package causation.lab;

// packages
import javax.swing.*;
import javax.swing.plaf.*;
import java.awt.*;
import java.awt.geom.*;

// custom classes
import causation.lab.WorkbenchObject;
import causation.lab.plaf.LatentUI;

/**
 * <p>
 * This class encodes the Latent variables for the CausalityLab.  For now,
 * they cannot have values, so they are just graphical objects, and 
 * nodes in a directed graph.
 * </p><p>
 * The following <code>PropertyChangeEvent</code>s are created by this
 * class:
 *	<ul>
 * <li>("name", String oldName, String newName)
 *	<ul><li>Values always different</ul>
 * </li></p><p>
 * NOTE: It would be nice if this class actually used tetrad.graph.Node as
 * a model, since it would better integrate the CausalityLab with Tetrad
 * IV.  However, this code was written before Tetrad IV was started, and
 * it would be more trouble than it would be worth to fix things right
 * now.
 * </p><p>
 * Copyright 1999 by David Danks.  All rights reserved.
 * </p>
 *
 * @see	WorkbenchObject
 * @see	LatentUI
 * @version	0.9	June 28, 1999
 * @author	David Danks
 */

public class Latent extends WorkbenchObject {

/////////////////// Class Variables ///////////////////
	private static final String UIClassID = "causation.lab.plaf.LatentUI";
	private static final Font font = new Font("Serif", Font.ITALIC, 14);
	private static final Insets MARGIN = new Insets(3, 10, 3, 10);

/////////////////// Instance Variables ///////////////////
	private String name;
	private boolean selected = false;
	private boolean experimenting = false;
	private boolean highlight = false;
	private Ellipse2D.Double ellipse = null;
	private Dimension size = null;

/////////////////// Constructors ///////////////////
/**
 * Creates a Latent named "default"
 */
	public Latent() { this("default"); }
/**
 * Creates a Latent with the given name
 * @param	name	The name of the Latent
 */
	public Latent(String name) {
		this.name = name;
		setFont(font);
		updateParameters();
		updateUI();
	}

/////////////////// Instance Methods ///////////////////
/**
 * @return	The name of the Latent
 */
	public String getName() { return name; }
/**
 * @param	newName	The new name of the Latent
 */
	public void setName(String newName) {
		if (newName == null) newName = "";
		if (newName.equals(name)) return;
		String oldName = name;
		updateParameters();
		firePropertyChange("name", oldName, name);
	}
/**
 * @return	Whether the Workbench with the Latent is "experimenting".
 */
	public boolean isExperimenting() { return experimenting; }
/**
 * @param	b	Whether the Workbench with the Latent is "experimenting".
 */
	public void setExperimenting(boolean b) { experimenting = b; }
/**
 * @return	Whether the Latent is currently highlighted
 */
	public boolean isHighlight() { return highlight; }
/**
 * @param	b	Whether the Latent should be highlighted
 */
	public void setHighlight(boolean b) { highlight = b; }
/**
 * @return	The preferred size of the Latent
 */
	public Dimension getPreferredSize() { return size; }
/**
 * @return	The minimum size of the Latent (currently the preferred size)
 */
	public Dimension getMinimumSize() { return size; }
/**
 * @return	<code>false</code> always, since we want transparency
 */
	public boolean isOpaque() { return false; }
	
/**
 * @return	The ellipse that bounds the Latent
 */
	public Ellipse2D getEllipse() { return ellipse; }
/**
 * Implemented since we are subclassing WorkbenchObject
 * @return	The bounding Shape for the Latent (an Ellipse2D.Double)
 */
	public Shape getPerimeter() { 
		Ellipse2D.Double shift = new 
			Ellipse2D.Double(ellipse.getX()+getBounds().x,
				ellipse.getY()+getBounds().y, ellipse.getWidth(), 
				ellipse.getHeight());
		return (Shape)shift; 
	}
/**
 * @return	The Point of the lower left corner of the (centered) text 
 */
	public Point getTextOrigin() { 
		return new Point(MARGIN.left, 
			MARGIN.top+getFontMetrics(getFont()).getAscent());
	}
/**
 * A helper method that determines the size of the ellipse
 */
	private void updateParameters() {
		// first, determine the size of the text box
		FontMetrics fm = getFontMetrics(getFont());
		int intHeight = fm.getHeight();
		int intWidth = fm.stringWidth(name);
		// take the margin into account
		intHeight += (MARGIN.top + MARGIN.bottom);
		intWidth += (MARGIN.left + MARGIN.right);
		size = new Dimension(intWidth+1, intHeight+1);
		
		// now, create the ellipse
		ellipse = new Ellipse2D.Double(0.0, 0.0, (double)intWidth, 
			(double)intHeight);
	}
	
// UI methods
/**
 * @param	ui	The LatentUI to attach to this Latent
 */
	public void setUI(LatentUI ui) { super.setUI(ui); }
/**
 * Sets up the UI appropriately
 */
	public void updateUI() {
		setUI((LatentUI)UIManager.getUI(this));
		invalidate();
	}
/**
 * @return	The String identifying the UI for this Class
 */
	public String getUIClassID() { return UIClassID; }

}