package com.nilhcem.fakesmtp.server;
   
   import java.net.InetAddress;
   
   import org.slf4j.Logger;
   import org.slf4j.LoggerFactory;
   import org.subethamail.smtp.helper.SimpleMessageListenerAdapter;
   import org.subethamail.smtp.server.SMTPServer;
   import com.nilhcem.fakesmtp.core.exception.BindPortException;
  import com.nilhcem.fakesmtp.core.exception.OutOfRangePortException;
  
  /**
   * Starts and stops the SMTP server.
   *
   * @author Nilhcem
   * @since 1.0
   */
  public enum SMTPServerHandler {
  	INSTANCE;
  
  	private static final Logger LOGGER = LoggerFactory.getLogger(SMTPServerHandler.class);
  	private final MailSaver mailSaver = new MailSaver();
  	private final MailListener myListener = new MailListener(mailSaver);
  	private final SMTPServer smtpServer = new SMTPServer(new SimpleMessageListenerAdapter(myListener), new SMTPAuthHandlerFactory());
  
  	SMTPServerHandler() {
  	}
  
  	/**
  	 * Starts the server on the port and address specified in parameters.
  	 *
  	 * @param port the SMTP port to be opened.
  	 * @param bindAddress the address to bind to. null means bind to all.
  	 * @throws BindPortException when the port can't be opened.
  	 * @throws OutOfRangePortException when port is out of range.
  	 * @throws IllegalArgumentException when port is out of range.
  	 */
  	public void startServer(int port, InetAddress bindAddress) throws BindPortException, OutOfRangePortException {
  		LOGGER.debug("Starting server on port {}", port);
  		try {
  			smtpServer.setBindAddress(bindAddress);
  			smtpServer.setPort(port);
  			smtpServer.start();
  		} catch (RuntimeException exception) {
  			if (exception.getMessage().contains("BindException")) { // Can't open port
  				LOGGER.error("{}. Port {}", exception.getMessage(), port);
  				throw new BindPortException(exception, port);
  			} else if (exception.getMessage().contains("out of range")) { // Port out of range
  				LOGGER.error("Port {} out of range.", port);
  				throw new OutOfRangePortException(exception, port);
  			} else { // Unknown error
  				LOGGER.error("", exception);
  				throw exception;
  			}
  		}
  	}
  
  	/**
  	 * Stops the server.
  	 * <p>
  	 * If the server is not started, does nothing special.
  	 * </p>
  	 */
  	public void stopServer() {
  		if (smtpServer.isRunning()) {
  			LOGGER.debug("Stopping server");
  			smtpServer.stop();
  		}
  	}
  
  	/**
  	 * Returns the {@code MailSaver} object.
  	 *
  	 * @return the {@code MailSaver} object.
  	 */
  	public MailSaver getMailSaver() {
  		return mailSaver;
  	}
  
  	/**
  	 * Returns the {@code SMTPServer} object.
       *
       * @return the {@code SMTPServer} object.
  	 */
  	public SMTPServer getSmtpServer() {
  		return smtpServer;
  	}
  }