some more email work for smtp errors

internal/email/email.go

@@ -1,25 +1,19 @@
 package email
 
 import (
+	"crypto/tls"
 	"fmt"
 	"log"
+	"net/smtp"
 	"net/url"
 	"strings"
-	"time"
 
 	"github.com/rideaware/admin-panel/internal/config"
 	"github.com/rideaware/admin-panel/internal/database"
-
-	"github.com/wneessen/go-mail"
 )
 
 // SendUpdate sends a newsletter with the given subject and body to all subscriber emails stored in the database.
 // It returns a human-readable status message and, when subscriber retrieval fails, the underlying error.
-// - If retrieving subscribers fails: returns "Failed to retrieve subscribers" and the error.
-// - If no subscribers are found: returns "No subscribers found." and nil.
-// - If sending to a specific subscriber fails: returns "Failed to send to <email>" and nil.
-// - On success: returns "Email has been sent to all subscribers." and nil.
-// Note: logging the newsletter entry in the database is attempted after sending and any logging failure is non-fatal.
 func SendUpdate(subject, body string) (string, error) {
 	subscribers, err := database.GetAllEmails()
 	if err != nil {
@@ -28,6 +22,7 @@ func SendUpdate(subject, body string) (string, error) {
 	if len(subscribers) == 0 {
 		return "No subscribers found.", nil
 	}
+
 	var succeeded, failed int
 	for _, email := range subscribers {
 		if send(subject, body, email) {
@@ -36,88 +31,118 @@ func SendUpdate(subject, body string) (string, error) {
 			failed++
 		}
 	}
+
 	if err := database.LogNewsletter(subject, body); err != nil {
 		log.Printf("Error logging newsletter: %v", err)
 	}
+
 	if failed == 0 {
 		return fmt.Sprintf("Email sent to all %d subscribers.", succeeded), nil
 	}
 	return fmt.Sprintf("Sent to %d/%d subscribers; %d failed.", succeeded, succeeded+failed, failed), nil
 }
 
-// send constructs and sends an HTML newsletter update to the specified recipient using the current SMTP configuration.
-// It embeds an unsubscribe link for the recipient and returns true if the message was sent successfully, false if client creation, message setup, or sending fails.
+// send constructs and sends an HTML newsletter update to the specified recipient
 func send(subject, body, recipient string) bool {
 	cfg := config.Current
 
-	var opts []mail.ClientOption
-	opts = append(opts,
-		mail.WithPort(cfg.SMTPPort),
-		mail.WithSMTPAuth(mail.SMTPAuthPlain),
-		mail.WithUsername(cfg.SMTPUser),
-		mail.WithPassword(cfg.SMTPPassword),
-		mail.WithTimeout(10*time.Second),
-	)
+	log.Printf("Attempting to send email to %s via %s:%d", recipient, cfg.SMTPServer, cfg.SMTPPort)
 
-	// Use SSL for port 465, STARTTLS for others
-	if cfg.SMTPPort == 465 {
-		opts = append(opts, mail.WithSSL())
-	} else {
-		opts = append(opts, mail.WithTLSPolicy(mail.TLSMandatory))
-	}
-
-	client, err := mail.NewClient(cfg.SMTPServer, opts...)
-	if err != nil {
-		log.Printf("Failed to create mail client: %v", err)
-		return false
-	}
-	defer client.Close()
-
-	m := mail.NewMsg()
-	if err := m.From(cfg.SenderEmail); err != nil {
-		log.Printf("Failed to set from: %v", err)
-		return false
-	}
-	if err := m.To(recipient); err != nil {
-		log.Printf("Failed to set to: %v", err)
-		return false
-	}
-	m.Subject(subject)
+	addr := fmt.Sprintf("%s:%d", cfg.SMTPServer, cfg.SMTPPort)
 
 	unsubLink := fmt.Sprintf("https://%s/unsubscribe?email=%s",
 		cfg.BaseURL, url.QueryEscape(recipient))
 
-	// Build HTML body with unsubscribe link
 	htmlBody := buildHTMLBody(body, unsubLink)
-	m.SetBodyString(mail.TypeTextHTML, htmlBody)
+	message := buildMessage(cfg.SenderEmail, recipient, subject, htmlBody)
 
-	if err := client.Send(m); err != nil {
-		log.Printf("Failed to send email to %s: %v", recipient, err)
+	// Create TLS connection
+	tlsconfig := &tls.Config{
+		ServerName: cfg.SMTPServer,
+	}
+
+	conn, err := tls.Dial("tcp", addr, tlsconfig)
+	if err != nil {
+		log.Printf("Failed to connect to SMTP %s: %v", addr, err)
 		return false
 	}
+	defer conn.Close()
+
+	// Create SMTP client
+	client, err := smtp.NewClient(conn, cfg.SMTPServer)
+	if err != nil {
+		log.Printf("Failed to create SMTP client: %v", err)
+		return false
+	}
+	defer client.Close()
+
+	// Authenticate
+	auth := smtp.PlainAuth("", cfg.SMTPUser, cfg.SMTPPassword, cfg.SMTPServer)
+	if err := client.Auth(auth); err != nil {
+		log.Printf("SMTP auth failed for %s: %v", cfg.SMTPUser, err)
+		return false
+	}
+
+	// Send the email
+	if err := client.Mail(cfg.SenderEmail); err != nil {
+		log.Printf("MAIL command failed: %v", err)
+		return false
+	}
+
+	if err := client.Rcpt(recipient); err != nil {
+		log.Printf("RCPT command failed for %s: %v", recipient, err)
+		return false
+	}
+
+	w, err := client.Data()
+	if err != nil {
+		log.Printf("DATA command failed: %v", err)
+		return false
+	}
+
+	_, err = w.Write([]byte(message))
+	if err != nil {
+		log.Printf("Failed to write message: %v", err)
+		return false
+	}
+
+	err = w.Close()
+	if err != nil {
+		log.Printf("Failed to close DATA: %v", err)
+		return false
+	}
+
+	client.Quit()
 
 	log.Printf("Update email sent to: %s", recipient)
 	return true
 }
 
+func buildMessage(from, to, subject, body string) string {
+	msg := fmt.Sprintf("From: %s\r\n", from)
+	msg += fmt.Sprintf("To: %s\r\n", to)
+	msg += fmt.Sprintf("Subject: %s\r\n", subject)
+	msg += "MIME-Version: 1.0\r\n"
+	msg += "Content-Type: text/html; charset=\"utf-8\"\r\n"
+	msg += "\r\n"
+	msg += body
+	return msg
+}
+
 // buildHTMLBody constructs the final HTML email body by appending an unsubscribe footer to the user-provided content.
-// It handles both complete HTML documents and HTML fragments.
 func buildHTMLBody(body, unsubLink string) string {
 	footer := fmt.Sprintf(
 		"<br><br><hr><p style='font-size: 12px; color: #666;'>If you ever wish to unsubscribe, "+
 			"please click <a href='%s'>here</a>.</p>",
 		unsubLink)
 
-	// If body contains closing html tag, insert before it
 	if strings.Contains(strings.ToLower(body), "</html>") {
 		return strings.Replace(body, "</html>", footer+"</html>", 1)
 	}
 
-	// If body contains closing body tag, insert before it
 	if strings.Contains(strings.ToLower(body), "</body>") {
 		return strings.Replace(body, "</body>", footer+"</body>", 1)
 	}
 
-	// Otherwise just append
 	return body + footer
 }