package org.simantics.modeling;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.RenderingHints;
import java.awt.RenderingHints.Key;
import java.awt.geom.AffineTransform;
import java.awt.geom.Rectangle2D;
import java.io.ByteArrayOutputStream;
import java.io.OutputStreamWriter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.List;
import java.util.Map;
import java.util.Random;
import java.util.Set;
import java.util.UUID;
import java.util.function.Function;
import java.util.stream.Collectors;

import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;

import org.apache.batik.dom.GenericDOMImplementation;
import org.apache.batik.svggen.SVGGeneratorContext;
import org.apache.batik.svggen.SVGGraphics2D;
import org.simantics.Simantics;
import org.simantics.datatypes.literal.GUID;
import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.common.request.IndexRoot;
import org.simantics.db.common.request.ResourceRead;
import org.simantics.db.common.request.UnaryRead;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.exception.RuntimeDatabaseException;
import org.simantics.db.layer0.variable.Variables;
import org.simantics.diagram.elements.DecorationSVGNode;
import org.simantics.diagram.elements.DiagramNodeUtil;
import org.simantics.diagram.elements.TextGridNode;
import org.simantics.diagram.elements.TextNode;
import org.simantics.diagram.stubs.DiagramResource;
import org.simantics.g2d.canvas.Hints;
import org.simantics.g2d.canvas.ICanvasContext;
import org.simantics.g2d.diagram.DiagramHints;
import org.simantics.g2d.diagram.IDiagram;
import org.simantics.g2d.diagram.handler.DataElementMap;
import org.simantics.g2d.diagram.participant.Selection;
import org.simantics.g2d.element.IElement;
import org.simantics.g2d.scenegraph.ICanvasSceneGraphProvider;
import org.simantics.g2d.utils.CanvasUtils;
import org.simantics.layer0.Layer0;
import org.simantics.scenegraph.INode;
import org.simantics.scenegraph.ParentNode;
import org.simantics.scenegraph.g2d.G2DParentNode;
import org.simantics.scenegraph.g2d.G2DRenderingHints;
import org.simantics.scenegraph.g2d.G2DSceneGraph;
import org.simantics.scenegraph.g2d.IG2DNode;
import org.simantics.scenegraph.g2d.IG2DNodeVisitor;
import org.simantics.scenegraph.g2d.events.command.Commands;
import org.simantics.scenegraph.g2d.nodes.BackgroundNode;
import org.simantics.scenegraph.g2d.nodes.BoundsNode;
import org.simantics.scenegraph.g2d.nodes.ConnectionNode;
import org.simantics.scenegraph.g2d.nodes.DataNode;
import org.simantics.scenegraph.g2d.nodes.NavigationNode;
import org.simantics.scenegraph.g2d.nodes.SVGNode;
import org.simantics.scenegraph.g2d.nodes.SelectionNode;
import org.simantics.scenegraph.g2d.nodes.SingleElementNode;
import org.simantics.scenegraph.g2d.nodes.connection.RouteGraphNode;
import org.simantics.scenegraph.g2d.nodes.spatial.RTreeNode;
import org.simantics.scenegraph.utils.NodeUtil;
import org.simantics.scl.runtime.function.Function1;
import org.simantics.scl.runtime.tuple.Tuple2;
import org.simantics.trend.impl.ItemNode;
import org.simantics.utils.threads.ThreadUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.w3c.dom.DOMImplementation;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

public class SCLScenegraph {

	private static final Logger LOGGER = LoggerFactory.getLogger(SCLScenegraph.class);
	
	private static final String MAIN_SECTION = "main";
	private static final String SELECTION_SECTION = "selection";
	private static final String SELECTION_MASK_SECTION = "selectionMask";
	
	private static final String[] ALL_SECTIONS = { MAIN_SECTION, SELECTION_SECTION, SELECTION_MASK_SECTION };

	@Deprecated
	public static ICanvasSceneGraphProvider getICanvasSceneGraphProvider(Resource model, Resource diagram, String diagramRVI) throws DatabaseException, InterruptedException {
		ICanvasSceneGraphProvider provider = DiagramNodeUtil.loadSceneGraphProvider(model, diagram, diagramRVI);
		return provider;
	}
	
	@Deprecated
	public static void disposeSceneGraphProvider(ICanvasSceneGraphProvider provider) {
		provider.dispose();
	}

    public static <T> T doWithICanvasSceneGraphProvider(Resource diagram, Function1<ICanvasSceneGraphProvider, T> func) throws DatabaseException {
        return doWithICanvasSceneGraphProvider(diagram, (Function<ICanvasSceneGraphProvider, T>) provider -> func.apply(provider));
    }

    public static <T> T doWithICanvasSceneGraphProvider(Resource diagram, Function<ICanvasSceneGraphProvider, T> func) throws DatabaseException {
        Tuple2 result = Simantics.getSession().syncRequest(new ResourceRead<Tuple2>(diagram) {

