package org.jtheque.primary.view.impl.models;

 /*

  * This file is part of JTheque.

  *

  * JTheque is free software: you can redistribute it and/or modify

  * it under the terms of the GNU General Public License as published by

  * the Free Software Foundation, either version 3 of the License.

  *

  * JTheque is distributed in the hope that it will be useful,

  * but WITHOUT ANY WARRANTY; without even the implied warranty of

  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

  * GNU General Public License for more details.

  *

  * You should have received a copy of the GNU General Public License

  * along with JTheque.  If not, see <http://www.gnu.org/licenses/>.

  */

 import org.jdesktop.swingx.event.WeakEventListenerList;

 import org.jtheque.primary.od.able.Data;

 import org.jtheque.primary.view.impl.listeners.CurrentObjectListener;

 import org.jtheque.primary.view.impl.listeners.DisplayListListener;

 import org.jtheque.primary.view.impl.listeners.ObjectChangedEvent;

 import org.jtheque.primary.view.impl.models.able.IPrincipalDataModel;

 import java.util.Collection;

 /**

  * A model for the principal data.

  *

  * @author Baptiste Wicht

  */

 public abstract class PrincipalDataModel<T extends Data> implements IPrincipalDataModel<T> {

         private final WeakEventListenerList listenerList;

         private Collection<T> displayList;

         /**

          * Construct a new PrincipalDataModel.

          */

         protected PrincipalDataModel(){

                 super();

                 listenerList = new WeakEventListenerList();

         }

         /**

          * Return the datas managed by this model.

          *

          * @return The datas managed by this model.

          */

         public abstract Collection<T> getDatas();

         /**

          * Return the event listener list.

          *

          * @return The event listener list.

          */

         protected final WeakEventListenerList getEventListenerList(){

                 return listenerList;

         }

         @Override

         public final void addCurrentObjectListener(CurrentObjectListener listener){

                 listenerList.add(CurrentObjectListener.class, listener);

         }

         @Override

         public final void addDisplayListListener(DisplayListListener listener){

                 listenerList.add(DisplayListListener.class, listener);

         }

         /**

          * Fire an event to say that the current object has changed.

          *

          * @param event The event to fire

          */

         protected final void fireCurrentObjectChanged(ObjectChangedEvent event){

                 CurrentObjectListener[] listeners = listenerList.getListeners(CurrentObjectListener.class);

                 for (CurrentObjectListener listener : listeners){

                         listener.objectChanged(event);

                 }

         }

         /**

          * Avert the listeners that the display list have changed.

          */

         protected final void fireDisplayListChanged(){

                 DisplayListListener[] listeners = listenerList.getListeners(DisplayListListener.class);

                 for (DisplayListListener listener : listeners){

                         listener.displayListChanged();

                 }

         }

         @Override

         public final Collection<T> getDisplayList(){

                 if (displayList == null){

                         displayList = getDatas();

                 }

                 return displayList;

         }

         @Override

         public final void updateDisplayList(Collection<T> datas){

                 getDisplayList().clear();

                 if (datas != null){

                         getDisplayList().addAll(datas);

                 } else {

                         getDisplayList().addAll(getDatas());

                 }

                 fireDisplayListChanged();

         }

         @Override

         public final void dataChanged(){

                 updateDisplayList();

         }

         /**

          * Update the display list.

          */

         public final void updateDisplayList(){

                 updateDisplayList(null);

         }

 }