package com.onaro.util.jfc.wizard;

import java.awt.Component;
import java.beans.PropertyChangeListener;
import java.net.URL;

/**
 * A step in a multi step data entry wizard. A step is a three part dialog providing
 * a description, data entry and buttons.
 * <p>
 * The step implementation should issue <code>ProperyChangeEvenet</code> whenever
 * the data entered becomes valid or invalid. Doing so will allow the wizard to
 * control the buttons.
 */
public interface WizardStep {

	/**
	 * Property name for listening to step validity state changes.
	 */
	public static final String PROPERTY_VALID = "valid"; //$NON-NLS-1$

	/**
	 * Gets the title of this step.
	 *
	 * @return this step's title
	 */
	public String getTitle();

	/**
	 * Gets a URL to an <b>HTML</b> file containing the description of this step.
	 *
	 * @return a URL to the HTML description file or <code>null</code> if not
     *         exists.
	 */
	public URL getDescriptionUrl() ;


        public Component getDescriptionComponent();

	/**
	 * Gets the data entry component.
	 *
	 * @return the component displaying the data entry for this step
	 */
	public Component getDataEntry();

	/**
	 * Tests if the data entered in this step is valid.
	 *
	 * @return true if the data entered is valid and the wizard can proceed to
	 *         the next step or finish
	 */
	public boolean isValid();

	/**
	 * Gets the next step after this one.
	 *
	 * @return the next <code>WizardStep</code> or null if this is the last
	 */
	public WizardStep getNext();

	/**
	 * Adds a property change listener for this step.
	 *
	 * @param l the listener
	 */
	public void addPropertyChangeListener(PropertyChangeListener l);

	/**
	 * Removes a property change listener from this step.
	 *
	 * @param l the listener
	 */
	public void removePropertyChangeListener(PropertyChangeListener l);

	/**
	 * notify the wizard step to stop the editing in its component
	 *
	 */
	public void stopEditing();
}