            @Override
            public Tuple2 perform(ReadGraph graph) throws DatabaseException {
                Resource indexRoot = graph.syncRequest(new IndexRoot(resource));
                String diagramRVI = Variables.getRVI(graph, resource);
                return new Tuple2(indexRoot, diagramRVI);
            }
        });
        ICanvasSceneGraphProvider provider = DiagramNodeUtil.loadSceneGraphProvider((Resource) result.c0, diagram, (String) result.c1);
        try {
            return func.apply(provider);
        } finally {
            provider.dispose();
        }
    }

    public static <T> T doWithCanvasContext(Resource diagram, Function1<ICanvasContext, T> func) throws DatabaseException {
        return doWithCanvasContext(diagram, (Function<ICanvasContext, T>) canvasContext -> func.apply(canvasContext));
    }

    public static <T> T doWithCanvasContext(Resource diagram, Function<ICanvasContext, T> func) throws DatabaseException {
        return doWithICanvasSceneGraphProvider(diagram, (Function<ICanvasSceneGraphProvider, T>) provider -> func.apply(provider.getCanvasContext()));
    }

	public static String getNodeTransform(ICanvasContext ctx, String name) {
		
		Set<TextNode> texts = NodeUtil.collectNodes(ctx.getSceneGraph(), TextNode.class);
		for (TextNode text : texts) {
			String nodeName = NodeUtil.getNodeName(text);
			if (nodeName.equals(name)) {
				String transform = text.getTransform().toString();
				return transform;
			}
		}
		return "No node found";
	}
	
	public static String getNodeText(ICanvasContext ctx, String name) {
		
		Set<TextNode> texts = NodeUtil.collectNodes(ctx.getSceneGraph(), TextNode.class);
		for (TextNode text : texts) {
			String nodeName = NodeUtil.getNodeName(text);
			if (nodeName.equals(name)) {
				String texti = text.getText();
				return texti;
			}
		}
		return "No node found";
	}
	
	public static String getNodeCount(ICanvasContext ctx) {
		G2DSceneGraph g2 = ctx.getSceneGraph();
		int amount = NodeUtil.countTreeNodes(g2);
		return "Node count: " + amount;
	}
	
    public static String getAllNodes (ICanvasContext ctx) {
    	
    	Set<G2DSceneGraph> g2 = NodeUtil.collectNodes(ctx.getSceneGraph(), G2DSceneGraph.class);
    	int amount = g2.size() +1;
    	return "All nodes: " + amount;
    }
    
    public static String getBoundsNodes (ICanvasContext ctx) {
    	
    	Set<BoundsNode> bn = NodeUtil.collectNodes(ctx.getSceneGraph(), BoundsNode.class);
    	int amount = bn.size();
    	return "BoundsNodes: " + amount;
    }
    
    public static String getBackgroundNodes (ICanvasContext ctx) {
    	
    	Set<BackgroundNode> bg = NodeUtil.collectNodes(ctx.getSceneGraph(), BackgroundNode.class);
    	int amount = bg.size();
    	return "BackgroundNodes: " + amount;
    }
    
    public static String getDataNodes (ICanvasContext ctx) {
    	
    	Set<DataNode> dn = NodeUtil.collectNodes(ctx.getSceneGraph(), DataNode.class);
    	int amount = dn.size();
    	return "DataNodes: " + amount;
    }
    
    public static String getNavigationNodes (ICanvasContext ctx) {
    	
    	Set<NavigationNode> g2 = NodeUtil.collectNodes(ctx.getSceneGraph(), NavigationNode.class);
    	int amount = g2.size();
    	return "NavigationNodes: " + amount;
    }
    
    public static String getParentNodes (ICanvasContext ctx) {
    	
    	Set<G2DParentNode> g2 = NodeUtil.collectNodes(ctx.getSceneGraph(), G2DParentNode.class);
    	int amount = g2.size();
    	return "ParentNodes: " + amount;
    }
    
    public static String getDecorationNodes (ICanvasContext ctx) {
    	
    	Set<DecorationSVGNode> deco = NodeUtil.collectNodes(ctx.getSceneGraph(), DecorationSVGNode.class);
    	int amount = deco.size();
    	return "DecorationNodes: " + amount;
    }
    
    public static String getSingleElementNodes (ICanvasContext ctx) {
    	
    	Set<SingleElementNode> g2 = NodeUtil.collectNodes(ctx.getSceneGraph(), SingleElementNode.class);
    	int amount = g2.size();
    	return "SingleElementNodes: " + amount;
    }
    
