import java.applet.Applet;
import netscape.javascript.JSObject;
import java.awt.*;
import java.awt.event.*;
import com.jinsight.jetchart.*;

public class AppJS extends Applet implements SerieListener {

	JSObject window;

	public void init() {
 
		// Gets a reference to this applet window object.
		window = JSObject.getWindow(this);

		setLayout(new BorderLayout());

		// Creates a Graph object.
		Graph graph = new Graph();
		
		// Creates a line series.
		LineSerie ls = new LineSerie();
		ls.setColor(Color.blue);
		ls.setValues(new double[] { 80, 50, 30, 100,40,200,100,20,10,40,70,80 });
		graph.addSerie(ls);
		
		// Registers this applet as a SerieListener object, to receive mouse events 
		// from the chart context.
		graph.addSerieListener(this);

		// Enables data point dragging.
		graph.setSerieDraggingEnabled(true);
		
		add(graph);

	}

	// Handles clicks on data points.
	public void serieClicked(SerieEvent evt) {
		
		// Gets the index of the data point.
		int index = evt.getElementIndex();
		
		// Gets the value of the data point.
		LineSerie ls = (LineSerie)evt.getSerie();
		double[] d = ls.getValues();
		double dd = d[index];
		
		// Evaluates a javascript expression, showing an alert box.
		String msg = "Data point value: "+dd;
		
		window.eval("javascript:alert('"+msg+"')");
				
	}
 	
	// Handles data point dragging.
	public void serieDragged(SerieEvent evt) {
		
		int index = evt.getElementIndex();
		
		LineSerie ls = (LineSerie)evt.getSerie();
		double[] d = ls.getValues();
		double dd = d[index];
		
		// Calls a Javascript function to communicate with another applet.
		window.call("dragged",new Object[]{new Integer(index),new Double(dd)});
		
		// Calls the mouseMoved handler to update the window text field when
		// a data point is dragged.
		mouseMoved(evt);
			
	}

	// Handles mouse-move events on data point.
	public void mouseMoved(SerieEvent evt) {

		int index = evt.getElementIndex();
		
		// A flag to prevent execution of the following code when cursor 
		// is not on a data point.
		boolean hasCleaned=false;
		
		if (index != -1) {
			
				LineSerie ls = (LineSerie) evt.getSerie();
				double[] d = ls.getValues();
				double dd = d[index];
						
				// The text field can be updated either by calling a Javascript
				// function called 'moved' or setting its value property directly.
				
				//window.call("moved", new Double[] { new Double(dd) });
				JSObject doc = (JSObject)window.getMember("document");
				JSObject form = (JSObject)doc.getMember("form");
				JSObject text = (JSObject)form.getMember("text");
				text.setMember("value",""+dd);
							
				hasCleaned=false;
				
		}
		else if (!hasCleaned) { // Cleans the text field.
			window.call("cleanText",null);
			hasCleaned=true;
		}
		
	}
	
	public void serieReleased(SerieEvent evt) {

	}
	

}