/*

* Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

* All rights reserved.

* This component and the accompanying materials are made available

* under the terms of "Eclipse Public License v1.0"

* which accompanies this distribution, and is available

* at the URL "http://www.eclipse.org/legal/epl-v10.html".

*

* Initial Contributors:

* Nokia Corporation - initial contribution.

*

* Contributors:

*

* Description:

*

*/

package javax.microedition.lcdui;

import org.eclipse.swt.internal.extension.CompositeExtension;

import org.eclipse.swt.internal.qt.graphics.GraphicsContext;

import org.eclipse.swt.widgets.Control;

import org.eclipse.swt.widgets.Internal_PackageSupport;

import org.eclipse.swt.widgets.Widget;

import org.eclipse.swt.internal.qt.graphics.WindowSurface;

final class CanvasBufferLinux extends Buffer {

	private Canvas host;

	private WindowSurface surface;

	private boolean syncPaintCallback;

	private int paintX, paintY;

	private int paintW, paintH;

	CanvasBufferLinux(Canvas canvas, Control ctrl)

	{

        super();

        setControlBounds(ctrl);

        host = canvas;

	}

	void bindToHost(GraphicsContext gc) 

	{

		gc.bindTarget(surface);

	}

    void ensureWindowSurface() 

    {

    	if(surface == null)

    	{

    		surface = Internal_PackageSupport.getWindowsurface(host.getShell());

    	}

    }

	void beginPaint(int x, int y, int w, int h) 

	{

		ensureWindowSurface();

		paintX = x; 

		paintY = y;

		paintW = w;

		paintH = h;

		surface.beginPaint(paintX, paintY, paintW, paintH);

	}

	void endPaint() 

	{

	    // nothing to do	

	}

	void blit(GraphicsContext gc, Widget widget) 

	{

		// On linux platform this method is called in order to 

		// request new paint event and also from the actual paint event itself to blit the

		// frame to display.

		// The behavior of this method depends on the syncpaintCallback flag, which 

		// indicates on which above scenario we are in each time.

		// If we are within the paint callback

		// draw the window surface to display

		if(syncPaintCallback) 

		{

			gc.drawWindowSurface(surface, paintX, paintX, paintW, paintH);

		}

		else

		{	

			// We are requesting a paint event

			syncPaintCallback = true;

			((CompositeExtension)widget).redrawNow(paintX, paintY, paintW, paintH);

			syncPaintCallback = false;

			// Once the display has been updated, 

			// clear the invalidate area

			paintX = paintY = paintW = paintH = 0; 

		}

	}

	Object getHost() 

	{	

		return host;

	}

	int getHostType() 

	{

		return HOST_TYPE_CANVAS;

	}

	boolean isPaintingActive() {

		return syncPaintCallback;

	}

	WindowSurface getWindowSurface()

    {

        return surface;

    }

}