    public static String getConnectionNodes (ICanvasContext ctx) {
    	
    	Set<ConnectionNode> g2 = NodeUtil.collectNodes(ctx.getSceneGraph(), ConnectionNode.class);
    	int amount = g2.size();
    	return "ConnectionNodes: " + amount;
    }
    
    public static String getTextNodes (ICanvasContext ctx) {
    	
    	Set<TextNode> tn = NodeUtil.collectNodes(ctx.getSceneGraph(), TextNode.class);
    	Set<TextGridNode> tgn = NodeUtil.collectNodes(ctx.getSceneGraph(), TextGridNode.class);
    	int amount = tn.size() + tgn.size();
    	return "TextNodes: " + amount;
    }
    
    public static String getItemNodes (ICanvasContext ctx) {
    	
    	Set<ItemNode> item = NodeUtil.collectNodes(ctx.getSceneGraph(), ItemNode.class);
    	int amount = item.size();
    	return "ItemNodes: " + amount;
    }
  
    public static String editNodeText (ICanvasContext ctx, String module, String previous_value, String new_value) {
    	    	
    	Set<TextNode> textGridNodes = NodeUtil.collectNodes(ctx.getSceneGraph(), TextNode.class);
    	for (TextNode modulenode : textGridNodes) {
    		if (module.equals(modulenode.getText())) {
    			//System.out.println("Module what we were looking for: " + module);
    			//System.out.println("Modulenode: " + modulenode.getText());
    			
    			ParentNode<?> parentnode = modulenode.getParent();
    			//System.out.println("Parentnode: " + parentnode);
    			
    			Collection<TextNode> textnodes = (Collection<TextNode>) parentnode.getNodes();
    			for (TextNode valuenode : textnodes) {
	    			if (previous_value.equals(valuenode.getText())) {
	        			//System.out.println("Value what we were looking for: " + previous_value);
	        			//System.out.println("Valuenode: " + valuenode.getText());
	        			
	        			//valuenode.setEditMode(true);
	        			valuenode.activateEdit(0, null, ctx);
	        			valuenode.setText(new_value);
	        			valuenode.fireTextEditingEnded();
	        			
	        			//System.out.println("valuenode modified: " + valuenode);
	        			return "Modified module " + module + " with value " + new_value;
	    			}
    			}
    			return "Not found module : " + module;
    		}
    	}
        return "No nodes in scenegraph!";
    }
    
    /**
     * Returns background color of a canvasContext or null.
     * @param ctx
     * @return color in RGBA List<Integer> format, or null.
     */
    public static List<Integer> getBackgroundColor(ICanvasContext ctx) {
    	Color color = ctx.getDefaultHintContext().getHint(Hints.KEY_BACKGROUND_COLOR);
    	if (color == null)
    		return null;
    	ArrayList<Integer> rgba = new ArrayList<>(4);
    	rgba.add(color.getRed());
    	rgba.add(color.getGreen());
    	rgba.add(color.getBlue());
    	rgba.add(color.getAlpha());
    	return rgba;
    }

    public static String sceneGraphTest (ICanvasContext ctx, String module, String value) {
    	
    	boolean module_founded = false;
    	boolean value_founded = false;
    	
    	Set<G2DSceneGraph> g2 = NodeUtil.collectNodes(ctx.getSceneGraph(), G2DSceneGraph.class);
    	System.out.println("Total amount of nodes: " + g2.size() + 1);
    	
    	Set<TextGridNode> grid = NodeUtil.collectNodes(ctx.getSceneGraph(), TextGridNode.class);
    	Integer textGridNodeAmount = grid.size();
    	System.out.println("Amount of TextGridNodes " + textGridNodeAmount);
    	
    	Set<TextNode> texts = NodeUtil.collectNodes(ctx.getSceneGraph(), TextNode.class);
    	Integer textNodeAmount = grid.size();
    	System.out.println("Amount of TextNodes " + textNodeAmount);

        for (TextNode node : texts) {
            if (module.equals(node.getText())) {
            	module_founded = true;
            	System.out.println("Correct module " + module + " founded.");
            }
            if (value.equals(node.getText())) {
            	value_founded = true;
            	System.out.println("Correct value " + value + " founded.");
            }
        }
        
        if (value_founded == true && module_founded == true) {
        	return "Found both correct module " + module + " and value " + value;
        }
        if (value_founded == false && module_founded == true) {
        	return "Found only correct module " + module + " but not value " + value;
        }
        if (value_founded == true && module_founded == false) {
        	return "Found only correct value " + value + " but not module " + module;
        }
        else {
        	return "Didn't found either module " + module + " or value " + value;
        }
    }
    
    public static boolean copyPaste (final ICanvasContext source_ctx, final ICanvasContext target_ctx, List<Resource> modules) throws DatabaseException {
    	
