package com.nilhcem.fakesmtp.gui.info;
   
   import java.awt.event.ActionEvent;
   import java.awt.event.ActionListener;
   import java.util.Observable;
   import java.util.Observer;
   
   import javax.swing.JButton;
   import javax.swing.JOptionPane;
  
  import com.nilhcem.fakesmtp.core.Configuration;
  import com.nilhcem.fakesmtp.core.I18n;
  import com.nilhcem.fakesmtp.core.exception.BindPortException;
  import com.nilhcem.fakesmtp.core.exception.InvalidPortException;
  import com.nilhcem.fakesmtp.core.exception.OutOfRangePortException;
  import com.nilhcem.fakesmtp.model.UIModel;
  
  /**
   * Button to start the SMTP server.
   *
   * @author Nilhcem
   * @since 1.0
   */
  public final class StartServerButton extends Observable implements Observer {
  	private final I18n i18n = I18n.INSTANCE;
  
  	private final JButton button = new JButton(i18n.get("startsrv.start"));
  
  	/**
  	 * Creates a start button to start the SMTP server.
  	 * <p>
  	 * If the user selects a wrong port before starting the server, the method will display an error message.
  	 * </p>
  	 */
  	public StartServerButton() {
  		button.addActionListener(new ActionListener() {
  			@Override
  			public void actionPerformed(ActionEvent e) {
  				toggleButton();
  			}
  		});
  	}
  
  	/**
  	 * Switches the text inside the button and calls the PortTextField observer to enable/disable the port field.
  	 *
  	 * @see PortTextField
  	 */
  	public void toggleButton() {
  		try {
  			UIModel.INSTANCE.toggleButton();
  		} catch (InvalidPortException ipe) {
  			displayError(String.format(i18n.get("startsrv.err.invalid")));
  		} catch (BindPortException bpe) {
  			displayError(String.format(i18n.get("startsrv.err.bound"), bpe.getPort()));
  		} catch (OutOfRangePortException orpe) {
  			displayError(String.format(i18n.get("startsrv.err.range"), orpe.getPort()));
  		} catch (RuntimeException re) {
  			displayError(String.format(i18n.get("startsrv.err.default"), re.getMessage()));
  		}
  
  		if (UIModel.INSTANCE.isStarted()) {
  			button.setText(i18n.get("startsrv.started"));
  			button.setEnabled(false);
  		}
  		setChanged();
  		notifyObservers();
  	}
  
  	/**
  	 * Returns the JButton object.
  	 *
  	 * @return the JButton object.
  	 */
  	public JButton get() {
  		return button;
  	}
  
  	/**
  	 * Displays a message dialog displaying the error specified in parameter.
  	 *
  	 * @param error a string representing the error which will be displayed in a message dialog.
  	 */
  	private void displayError(String error) {
  		JOptionPane.showMessageDialog(button.getParent(), error,
  			String.format(i18n.get("startsrv.err.title"), Configuration.INSTANCE.get("application.name")),
  			JOptionPane.ERROR_MESSAGE);
  	}
  
  	@Override
  	public void update(Observable o, Object arg) {
  		if (o instanceof PortTextField) {
  			toggleButton();
  		}
  	}
  }