feat: Allow plaintext e-mails for SMTP

email.go

@@ -42,9 +42,9 @@ func (m Model) sendEmailCmd() tea.Cmd {
 		bcc := strings.Split(m.Bcc.Value(), ToSeparator)
 		switch m.DeliveryMethod {
 		case SMTP:
-			err = sendSMTPEmail(to, cc, bcc, m.From.Value(), m.Subject.Value(), m.Body.Value(), attachments)
+			err = sendSMTPEmail(to, cc, bcc, m.From.Value(), m.Subject.Value(), m.Body.Value(), plaintext, attachments)
 		case Resend:
-			err = sendResendEmail(to, cc, bcc, m.From.Value(), m.Subject.Value(), m.Body.Value(), attachments)
+			err = sendResendEmail(to, cc, bcc, m.From.Value(), m.Subject.Value(), m.Body.Value(), plaintext, attachments)
 		default:
 			err = errors.New("[ERROR]: unknown delivery method")
 		}
@@ -65,7 +65,7 @@ const (
 	gmailSMTPPort = 587
 )
 
-func sendSMTPEmail(to, cc, bcc []string, from, subject, body string, attachments []string) error {
+func sendSMTPEmail(to, cc, bcc []string, from, subject, body string, plaintext bool, attachments []string) error {
 	server := mail.NewSMTPClient()
 
 	var err error
@@ -116,7 +116,7 @@ func sendSMTPEmail(to, cc, bcc []string, from, subject, body string, attachments
 	html := bytes.NewBufferString("")
 	convertErr := goldmark.Convert([]byte(body), html)
 
-	if convertErr != nil {
+	if (plaintext) || (convertErr != nil) {
 		email.SetBody(mail.TextPlain, body)
 	} else {
 		email.SetBody(mail.TextHTML, html.String())
@@ -135,25 +135,28 @@ func sendSMTPEmail(to, cc, bcc []string, from, subject, body string, attachments
 	return nil
 }
 
-func sendResendEmail(to, cc, bcc []string, from, subject, body string, attachments []string) error {
+func sendResendEmail(to, cc, bcc []string, from, subject, body string, plaintext bool, attachments []string) error {
 	client := resend.NewClient(resendAPIKey)
 
 	html := bytes.NewBufferString("")
-	// If the conversion fails, we'll simply send the plain-text body.
-	if unsafe {
-		markdown := goldmark.New(
-			goldmark.WithRendererOptions(
-				renderer.WithUnsafe(),
-			),
-			goldmark.WithExtensions(
-				extension.Strikethrough,
-				extension.Table,
-				extension.Linkify,
-			),
-		)
-		_ = markdown.Convert([]byte(body), html)
-	} else {
-		_ = goldmark.Convert([]byte(body), html)
+	// If the conversion fails or plaintext is requested,
+	// we'll simply send the plain-text body.
+	if !plaintext {
+		if unsafe {
+			markdown := goldmark.New(
+				goldmark.WithRendererOptions(
+					renderer.WithUnsafe(),
+				),
+				goldmark.WithExtensions(
+					extension.Strikethrough,
+					extension.Table,
+					extension.Linkify,
+				),
+			)
+			_ = markdown.Convert([]byte(body), html)
+		} else {
+			_ = goldmark.Convert([]byte(body), html)
+		}
 	}
 
 	request := &resend.SendEmailRequest{

main.go

@@ -30,6 +30,10 @@ const envTrue = "true"
 // Resend delivery (as opposed to API key delivery).
 const PopOAuthResend = "POP_OAUTH_RESEND"
 
+// PopPlaintext control whether the message should be sent in plaintext.
+// Boolean, default `false`.
+const PopPlaintext = "POP_PLAINTEXT"
+
 // ResendAPIKey is the environment variable that enables Resend as a delivery
 // method and uses it to send the email.
 const ResendAPIKey = "RESEND_API_KEY" //nolint:gosec
@@ -71,6 +75,7 @@ var (
 	bcc                    []string
 	subject                string
 	body                   string
+	plaintext              bool
 	attachments            []string
 	preview                bool
 	unsafe                 bool
@@ -220,9 +225,9 @@ See "pop skill" for a full skill definition for AI agents.`,
 			var err error
 			switch deliveryMethod {
 			case SMTP:
-				err = sendSMTPEmail(to, cc, bcc, from, subject, body, attachments)
+				err = sendSMTPEmail(to, cc, bcc, from, subject, body, plaintext, attachments)
 			case Resend:
-				err = sendResendEmail(to, cc, bcc, from, subject, body, attachments)
+				err = sendResendEmail(to, cc, bcc, from, subject, body, plaintext, attachments)
 			default:
 				err = fmt.Errorf("unknown delivery method")
 			}
@@ -373,6 +378,8 @@ func init() {
 	rootCmd.Flags().StringSliceVarP(&attachments, "attach", "a", []string{}, "Email's attachments")
 	rootCmd.Flags().StringSliceVarP(&to, "to", "t", []string{}, "Recipients")
 	rootCmd.Flags().StringVarP(&body, "body", "b", "", "Email's contents")
+	envPlaintext := os.Getenv(PopPlaintext) == "true"
+	rootCmd.Flags().BoolVar(&plaintext, "plaintext", envPlaintext, "Whether to send email in plaintext")
 	envFrom := os.Getenv(PopFrom)
 	rootCmd.Flags().StringVarP(&from, "from", "f", envFrom, "Email's sender"+commentStyle.Render("($"+PopFrom+")"))
 	rootCmd.Flags().StringVarP(&subject, "subject", "s", "", "Email's subject")