    	IDiagram idiagram = source_ctx.getDefaultHintContext().getHint(DiagramHints.KEY_DIAGRAM);

		DataElementMap dem = idiagram.getDiagramClass().getAtMostOneItemOfClass(DataElementMap.class);
		if (dem != null) {
			final Collection<IElement> newSelection = new ArrayList<IElement>();
			for (Resource module : modules) {
				IElement element = dem.getElement(idiagram, module);
				if (element != null) {
					newSelection.add(element);
				} else {
					throw new DatabaseException("Could not find IElement for " + element);
				}
			}
			
			ThreadUtils.syncExec(source_ctx.getThreadAccess(), new Runnable() {
	            @Override
	            public void run() {
	                if (source_ctx.isDisposed())
	                    return;
	                Selection selection = source_ctx.getAtMostOneItemOfClass(Selection.class);
	                if (selection != null) {
	                    // This prevents workbench selection from being left over.
	                    // Also prevents scene graph crap from being left on the screen.
	                    selection.setSelection(0, newSelection);
	                }
	        		CanvasUtils.sendCommand(source_ctx, Commands.COPY);
	        		CanvasUtils.sendCommand(target_ctx, Commands.PASTE);
	            }
	        });
			
		//}
		
		while(source_ctx.getEventQueue().size() > 0) {
			try {
				Thread.sleep(10);
			} catch (InterruptedException e) {
				throw new DatabaseException(e);
			}
		}

		ThreadUtils.syncExec(source_ctx.getThreadAccess(), new Runnable() {
            @Override
            public void run() {
            }
        });		
	        		
		}
		return true;
    }

	static class Generator extends SVGGraphics2D {

		int elemLevel = 0;
		String newElementId = null;
		ArrayList<Element> elements = new ArrayList<Element>();

		public static final String svgNS = "http://www.w3.org/2000/svg";

		public Generator(SVGGeneratorContext ctx, boolean textAsShapes) {
			super(ctx, textAsShapes);
		}

		public Generator(Document document) {
			super(document);
			// prevent batik comment in each g-element
			getGeneratorContext().setComment(null);
		}

		@Override
		public Element getRoot() {
			Element root = super.getRoot();
			for(Element e : elements) {
				root.appendChild(e);
			}
			return root;
		}

		@Override
		public void setRenderingHint(Key arg0, Object arg1) {
			if(G2DRenderingHints.KEY_BEGIN_ELEMENT == arg0) {
				elemLevel++;
			}
			if(G2DRenderingHints.KEY_ELEMENT_ID == arg0) {
				if(arg1 != null)
					newElementId = arg1.toString();
				else
					newElementId = UUID.randomUUID().toString();
			}
			if(G2DRenderingHints.KEY_END_ELEMENT == arg0) {
				elemLevel--;
				if(elemLevel == 0) {
					Element group = getDOMFactory().createElement(SVG_G_TAG);
					//Element group = getDOMFactory().createElementNS(SVG_NAMESPACE_URI, SVG_G_TAG);
					group.setAttributeNS(null, "id", newElementId);
					group.setAttributeNS(null, "class", arg1.toString());
					getRoot(group);
					elements.add(group);
				}
			}
			super.setRenderingHint(arg0, arg1);
		}

	}

	public static Element renderSVGNode(SVGGraphics2D svgGenerator, IG2DNode node) {

		try {

			svgGenerator.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
			svgGenerator.setRenderingHint(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);
			svgGenerator.setRenderingHint(RenderingHints.KEY_TEXT_ANTIALIASING, RenderingHints.VALUE_TEXT_ANTIALIAS_ON);

			node.render(svgGenerator);

		} catch (Throwable t) {
			LOGGER.error("Problems rendering scene graph to SVG", t);
		}

		return svgGenerator.getRoot();
	}

	public static String printSVGDocument(Element doce) {

		StringBuilder result = new StringBuilder();

		NodeList nl =  doce.getChildNodes();

		for(int i=0;i<nl.getLength();i++) {

			ByteArrayOutputStream os = new ByteArrayOutputStream();

			try {

				TransformerFactory tf = TransformerFactory.newInstance();
				Transformer transformer = tf.newTransformer();
				transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");
				transformer.setOutputProperty(OutputKeys.STANDALONE, "no");
				transformer.setOutputProperty(OutputKeys.METHOD, "xml");
				transformer.setOutputProperty(OutputKeys.INDENT, "yes");
				transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8");
				transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");

				transformer.transform(new DOMSource(nl.item(i)), 
						new StreamResult(new OutputStreamWriter(os, "UTF-8")));

				os.flush();
				os.close();

