content: package tim.prune.function.settings;
  
  import java.awt.BorderLayout;
  import java.awt.Component;
  import java.awt.FlowLayout;
  import java.awt.event.KeyAdapter;
  import java.awt.event.KeyEvent;
  import java.io.File;
  
  import javax.swing.BorderFactory;
  import javax.swing.JButton;
  import javax.swing.JCheckBox;
  import javax.swing.JDialog;
  import javax.swing.JFileChooser;
  import javax.swing.JLabel;
  import javax.swing.JOptionPane;
  import javax.swing.JPanel;
  import javax.swing.JTextField;
  import javax.swing.border.EtchedBorder;
  
  import tim.prune.App;
  import tim.prune.DataSubscriber;
  import tim.prune.GenericFunction;
  import tim.prune.I18nManager;
  import tim.prune.UpdateMessageBroker;
  import tim.prune.config.Config;
  import tim.prune.function.cache.ManageCacheFunction;
  
  /**
   * Class to show the popup window for setting the path to disk cache
   */
  public class DiskCacheConfig extends GenericFunction
  {
  	private JDialog _dialog = null;
  	private JCheckBox _cacheCheckbox = null;
  	private JTextField _cacheDirBox = null;
  	private JButton _browseButton = null;
  	private JButton _okButton = null, _manageButton = null;
  	private boolean _initialCheckState = false;
  	private String _initialCacheDir = null;
  
  	/**
  	 * Constructor
  	 * @param inApp app object
  	 */
  	public DiskCacheConfig(App inApp) {
  		super(inApp);
  	}
  
  	/**
  	 * Return the name key for this function
  	 */
  	public String getNameKey() {
  		return "function.diskcache";
  	}
  
  	/**
  	 * @return the contents of the window as a Component
  	 */
  	private Component makeContents()
  	{
  		JPanel dialogPanel = new JPanel();
  		dialogPanel.setBorder(BorderFactory.createCompoundBorder(
  			BorderFactory.createEtchedBorder(EtchedBorder.LOWERED), BorderFactory.createEmptyBorder(4, 4, 4, 4))
  		);
  		dialogPanel.setLayout(new BorderLayout(0, 5));
  		// top panel
  		JPanel topPanel = new JPanel();
  		_cacheCheckbox = new JCheckBox(I18nManager.getText("dialog.diskcache.save"));
  		_cacheCheckbox.addActionListener(e -> enableButtons());
  		topPanel.add(_cacheCheckbox);
  		dialogPanel.add(topPanel, BorderLayout.NORTH);
  		// dir panel
  		JPanel dirPanel = new JPanel();
  		dirPanel.setLayout(new BorderLayout());
  		dirPanel.add(new JLabel(I18nManager.getText("dialog.diskcache.dir") + " : "), BorderLayout.WEST);
  		_cacheDirBox = new JTextField(24);
  		_cacheDirBox.addKeyListener(new KeyAdapter() {
  			public void keyReleased(KeyEvent arg0) {
  				super.keyReleased(arg0);
  				enableButtons();
  			}
  		});
  		dirPanel.add(_cacheDirBox, BorderLayout.CENTER);
  		_browseButton = new JButton(I18nManager.getText("button.browse"));
  		_browseButton.addActionListener(e -> chooseDir());
  		dirPanel.add(_browseButton, BorderLayout.EAST);
  		// holder panel so it doesn't expand vertically
  		JPanel dirHolderPanel = new JPanel();
  		dirHolderPanel.setLayout(new BorderLayout());
  		dirHolderPanel.add(dirPanel, BorderLayout.NORTH);
  		dialogPanel.add(dirHolderPanel, BorderLayout.CENTER);
  
  		// OK, Cancel buttons at the bottom right
  		JPanel buttonPanelr = new JPanel();
  		buttonPanelr.setLayout(new FlowLayout(FlowLayout.RIGHT));
  		_okButton = new JButton(I18nManager.getText("button.ok"));
  		_okButton.addActionListener(e -> {
  			finish();
  			_dialog.dispose();
  		});
  		buttonPanelr.add(_okButton);
  		JButton cancelButton = new JButton(I18nManager.getText("button.cancel"));
  		cancelButton.addActionListener(e -> _dialog.dispose());
  		buttonPanelr.add(cancelButton);
  
