/**********************************************
    * 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.dnd;
  
  import java.util.ArrayList;
  import java.util.List;
  
  import org.vectomatic.dom.svg.OMSVGElement;
  import org.vectomatic.dom.svg.itf.ISVGTransformable;
  import org.vectomatic.dom.svg.utils.SVGConstants;
  import org.vectomatic.svg.edit.client.command.CommandFactories;
  import org.vectomatic.svg.edit.client.command.DndCommandFactory.DropGesture;
  import org.vectomatic.svg.edit.client.engine.SVGModel;
  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.data.BeanModel;
  import com.extjs.gxt.ui.client.data.BeanModelLookup;
  import com.extjs.gxt.ui.client.util.Format;
  
  /**
   * Class to represent a tree cloning command
   * @author laaglu
   */
  public class CloneCommand extends DndCommandBase {
  	/**
  	 * The models to copy, unsorted
  	 */
  	protected List<SVGElementModel> models;
  	/**
  	 * The cloned models, unsorted
  	 */
  	protected List<SVGElementModel> clones;
  	/**
  	 * The target model
  	 */
  	protected SVGElementModel target;
  	/**
  	 * The drop gesture
  	 */
  	protected DropGesture dropGesture;
  	
  	public CloneCommand(List<SVGElementModel> models, SVGElementModel target, DropGesture dropGesture) {
  		super(CommandFactories.getDndCommandFactory());
  		this.models = models;
  		this.target = target;
  		this.dropGesture = dropGesture;
  		for (SVGElementModel model : models) {
  			assert model.getOwner() == target.getOwner() : "Attempt to copy models from heterogeneous owners: " + model.getOwner() + ", " + target.getOwner();
  		}
  	}
  
  	@Override
  	public String getDescription() {
  		String message = null;
  		switch(dropGesture) {
  			case OnNode:
  				message = ModelConstants.INSTANCE.dndCloneCmdIn();
  				break;
  			case BeforeNode:
  				message = ModelConstants.INSTANCE.dndCloneCmdBefore();
  				break;
  			case AfterNode:
  				message = ModelConstants.INSTANCE.dndCloneCmdAfter();
  				break;
  		}
  		return Format.substitute(message, SVGNamedElementModel.getNames(models), target.toString());
  	}
  
  	@Override
  	public void commit() {
  		SVGModel owner = target.getOwner();
  		if (clones == null) {
  			clones = new ArrayList<SVGElementModel>();
  			for (SVGElementModel model : models) {
  				SVGElementModel clone = owner.clone(model, Format.substitute(ModelConstants.INSTANCE.copyOf(), model.get(SVGConstants.SVG_TITLE_TAG).toString()));
  				clones.add(clone);
  			}
  		}
  		SVGElementModel parentModel = null;
  		SVGElementModel refModel = null;
  		if (dropGesture == DropGesture.OnNode) {
  			// target is a folder
 			parentModel = target;
 		} else {
 			// target is a leaf in the same document
 			parentModel = (SVGElementModel) target.getParent();
 			if (dropGesture == DropGesture.BeforeNode) {
 				refModel = target;
 			} else if (dropGesture == DropGesture.AfterNode) {
 				refModel = target.getNextSibling();
 			}
 		}
 		
 		OMSVGElement parentElement = parentModel.getElementWrapper();
 		for (int i = 0, size = models.size(); i < size; i++) {
 			SVGElementModel model = models.get(i);
 			SVGElementModel clone = clones.get(i);
 
 			// Update the transform of a model which is going to be
 			// attached to a parent model so that the model appears 
 			// unchanged to the end-user. This is done by applying
 			// a counter transform (the inverse of the transform
 			// of the parent) to to nullify its effect
 			OMSVGElement element = model.getElementWrapper();
 			clone.updateTransform(((ISVGTransformable)element).getTransformToElement(parentElement));
 
 			owner.insertBefore(parentModel, clone, refModel);
 		}
 
 	}
 
 	@Override
 	public void rollback() {
 		SVGModel owner = target.getOwner();
 		for (SVGElementModel clone : clones) {
 			owner.remove(clone);
 		}
 	}
 
 	@Override
 	public BeanModel asModel() {
 		return BeanModelLookup.get().getFactory(CloneCommand.class).createModel(this);
 	}
 
 }