/*******************************************************************************
 * 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.g2d.participant;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Paint;
import java.awt.Shape;
import java.awt.Stroke;
import java.awt.geom.AffineTransform;
import java.awt.geom.Path2D;
import java.util.Map;

import org.simantics.g2d.canvas.SGDesignation;
import org.simantics.g2d.canvas.impl.AbstractCanvasParticipant;
import org.simantics.g2d.canvas.impl.DependencyReflection.Dependency;
import org.simantics.g2d.canvas.impl.SGNodeReflection.SGCleanup;
import org.simantics.g2d.canvas.impl.SGNodeReflection.SGInit;
import org.simantics.g2d.participant.MouseUtil.MouseInfo;
import org.simantics.scenegraph.g2d.G2DParentNode;
import org.simantics.scenegraph.g2d.events.MouseEvent;
import org.simantics.scenegraph.g2d.events.EventHandlerReflection.EventHandler;
import org.simantics.scenegraph.g2d.events.MouseEvent.MouseButtonPressedEvent;
import org.simantics.scenegraph.g2d.events.MouseEvent.MouseButtonReleasedEvent;
import org.simantics.scenegraph.g2d.events.MouseEvent.MouseMovedEvent;
import org.simantics.scenegraph.g2d.nodes.InstancingShapeNode;
import org.simantics.utils.datastructures.hints.IHintContext.Key;
import org.simantics.utils.datastructures.hints.IHintContext.KeyOf;

/**
 * Paints mouse cursors in a multi-mouse setup.
 * 
 * @author Toni Kalajainen
 * @author Tuukka Lehtonen
 */
public class PointerPainter extends AbstractCanvasParticipant {

    /**
     * Key for the hint that determines whether cursors are painter or not.
     */
    public static final Key     KEY_PAINT_POINTER     = new KeyOf(Boolean.class);

    public static final int     CURSOR_PAINT_Z_ORDER = 5000;

    private final static Stroke CURSOR_STROKE         = new BasicStroke(1.0f);

    @Dependency MouseUtil       monitor;

    InstancingShapeNode         node;

    Shape                       pointer;

    public PointerPainter() {
        Path2D p = new Path2D.Double();
        p.moveTo(-10, -10);
        p.lineTo(10, 10);
        p.moveTo(10, -10);
        p.lineTo(-10, 10);

        this.pointer = p;
    }

    @SGInit(designation = SGDesignation.CONTROL)
    public void init(G2DParentNode parent) {
        node = parent.addNode("pointers", InstancingShapeNode.class);
        node.setZIndex(CURSOR_PAINT_Z_ORDER);
        node.setShape(pointer);
        node.setStroke(CURSOR_STROKE);
        node.setFill(false);
        node.setScaleStroke(false);
        node.setScaleShape(false);
    }

    @SGCleanup
    public void cleanup() {
        node.remove();
        node = null;
    }

    public boolean isCursorEnabled() {
        Boolean pp = getHint(KEY_PAINT_POINTER);
        return Boolean.TRUE.equals(pp);
    }

    @EventHandler(priority = Integer.MAX_VALUE)
    public boolean handleMouseEvent(MouseEvent e) {
        if (!isCursorEnabled())
            return false;

        assertDependencies();

        if (e instanceof MouseMovedEvent || e instanceof MouseButtonPressedEvent
                || e instanceof MouseButtonReleasedEvent) {
            updateNode();
            setDirty();
        }
        return false;
    }

    private void updateNode() {
        Map<Integer, MouseInfo> miceInfo = monitor.getMiceInfo();

        AffineTransform[] transforms = new AffineTransform[miceInfo.size()];
        Paint[] paints = new Paint[miceInfo.size()];

        int i = 0;
        for (MouseInfo mi : miceInfo.values()) {
            int color = 0;
            if ((mi.buttons & 1) > 0) color |= 0xff;
            if ((mi.buttons & 2) > 0) color |= 0xff00;
            if ((mi.buttons & 4) > 0) color |= 0xff0000;

            transforms[i] = AffineTransform.getTranslateInstance(mi.controlPosition.getX(), mi.controlPosition.getY());
            paints[i] = new Color(color);

            ++i;
        }

        node.setInstances(transforms, paints);
    }

}