			} catch (Throwable t) {
				LOGGER.error("Problems formatting SVGDocument to text.", t);
			}

			result.append(new String(os.toByteArray()));

		}

		return result.toString();

	}

	public static String renderSVG3(ICanvasContext ctx) {
		return renderSVG3(ctx, -1, -1);
	}

	public static String renderSVG3(ICanvasContext ctx, double width, double height) {
        return renderSVG0(width, height, ctx, p0 -> p0.stream().collect(Collectors.toMap(p1 -> p1, p2 -> p2)));
	}

    /**
     * @param graph
     * @param component
     * @throws DatabaseException
     */
    private static Object[] createURIBasedL0Identifier(ReadGraph graph, Resource component) throws DatabaseException {
        String uri = graph.getPossibleURI(component);
        int hashCode = uri.hashCode();
        Random random = new Random(hashCode);
        long l1 = random.nextLong();
        long l2 = random.nextLong();
        return new Object[] { l1, l2 };
    }

    /**
     * Default no-op mapper
     */
    private static final Function1<Set<?>, Map<?, ?>> mapper = p0 -> p0.stream().collect(Collectors.toMap(p1 -> p1, p2 -> p2));

    public static String renderSVG(ICanvasContext ctx, double width, double height) {
        return renderSVG0(width, height, ctx, mapper);
    }

    public static String renderSVG(ICanvasContext ctx) {
    	return renderSVG(ctx, -1, -1);
    }

    public static String renderSVGMapIdentifiers(ICanvasContext ctx) {
		return renderSVGMapIdentifiers(ctx, -1, -1);
    }
    
    /**
     * Renders ICanvasContext into SVG by mapping the SVG id's into URI based
     * GUID's
     * 
     * @param ctx
     * @return
     */
    public static String renderSVGMapIdentifiers(ICanvasContext ctx, double width, double height) {
        return renderSVG0(width, height, ctx, new Function1<Set<?>, Map<?, ?>>() {

            @Override
            public Map<?, ?> apply(Set<?> p0) {
                try {
                    return Simantics.getSession().syncRequest(new UnaryRead<Set<?>, Map<?, ?>>(p0) {

                        @Override
                        public Map<?, ?> perform(ReadGraph graph) throws DatabaseException {
                            ModelingResources MOD = ModelingResources.getInstance(graph);
                            DiagramResource DIA = DiagramResource.getInstance(graph);
                            Layer0 L0 = Layer0.getInstance(graph);
                            return parameter.stream().collect(Collectors.toMap(p -> p, p -> {
                                try {
                                    if (p instanceof Resource) {
                                        Resource element = (Resource) p;
                                        if (graph.isInstanceOf(element, DIA.Element)) {
                                            Resource component = graph.getPossibleObject(element, MOD.ElementToComponent);
                                            if (component != null) {
                                                GUID identifier = graph.getPossibleRelatedValue(component, L0.identifier, GUID.BINDING);
                                                if (identifier != null) {
                                                    return Arrays.toString(createURIBasedL0Identifier(graph, component));
                                                } else {
                                                    LOGGER.error("Component {} does not have GUID identifier!", component);
                                                }
                                            } else if (graph.isInstanceOf(element, DIA.Connection) || graph.isInstanceOf(element, DIA.Terminal)) {
                                                // Ok, lets create a hashcode for connections and terminals as they do not have identifiers 
                                                return graph.getURI(element).hashCode();
                                            } else {
                                                // Ok, lets create a hashcode or either return empty string in cases where no ID is required
                                                if (graph.hasStatement(element, L0.HasName))
                                                    return graph.getURI(element).hashCode();
                                                return "";
                                            }
                                        }
                                    } else {
                                        LOGGER.error("Parameter p {} is not resource but it is {}", p, p.getClass());
                                    }
                                    return p;
                                } catch (DatabaseException e) {
                                    throw new RuntimeDatabaseException(e);
                                }
                            }));
                        }
                    });
                } catch (DatabaseException e) {
                    LOGGER.error("Could not apply mappings", e);
                    throw new RuntimeDatabaseException(e);
                }
            }
        });
	}
	
    static class RenderSVGContext {
    	
    	Map<String,StringBuilder> documents = new HashMap<>();
    	
    	public void append(String[] keys, String svgText) {
    		for(String key : keys) append(key, svgText);
    	}

    	public void append(String key, String svgText) {
    		StringBuilder builder = documents.get(key);
    		if(builder == null) {
    			builder = new StringBuilder();
    			documents.put(key, builder);
    		}
    		builder.append(svgText);
    	}
    	
    	public void append(RenderSVGContext other) {
    		for(String key : other.documents.keySet()) {
    			append(key, other.get(key));
    		}
    	}
    	
    	public String get(String key) {
    		StringBuilder builder = documents.get(key);
    		if(builder == null) return "";
    		else return builder.toString();
    	}
    	
