/*
 * @(#)VerticalLayouter.java
 *
 * Copyright (c) 1996-2010 by the original authors of JHotDraw and all its
 * contributors. All rights reserved.
 *
 * You may not use, copy or modify this file, except in compliance with the 
 * license agreement you entered into with the copyright holders. For details
 * see accompanying license terms.
 */
package org.jhotdraw.draw.layouter;

import org.jhotdraw.draw.*;
import org.jhotdraw.draw.CompositeFigure;
import java.awt.geom.*;
import org.jhotdraw.geom.*;
import static org.jhotdraw.draw.AttributeKeys.*;

/**
 * A {@link Layouter} which lays out all children of a {@link CompositeFigure}
 * in vertical direction.
 * 

 * The preferred size of the figures is used to determine the layout.
 * This may cause some figures to resize.
 * 

 * The VerticalLayouter honors the LAYOUT_INSETS and the COMPOSITE_ALIGNMENT
 * AttributeKey when laying out a CompositeFigure.
 * 

 * If COMPOSITE_ALIGNMENT is not set on the composite figure, 
 * the layout assigns the same width to all figures.
 * 
 * 
 * @author Werner Randelshofer
 * @version $Id: VerticalLayouter.java 727 2011-01-09 13:23:59Z rawcoder $
 */
public class VerticalLayouter extends AbstractLayouter {

    /**
     * This alignment is used, when 
     */
    private Alignment defaultAlignment = Alignment.BLOCK;

    @Override
    public Rectangle2D.Double calculateLayout(CompositeFigure layoutable, Point2D.Double anchor, Point2D.Double lead) {
        Insets2D.Double layoutInsets = layoutable.get(LAYOUT_INSETS);
        if (layoutInsets == null) {
            layoutInsets = new Insets2D.Double(0, 0, 0, 0);
        }
        Rectangle2D.Double layoutBounds = new Rectangle2D.Double(anchor.x, anchor.y, 0, 0);
        for (Figure child : layoutable.getChildren()) {
            if (child.isVisible()) {
                Dimension2DDouble preferredSize = child.getPreferredSize();
                Insets2D.Double ins = getInsets(child);
                layoutBounds.width = Math.max(layoutBounds.width, preferredSize.width + ins.left + ins.right);
                layoutBounds.height += preferredSize.height + ins.top + ins.bottom;
            }
        }
        layoutBounds.width += layoutInsets.left + layoutInsets.right;
        layoutBounds.height += layoutInsets.top + layoutInsets.bottom;

        return layoutBounds;
    }

    @Override
    public Rectangle2D.Double layout(CompositeFigure layoutable, Point2D.Double anchor, Point2D.Double lead) {
        Insets2D.Double layoutInsets = layoutable.get(LAYOUT_INSETS);
        Alignment compositeAlignment = layoutable.get(COMPOSITE_ALIGNMENT);

        if (layoutInsets == null) {
            layoutInsets = new Insets2D.Double();
        }
        Rectangle2D.Double layoutBounds = calculateLayout(layoutable, anchor, lead);
        double y = layoutBounds.y + layoutInsets.top;
        for (Figure child : layoutable.getChildren()) {
            if (child.isVisible()) {
                Insets2D.Double insets = getInsets(child);
                double height = child.getPreferredSize().height;
                double width = child.getPreferredSize().width;
                switch (compositeAlignment) {
                    case LEADING:
                        child.setBounds(
                                new Point2D.Double(
                                layoutBounds.x + layoutInsets.left + insets.left,
                                y + insets.top),
                                new Point2D.Double(
                                layoutBounds.x + + layoutInsets.left + insets.left + width,
                                y + insets.top + height));
                        break;
                    case TRAILING:
                        child.setBounds(
                                new Point2D.Double(
                                layoutBounds.x + layoutBounds.width - layoutInsets.right - insets.right - width, 
                                y + insets.top),
                                new Point2D.Double(
                                layoutBounds.x + layoutBounds.width - layoutInsets.right - insets.right,
                                y + insets.top + height));
                        break;
                    case CENTER:
                        child.setBounds(
                                new Point2D.Double(
                                layoutBounds.x + (layoutBounds.width - width) / 2d, 
                                y + insets.top),
                                new Point2D.Double(
                                layoutBounds.x + (layoutBounds.width + width) / 2d, 
                                y + insets.top + height));
                        break;
                    case BLOCK:
                    default:
                        child.setBounds(
                                new Point2D.Double(
                                layoutBounds.x + layoutInsets.left + insets.left,
                                y + insets.top),
                                new Point2D.Double(
                                layoutBounds.x + layoutBounds.width - layoutInsets.right - insets.right,
                                y + insets.top + height));
                        break;
                }
                y += height + insets.top + insets.bottom;
            }
        }
        return layoutBounds;
    }
}