/*
 * ConfigView.java
 * 
 * Copyright (c) 2003-2004 Digi International
 * This program and the information contained in it is confidential and
 * proprietary to Digi International and may not be used, copied, or re-
 * produced without the prior written permission of Digi International.
 * 
 */

package com.digi.config.ui;

import com.digi.config.core.*;

import javax.swing.*;
import java.awt.Component;
import java.net.*;
import java.util.*;

/** 
 * This interface defines the basic operations required for all configuration views
 * that are used in the configuration application.
 */


public interface ConfigView { 
    /**
     * Returns a one word name identifying this view. 
     */
    public String getName();

    /** 
     * Return the Component that displays the primary content for this view
     */
    public Component getViewContent();

    /** 
     * Returns the Component that displays the heading of the view.
     * If this view has no heading to display this method returns null.
     */
    public Component getViewHeading();

    /** 
     * Returns the Component that displays the buttons below the view.
     * If this view has no buttons to display this method returns null.
     */
    public Component getViewButtons();

    /**
     * Returns a resource key to the help information for this view. The actual
     * URL will be looked up in the Help Resource bundle.
     */
    public String getHelpResource();



    /**
     * Informs view what device to work with. View should flush any
     * cached device data and mark current view content as invalid
     * so that it is refreshed appropriatly.
     */
    public void setDevice(Device device);

    /**
     * This method is called to instruct the view that it is about to be made
     * active. When a view is active it needs to make sure its content is correct.
     * An example of why a panel may be inactive is if it were on a tabbed pane 
     * and was not currently visible or if the user selected some other view.
     */
    public void activate();

    /**
     * This method is called to instruct the view that it is about to be made
     * inactive. When a view is inactive, it does not need to worry
     * about maintaining its content in a correct state. An example of why a panel
     * may be inactive is if it were on a tabbed pane and was not currently visible
     * or if the user selected some other view.
     */
    public void deactivate();

    /**
     * Indicates if any changes have been made by the user that have not yet been
     * saved to the device(ie committed).
     */
    public boolean isChanged();

    /**
     * This method instructs the view to validate any of the changes the user has made
     * within the view. Any errors are to be added to the provided errorList. 
     * 
     * @param errorList is a collection of ViewValidationError objects
     */
    public void validateChanges(Collection errorList);

    /**
     * This method instructs the view to place any changes the user has made within 
     * the view into the provided clusters. Once the changes have been saved to
     * to the device, a subsequent call to commitChanges() will be made.
     */
    public void getChanges(KvpNode settingCluster, KvpNode stateCluster);

    /**
     * Instructs the view to consider any user changes within the view as 
     * saved to the device (ie committed).
     */
    public void commitChanges();

    /** 
     * Instructs the view to discard any changes the user has made within the
     * view and revert those fields to the original state. The view is also 
     * free to refresh all its fields to the present cached state of the device at 
     * this time.
     */
    public void cancelChanges();

}