/*******************************************************************************
 * Copyright (c) 2000, 2005 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
 *******************************************************************************/
package org.eclipse.draw2d;

import org.eclipse.draw2d.geometry.Dimension;
import org.eclipse.draw2d.geometry.Rectangle;

/**
 * A viewport for {@link org.eclipse.draw2d.FreeformFigure FreeformFigures}.  
 * FreeformFigures can only reside in this type of viewport.
 */
public class FreeformViewport
	extends Viewport
{

class FreeformViewportLayout
	extends ViewportLayout
{
	protected Dimension calculatePreferredSize(IFigure parent, int wHint, int hHint) {
		getContents().validate();
		wHint = Math.max(0, wHint);
		hHint = Math.max(0, hHint);
		return ((FreeformFigure)getContents())
			.getFreeformExtent()
			.getExpanded(getInsets())
			.union(0, 0)
			.union(wHint - 1, hHint - 1)
			.getSize();
	}

	protected boolean isSensitiveHorizontally(IFigure parent) {
		return true;
	}

	protected boolean isSensitiveVertically(IFigure parent) {
		return true;
	}


	public void layout(IFigure figure) {
		//Do nothing, contents updates itself.
	}
}

/**
 * Constructs a new FreeformViewport.  This viewport must use graphics translation to 
 * scroll the FreeformFigures inside of it.
 */
public FreeformViewport() {
	super(true); //Must use graphics translate to scroll freeforms.
	setLayoutManager(new FreeformViewportLayout());
}

/**
 * Readjusts the scrollbars.  In doing so, it gets the freeform extent of the contents and
 * unions this rectangle with this viewport's client area, then sets the contents freeform
 * bounds to be this unioned rectangle.  Then proceeds to set the scrollbar values based
 * on this new information.
 * @see Viewport#readjustScrollBars()
 */
protected void readjustScrollBars() {
	if (getContents() == null)
		return;
	if (!(getContents() instanceof FreeformFigure))
		return;
	FreeformFigure ff = (FreeformFigure)getContents();
	Rectangle clientArea = getClientArea();
	Rectangle bounds = ff.getFreeformExtent().getCopy();
	bounds.union(0, 0, clientArea.width, clientArea.height);
	ff.setFreeformBounds(bounds);

	getVerticalRangeModel().setAll(bounds.y, clientArea.height, bounds.bottom());
	getHorizontalRangeModel().setAll(bounds.x, clientArea.width, bounds.right());
}

/**
 * Returns <code>true</code>.
 * @see Figure#useLocalCoordinates()
 */
protected boolean useLocalCoordinates() {
	return true;
}

}