auctiora/src/main/java/auctiora/NotificationService.java

package auctiora;

import javax.mail.Authenticator;
import javax.mail.Message.RecipientType;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import java.awt.SystemTray;
import java.awt.Toolkit;
import java.awt.TrayIcon;
import java.awt.TrayIcon.MessageType;
import java.util.Date;
import java.util.Properties;
/**
 * Service for sending notifications via desktop notifications and/or email.
 * Supports free notification methods:
 * 1. Desktop notifications (Windows/Linux/macOS system tray)
 * 2. Email via Gmail SMTP (free, requires app password)
 *
 * Configuration:
 * - For email: Set notificationEmail to your Gmail address
 * - Enable 2FA in Gmail and create an App Password
 * - Use format "smtp:username:appPassword:toEmail" for credentials
 * - Or use "desktop" for desktop-only notifications
 */
class NotificationService {
   
   private final boolean useDesktop;
   private final boolean useEmail;
   private final String  smtpUsername;
   private final String  smtpPassword;
   private final String  toEmail;
   
   /**
    * Creates a notification service.
    *
    * @param config "desktop" for desktop only, or "smtp:username:password:toEmail" for email
    * @param unusedParam Kept for compatibility (can pass empty string)
    */
   NotificationService(String config, String unusedParam) {
      
      if ("desktop".equalsIgnoreCase(config)) {
         this.useDesktop   = true;
         this.useEmail     = false;
         this.smtpUsername = null;
         this.smtpPassword = null;
         this.toEmail      = null;
      } else if (config.startsWith("smtp:")) {
         var parts = config.split(":", 4);
         if (parts.length != 4) {
            throw new IllegalArgumentException("Email config must be 'smtp:username:password:toEmail'");
         }
         this.useDesktop   = true;  // Always include desktop
         this.useEmail     = true;
         this.smtpUsername = parts[1];
         this.smtpPassword = parts[2];
         this.toEmail      = parts[3];
      } else {
         throw new IllegalArgumentException("Config must be 'desktop' or 'smtp:username:password:toEmail'");
      }
   }
   
   /**
    * Sends notification via configured channels.
    *
    * @param message The message body
    * @param title Message title
    * @param priority Priority level (0=normal, 1=high)
    */
   void sendNotification(String message, String title, int priority) {
      if (useDesktop) {
         sendDesktopNotification(title, message, priority);
      }
      if (useEmail) {
         sendEmailNotification(title, message, priority);
      }
   }
   
   /**
    * Sends a desktop notification using system tray.
    * Works on Windows, macOS, and Linux with desktop environments.
    */
   private void sendDesktopNotification(String title, String message, int priority) {
      try {
         if (SystemTray.isSupported()) {
            var tray = SystemTray.getSystemTray();
            var image = Toolkit.getDefaultToolkit()
                               .createImage(new byte[0]); // Empty image
            
            var trayIcon = new TrayIcon(image, "Troostwijk Scraper");
            trayIcon.setImageAutoSize(true);
            
            var messageType = priority > 0
                              ? MessageType.WARNING
                              : MessageType.INFO;
            
            tray.add(trayIcon);
            trayIcon.displayMessage(title, message, messageType);
            
            // Remove icon after 2 seconds to avoid clutter
            Thread.sleep(2000);
            tray.remove(trayIcon);
            
            Console.println("Desktop notification sent: " + title);
         } else {
            Console.println("Desktop notifications not supported, logging: " + title + " - " + message);
         }
      } catch (Exception e) {
         System.err.println("Desktop notification failed: " + e.getMessage());
      }
   }
   
   /**
    * Sends email notification via Gmail SMTP (free).
    * Uses Gmail's SMTP server with app password authentication.
    */
   private void sendEmailNotification(String title, String message, int priority) {
      try {
         var props = new Properties();
         props.put("mail.smtp.auth", "true");
         props.put("mail.smtp.starttls.enable", "true");
         props.put("mail.smtp.host", "smtp.gmail.com");
         props.put("mail.smtp.port", "587");
         props.put("mail.smtp.ssl.trust", "smtp.gmail.com");
         
         var session = Session.getInstance(props,
                                           new Authenticator() {
                                              
                                              protected PasswordAuthentication getPasswordAuthentication() {
                                                 return new PasswordAuthentication(smtpUsername, smtpPassword);
                                              }
                                           });
         
         var msg = new MimeMessage(session);
         msg.setFrom(new InternetAddress(smtpUsername));
         msg.setRecipients(RecipientType.TO,
                           InternetAddress.parse(toEmail));
         msg.setSubject("[Troostwijk] " + title);
         msg.setText(message);
         msg.setSentDate(new Date());
         
         if (priority > 0) {
            msg.setHeader("X-Priority", "1");
            msg.setHeader("Importance", "High");
         }
         
         Transport.send(msg);
         Console.println("Email notification sent: " + title);
         
      } catch (Exception e) {
         System.err.println("Email notification failed: " + e.getMessage());
      }
   }
}