  		// Manage button at the bottom left
  		JPanel buttonPanell = new JPanel();
  		buttonPanell.setLayout(new FlowLayout(FlowLayout.LEFT));
  		_manageButton = new JButton(I18nManager.getText("button.manage"));
  		_manageButton.addActionListener(e -> {
  			finish();
  			new ManageCacheFunction(_app).begin();
  		});
  		buttonPanell.add(_manageButton);
  		// Put them together
  		JPanel buttonPanel = new JPanel();
  		buttonPanel.setLayout(new BorderLayout());
  		buttonPanel.add(buttonPanelr, BorderLayout.EAST);
  		buttonPanel.add(buttonPanell, BorderLayout.WEST);
  		dialogPanel.add(buttonPanel, BorderLayout.SOUTH);
  		return dialogPanel;
  	}
  
  	/**
  	 * Enable or disable the buttons according to what's changed
  	 */
  	private void enableButtons()
  	{
  		final boolean checkState = _cacheCheckbox.isSelected();
  		final String path = _cacheDirBox.getText();
  		_cacheDirBox.setEditable(checkState);
  		_browseButton.setEnabled(checkState);
  		boolean ok = false;
  		// If checkbox has stayed off then disable ok
  		if (!_initialCheckState && !checkState) {
  			ok = false;
  		}
  		else
  		{
  			// If checkbox has been switched off then enable
  			ok = true;
  			if (checkState)
  			{
  				// checkbox is on, check value
  				if (path.equals("") || path.equals(_initialCacheDir)) {
  					// Value blank or same as before
  					ok = false;
  				}
  			}
  		}
  		_okButton.setEnabled(ok);
  		// Manage button needs a valid cache
  		boolean cacheDirGood = false;
  		if (checkState && !path.equals(""))
  		{
  			File dir = new File(path);
  			cacheDirGood = dir.exists() && dir.canRead() && dir.isDirectory();
  		}
  		_manageButton.setEnabled(cacheDirGood);
  	}
  
  	/**
  	 * Show window
  	 */
  	public void begin()
  	{
  		if (_dialog == null)
  		{
  			_dialog = new JDialog(_parentFrame, getName());
  			_dialog.setLocationRelativeTo(_parentFrame);
  			_dialog.getContentPane().add(makeContents());
  			_dialog.pack();
  		}
  		// Set controls according to current config
  		final String currPath = getConfig().getConfigString(Config.KEY_DISK_CACHE);
  		_cacheCheckbox.setSelected(currPath != null);
  		_cacheDirBox.setText(currPath==null?"":currPath);
  		_initialCacheDir = currPath;
  		enableButtons();
  		// Remember current state
  		_initialCheckState = _cacheCheckbox.isSelected();
  		_dialog.setVisible(true);
  	}
  
  	/**
  	 * Function activated by the "Browse..." button to select a directory for the cache
  	 */
  	private void chooseDir()
  	{
  		JFileChooser chooser = new JFileChooser();
  		chooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
  		// Set start path from currently selected dir
  		String path = _cacheDirBox.getText();
  		if (path.length() > 1) {
  			chooser.setCurrentDirectory(new File(path));
  		}
  		if (chooser.showOpenDialog(_parentFrame) == JFileChooser.APPROVE_OPTION) {
  			_cacheDirBox.setText(chooser.getSelectedFile().getAbsolutePath());
  		}
  		enableButtons();
  	}
  
  	/**
  	 * OK pressed, save selected settings in Config
  	 */
  	private void finish()
  	{
  		String cachePath = (_cacheCheckbox.isSelected()?_cacheDirBox.getText():null);
  		// Create dir if it doesn't exist already and creation confirmed
  		if (cachePath != null)
  		{
  			File cacheDir = new File(cachePath);
  			if ((!cacheDir.exists() || !cacheDir.isDirectory()) && (JOptionPane.showConfirmDialog(_dialog,
  				I18nManager.getText("dialog.diskcache.createdir") + ": " + cacheDir.getAbsolutePath() + " ?",
  				getName(), JOptionPane.OK_CANCEL_OPTION) == JOptionPane.CANCEL_OPTION || !cacheDir.mkdir()))
  			{
  				JOptionPane.showMessageDialog(_dialog, I18nManager.getText("dialog.diskcache.nocreate"),
  					getName(), JOptionPane.WARNING_MESSAGE);
  				return;
  			}
  			// Check that the cache path is writable too, and give warning if not
  			if (cacheDir.exists() && cacheDir.isDirectory() && !cacheDir.canWrite())
  			{
  				JOptionPane.showMessageDialog(_dialog, I18nManager.getText("dialog.diskcache.cannotwrite"),
  					getName(), JOptionPane.WARNING_MESSAGE);
  			}
  		}
  		getConfig().setConfigString(Config.KEY_DISK_CACHE, cachePath);
  		// inform subscribers so that tiles are wiped from memory and refetched
  		UpdateMessageBroker.informSubscribers(DataSubscriber.MAPSERVER_CHANGED);
  	}
  }
  