/***********************************************************************
 * Copyright (c) 2008 by SAP AG, Walldorf. 
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     SAP AG - initial API and implementation
 ***********************************************************************/
package org.eclipse.jst.jee.model.internal.mergers;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.emf.ecore.EObject;
import org.eclipse.emf.ecore.util.EcoreUtil;
import org.eclipse.jst.javaee.core.PersistenceUnitRef;

/**
 * 
 * Merges persistence unit references artifacts.
 * 
 * @author Dimitar Giormov
 */

public class PersistenceUnitRefsMerger extends BaseRefsMerger {
	
  /**
   *  Constructor for the class. 
   * 
   * @param base - base list with persistence unit references.
   *               that have higher priority and are result of the merge. 
   * @param toMerge - toMerge list to be imported in base list.
   */
	public PersistenceUnitRefsMerger(List base, List toMerge) {
        super(base, toMerge);
    }

    /* (non-Javadoc)
     * @see org.eclipse.jst.javaee.ejb.model.mergers.common.ModelElementsMerger#process()
     */
    public List process() throws ModelException {
      List warnings = new ArrayList();
      for (Object oToMerge : getToMergeElemets()) {
          PersistenceUnitRef resRef = (PersistenceUnitRef) oToMerge;
          boolean found = false;
          for (Object oBase : getBaseElements()) {
            PersistenceUnitRef resRefBase = (PersistenceUnitRef) oBase;
              if (resRefBase.getPersistenceUnitRefName().equals(resRef.getPersistenceUnitRefName())){
                  copyMissingPropertesInBase(resRefBase, resRef);
                  found = true;
                  break;
              }
          }
          if (found){
              continue;
          }
          getBaseElements().add(EcoreUtil.copy((EObject) oToMerge));
      }
      return warnings;
    }
    
    
    protected void copyMissingPropertesInBase(PersistenceUnitRef baseElement, PersistenceUnitRef toMergeElement) {    	
    	if(baseElement.getPersistenceUnitName() == null){
    		baseElement.setPersistenceUnitName(toMergeElement.getPersistenceUnitName());
    	}
    	if(baseElement.getMappedName() == null){
          baseElement.setMappedName(toMergeElement.getMappedName());
      }
    }
    
    
    protected void copyMissingPropertesInBase(Object base, Object toMerge){
    	copyMissingPropertesInBase((PersistenceUnitRef) base, (PersistenceUnitRef) toMerge);
    }
    
}