    }
    
	private static String renderSVG0(double width, double height, ICanvasContext ctx, Function1<Set<?>, Map<?, ?>> mappingFunction) {

		// Get a DOMImplementation.
		DOMImplementation domImpl = GenericDOMImplementation.getDOMImplementation();

		// Create an instance of org.w3c.dom.Document.
		String svgNS = "http://www.w3.org/2000/svg";
		Document document = domImpl.createDocument(svgNS, "svg", null);

		// Create an instance of the SVG Generator.
		SVGGraphics2D svgGenerator = new Generator(document);

		RenderSVGContext result = new RenderSVGContext();

		double[] matrix = new double[6];
		try {

            Selection selection = ctx.getAtMostOneItemOfClass(Selection.class);
            if (selection != null) {
                // This prevents workbench selection from being left over.
                // Also prevents scene graph crap from being left on the screen.
            	IDiagram d = ctx.getDefaultHintContext().getHint(DiagramHints.KEY_DIAGRAM);
                selection.setSelection(0, d.getElements());
            }

			G2DSceneGraph sg = ctx.getSceneGraph();
			sg.performCleanup();
			G2DParentNode root = (G2DParentNode) sg.getRootNode();

			// rtree is the actual content of the diagram
			RTreeNode rtree = NodeUtil.getNearestChildByClass(root, RTreeNode.class);
			Rectangle2D rtreeBounds = NodeUtil.getLocalBounds(rtree);

			// get the bounds of the content
			Rectangle2D content = rtreeBounds;
			
			// To account for dynamic padding of selection rectangles (5 units + stroke width)
			int offset = 6;
			
			double scale = width < 0 || height < 0 ? 1.0 : Math.min((width - 2*offset) / content.getWidth(), (height - 2*offset) / content.getHeight());
		
			AffineTransform tr = new AffineTransform();
			tr.translate(offset, offset);
			tr.scale(scale, scale);
			tr.translate(-content.getX(), -content.getY());
			tr.getMatrix(matrix);
			//svgGenerator.translate(offset, offset);
			//svgGenerator.scale(scale, scale);
			// translate svgGenerator to the x and y coordinates of current content
			//svgGenerator.translate(-content.getX(), -content.getY());

			svgGenerator.setSVGCanvasSize(new Dimension((int)Math.ceil(scale * content.getWidth()) + 2*offset, (int)Math.ceil(scale * content.getHeight()) + 2*offset));
			//svgGenerator.setClip(content);
			
			result.append(MAIN_SECTION, "<g class=\"symbols\">");
			result.append(SELECTION_SECTION, "<g class=\"selections\">");
			result.append(SELECTION_MASK_SECTION, "<g class=\"selectionMasks\">");

			KeyVisitor keyVisitor = new KeyVisitor();
			sg.accept(keyVisitor);
			
			Set<Object> keys = keyVisitor.getKeys();
			
			Map<?, ?> mappings = mappingFunction.apply(keys);

			IG2DNodeVisitor visitor = new PrintingVisitor(svgGenerator, result, mappings);
			
			sg.accept(visitor);

		} catch (Throwable t) {
			LOGGER.error("Problems rendering canvas context to SVG", t);
		}


		result.append(ALL_SECTIONS, "</g>");

		StringBuilder res = new StringBuilder();
		res.append("<svg width=\"100%\" height=\"100%\" stroke=\"black\">");
		res.append("<g transform=\"matrix(").append(matrix[0]).append(",").append(matrix[1]).append(",").append(matrix[2]).append(",").append(matrix[3]).append(",").append(matrix[4]).append(",").append(matrix[5]).append(")\">");
		res.append(result.get(MAIN_SECTION));
		res.append(result.get(SELECTION_SECTION));
		res.append(result.get(SELECTION_MASK_SECTION));
		res.append("</g>");
		res.append("</svg>");

//		System.err.println(" == FINAL RESULT == ");
//		System.err.println(res.toString());
		
		return res.toString();
		
	}
	
	
	
	private static class KeyVisitor implements IG2DNodeVisitor {

        private Set<Object> keys = new HashSet<>();

        @Override
        public void enter(IG2DNode node) {
            if (node instanceof SingleElementNode) {
                Object key = ((SingleElementNode) node).getKey();
                if (key != null) {
                    keys.add(key);
                }
            }
        }

