/**********************************************
    * Copyright (C) 2011 Lukas Laag
    * This file is part of svgreal.
    * 
    * svgreal 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, or
    * (at your option) any later version.
    * 
   * svgreal 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 svgreal.  If not, see http://www.gnu.org/licenses/
   **********************************************/
  package org.vectomatic.svg.edit.client.command;
  
  import java.util.List;
  
  import org.vectomatic.svg.edit.client.SvgrealApp;
  import org.vectomatic.svg.edit.client.engine.SVGModel;
  import org.vectomatic.svg.edit.client.event.SelectionChangedProcessor;
  import org.vectomatic.svg.edit.client.gxt.widget.CommandFactoryMenuItem;
  import org.vectomatic.svg.edit.client.model.ModelConstants;
  import org.vectomatic.svg.edit.client.model.svg.SVGElementModel;
  import org.vectomatic.svg.edit.client.model.svg.SVGNamedElementModel;
  
  import com.extjs.gxt.ui.client.event.SelectionChangedEvent;
  import com.extjs.gxt.ui.client.util.Format;
  import com.google.gwt.core.client.GWT;
  
  /**
   * Command factory to build commands which remove elements from the model
   * @author laaglu
   */
  public class RemoveElementsCommandFactory extends CommandFactoryBase implements SelectionChangedProcessor<SVGElementModel> {
  	@SuppressWarnings("serial")
  	public static final IFactoryInstantiator<RemoveElementsCommandFactory> INSTANTIATOR = new FactoryInstantiatorBase<RemoveElementsCommandFactory>(ModelConstants.INSTANCE.removeElementsCmdFactory(), ModelConstants.INSTANCE.removeElementsCmdFactoryDesc()) {
  		@Override
  		public RemoveElementsCommandFactory create() {
  			return new RemoveElementsCommandFactory();
  		}
  	};
  
  	@Override
  	public IFactoryInstantiator<?> getInstantiator() {
  		return INSTANTIATOR;
  	}
  
  	@Override
  	public void start(Object requester) {
  		GWT.log("RemoveElementsCommandFactory.start(" + requester + ")");
  		SVGModel svgModel = SvgrealApp.getApp().getActiveModel();
  		if (requester instanceof SVGModel || requester instanceof CommandFactoryMenuItem) {
  			// The request comes from the DEL key or the context menu.
  			// Erase the elements, but do not push the factory on the stack.
  			createCommand(svgModel);
  			return;
  		} 
  		super.start(requester);
  
  		// The request comes from the command factory combo
  		// Clear the selection and listen to selection events
  		if (svgModel != null) {
  			svgModel.getSelectionModel().deselectAll();
  		}
  		
  		// Become the target command factory.
  		updateStatus(ModelConstants.INSTANCE.removeElementsCmdFactory1());
  	}
  
  	@Override
  	public boolean processSelectionChanged(SelectionChangedEvent<SVGElementModel> se) {
  		List<SVGElementModel> models = se.getSelection();
  		GWT.log("RemoveElementsCommandFactory.processSelectionChanged: " + models);
  		if (models.size() > 0) {
  			createCommand(models.get(0).getOwner());
  			return true;
  		}
  		return false;
  	}
  	
  	private void createCommand(SVGModel svgModel) {
  		GWT.log("RemoveElementsCommandFactory.createCommand(" + svgModel + ")");
  		if (svgModel != null) {
  			List<SVGElementModel> models = svgModel.getSelectionModel().getSelectedItems();
  			// Prevent the viewBox from being removed
  			models.remove(svgModel.getViewBox());
  			if (models.size() > 0) {
  				GenericRemoveCommand command = new GenericRemoveCommand(this, models, Format.substitute(ModelConstants.INSTANCE.removeCmd(), SVGNamedElementModel.getNames(models)));
  				command.commit();
  				svgModel.getCommandStore().addCommand(command);
  			}
  		}
  	}
  }