/*******************************************************************************
 * Copyright (c) 2004, 2007 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 * Port to the D programming language:
 *     Frank Benoit <benoit@tionex.de>
 *******************************************************************************/
module dwtx.ui.internal.forms.widgets.WrappedPageBook;

import dwt.DWT;
import dwt.graphics.Point;
import dwt.widgets.Composite;
import dwt.widgets.Control;
import dwt.widgets.Layout;
import dwtx.ui.forms.widgets.ILayoutExtension;

import dwt.dwthelper.utils;

/**
 * A pagebook is a composite control where only a single control is visible at
 * a time. It is similar to a notebook, but without tabs.
 * <p>
 * This class may be instantiated; it is not intended to be subclassed.
 * </p>
 */
public class WrappedPageBook : Composite {
    class PageBookLayout : Layout, ILayoutExtension {
        protected Point computeSize(Composite composite, int wHint, int hHint,
                bool flushCache) {
            if (wHint !is DWT.DEFAULT && hHint !is DWT.DEFAULT)
                return new Point(wHint, hHint);
            Point result = null;
            if (currentPage !is null) {
                result = currentPage.computeSize(wHint, hHint, flushCache);
            } else {
                result = new Point(0, 0);
            }
            return result;
        }
        protected void layout(Composite composite, bool flushCache) {
            if (currentPage !is null) {
                currentPage.setBounds(composite.getClientArea());
            }
        }
        /*
         * (non-Javadoc)
         *
         * @see dwtx.ui.forms.widgets.ILayoutExtension#computeMaximumWidth(dwt.widgets.Composite,
         *      bool)
         */
        public int computeMaximumWidth(Composite parent, bool changed) {
            return computeSize(parent, DWT.DEFAULT, DWT.DEFAULT, changed).x;
        }
        /*
         * (non-Javadoc)
         *
         * @see dwtx.ui.forms.widgets.ILayoutExtension#computeMinimumWidth(dwt.widgets.Composite,
         *      bool)
         */
        public int computeMinimumWidth(Composite parent, bool changed) {
            return computeSize(parent, 0, DWT.DEFAULT, changed).x;
        }
    }
    /**
     * The current control; <code>null</code> if none.
     */
    private Control currentPage = null;
    /**
     * Creates a new empty pagebook.
     *
     * @param parent
     *            the parent composite
     * @param style
     *            the DWT style bits
     */
    public this(Composite parent, int style) {
        super(parent, style);
        setLayout(new PageBookLayout());
    }
    /**
     * Shows the given page. This method has no effect if the given page is not
     * contained in this pagebook.
     *
     * @param page
     *            the page to show
     */
    public void showPage(Control page) {
        if (page is currentPage)
            return;
        if (page.getParent() !is this)
            return;
        Control oldPage = currentPage;
        currentPage = page;
        // show new page
        if (page !is null) {
            if (!page.isDisposed()) {
                //page.setVisible(true);
                layout(true);
                page.setVisible(true);
            }
        }
        // hide old *after* new page has been made visible in order to avoid
        // flashing
        if (oldPage !is null && !oldPage.isDisposed())
            oldPage.setVisible(false);
    }
    public Point computeSize(int wHint, int hHint, bool changed) {
        return (cast(PageBookLayout) getLayout()).computeSize(this, wHint, hHint,
                changed);
    }
}