        @Override
        public void leave(IG2DNode node) {
            // Nothing to do
        }

        public Set<Object> getKeys() {
            return keys;
        }
	}

	private static class PrintingVisitor implements IG2DNodeVisitor {

        int indent = 0;

        HashMap<SingleElementNode,RenderSVGContext> senBuilders = new HashMap<>();

        private RenderSVGContext result;
        private SVGGraphics2D svgGenerator;

        private Map<?, ?> mappings;

        public PrintingVisitor(SVGGraphics2D svgGenerator, RenderSVGContext result, Map<?, ?> mappings) {
            this.result = result;
            this.mappings = mappings;
            this.svgGenerator = svgGenerator;
        }

        private String getKey(SingleElementNode node) {
            String key;
        	if(node.getKey() != null) {
                if (mappings.containsKey(node.getKey()))
                    key = mappings.get(node.getKey()).toString();
                else
                    key = node.getKey().toString();
        	} else {
        		key = Long.toString(node.getId());
        	}
            return key;
        }

        @Override
        public void enter(IG2DNode node) {
            
        	RenderSVGContext parentBuilder = getParentBuilder(node);
            
            indent++;
            if(node instanceof ConnectionNode) {
                
                for(RouteGraphNode n : NodeUtil.collectNodes(node, RouteGraphNode.class)) {
                    n.setIgnoreSelection(true);
                }

                String key = getKey((ConnectionNode) node);
                parentBuilder.append(MAIN_SECTION, "\n<g class=\"connection\" id=\"" + key + "\">");
                parentBuilder.append(SELECTION_SECTION, "\n<g style=\"visibility:hidden\" class=\"selection\" id=\"" + key + "\">");
                parentBuilder.append(SELECTION_MASK_SECTION, "\n<g class=\"selectionMask\" opacity=\"0.001\" id=\"" + key + "\">");
                
                Element doc = renderSVGNode(svgGenerator, (IG2DNode)node);
                String svg = printSVGDocument(doc);
                parentBuilder.append(MAIN_SECTION, svg);

                for(RouteGraphNode n : NodeUtil.collectNodes(node, RouteGraphNode.class)) {
                    n.setIgnoreSelection(false);
                }

                doc = renderSVGNode(svgGenerator, (IG2DNode)node);
                svg = printSVGDocument(doc);
                parentBuilder.append(SELECTION_SECTION, svg);

                BasicStroke bs = new BasicStroke(10f);
                
                for(RouteGraphNode n : NodeUtil.collectNodes(node, RouteGraphNode.class)) {
                    n.setDynamicStroke(bs);
                }

                doc = renderSVGNode(svgGenerator, (IG2DNode)node);
                svg = printSVGDocument(doc);
                parentBuilder.append(SELECTION_MASK_SECTION, svg);

                parentBuilder.append(SELECTION_MASK_SECTION, "\n</g>");
                parentBuilder.append(SELECTION_SECTION, "\n</g>");
                parentBuilder.append(MAIN_SECTION, "\n</g>");
                
            } else if (node instanceof SelectionNode) {
                
                SelectionNode n = (SelectionNode)node;
                SingleElementNode parentSEN = (SingleElementNode)NodeUtil.getNearestParentOfType(node, SingleElementNode.class);
                if(parentSEN != null) {
                    
                	RenderSVGContext parentBuilder2 = getParentBuilder(parentSEN);
                    
                    String key = getKey(parentSEN);
                    n.setIgnore(false);
                    Element doc = renderSVGNode(svgGenerator, (IG2DNode)node);
                    n.setIgnore(true);
                    String svg = printSVGDocument(doc);
                    parentBuilder2.append(SELECTION_SECTION, "\n<g style=\"visibility:hidden\" class=\"selection\" id=\"" + key + "\">");
                    parentBuilder2.append(SELECTION_SECTION, svg);
                    parentBuilder2.append(SELECTION_SECTION, "\n</g>");
                    parentBuilder2.append(SELECTION_MASK_SECTION, "\n<g class=\"selectionMask\" id=\"" + key /*+ "\" transform=\"" + matrixString + "\"*/+ "\">");
                    Rectangle2D rect = n.getRect();
                    // NaN
                    if(rect.getHeight() == rect.getHeight() && rect.getWidth() == rect.getWidth()) {
	                    parentBuilder2.append(SELECTION_MASK_SECTION,"<rect style=\"fill:#fff\" opacity=\"0.001\"");
	                    parentBuilder2.append(SELECTION_MASK_SECTION," x=\"" + rect.getX() + "\" y=\"" + rect.getY() + "\"");
	                    parentBuilder2.append(SELECTION_MASK_SECTION," width=\"" + rect.getWidth() + "\" height=\"" + rect.getHeight() + "\"");
	                    parentBuilder2.append(SELECTION_MASK_SECTION,"></rect>");
                    }
                    parentBuilder2.append(SELECTION_MASK_SECTION,"\n</g>");
                   
