/*
 * MultiInputPane.java - a utility class for displaying a dialog that
 * asks for multiple values.  Based on ideas in Wu's javabook.MultiInputBox
 * class and javax.swing.JOptionPane
 *
 * Copyright (c) 2004 - Russell C. Bjork
 */

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;

public class MultiInputPane extends JOptionPane
{
	/** Pop up a dialog asking for multiple items of input
	 *
	 *	@param parentComponent the parent Component of the dialog that is shown
	 *	@param prompts the prompts to display
	 *	@param initialValues the initial values to display for each item -
	 *		   this parameter can be null, in which case no initial values
	 *		   are specified; or individual elements can be null,
	 *		   indicating that no initial value is specified for a particular
	 *		   field
	 *	@param title the title for this dialog
	 *	@return an array of values corresponding to the various prompts,
	 *			or null if the user cancelled
	 */
	public static String [] showMultiInputDialog(Component parentComponent,
												 String [] prompts,
												 String [] initialValues,
												 String title)
	{
		MultiInputPane pane = new MultiInputPane(prompts, initialValues);
		JDialog dialog = pane.createDialog(parentComponent, 
									       title != null ? title : "MultiInputPane");		
		dialog.pack();
		dialog.show();
		
		if (! pane.ok)
			return null;
			
		String [] results = new String [prompts.length];
		for (int i = 0; i < prompts.length; i ++)
			results[i] = pane.fields[i].getText();
			
		return results;
	}

	/** Pop up a dialog asking for multiple items of input
	 *
	 *	@param parentComponent the parent Component of the dialog that is shown
	 *	@param prompts the prompts to display
	 *	@param title the title for this dialog
	 *	@return an array of values corresponding to the various prompts,
	 *			or null if the user cancelled
	 */
	public static String [] showMultiInputDialog(Component parentComponent,
												 String [] prompts,
												 String title)
	{
		return showMultiInputDialog(parentComponent, prompts, null, title);
	}
	
	/** Pop up a dialog asking for multiple items of input
	 *
	 *	@param parentComponent the parent Component of the dialog that is shown
	 *	@param prompts the prompts to display
	 *	@param initialValues the initial values to display for each item -
	 *		   this parameter can be null, in which case no initial values
	 *		   are specified; or individual elements can be null,
	 *		   indicating that no initial value is specified for a particular
	 *		   field
	 *	@return an array of values corresponding to the various prompts,
	 *			or null if the user cancelled
	 */
	public static String [] showMultiInputDialog(Component parentComponent,
												 String [] prompts,
												 String [] initialValues)
	{
		return showMultiInputDialog(parentComponent, prompts, initialValues, null);
	}
	
	/** Pop up a dialog asking for multiple items of input
	 *
	 *	@param parentComponent the parent Component of the dialog that is shown
	 *	@param prompts the prompts to display
	 *	@return an array of values corresponding to the various prompts,
	 *			or null if the user cancelled
	 */
	public static String [] showMultiInputDialog(Component parentComponent,
												 String [] prompts)
	{
		return showMultiInputDialog(parentComponent, prompts, null, null);
	}
	
	/** Constructor used by the above
	 *
	 *	@param prompts the prompts to display
	 *	@param initialValues the initial values to display for each item -
	 *		   this parameter can be null, in which case no initial values
	 *		   are specified; or individual elements can be null,
	 *		   indicating that no initial value is specified for a particular
	 *		   field
	 */
	private MultiInputPane(String [] prompts, String [] initialValues)
	{
		super();
		removeAll();
		
		setLayout(new GridLayout(prompts.length + 1, 2, 5, 5));
		fields = new JTextField[prompts.length];
		
		for (int i = 0; i < prompts.length; i ++)
		{
			add(new JLabel(prompts[i]));
			fields[i] = new JTextField();
			add(fields[i]);
			if (initialValues != null && initialValues[i] != null)
				fields[i].setText(initialValues[i]);
		}
		
		JPanel okPanel = new JPanel();
		JButton okButton = new JButton("OK");
		okPanel.add(okButton);
		add(okPanel);
		JPanel cancelPanel = new JPanel();
		JButton cancelButton = new JButton("Cancel");
		cancelPanel.add(cancelButton);
		add(cancelPanel);
		
		okButton.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e)
			{
				ok = true;
				getTopLevelAncestor().setVisible(false);
			}
		});
		
		cancelButton.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e)
			{
				getTopLevelAncestor().setVisible(false);
			}
		});
		
	}
	
	
	// Test driver
	
	public static void main(String [] args)
	{
		String [] prompts = { "A", "B", "C" };
		String [] initialValues = { "a", null, "c" };
		String [] results = showMultiInputDialog(null, prompts, initialValues, "Test");
		if (results == null)
			System.out.println("Null result");
		else
			for (int i = 0; i < results.length; i ++)
				System.out.println("Result " + i + " = " + results[i]);
		System.exit(0);
	}
	
	private JTextField [] fields;
	private boolean ok;
}