import java.awt.event.ActionListener;
import javax.swing.*;
import java.awt.*;
import java.util.*;

import com.sun.star.awt.XFocusListener;
import com.sun.star.uno.UnoRuntime;
import com.sun.star.bridge.XUnoUrlResolver;
import com.sun.star.lang.XMultiServiceFactory;
import com.sun.star.accessibility.*;
import com.sun.star.awt.XExtendedToolkit;


/** This timer task tries to connect to a running Office application in regular
    intervals until a connection can be successfully established.
*/
class ConnectionTask
    extends TimerTask
{
    public ConnectionTask (EventListenerProxy xListener)
    {
        Init (xListener);
    }



    public ConnectionTask (EventListenerProxy xListener, int nPortNumber, String sHostName)
    {
        mnPortNumber = nPortNumber;
        msHostName = sHostName;
        Init (xListener);
    }

    private void Init (EventListenerProxy xListener)
    {
        mxListener = xListener;
        mbInitialized = false;

        maTimer = new java.util.Timer ();
        maTimer.schedule (this, 0, mnPeriod);
    }


    /** This method is run every time the task is executed.  It tries to
        connect to and register the listener at an Office application.  If it
        can establish a connection it terminates the timer task.  Otherwise it
        waits until the next activation.
    */
    public void run ()
    {
        if (registerListeners())
        {
            // Focus listener was successfully registered so we can cancel this task.
            MessageArea.println ("\nconnected successfully to office");
            cancel ();
            maTimer = null;
        }
    }




    /** Try to register the listener.
    */
    private boolean registerListeners ()
    {
        // Get toolkit.
        XExtendedToolkit xToolkit = getToolkit ();

        // Register at toolkit as focus event listener.
        if (xToolkit != null)
        {
            xToolkit.addTopWindowListener (mxListener);
            int nTopWindowCount = xToolkit.getTopWindowCount();
            try
            {
                com.sun.star.lang.EventObject aEvent = new com.sun.star.lang.EventObject();
                for (int i=0; i<nTopWindowCount; i++)
                {
                    XAccessible xAccessible = (XAccessible) UnoRuntime.queryInterface(
                        XAccessible.class,
                        xToolkit.getTopWindow(i));
                    XAccessibleContext xContext = xAccessible.getAccessibleContext();
                    if (xContext.getAccessibleName().length() > 0)
                    {
                        // Simulate an event that leads to registration the
                        // listener at the window.
                        aEvent.Source = xToolkit.getTopWindow(i);
                        mxListener.windowOpened (aEvent);
                    }
                }
            }

            catch (com.sun.star.lang.IndexOutOfBoundsException aException)
            {
                // This exception signals that the number of top windows has
                // changed since our last call to getTopWindowCount().
            }
            return true;
        }
        else
            return false;
    }




    /** Get the toolkit from an Office which can then be used to register
        the listener.
    */
    private XExtendedToolkit getToolkit ()
    {
        // Connect to Office.
        XMultiServiceFactory xFactory = connectToOffice (msHostName, mnPortNumber);

        // Get toolkit.
        XExtendedToolkit xToolkit = null;
        try
        {
            if (xFactory != null)
            {
                xToolkit = (XExtendedToolkit) UnoRuntime.queryInterface(
                    XExtendedToolkit.class,
                    xFactory.createInstance ("stardiv.Toolkit.VCLXToolkit"));
            }
        }
        catch (com.sun.star.uno.Exception aException)
        {
            MessageArea.println ("caught exception while creating extended toolkit");
            // Ignored.
        }

        return xToolkit;
    }




    /** Connect to a running (Star|Open)Office application that has
        been started with a command line argument like
        "-accept=socket,host=localhost,port=5678;urp;"
    */
    private XMultiServiceFactory connectToOffice (String hostname, int portnumber)
    {
        //  Set up connection string.
        String sConnectString = "uno:socket,host=" + hostname + ",port=" + portnumber
                + ";urp;StarOffice.ServiceManager";


        // connect to a running office and get the ServiceManager
        try
        {
            //  Create a URL Resolver.
            XMultiServiceFactory aLocalServiceManager =
                    com.sun.star.comp.helper.Bootstrap.createSimpleServiceManager();
            XUnoUrlResolver aURLResolver = (XUnoUrlResolver) UnoRuntime.queryInterface (
                XUnoUrlResolver.class,
                aLocalServiceManager.createInstance ("com.sun.star.bridge.UnoUrlResolver")
                );
            return (XMultiServiceFactory) UnoRuntime.queryInterface (
                XMultiServiceFactory.class,
                aURLResolver.resolve (sConnectString));
        }

        catch (Exception e)
        {
            if ( ! mbInitialized)
            {
                MessageArea.println ("Could not connect to office");
                MessageArea.println ("Please start OpenOffice/StarOffice with "
                    + "\"-accept=socket,host=" + msHostName
                    +",port=" + mnPortNumber
                    + ";urp;\"");
            }
            else
                MessageArea.print (".");
        }
        mbInitialized = true;
        return null;
    }



    /// Default port number.
    private int mnPortNumber = 8100;

    /// Default host name.
    private String msHostName = "localhost";

    /** Time in milliseconds between two attempts to connect to an Office
         application.
    */
    private int mnPeriod = 1000;

    private EventListenerProxy mxListener;
    private boolean mbInitialized;

    /** This timer is used for the registration loop to retry to connect to
        the Office until a connection can be established.
    */
    private java.util.Timer maTimer;
}