/*

     dsh-graph-io  Directed graph readers and writers.

     Copyright (c) 2008-2013 held jointly by the individual authors.

     This library is free software; you can redistribute it and/or modify it

     under the terms of the GNU Lesser General Public License as published

     by the Free Software Foundation; either version 3 of the License, or (at

     your option) any later version.

     This library is distributed in the hope that it will be useful, but WITHOUT

     ANY WARRANTY; with out even the implied warranty of MERCHANTABILITY or

     FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public

     License for more details.

     You should have received a copy of the GNU Lesser General Public License

     along with this library;  if not, write to the Free Software Foundation,

     Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA.

     > http://www.fsf.org/licensing/licenses/lgpl.html

     > http://www.opensource.org/licenses/lgpl-license.php

 */

 package org.dishevelled.graph.io.ygraphml;

 import java.io.File;

 import java.io.FileWriter;

 import java.io.IOException;

 import java.io.OutputStream;

 import java.text.DecimalFormat;

 import java.text.NumberFormat;

 import java.util.HashMap;

 import java.util.Map;

 import javax.xml.stream.XMLOutputFactory;

 import javax.xml.stream.XMLStreamException;

 import javax.xml.stream.XMLStreamWriter;

 import org.dishevelled.graph.Edge;

 import org.dishevelled.graph.Graph;

 import org.dishevelled.graph.Node;

 import org.dishevelled.graph.io.GraphWriter;

 /**

  * Graph writer for the yFiles extension to GraphML.

  *

  * @author  Michael Heuer

  * @version $Revision$ $Date$

  */

 public final class YGraphMLWriter

     implements GraphWriter<ShapeNode, PolyLineEdge>

 {

     /** XML output factory. */

     private final XMLOutputFactory outputFactory;

     /**

      * Create a new YGraphML writer.

      */

     public YGraphMLWriter()

     {

         outputFactory = XMLOutputFactory.newInstance();

     }

     /** {@inheritDoc} */

     public void write(final Graph<ShapeNode, PolyLineEdge> graph, final File file)

         throws IOException

     {

         if (graph == null)

         {

             throw new IllegalArgumentException("graph must not be null");

         }

         if (file == null)

         {

             throw new IllegalArgumentException("file must not be null");

         }

         try

         {

             XMLStreamWriter writer = outputFactory.createXMLStreamWriter(new FileWriter(file));

             write(graph, writer);

         }

         catch (XMLStreamException e)

         {

             //throw new IOException(e); jdk1.6+

             throw new IOException(e.getMessage());

         }

     }

     /** {@inheritDoc} */

     public void write(final Graph<ShapeNode, PolyLineEdge> graph, final OutputStream outputStream)

         throws IOException

     {

         if (graph == null)

         {

             throw new IllegalArgumentException("graph must not be null");

         }

         if (outputStream == null)

         {

             throw new IllegalArgumentException("outputStream must not be null");

         }

         try

         {

             XMLStreamWriter writer = outputFactory.createXMLStreamWriter(outputStream);

             write(graph, writer);

         }

         catch (XMLStreamException e)

         {

             //throw new IOException(e); jdk 1.6+

             throw new IOException(e.getMessage());

         }

     }

     /**

      * Write the specified graph to the specified XML stream writer.

      *

      * @param graph graph to write

      * @param writer XML stream writer to write to

      * @throws IOException if an error occurs

      * @throws XMLStreamException if an error occurs

      */

     private void write(final Graph<ShapeNode, PolyLineEdge> graph, final XMLStreamWriter writer)

         throws IOException, XMLStreamException

     {

         writer.writeStartDocument("1.0");

         //writer.writeStartDocument("UTF-8", "1.0");

         writer.writeStartElement("graphml");

         writer.writeDefaultNamespace("http://graphml.graphdrawing.org/xmlns");

         writer.writeNamespace("xsi", "http://www.w3.org/2001/XMLSchema-instance");

         writer.writeNamespace("y", "http://www.yworks.com/xml/graphml");

         writer.writeAttribute("xsi:schemaLocation", "http://graphml.graphdrawing.org/xmlns/graphml http://www.yworks.com/xml/schema/graphml/1.0/ygraphml.xsd");

         writer.writeStartElement("key");

         writer.writeAttribute("id", "k0");

         writer.writeAttribute("for", "node");

         writer.writeAttribute("yfiles.type", "nodegraphics");

         writer.writeEndElement(); // </key>

         writer.writeStartElement("key");

         writer.writeAttribute("id", "k1");

         writer.writeAttribute("for", "edge");

         writer.writeAttribute("yfiles.type", "edgegraphics");

         writer.writeEndElement(); // </key>

         writer.writeStartElement("graph");

         writer.writeAttribute("id", "G");

         writer.writeAttribute("edgedefault", "directed");

         NumberFormat numberFormat = NumberFormat.getInstance();

         if (numberFormat instanceof DecimalFormat)

         {

             ((DecimalFormat) numberFormat).setMinimumFractionDigits(1);

         }

         int n = 0;

         Map<Node<ShapeNode, PolyLineEdge>, String> nodeIds = new HashMap<Node<ShapeNode, PolyLineEdge>, String>(graph.nodeCount());

         for (Node<ShapeNode, PolyLineEdge> node : graph.nodes())

         {

             String nodeId = nodeIds.get(node);

             if (nodeId == null)

             {

                 nodeId = "n" + n;

                 n++;

                 nodeIds.put(node, nodeId);

             }

             writer.writeStartElement("node");

             writer.writeAttribute("id", nodeId);

             writer.writeStartElement("data");

             writer.writeAttribute("key", "k0");

