/*
 *    GeoTools - The Open Source Java GIS Toolkit
 *    http://geotools.org
 * 
 *    (C) 2006-2010, Open Source Geospatial Foundation (OSGeo)
 *
 *    This file is hereby placed into the Public Domain. This means anyone is
 *    free to do whatever they wish with this file. Use it well and enjoy!
 */
package org.geotools.render;

import java.awt.Dimension;
import java.awt.Rectangle;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.util.logging.Logger;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.apache.batik.svggen.SVGGeneratorContext;
import org.apache.batik.svggen.SVGGraphics2D;
import org.geotools.geometry.jts.ReferencedEnvelope;
import org.geotools.map.MapContent;
import org.geotools.renderer.lite.StreamingRenderer;
import org.w3c.dom.Document;

/**
 * This is a simple support class which allows you to generate an SVG file from a map.
 * 
 * To use, setup a Map object with the layers you want to render, create an envelope for the region
 * to be drawn and pass in an OutputStream (probably attached to a new file) for the resulting SVG
 * information to be stored in.
 * 
 * Optional you can change the default size of the SVG canvas (in effect increasing the resolution).
 * 
 * @author James Macgill, PennState
 * @version 2.8
 */
public class GenerateSVG {
private static Logger LOGGER = org.geotools.util.logging.Logging
        .getLogger("org.geotools.svgsupport");

// exportSVG start
/**
 * Generate an SVG document from the supplied information. Note, use cavasSize first if you want
 * to change the default output size.
 * 
 * @param map
 *            Contains the layers (features + styles) to be rendered
 * @param env
 *            The portion of the map to generate an SVG from
 * @param out
 *            Stream to write the resulting SVG out to (probable should be a new file)
 * @param canvasSize
 *            optional canvas size, will default to 300x300
 * @throws IOException
 *             Should anything go wrong whilst writing to 'out'
 * @throws ParserConfigurationException
 *             If critical XML tools are missing from the classpath
 */
public static void exportSVG(MapContent map, ReferencedEnvelope env, OutputStream out,
        Dimension canvasSize) throws IOException, ParserConfigurationException {
    if (canvasSize == null) {
        canvasSize = new Dimension(300, 300); // default of 300x300
    }
    Document document = null;
    
    DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
    DocumentBuilder db = dbf.newDocumentBuilder();
    
    // Create an instance of org.w3c.dom.Document
    document = db.getDOMImplementation().createDocument(null, "svg", null);
    
    // Set up the map
    SVGGeneratorContext ctx1 = SVGGeneratorContext.createDefault(document);
    SVGGeneratorContext ctx = ctx1;
    ctx.setComment("Generated by GeoTools2 with Batik SVG Generator");
    
    SVGGraphics2D g2d = new SVGGraphics2D(ctx, true);
    
    g2d.setSVGCanvasSize(canvasSize);
    
    StreamingRenderer renderer = new StreamingRenderer();
    renderer.setMapContent(map);
    
    Rectangle outputArea = new Rectangle(g2d.getSVGCanvasSize());
    ReferencedEnvelope dataArea = map.getMaxBounds();
    
    LOGGER.finest("rendering map");
    renderer.paint(g2d, outputArea, dataArea);
    LOGGER.finest("writing to file");
    OutputStreamWriter osw = null;
    try {
        osw = new OutputStreamWriter(out, "UTF-8");
        g2d.stream(osw);
    } finally {
        if (osw != null)
            osw.close();
    }
    
}
// exportSVG end
}