package causation.lab;

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

// no custom classes

/**
 * This is a utility Object so that we can get information from the user about
 * what kind of dataset they want to collect in the CausalityLab.
 * Copyright 1999 by David Danks.  All rights reserved.
 *
 * @see	Workbench
 * @version	1.0	June 27, 1999
 * @author	David Danks
 */

public class ExperimentInfoPanel extends JPanel implements ItemListener {

/////////////////// Class Variables ///////////////////
	// how much data will be displayed for an "infinite" sample 
	private static final int INFINITE_SAMPLE_SIZE = 5;

/////////////////// Instance Variables ///////////////////
	private ButtonGroup group;
	private JRadioButton infinite;
	private JRadioButton finite;

	private JTextField sampleSize;
	private JLabel sizeLabel;
	private JTextField sampleName;

/////////////////// Constructors ///////////////////
/**
 * Creates and lays out the JPanel, with it preset to "Finite sample",
 * and with the initial sample name of "experiment".
 */
	public ExperimentInfoPanel() { this("experiment"); }
/**
 * Creates and lays out the JPanel, with it preset to "Finite sample",
 * and with the given initial sample name.
 * @param	initialName	The initial name for the experiment
 */
	public ExperimentInfoPanel(String initialName) {
		sampleSize = new JTextField(6);
		sizeLabel = new JLabel("Sample size (1-5000):");
		sampleName = new JTextField(15);
		sampleName.setText(initialName);

		group = new ButtonGroup();
		infinite = new JRadioButton("Whole population");
		infinite.setSelected(false);
		infinite.addItemListener(this);
		finite = new JRadioButton("Sample");
		finite.setSelected(true);
		finite.addItemListener(this);
		group.add(infinite);
		group.add(finite);
		setInfinite(false);
		
		setLayout(new GridBagLayout());
		
		addComponent(infinite, 0, 0, 1, 1, GridBagConstraints.NONE,
			GridBagConstraints.WEST);
		addComponent(finite, 0, 1, 1, 1, GridBagConstraints.NONE,
			GridBagConstraints.WEST);
		addComponent(sizeLabel, 0, 2, 1, 1, GridBagConstraints.NONE,
			GridBagConstraints.EAST);
		addComponent(sampleSize, 1, 2, 1, 1, GridBagConstraints.NONE,
			GridBagConstraints.WEST);
		addComponent(new JLabel("Sample name:"), 0, 3, 1, 1, 
			GridBagConstraints.NONE, GridBagConstraints.EAST);
		addComponent(sampleName, 1, 3, 1, 1, GridBagConstraints.NONE,
			GridBagConstraints.WEST);
	}

/////////////////// Instance Methods ///////////////////
/**
 * @return	The default infinite sample size, if the user chose that;
 *				0, if the field did not actually contain a number;
 *				otherwise, the number (even if negative)
 */
	public int getSampleSize() {
		if (infinite.isSelected()) return INFINITE_SAMPLE_SIZE;
		int sample;
		try {
			sample = Integer.parseInt(sampleSize.getText()); }
		catch (NumberFormatException n) {
			return 0;
		}
		return sample;
	}
/**
 * @return	Whether the user requested an infinite sample
 */
	public boolean isSampleInfinite() {
		return infinite.isSelected();
	}
/**
 * @return	The sample name
 */
	public String getSampleName() { return sampleName.getText(); }
/**
 * Sets all of the Component.enabled properties correctly when a radio button
 * is clicked
 */
	public void itemStateChanged(ItemEvent e) {
		if (e.getSource() == infinite) setInfinite(true);
		else if (e.getSource() == finite) setInfinite(false);
	}
/**
 * A helper method that sets the Component.enabled properties
 */
	private void setInfinite(boolean b) {
		if (b) {
			sampleSize.setEnabled(false);
			sizeLabel.setEnabled(false);
		}
		else {
			sampleSize.setEnabled(true);
			sizeLabel.setEnabled(true);
		}
	}
/**
 * Puts the focus onto the sample size, so that the user can just type
 */
	public void setCursor() { sampleSize.requestFocus(); }
/**
 * addComponent is a helper method so that we can add lots of components with
 * single-line calls.
 */
	protected void addComponent(Component obj, int posx, int posy, int width,
		int height, int fill, int anchor) {
		GridBagConstraints gbc = new GridBagConstraints();
		gbc.gridx = posx;
		gbc.gridy = posy;
		gbc.gridwidth = width;
		gbc.gridheight = height;
		gbc.fill = fill;
		gbc.anchor = anchor;
		this.add(obj, gbc);
	}

}