/*
Copyright 2008-2011 Gephi
Authors : Mathieu Bastian <mathieu.bastian@gephi.org>
Website : http://www.gephi.org

This file is part of Gephi.

DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

Copyright 2011 Gephi Consortium. All rights reserved.

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or /cddl-1.0.txt and /gpl-3.0.txt. See the License for the
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 */
package org.gephi.perspective.api;

import org.gephi.perspective.spi.Perspective;

/**
 * Controller to manage the perspective system. A perspective is a set of panels
 * in the user interface. 'Overview', 'Data Laboratory' and 'Preview' are the
 * default perspectives.
 * <p>
 * The default perspective implementations can be found in the 'Desktop Perspective'
 * module.
 * <p>
 * The property <b>org.gephi.perspective.default</b> can be added at startup to change the default starting perspective:
 * <ul><li>org.gephi.perspective.default=OverviewGroup</li>
 * <li>org.gephi.perspective.default=LaboratoryGroup</li>
 * <li>org.gephi.perspective.default=PreviewGroup</li></ul>
 * 
 * @see Perspective
 * @author Mathieu Bastian
 */
public interface PerspectiveController {

    /**
     * Returns the selected perspective or <code>null</code> if no perspective
     * is selected. By default the 'Overview' perspective is selected.
     * @return the currently selected perspective or <code>null</code>
     */
    public Perspective getSelectedPerspective();

    /**
     * Returns all perspectives installed. This is equivalent to
     * <code>Lookup.getDefault().lookupAll(Perspective.class)</code>.
     * @return all installed perspectives
     */
    public Perspective[] getPerspectives();

    /**
     * Switch the current perspective to the given perspective. Only one perspective
     * can be selected at a time.
     * @param perspective the perspective to select
     */
    public void selectPerspective(Perspective perspective);
}