                }
            } else if (node instanceof SVGNode) {
                SVGNode svg = (SVGNode)node;
                AffineTransform at = svg.getTransform();
                if (!at.isIdentity()) {
                	 if(at.getScaleX() == 1.0 && at.getScaleY() == 1.0 && at.getShearX() == 0.0 && at.getShearY() == 0.0) {
                         String m = "translate(" + at.getTranslateX() + " " + at.getTranslateY() + ")";
                         parentBuilder.append(MAIN_SECTION, "\n<g transform=\"" + m + "\">");
                     } else {
                         double[] ds = new double[6];
                         at.getMatrix(ds);
                         String m = "matrix(" + ds[0] + " " + ds[1] + " " + ds[2] + " " + ds[3] + " " + ds[4] + " " + ds[5] + ")";
                         parentBuilder.append(MAIN_SECTION, "\n<g transform=\"" + m + "\">");
                     }
                }
                parentBuilder.append(MAIN_SECTION, svg.getSVGText());
                if (!at.isIdentity()) {
                	parentBuilder.append(MAIN_SECTION, "\n</g>");
                }
            } else if (node instanceof G2DParentNode) {
                AffineTransform at = node.getTransform();
                if(node instanceof SingleElementNode) {
                    SingleElementNode sen = (SingleElementNode)node;
                    String key = getKey(sen);
                    String typeClass = sen.getTypeClass();
                    String clazz = "definedElement";
                    if(typeClass != null && !typeClass.isEmpty())
                    	clazz = clazz + " " + typeClass;

                    parentBuilder.append(MAIN_SECTION, "\n<g class=\""+clazz+"\" id=\"" + key + "\">");
                    senBuilders.put(sen, new RenderSVGContext());
                }
                if(!at.isIdentity()) {
                    if(at.getScaleX() == 1.0 && at.getScaleY() == 1.0 && at.getShearX() == 0.0 && at.getShearY() == 0.0) {
                        String m = "translate(" + at.getTranslateX() + " " + at.getTranslateY() + ")";
                        parentBuilder.append(ALL_SECTIONS, "\n<g transform=\"" + m + "\">");
                    } else {
                        double[] ds = new double[6];
                        at.getMatrix(ds);
                        String m = "matrix(" + ds[0] + " " + ds[1] + " " + ds[2] + " " + ds[3] + " " + ds[4] + " " + ds[5] + ")";
                        parentBuilder.append(ALL_SECTIONS, "\n<g transform=\"" + m + "\">");
                    }
                }
            }

            //enters.put(node, b.length());

        }
        
        private RenderSVGContext getParentBuilder(IG2DNode node) {
            
            INode parentSEN = NodeUtil.getNearestParentOfType(node, SingleElementNode.class);
            if(parentSEN instanceof G2DSceneGraph) return result;

            RenderSVGContext parentBuilder = senBuilders.get(parentSEN);
            if(parentBuilder == null) return result;
            
            return parentBuilder;
            
        }

        @Override
        public void leave(IG2DNode node) {

            if(node instanceof ConnectionNode || node instanceof SVGNode) {
                // We are done
            } else if (node instanceof G2DParentNode) {
                
            	RenderSVGContext parentBuilder = getParentBuilder(node);
                
                if(node instanceof SingleElementNode) {
                	SingleElementNode sen = (SingleElementNode)node;
                	RenderSVGContext b = senBuilders.get(sen);
                	String content = b.get(MAIN_SECTION);
                	if(content.isEmpty()) {
                		if(sen.getKey() != null) {

                			for(SelectionNode n : NodeUtil.collectNodes(node, SelectionNode.class)) {
                				n.setIgnore(true);
                			}

                			Element doc = renderSVGNode(svgGenerator, (IG2DNode)node);
                			String svg = printSVGDocument(doc);
                			parentBuilder.append(MAIN_SECTION, svg);
                		}
                	} else {
                		parentBuilder.append(b);
                	}
                }
                
                AffineTransform at = node.getTransform();
                if(!at.isIdentity()) {
                    parentBuilder.append(ALL_SECTIONS, "</g>");
                }
                if(node instanceof SingleElementNode) {
                    SingleElementNode sen = (SingleElementNode)node;
                    //if(sen.getKey() != null) {
                        parentBuilder.append(MAIN_SECTION, "</g>");
                    //}
                }
            }
            indent --;
        }
	}
}