/* **********************************************************************
 *
 *  ROLANDS & ASSOCIATES Corporation
 *  500 Sloat Avenue
 *  Monterey, CA 93940
 *  (831) 373-2025
 *
 *  Copyright (C) 2002, 2003 ROLANDS & ASSOCIATES Corporation. All rights reserved.
 *  Openmap is a trademark of BBN Technologies, A Verizon Company
 *
 *
 * **********************************************************************
 *
 * $Source: /home/jtlsdev/src/wej/java_client/com/rolands/jtlsweb/map/layer/ScaleDisplayLayer.java,v $
 * $Revision: 1.2 $
 * $Date: 2003/02/18 16:11:33 $
 * $Author: ward $
 *
 * **********************************************************************
 */

package com.rolands.jtlsweb.map.layer;
/**
 * Layer objects are components which can be added to the MapBean to
 * make a map.
 * <p>
 * Layers implement the ProjectionListener interface to listen for
 * ProjectionEvents.  When the projection changes, they may need to
 * refetch, regenerate their graphics, and then repaint themselves
 * into the new view.
 */
public class ScaleDisplayLayer extends com.bbn.openmap.Layer {
    

    com.bbn.openmap.omGraphics.OMGraphicList graphics = new com.bbn.openmap.omGraphics.OMGraphicList();
    
    public ScaleDisplayLayer() {
        super();        
    }
    /**
     * Sets the properties for the <code>Layer</code>.  This allows
     * <code>Layer</code>s to get a richer set of parameters than the
     * <code>setArgs</code> method.
     * @param prefix the token to prefix the property names
     * @param props the <code>Properties</code> object
     */
    public void setProperties(String prefix, java.util.Properties props) {
        super.setProperties(prefix, props);
    }
    
    /**
     * Invoked when the projection has changed or this Layer has been
     * added to the MapBean.
     * @param e ProjectionEvent
     */
    com.bbn.openmap.proj.Projection projection;
        
    public void projectionChanged(com.bbn.openmap.event.ProjectionEvent e) {
        projection = e.getProjection();
        createGraphics();
        repaint();
    }
    
    public void createGraphics() {
        int w = projection.getWidth();
        int h = projection.getHeight();
        int left_x = w-10-150;
        int right_x = w-10;
        int lower_y = h-10;
        int upper_y = h-10-10;
        
        graphics.clear();
        com.bbn.openmap.omGraphics.OMLine line = new com.bbn.openmap.omGraphics.OMLine(left_x, lower_y, right_x, lower_y);
        graphics.add(line);
        line = new  com.bbn.openmap.omGraphics.OMLine(left_x, lower_y, left_x, upper_y);
        graphics.add(line);
        line = new  com.bbn.openmap.omGraphics.OMLine(right_x, lower_y, right_x, upper_y);
        graphics.add(line);
        com.bbn.openmap.LatLonPoint loc1 = projection.inverse(left_x, lower_y);
        com.bbn.openmap.LatLonPoint loc2 = projection.inverse(right_x, lower_y);
        float dist = com.bbn.openmap.proj.GreatCircle.spherical_distance(com.bbn.openmap.proj.ProjMath.degToRad(loc1.getLatitude()), com.bbn.openmap.proj.ProjMath.degToRad(loc1.getLongitude()), com.bbn.openmap.proj.ProjMath.degToRad(loc2.getLatitude()), com.bbn.openmap.proj.ProjMath.degToRad(loc2.getLongitude()));
        dist = com.rolands.util.Convert.radiansToKm(dist);
        String outtext = ""+dist+"Km";
        
        if (dist >100) {
            outtext = ""+(int)dist+"Km";
        } else if (dist > 1) {
            outtext = ""+(int)((dist*10f)/10f)+"Km";
        } else {
            outtext = ""+(int)(dist*1000f)+"m";
        }
         
        com.bbn.openmap.omGraphics.OMText text = new com.bbn.openmap.omGraphics.OMText((left_x+right_x)/2, lower_y-3, ""+outtext, com.bbn.openmap.omGraphics.OMText.JUSTIFY_CENTER);
        graphics.add(text);        
        graphics.generate(projection);
    }
    /**
     * Paints the layer.
     * @param g the Graphics context for painting
     */
    public void paint(java.awt.Graphics g) {
        graphics.render(g);
    }
    

    
}