != nil {
        return err
    }

    // Set the subject
    m.Subject(subject)

    // Set the body
    if bodyFile != "" {
        m.SetBodyString(mail.TypeTextHTML, body)
    } else {
        m.SetBodyString(mail.TypeTextPlain, body)
    }

    // Add attachments
    for _, attachment := range attachments {
        m.AttachFile(attachment)
    }

    // Add the reply-to header if provided
    if replyTo != "" {
        if err := m.ReplyTo(replyTo); err != nil {
        return err
    }
    }

    clientOptions := []mail.Option{
        mail.WithPort(smtpPort),
    }

    // Define client options
    if !noAuth && (username != "" || password != "") {
        clientOptions = append(
            clientOptions,
            mail.WithSMTPAuth(mail.SMTPAuthLogin),
            mail.WithUsername(username),
            mail.WithPassword(password),
        )
    }

    // Conditionally add TLS options based on tlsMode
    switch tlsMode {
    case "none":
        clientOptions = append(clientOptions, mail.WithTLSPolicy(mail.NoTLS))
    case "tls-skip":
        tlsSkipConfig := &tls.Config{
            InsecureSkipVerify: true,
            ServerName:         smtpServer,
        }
        clientOptions = append(clientOptions, mail.WithTLSConfig(tlsSkipConfig))
    case "tls":
        clientOptions = append(clientOptions, mail.WithTLSPolicy(mail.TLSMandatory))
    }

    // Create a new client using the options
    c, err := mail.NewClient(smtpServer, clientOptions...)
    if err != nil {
        fmt.Printf("Failed to create SMTP client: %v", err)
    }
    if c == nil {
        fmt.Printf("SMTP client is nil")
    }

    // Send the email
    if err := c.DialAndSend(m); err != nil {
        fmt.Printf("Error sending email: %v", err)
        return err
    }

    fmt.Printf("\nEmail sent successfully to %s from %s\n", strings.Join(to, ", "), from)
    return nil
}