/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/* $Id$ */

package org.apache.fop.render.afp;

import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.geom.AffineTransform;
import java.io.IOException;

import org.w3c.dom.Document;

import org.apache.batik.bridge.BridgeContext;
import org.apache.batik.bridge.GVTBuilder;
import org.apache.batik.gvt.GraphicsNode;

import org.apache.xmlgraphics.image.loader.Image;
import org.apache.xmlgraphics.image.loader.ImageFlavor;
import org.apache.xmlgraphics.image.loader.impl.ImageXMLDOM;
import org.apache.xmlgraphics.java2d.Graphics2DImagePainter;

import org.apache.fop.afp.AFPDataObjectInfo;
import org.apache.fop.afp.AFPGraphics2D;
import org.apache.fop.afp.AFPGraphicsObjectInfo;
import org.apache.fop.afp.AFPObjectAreaInfo;
import org.apache.fop.afp.AFPPaintingState;
import org.apache.fop.afp.AFPResourceInfo;
import org.apache.fop.afp.AFPResourceLevelDefaults;
import org.apache.fop.afp.AFPResourceManager;
import org.apache.fop.apps.FOUserAgent;
import org.apache.fop.image.loader.batik.BatikImageFlavors;
import org.apache.fop.image.loader.batik.BatikUtil;
import org.apache.fop.image.loader.batik.Graphics2DImagePainterImpl;
import org.apache.fop.render.ImageHandler;
import org.apache.fop.render.ImageHandlerUtil;
import org.apache.fop.render.RenderingContext;
import org.apache.fop.svg.SVGEventProducer;

/**
 * Image handler implementation which handles SVG images for AFP output.
 * <p>
 * Note: This class is not intended to be used as an {@link AFPImageHandler} but only as an
 * {@link ImageHandler}. It subclasses {@link AFPImageHandler} only to get access to common
 * methods.
 */
public class AFPImageHandlerSVG implements ImageHandler {

    private static final ImageFlavor[] FLAVORS = new ImageFlavor[] {
        BatikImageFlavors.SVG_DOM
    };

    /** @return a new AFP data object info instance */
    protected AFPDataObjectInfo createDataObjectInfo() {
        return new AFPGraphicsObjectInfo();
    }

    /** {@inheritDoc} */
    public void handleImage(RenderingContext context, Image image, Rectangle pos)
                throws IOException {
        AFPRenderingContext afpContext = (AFPRenderingContext)context;
        ImageXMLDOM imageSVG = (ImageXMLDOM)image;
        FOUserAgent userAgent = afpContext.getUserAgent();

        AFPDataObjectInfo info = createDataObjectInfo();
        assert (info instanceof AFPGraphicsObjectInfo);
        AFPGraphicsObjectInfo graphicsObjectInfo = (AFPGraphicsObjectInfo) info;
        graphicsObjectInfo.setCreatePageSegment(afpContext.getPaintingState().getWrapGocaPSeg());
        AFPResourceInfo resourceInfo = graphicsObjectInfo.getResourceInfo();
        resourceInfo.setUri(imageSVG.getInfo().getOriginalURI());
        setDefaultToInlineResourceLevel(graphicsObjectInfo, afpContext.getResourceManager());

        // Create a new AFPGraphics2D
        AFPPaintingState paintingState = afpContext.getPaintingState();
        final boolean textAsShapes = paintingState.isStrokeGOCAText();
        AFPGraphics2D g2d = new AFPGraphics2D(
                textAsShapes,
                afpContext.getPaintingState(),
                afpContext.getResourceManager(),
                resourceInfo,
                (textAsShapes ? null : afpContext.getFontInfo()));
        g2d.setGraphicContext(new org.apache.xmlgraphics.java2d.GraphicContext());

        paintingState.setImageUri(image.getInfo().getOriginalURI());

        // Create an AFPBridgeContext
        BridgeContext bridgeContext = AFPSVGHandler.createBridgeContext(userAgent, g2d);

        // Cloning SVG DOM as Batik attaches non-thread-safe facilities (like the CSS engine)
        // to it.
        Document clonedDoc = BatikUtil.cloneSVGDocument(imageSVG.getDocument());

        // Build the SVG DOM and provide the painter with it
        GraphicsNode root;
        try {
            GVTBuilder builder = new GVTBuilder();
            root = builder.build(bridgeContext, clonedDoc);
        } catch (Exception e) {
            SVGEventProducer eventProducer = SVGEventProducer.Provider.get(
                    context.getUserAgent().getEventBroadcaster());
            eventProducer.svgNotBuilt(this, e, image.getInfo().getOriginalURI());
            return;
        }

        // Image positioning
        AFPObjectAreaInfo objectAreaInfo = AFPImageHandler.createObjectAreaInfo(paintingState, pos);
        graphicsObjectInfo.setObjectAreaInfo(objectAreaInfo);

        paintingState.save(); // save
        AffineTransform placement = new AffineTransform();
        placement.translate(pos.x, pos.y);
        paintingState.concatenate(placement);

        //Set up painter and target
        graphicsObjectInfo.setGraphics2D(g2d);
        // Create Graphics2DImagePainter
        Dimension imageSize = image.getSize().getDimensionMpt();
        Graphics2DImagePainter painter = new Graphics2DImagePainterImpl(
                root, bridgeContext, imageSize);
        graphicsObjectInfo.setPainter(painter);

        // Create the GOCA GraphicsObject in the DataStream
        AFPResourceManager resourceManager = afpContext.getResourceManager();
        resourceManager.createObject(graphicsObjectInfo);

        paintingState.restore(); // resume
    }

    private void setDefaultToInlineResourceLevel(AFPGraphicsObjectInfo graphicsObjectInfo,
                                                 AFPResourceManager resourceManager) {
        AFPResourceInfo resourceInfo = graphicsObjectInfo.getResourceInfo();
        if (!resourceInfo.levelChanged()) {
            resourceInfo.setLevel(resourceManager.getResourceLevelDefaults()
                    .getDefaultResourceLevel(AFPResourceLevelDefaults.TYPE_SVG));
        }
    }

    /** {@inheritDoc} */
    public int getPriority() {
        return 400;
    }

    /** {@inheritDoc} */
    public Class getSupportedImageClass() {
        return ImageXMLDOM.class;
    }

    /** {@inheritDoc} */
    public ImageFlavor[] getSupportedImageFlavors() {
        return FLAVORS;
    }

    /** {@inheritDoc} */
    public boolean isCompatible(RenderingContext targetContext, Image image) {
        boolean supported = (image == null || (image instanceof ImageXMLDOM
                && image.getFlavor().isCompatible(BatikImageFlavors.SVG_DOM)))
                && targetContext instanceof AFPRenderingContext;
        if (supported) {
            AFPRenderingContext afpContext = (AFPRenderingContext)targetContext;
            if (!afpContext.getPaintingState().isGOCAEnabled()) {
                return false;
            }
            String mode = (String)targetContext.getHint(ImageHandlerUtil.CONVERSION_MODE);
            if (ImageHandlerUtil.isConversionModeBitmap(mode)) {
                //Disabling this image handler automatically causes a bitmap to be generated
                return false;
            }
        }
        return supported;
    }

}
