package com.temp.client.foundation.pavment;

import com.google.gwt.place.shared.*;
import com.temp.client.foundation.pavment.PlaceChanger.*;

/**
 * Simple Activity implementation that is always willing to stop, and does
 * nothing onStop and onCancel.
 */
public abstract class AbstractActivity implements Activity,
                                                  ForcedPlaceChanger {
    private final PlaceChanger placeChanger;

    public AbstractActivity( PlaceChanger placeChanger ) {
        this.placeChanger = placeChanger;
    }

    @Override
    public final void goTo( Place place ) {
        GoToPlace response = placeChanger.goTo( place );
        if ( response != null ) {
            switch ( response ) {
                case AlreadyThere:
                    refresh();
                    break;
                default: // Huh?
                    break;
                case NoActivity: // should have been Notified by PAM
                    break;
                case CurrentActivityRejectedLeaving: // should have been notified by current activity
                    break;
            }
        }
    }

    /**
     * Returns the current place.
     *
     * @return a {@link Place} instance
     */
    @Override
    public final Place getWhere() {
        return placeChanger.getWhere();
    }

    @Override
    public String mayStop() {
        return null;
    }

    @Override
    public void onCancel() {
    }

    @Override
    public void onStop() {
    }
}