             ShapeNode shapeNode = node.getValue();

             writer.writeStartElement("http://www.yworks.com/xml/graphml", "ShapeNode");

             Fill fill = shapeNode.getFill();

             writer.writeStartElement("http://www.yworks.com/xml/graphml", "Fill");

             writer.writeAttribute("color", fill.getColor());

             writer.writeAttribute("transparent", fill.isTransparent() ? "true" : "false");

             writer.writeEndElement(); // <y:Fill>

             BorderStyle borderStyle = shapeNode.getBorderStyle();

             writer.writeStartElement("http://www.yworks.com/xml/graphml", "BorderStyle");

             writer.writeAttribute("type", borderStyle.getType());

             writer.writeAttribute("width", numberFormat.format(borderStyle.getWidth()));

             writer.writeAttribute("color", borderStyle.getColor());

             writer.writeEndElement(); // <y:BorderStyle>

             NodeLabel nodeLabel = shapeNode.getNodeLabel();

             writer.writeStartElement("http://www.yworks.com/xml/graphml", "NodeLabel");

             writer.writeAttribute("visible", nodeLabel.isVisible() ? "true" : "false");

             writer.writeAttribute("alignment", nodeLabel.getAlignment());

             writer.writeAttribute("fontFamily", nodeLabel.getFontFamily());

             writer.writeAttribute("fontSize", String.valueOf(nodeLabel.getFontSize()));

             writer.writeAttribute("fontStyle", nodeLabel.getFontStyle());

             writer.writeAttribute("textColor", nodeLabel.getTextColor());

             writer.writeAttribute("modelName", nodeLabel.getModelName());

             writer.writeAttribute("modelPosition", nodeLabel.getModelPosition());

             writer.writeAttribute("autoSizePolicy", nodeLabel.getAutoSizePolicy());

             writer.writeCharacters(nodeLabel.getText());

             writer.writeEndElement(); // <y:NodeLabel>

             Shape shape = shapeNode.getShape();

             writer.writeStartElement("http://www.yworks.com/xml/graphml", "Shape");

             writer.writeAttribute("type", shape.getType());

             writer.writeEndElement(); // <y:Shape>

             writer.writeEndElement(); // <y:ShapeNode>

             writer.writeEndElement(); // </data>

             writer.writeEndElement(); // </node>

         }

         int e = 0;

         for (Edge<ShapeNode, PolyLineEdge> edge : graph.edges())

         {

             String edgeId = "e" + e;

             e++;

             writer.writeStartElement("edge");

             writer.writeAttribute("id", edgeId);

             writer.writeAttribute("source", nodeIds.get(edge.source()));

             writer.writeAttribute("target", nodeIds.get(edge.target()));

             writer.writeStartElement("data");

             writer.writeAttribute("key", "k1");

             PolyLineEdge polyLineEdge = edge.getValue();

             writer.writeStartElement("http://www.yworks.com/xml/graphml", "PolyLineEdge");

             LineStyle lineStyle = polyLineEdge.getLineStyle();

             writer.writeStartElement("http://www.yworks.com/xml/graphml", "LineStyle");

             writer.writeAttribute("type", lineStyle.getType());

             writer.writeAttribute("width", numberFormat.format(lineStyle.getWidth()));

             writer.writeAttribute("color", lineStyle.getColor());

             writer.writeEndElement(); // <y:LineStyle>

             Arrows arrows = polyLineEdge.getArrows();

             writer.writeStartElement("http://www.yworks.com/xml/graphml", "Arrows");

             writer.writeAttribute("source", arrows.getSource());

             writer.writeAttribute("target", arrows.getTarget());

             writer.writeEndElement(); // <y:Arrows>

             EdgeLabel edgeLabel = polyLineEdge.getEdgeLabel();

             writer.writeStartElement("http://www.yworks.com/xml/graphml", "EdgeLabel");

             writer.writeAttribute("visible", edgeLabel.isVisible() ? "true" : "false");

             writer.writeAttribute("alignment", edgeLabel.getAlignment());

             writer.writeAttribute("fontFamily", edgeLabel.getFontFamily());

             writer.writeAttribute("fontSize", String.valueOf(edgeLabel.getFontSize()));

             writer.writeAttribute("fontStyle", edgeLabel.getFontStyle());

             writer.writeAttribute("textColor", edgeLabel.getTextColor());

             writer.writeAttribute("modelName", edgeLabel.getModelName());

             writer.writeAttribute("modelPosition", edgeLabel.getModelPosition());

             writer.writeAttribute("preferredPlacement", edgeLabel.getPreferredPlacement());

             writer.writeAttribute("distance", numberFormat.format(edgeLabel.getDistance()));

             writer.writeAttribute("ratio", numberFormat.format(edgeLabel.getRatio()));

             writer.writeCharacters(edgeLabel.getText());

             writer.writeEndElement(); // <y:EdgeLabel>

             BendStyle bendStyle = polyLineEdge.getBendStyle();

             writer.writeStartElement("http://www.yworks.com/xml/graphml", "BendStyle");

             writer.writeAttribute("smoothed", bendStyle.isSmoothed() ? "true" : "false");

             writer.writeEndElement(); // <y:BendStyle>

             writer.writeEndElement(); // <y:PolyLineEdge>

             writer.writeEndElement(); // </data>

             writer.writeEndElement(); // </edge>

         }

         writer.writeEndElement(); // </graph>

         writer.writeEndElement(); // </graphml>

         writer.close();

    }

 }