package com.nilhcem.fakesmtp.gui.info;
   
   import com.nilhcem.fakesmtp.core.Configuration;
   import com.nilhcem.fakesmtp.core.I18n;
   import com.nilhcem.fakesmtp.model.UIModel;
   
   import javax.swing.JTextField;
   import javax.swing.event.DocumentEvent;
   import javax.swing.event.DocumentListener;
  import java.awt.event.ActionEvent;
  import java.awt.event.ActionListener;
  import java.util.Observable;
  import java.util.Observer;
  
  /**
   * Text field in which will be written the desired SMTP port.
   *
   * @author Nilhcem
   * @since 1.0
   */
  public final class PortTextField extends Observable implements Observer {
  
  	private final JTextField portTextField = new JTextField();
  
  	/**
  	 * Creates the port field object and adds a listener on change to alert the presentation model.
  	 * <p>
  	 * The default port's value is defined in the configuration.properties file.<br>
  	 * Each time the port is modified, the port from the {@link UIModel} will be reset.
  	 * </p>
  	 */
  	public PortTextField() {
  		portTextField.setToolTipText(I18n.INSTANCE.get("porttextfield.tooltip"));
  		portTextField.getDocument().addDocumentListener(new DocumentListener() {
  			@Override
  			public void removeUpdate(DocumentEvent e) {
  				warn();
  			}
  
  			@Override
  			public void insertUpdate(DocumentEvent e) {
  				warn();
  			}
  
  			@Override
  			public void changedUpdate(DocumentEvent e) {
  				warn();
  			}
  
  			private void warn() {
  				UIModel.INSTANCE.setPort(portTextField.getText());
  			}
  		});
  
  		portTextField.setText(Configuration.INSTANCE.get("smtp.default.port"));
  		portTextField.addActionListener(new ActionListener() {
  			@Override
  			public void actionPerformed(ActionEvent e) {
  				setChanged();
  				notifyObservers();
  			}
  		});
  	}
  
  	/**
  	 * Returns the JTextField object.
  	 *
  	 * @return the JTextField object.
  	 */
  	public JTextField get() {
  		return portTextField;
  	}
  
  	/**
  	 * Sets the specified port in the text field only if this latter is not {@code null}.
  	 *
  	 * @param portStr the port to set.
  	 */
  	public void setText(String portStr) {
  		if (portStr != null && !portStr.isEmpty()) {
  			portTextField.setText(portStr);
  		}
  	}
  
  	/**
  	 * Enables or disables the port text field.
  	 * <p>
  	 * When the element will receive an action from the {@link StartServerButton} object,
  	 * it will enable or disable the port, so that the user can't modify it
  	 * when the server is already launched.
  	 * </p>
  	 *
  	 * @param o the observable element which will notify this class.
  	 * @param arg optional parameters (not used).
  	 */
  	@Override
  	public void update(Observable o, Object arg) {
  		if (o instanceof StartServerButton) {
  			portTextField.setEnabled(!UIModel.INSTANCE.isStarted());
 		}
 	}
 }