package org.itracker.persistence.dao;
   
   import java.util.Date;
   
   import org.hibernate.HibernateException;
   import org.itracker.model.Entity;
   import org.springframework.dao.InvalidDataAccessResourceUsageException;
   import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
   
  /**
   * Contains common behaviour to all hibernate factories
   * 
   * @author rui silva
   */
  public abstract class BaseHibernateDAOImpl<T extends Entity> extends HibernateDaoSupport 
          implements BaseDAO<T> {
  
      /**
       * 
       */
      public BaseHibernateDAOImpl() {
          super();
      }
  
      /**
       * insert a new entity.
       * create- and lastmodified-date is set with current time.
       * 
       * @param entity - detached entity object
       */
      public void save(T entity) {
      	if (null == entity) {
      		throw new InvalidDataAccessResourceUsageException( "entity must not be null" );
      	}
          try {
          	Date createDate = new Date();
          	entity.setCreateDate(createDate);
          	entity.setLastModifiedDate(createDate);
              getSession().save(entity);
          } catch (HibernateException ex) {
          	logger.debug("save: caught HibernateException, call to convertHibernateException", ex);
              throw convertHibernateAccessException(ex);
          }
      }
  
      /**
       * inserts a new detached entity or updates if it already exists.
       * create- and update-date are set automatically.
       * 
       * @param entity - entity object to be inserted or updated
       */
      public void saveOrUpdate(T entity) {
      	if (null == entity) {
      		throw new InvalidDataAccessResourceUsageException( "entity must not be null" );
      	}
  
          try {
          	if (null == entity.getCreateDate()){
          		entity.setCreateDate(new Date());
          		entity.setLastModifiedDate(entity.getCreateDate());
          	} else {
          		entity.setLastModifiedDate(new Date());
          	}
              getSession().saveOrUpdate(entity);
          } catch (HibernateException ex) {
          	logger.debug("saveOrUpdate: caught HibernateException, call to convertHibernateException", ex);
              throw convertHibernateAccessException(ex);
          }
      }
  
      public void delete(T entity) {
          if (null == entity) {
      		throw new InvalidDataAccessResourceUsageException( "entity must not be null" );
      	}
          try {
              getSession().delete(entity);
              getSession().flush();
          } catch (HibernateException ex) {
          	logger.debug("delete: caught HibernateException, call to convertHibernateException", ex);
              throw convertHibernateAccessException(ex);
          }    
      }
  
      public void detach(T entity) {
      	if (null == entity) {
      		throw new InvalidDataAccessResourceUsageException( "entity must not be null" );
      	}
      	try {
      		getSession().evict(entity);
          } catch (HibernateException ex) {
          	logger.debug("detach: caught HibernateException, call to convertHibernateException", ex);
              throw convertHibernateAccessException(ex);
          }    
      }
      
      public void refresh(T entity) {
      	if (null == entity) {
      		throw new InvalidDataAccessResourceUsageException( "entity must not be null" );
      	}
     	try {
     		getSession().refresh(entity);
         } catch (HibernateException ex) {
         	logger.debug("refresh: caught HibernateException, call to convertHibernateException", ex);
             throw convertHibernateAccessException(ex);
         }    
     }
     
     @SuppressWarnings("unchecked")
 	public T merge(T entity) {
     	if (null == entity) {
     		throw new InvalidDataAccessResourceUsageException( "entity must not be null" );
     	}
     	try {
     		return (T)getSession().merge(entity);
         } catch (HibernateException ex) {
         	logger.debug("merge: caught HibernateException, call to convertHibernateException", ex);
             throw convertHibernateAccessException(ex);
         }    
     }
 }