/*******************************************************************************
 * Copyright (c) 2012 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.maps.eclipse;

import org.simantics.g2d.canvas.Hints;
import org.simantics.g2d.canvas.ICanvasContext;
import org.simantics.g2d.canvas.impl.AbstractCanvasParticipant;
import org.simantics.g2d.canvas.impl.SGNodeReflection.SGCleanup;
import org.simantics.g2d.canvas.impl.SGNodeReflection.SGInit;
import org.simantics.maps.sg.MapNode;
import org.simantics.maps.sg.MapScaleNode;
import org.simantics.scenegraph.g2d.G2DParentNode;
import org.simantics.scenegraph.g2d.events.EventHandlerReflection.EventHandler;
import org.simantics.scenegraph.g2d.events.command.CommandEvent;
import org.simantics.scenegraph.g2d.events.command.Commands;
import org.simantics.utils.datastructures.hints.HintListenerAdapter;
import org.simantics.utils.datastructures.hints.IHintListener;
import org.simantics.utils.datastructures.hints.IHintObservable;
import org.simantics.utils.datastructures.hints.IHintContext.Key;
import org.simantics.utils.datastructures.hints.IHintContext.KeyOf;

/**
 * MapPainter is an ICanvasContext participant that uses the scene graph
 * {@link MapNode} to draw tiled maps in the background of the canvas.
 * 
 * @author J-P Laine
 * 
 * @see MapNode
 */
public class MapPainter extends AbstractCanvasParticipant {

    /**
     * Grid enabled status. Default value is True
     */
    public static final Key KEY_MAP_ENABLED  = new KeyOf(Boolean.class);

    public static final double ZOOM_IN_LIMIT = 10000000.0;

    public static final double ZOOM_OUT_LIMIT = 10.0;

    IHintListener mapListener = new HintListenerAdapter() {
        public void hintChanged(IHintObservable sender, Key key, Object oldValue, Object newValue) {
            ICanvasContext cc = getContext();
            if (cc != null) {
                updateNode();
                cc.getContentContext().setDirty();
            }
        }
    };

    protected MapNode node = null;
    protected MapScaleNode scaleNode = null;

    private int scale;

    public MapPainter(int scale) {
        this.scale = scale;
    }

    @Override
    public void addedToContext(ICanvasContext ctx) {
        super.addedToContext(ctx);
        getHintStack().addKeyHintListener(getThread(), KEY_MAP_ENABLED, mapListener);
    }

    @Override
    public void removedFromContext(ICanvasContext ctx) {
        getHintStack().removeKeyHintListener(getThread(), KEY_MAP_ENABLED, mapListener);
        super.removedFromContext(ctx);
    }

    @EventHandler(priority = 0)
    public boolean handleKeyEvent(CommandEvent e) {
        if (e.command.equals( Commands.MAP_ENABLE )) {
            setEnabled(true);
            updateNode();
            setDirty();
            return true;
        } else if (e.command.equals( Commands.MAP_DISABLE )) {
            setEnabled(false);
            updateNode();
            setDirty();
            return true;
        } else if (e.command.equals( Commands.MAP_TOGGLE )) {
            setEnabled(!isMapEnabled());
            updateNode();
            setDirty();
            return true;
        }
        return false;
    }

    @SGInit
    public void initSG(G2DParentNode parent) {
        node = parent.addNode("map", MapNode.class);
        node.setScale(scale);
        node.setEnabled(true);
        node.setZIndex(Integer.MIN_VALUE + 999); // Just under the grid
        
        scaleNode = parent.addNode("mapScale", MapScaleNode.class);
        scaleNode.setScale(scale);
        scaleNode.setEnabled(true);
        scaleNode.setZIndex(Integer.MAX_VALUE - 999); // Just under the grid
    }

    @SGCleanup
    public void cleanupSG() {
        node.remove();
    }

    protected void updateNode() {
        node.setEnabled(isPaintingEnabled());
    }

    boolean isPaintingEnabled() {
        boolean enabled = isMapEnabled();
        Boolean globalDisable = getHint(Hints.KEY_DISABLE_PAINTING);
        return enabled && !Boolean.TRUE.equals(globalDisable);
    }

    public boolean isMapEnabled() {
        Boolean enabled = getHint(KEY_MAP_ENABLED);
        return !Boolean.FALSE.equals(enabled);
    }

    public void setEnabled(boolean enabled) {
        setHint(KEY_MAP_ENABLED, enabled);
    }

}