/**
    * Copyright 2011 The Kuali Foundation Licensed under the
    * Educational Community License, Version 2.0 (the "License"); you may
    * not use this file except in compliance with the License. You may
    * obtain a copy of the License at
    *
    * http://www.osedu.org/licenses/ECL-2.0
    *
    * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an "AS IS"
   * BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
   * or implied. See the License for the specific language governing
   * permissions and limitations under the License.
   */
  
  package org.kuali.mobility.file.dao;
  
  import org.kuali.mobility.file.entity.File;
  import org.springframework.stereotype.Repository;
  
  import javax.persistence.EntityManager;
  import javax.persistence.OptimisticLockException;
  import javax.persistence.PersistenceContext;
  import javax.persistence.Query;
  import java.util.List;
  
  @Repository
  public class FileDaoImpl implements FileDao {
  
  	private static org.apache.log4j.Logger LOG = org.apache.log4j.Logger.getLogger(FileDaoImpl.class);		
  	private String ME = this.getClass().getName();
  	
  	@PersistenceContext
      private EntityManager entityManager;
  	
      public FileDaoImpl(){}
      
  	public Long saveFile(File file){
  		if(file == null){
      		return null;
      	}
      	try {
  			if(file.getId() == null){
  				entityManager.persist(file);
  			}else{
  				entityManager.merge(file);
  			}
  		} catch (OptimisticLockException e) {
  			return null;
  		}
      	return file.getId();
  	}
  
  	public boolean removeFile(File file){
  		boolean result = true;
  		if(file == null){
  			return false;
  		}
  		if(file.getId() != null){
  			try{
  				File f = entityManager.find(File.class, file.getId());
  				entityManager.remove(f);
  			}catch(Exception e){
      			LOG.info("Exception Caught: " + e.getMessage());
  				result = false;
  			}
  		}
  		return result;
  	}
  	
      @SuppressWarnings("unchecked")
  	public File findFileById(Long Id){
          Query query = entityManager.createQuery("select f from File f where f.id = " + Id);
          return (File) query.getSingleResult();
  	}
  	
      @SuppressWarnings("unchecked")
  	public List<File> findFilesByName(String name){
          Query query = entityManager.createQuery("select f from File f where f.fileName like '" + name + "'");
          return query.getResultList();
  	}
  
      @SuppressWarnings("unchecked")
  	public List<File> findAllFiles(){
      	
      	Query query = entityManager.createQuery("select f from File f order by f.postedTimestamp desc");
          return query.getResultList();
  	}
      
      public EntityManager getEntityManager() {
          return entityManager;
      }
  
      public void setEntityManager(EntityManager entityManager) {
          this.entityManager = entityManager;
      }	
  }