fop/src/org/apache/fop/svg/SVGElement.java

/*
 * $Id$
 * Copyright (C) 2001 The Apache Software Foundation. All rights reserved.
 * For details on use and redistribution please refer to the
 * LICENSE file included with these sources.
 */

package org.apache.fop.svg;

// FOP
import org.apache.fop.fo.*;
import org.apache.fop.fo.properties.*;
import org.apache.fop.layout.FontState;
import org.apache.fop.apps.FOPException;

import org.apache.batik.dom.svg.*;
import org.apache.batik.dom.util.XMLSupport;
import org.w3c.dom.*;
import org.w3c.dom.svg.*;
import org.w3c.dom.svg.SVGLength;
import org.xml.sax.Attributes;
import org.apache.batik.bridge.*;
import org.apache.batik.swing.svg.*;
import org.apache.batik.swing.gvt.*;
import org.apache.batik.gvt.*;
import org.apache.batik.gvt.renderer.*;
import org.apache.batik.gvt.filter.*;
import org.apache.batik.gvt.event.*;
import org.apache.batik.bridge.UnitProcessor;
import org.apache.batik.util.SVGConstants;

import org.w3c.dom.DOMImplementation;
import org.w3c.dom.css.CSSPrimitiveValue;

import org.apache.batik.dom.svg.SVGDOMImplementation;

import java.io.File;
import java.net.URL;
import java.util.List;
import java.util.ArrayList;
import java.awt.geom.AffineTransform;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.awt.Dimension;

/**
 * class representing svg:svg pseudo flow object.
 */
public class SVGElement extends SVGObj {

    /**
     * constructs an SVG object (called by Maker).
     *
     * @param parent the parent formatting object
     * @param propertyList the explicit properties of this object
     */
    public SVGElement(FONode parent) {
        super(parent);
    }

    public void handleAttrs(Attributes attlist) throws FOPException {
        super.handleAttrs(attlist);
        init();
    }

    public Point2D getDimension(final Point2D view) {

        // TODO - change so doesn't hold onto fo,area tree
        Element svgRoot = element;
        /* create an SVG area */
        /* if width and height are zero, get the bounds of the content. */

        try {
            String baseDir = userAgent.getBaseURL();
            if(baseDir != null) {
                ((SVGOMDocument)doc).setURLObject(new URL(baseDir));
            }
        } catch (Exception e) {
            getLogger().error("Could not set base URL for svg", e);
        }

        Element e = ((SVGDocument)doc).getRootElement();
        final float ptmm = userAgent.getPixelToMM();
        SVGContext dc = new SVGContext() {
            public float getPixelToMM() {
                return ptmm;
            }
            public float getPixelUnitToMillimeter() {
                return ptmm;
            }

            public Rectangle2D getBBox() {
                return new Rectangle2D.Double(0, 0, view.getX(), view.getY());
            }

            public AffineTransform getCTM() {
                return new AffineTransform();
            }

            public AffineTransform getGlobalTransform() {
                return new AffineTransform();
            }

            public float getViewportWidth() {
                return (float)view.getX();
            }

            public float getViewportHeight() {
                return (float)view.getY();
            }

            public float getFontSize(){
                return 12;
            }
        };
        ((SVGOMElement)e).setSVGContext(dc);

        //if(!e.hasAttributeNS(XMLSupport.XMLNS_NAMESPACE_URI, "xmlns")) {
            e.setAttributeNS(XMLSupport.XMLNS_NAMESPACE_URI, "xmlns", SVGDOMImplementation.SVG_NAMESPACE_URI);
        //}

        Point2D p2d = getSize(12 /* font size */, svgRoot, userAgent.getPixelToMM());
       ((SVGOMElement)e).setSVGContext(null);

        return p2d;
    }

    private void init() {
        DOMImplementation impl = SVGDOMImplementation.getDOMImplementation();
        String svgNS = SVGDOMImplementation.SVG_NAMESPACE_URI;
        doc = impl.createDocument(svgNS, "svg", null);

        element = doc.getDocumentElement();

        buildTopLevel(doc, element);
    }

    public static Point2D getSize(int size, Element svgRoot, float ptmm) {
        String str;
        UnitProcessor.Context ctx;
        ctx = new PDFUnitContext(size, svgRoot, ptmm);
        str = svgRoot.getAttributeNS(null, SVGConstants.SVG_WIDTH_ATTRIBUTE);
        if (str.length() == 0) str = "100%";
        float width = UnitProcessor.svgHorizontalLengthToUserSpace
            (str, SVGConstants.SVG_WIDTH_ATTRIBUTE, ctx);

        str = svgRoot.getAttributeNS(null, SVGConstants.SVG_HEIGHT_ATTRIBUTE);
        if (str.length() == 0) str = "100%";
        float height = UnitProcessor.svgVerticalLengthToUserSpace
            (str, SVGConstants.SVG_HEIGHT_ATTRIBUTE, ctx);
        return new Point2D.Float(width, height);
    }
    /**
     * This class is the default context for a particular
     * element. Informations not available on the element are get from
     * the bridge context (such as the viewport or the pixel to
     * millimeter factor.
     */
    public static class PDFUnitContext implements UnitProcessor.Context {

        /** The element. */
        protected Element e;
        protected int fontSize;
        float pixeltoMM;

        public PDFUnitContext(int size, Element e, float ptmm) {
            this.e  = e;
            this.fontSize = size;
        }

        /**
         * Returns the element.
         */
        public Element getElement() {
            return e;
        }

        /**
      * Returns the context of the parent element of this context.
         * Since this is always for the root SVG element there never
         * should be one...
         */
        public UnitProcessor.Context getParentElementContext() {
            return null;
        }

        /**
         * Returns the pixel to mm factor.
         */
        public float getPixelToMM() {
            return pixeltoMM;
        }
        public float getPixelUnitToMillimeter() {
            return pixeltoMM;
        }

        /**
         * Returns the font-size medium value in pt.
         */
        public float getMediumFontSize() {
            return 9f;
        }

        /**
         * Returns the font-size value.
         */
        public float getFontSize() {
            return fontSize;
        }

        /**
         * Returns the x-height value.
         */
        public float getXHeight() {
            return 0.5f;
        }

        /**
         * Returns the viewport width used to compute units.
         */
        public float getViewportWidth() {
            return 100;
        }

        /**
         * Returns the viewport height used to compute units.
         */
        public float getViewportHeight() {
            return 100;
        }
    }
}