/*******************************************************************************
 * Copyright (c) 2007, 2010 Association for Decentralized Information Management
 * in Industry THTH ry.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
package org.simantics.diagram.adapter;

import java.awt.Shape;
import java.awt.geom.Rectangle2D;
import java.util.Collection;
import java.util.EnumSet;
import java.util.List;

import org.simantics.g2d.element.ElementClass;
import org.simantics.g2d.element.ElementHints;
import org.simantics.g2d.element.ElementUtils;
import org.simantics.g2d.element.IElement;
import org.simantics.g2d.element.SceneGraphNodeKey;
import org.simantics.g2d.element.handler.SceneGraph;
import org.simantics.g2d.image.Image;
import org.simantics.scenegraph.INode;
import org.simantics.scenegraph.Node;
import org.simantics.scenegraph.g2d.G2DParentNode;
import org.simantics.scenegraph.g2d.nodes.SingleElementNode;
import org.simantics.utils.datastructures.hints.IHintContext.Key;

/**
 * Element Composition -> Image
 *
 * @author Toni Kalajainen <toni.kalajainen@vtt.fi>
 */
public class CompositeImage implements Image {

    Collection<IElement> elements;
    private Shape shape;
    private Rectangle2D bounds;
    //IHintContext parentHints;
    static EnumSet<Feature> feats = VOLATILE_VECTOR;

    public static final Key  KEY_SG_NODE             = new SceneGraphNodeKey(Node.class, "COMPOSITE_IMAGE_SG_NODE");

    public CompositeImage(Collection<IElement> elements)
    {
        //this.nodeIdentifier = nodeIdentifier;
        this.elements = elements;
//        ITask task = ThreadLogger.getInstance().begin("getElementShapesOnDiagram");
        // getElementShapesOnDiagram is ridiculously slow with some input data..
        // With Balas it took almost 2sec to calculate one Area.add() for the last terminal element.
        //shape = ElementUtils.getElementShapesOnDiagram(elements);
//        shape = ElementUtils.getElementBoundsOnDiagram(elements);
  //      task.finish();
//        bounds = shape.getBounds2D();
    }

    @Override
    public Rectangle2D getBounds() {
        if(bounds == null) {
            Shape shape = getShape();
            // Shape may be null.
            if (shape == null)
                return new Rectangle2D.Double();
            bounds = shape.getBounds2D();
        }
        return bounds;
    }

    @Override
    public EnumSet<Feature> getFeatures() {
        return feats;
    }

    private final Shape getShape() {
        if(shape == null) {
            shape = ElementUtils.getElementBoundsOnDiagram(elements);
        }
        return shape;
    }

    @Override
    public Shape getOutline() {
        return getShape();
    }

    public Collection<IElement> getElements() {
        return elements;
    }

    @Override
    public void addImageListener(ImageListener listener) {
    }

    @Override
    public void removeImageListener(ImageListener listener) {
    }

//    public void setParentHints(IHintContext hints) {
//        this.parentHints = hints;
//    }

    // Rendering is single-threaded, this is used while rendering.
    //Rectangle2D tempBounds = new Rectangle2D.Double(0, 0, 0, 0);

    @Override
    public Node init(G2DParentNode parent) {
        if (elements.size() < 2) {
            // Optimization for 0..1 element composites
            for (IElement e : elements) {
                ElementClass ec = e.getElementClass();
                G2DParentNode node = getOrCreateParentNode(parent);
                List<SceneGraph> nodeHandlers = ec.getItemsByClass(SceneGraph.class);
                for (SceneGraph n : nodeHandlers) {
//                    n.init(e, parent);
                    n.init(e, node);
                }
                return node; // Valid node must be returned because transform is set afterwards
            }
        }

        // For N element composites

        G2DParentNode node = getOrCreateParentNode(parent);
//        Rectangle2D bounds = tempBounds;

        int zIndex = 0;
        for (IElement e : elements) {
            ElementClass ec = e.getElementClass();
//            InternalSize size = ec.getSingleItem(InternalSize.class);
//            size.getBounds(e, bounds);

//            Transform transform = e.getElementClass().getSingleItem(Transform.class);
//            AffineTransform at2 = transform.getTransform(e);
//            if (at2 == null)
//                continue;
            SingleElementNode holder = node.getOrCreateNode(ElementUtils.generateNodeId(e), SingleElementNode.class);
            //SingleElementNode holder = parent.getOrCreateNode(ElementUtils.generateNodeId(e), SingleElementNode.class);
            holder.setZIndex(++zIndex);
            holder.setKey(e.getHint(ElementHints.KEY_OBJECT));
            holder.setTypeClass(e.getHint(ElementHints.KEY_TYPE_CLASS));

            List<SceneGraph> nodeHandlers = ec.getItemsByClass(SceneGraph.class);
            for(SceneGraph n : nodeHandlers) {
                n.init(e, holder);
            }
        }

        return node; // Valid node must be returned because transform is set afterwards
    }

    private G2DParentNode getOrCreateParentNode(G2DParentNode parent) {
        G2DParentNode node = (G2DParentNode)parent.getNode("composite_image_"+this.hashCode());
        if (node == null) {
            for (INode n : parent.getNodes()) {
                // #7663: prevent the code from removing other element graphics from directly under another element
                if (!(n instanceof SingleElementNode))
                    n.remove();
            }
            // Removed this grouping node as unnecessary, just use the given parent node
            node = parent.getOrCreateNode("composite_image_"+this.hashCode(), G2DParentNode.class);
        }
        return node;
    }

}