LoginPanel.java

package games.strategy.engine.lobby.client.login;

import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.Window;
import java.awt.event.KeyEvent;
import java.util.logging.Logger;
import java.util.prefs.BackingStoreException;
import java.util.prefs.Preferences;

import javax.swing.Action;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JComponent;
import javax.swing.JDialog;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
import javax.swing.KeyStroke;
import javax.swing.SwingUtilities;

import games.strategy.engine.lobby.server.userDB.DBUserController;
import games.strategy.ui.SwingAction;
import games.strategy.ui.Util;

public class LoginPanel extends JPanel {
  private static final long serialVersionUID = -1115199161238394717L;
  private static final Logger s_logger = Logger.getLogger(LoginPanel.class.getName());

  public static enum ReturnValue {
    CANCEL, LOGON, CREATE_ACCOUNT
  }

  public static final String LAST_LOGIN_NAME_PREF = "LAST_LOGIN_NAME_PREF";
  public static final String ANONYMOUS_LOGIN_PREF = "ANONYMOUS_LOGIN_PREF";
  private JDialog m_dialog;
  private JPasswordField m_password;
  private JTextField m_userName;
  private JCheckBox m_anonymous;
  private JButton m_createAccount;
  private ReturnValue m_returnValue;
  private JButton m_logon;
  private JButton m_cancel;

  public LoginPanel() {
    createComponents();
    layoutComponents();
    setupListeners();
    readDefaults();
    setWidgetActivation();
  }

  private void readDefaults() {
    final Preferences prefs = Preferences.userNodeForPackage(this.getClass());
    final String name = prefs.get(LAST_LOGIN_NAME_PREF, System.getProperty("user.name"));
    final boolean anonymous = prefs.getBoolean(ANONYMOUS_LOGIN_PREF, true);
    m_anonymous.setSelected(anonymous);
    m_userName.setText(name);
    SwingUtilities.invokeLater(() -> {
      if (!m_anonymous.isSelected()) {
        m_password.requestFocusInWindow();
      } else {
        m_userName.requestFocusInWindow();
      }
    });
  }

  private void createComponents() {
    m_password = new JPasswordField();
    m_userName = new JTextField();
    m_anonymous = new JCheckBox("Login Anonymously?");
    m_createAccount = new JButton("Create Account...");
    m_logon = new JButton("Login");
    m_cancel = new JButton("Cancel");
  }

  private void layoutComponents() {
    final JLabel label = new JLabel(new ImageIcon(Util.getBanner("Login")));
    setLayout(new BorderLayout());
    add(label, BorderLayout.NORTH);
    final JPanel main = new JPanel();
    add(main, BorderLayout.CENTER);
    main.setLayout(new GridBagLayout());
    main.add(new JLabel("Username:"), new GridBagConstraints(0, 0, 1, 1, 0, 0, GridBagConstraints.EAST,
        GridBagConstraints.NONE, new Insets(10, 20, 0, 0), 0, 0));
    main.add(m_userName, new GridBagConstraints(1, 0, 1, 1, 0, 0, GridBagConstraints.EAST, GridBagConstraints.BOTH,
        new Insets(10, 5, 0, 40), 0, 0));
    main.add(new JLabel("Password:"), new GridBagConstraints(0, 1, 1, 1, 0, 0, GridBagConstraints.EAST,
        GridBagConstraints.NONE, new Insets(5, 20, 0, 0), 0, 0));
    main.add(m_password, new GridBagConstraints(1, 1, 1, 1, 0, 0, GridBagConstraints.EAST, GridBagConstraints.BOTH,
        new Insets(5, 5, 0, 40), 0, 0));
    main.add(m_anonymous, new GridBagConstraints(0, 2, 2, 1, 1, 1, GridBagConstraints.WEST, GridBagConstraints.NONE,
        new Insets(5, 20, 0, 0), 0, 0));
    main.add(m_createAccount, new GridBagConstraints(0, 3, 2, 1, 0, 0, GridBagConstraints.WEST, GridBagConstraints.NONE,
        new Insets(5, 20, 0, 0), 0, 0));
    final JPanel buttons = new JPanel();
    buttons.setLayout(new FlowLayout(FlowLayout.RIGHT));
    buttons.add(m_logon);
    buttons.add(m_cancel);
    add(buttons, BorderLayout.SOUTH);
  }

  private void setupListeners() {
    m_logon.addActionListener(e -> logonPressed());
    m_createAccount.addActionListener(e -> {
      m_returnValue = ReturnValue.CREATE_ACCOUNT;
      m_dialog.setVisible(false);
    });
    m_cancel.addActionListener(e -> m_dialog.setVisible(false));
    m_anonymous.addActionListener(e -> setWidgetActivation());
    // close when hitting the escape key
    final Action enterAction = SwingAction.of(e -> logonPressed());
    final String key = "logon.through.enter.key";
    getActionMap().put(key, enterAction);
    getActionMap().put(key, enterAction);
    getInputMap(JComponent.WHEN_IN_FOCUSED_WINDOW).put(KeyStroke.getKeyStroke(KeyEvent.VK_ENTER, 0), key);
  }

  private void logonPressed() {
    final String userName = m_userName.getText();
    final boolean anonymous = m_anonymous.isSelected();
    if (DBUserController.validateUserName(userName) != null) {
      JOptionPane.showMessageDialog(this, DBUserController.validateUserName(userName), "Invalid Username",
          JOptionPane.ERROR_MESSAGE);
      return;
    } else if (m_password.getPassword().length == 0 && !anonymous) {
      JOptionPane.showMessageDialog(LoginPanel.this, "You must enter a password", "No Password",
          JOptionPane.ERROR_MESSAGE);
      return;
    } else if (m_password.getPassword().length < 3 && !anonymous) {
      JOptionPane.showMessageDialog(LoginPanel.this, "Passwords must be at least three characters long",
          "Invalid password", JOptionPane.ERROR_MESSAGE);
      return;
    }
    m_returnValue = ReturnValue.LOGON;
    m_dialog.setVisible(false);
  }

  public static void storePrefs(final String userName, final boolean anonymous) {
    final Preferences prefs = Preferences.userNodeForPackage(LoginPanel.class);
    prefs.put(LAST_LOGIN_NAME_PREF, userName);
    prefs.putBoolean(ANONYMOUS_LOGIN_PREF, anonymous);
    try {
      prefs.flush();
    } catch (final BackingStoreException e) {
      // not a big deal
      s_logger.warning(e.getMessage());
    }
  }

  private void setWidgetActivation() {
    if (!m_anonymous.isSelected()) {
      m_password.setEnabled(true);
      m_password.setBackground(m_userName.getBackground());
    } else {
      m_password.setEnabled(false);
      m_password.setBackground(this.getBackground());
    }
  }

  public boolean isAnonymous() {
    return m_anonymous.isSelected();
  }

  public String getUserName() {
    return m_userName.getText();
  }

  public String getPassword() {
    return new String(m_password.getPassword());
  }

  public ReturnValue show(final Window parent) {
    m_dialog = new JDialog(JOptionPane.getFrameForComponent(parent), "Login", true);
    m_dialog.getContentPane().add(this);
    m_dialog.pack();
    m_dialog.setLocationRelativeTo(parent);
    m_dialog.setVisible(true);
    m_dialog.dispose();
    m_dialog = null;
    if (m_returnValue == null) {
      return ReturnValue.CANCEL;
    }
    return m_returnValue;
  }
}