EDIT

/**

* Copyright (C) 2007 EDIT

* European Distributed Institute of Taxonomy

* http://www.e-taxonomy.eu

*

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.cdm.persistence.dao.hibernate.common;

import java.lang.reflect.Field;

import java.util.ArrayList;

import java.util.Collection;

import java.util.HashMap;

import java.util.Iterator;

import java.util.List;

import java.util.Map;

import java.util.Set;

import java.util.UUID;

import org.apache.log4j.Logger;

import org.apache.lucene.search.Sort;

import org.apache.lucene.search.SortField;

import org.apache.lucene.util.Version;

import org.hibernate.Criteria;

import org.hibernate.HibernateException;

import org.hibernate.LockMode;

import org.hibernate.NonUniqueObjectException;

import org.hibernate.Query;

import org.hibernate.Session;

import org.hibernate.criterion.Criterion;

import org.hibernate.criterion.DetachedCriteria;

import org.hibernate.criterion.Example;

import org.hibernate.criterion.Example.PropertySelector;

import org.hibernate.criterion.Order;

import org.hibernate.criterion.ProjectionList;

import org.hibernate.criterion.Projections;

import org.hibernate.criterion.Restrictions;

import org.hibernate.envers.query.AuditQuery;

import org.hibernate.metadata.ClassMetadata;

import org.hibernate.search.FullTextQuery;

import org.hibernate.type.Type;

import org.joda.time.DateTime;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.dao.DataAccessException;

import org.springframework.dao.InvalidDataAccessApiUsageException;

import org.springframework.security.core.Authentication;

import org.springframework.security.core.context.SecurityContextHolder;

import org.springframework.stereotype.Repository;

import org.springframework.util.ReflectionUtils;

import eu.etaxonomy.cdm.config.Configuration;

import eu.etaxonomy.cdm.model.common.CdmBase;

import eu.etaxonomy.cdm.model.common.User;

import eu.etaxonomy.cdm.model.common.VersionableEntity;

import eu.etaxonomy.cdm.persistence.dao.common.ICdmEntityDao;

import eu.etaxonomy.cdm.persistence.dao.initializer.IBeanInitializer;

import eu.etaxonomy.cdm.persistence.hibernate.replace.ReferringObjectMetadata;

import eu.etaxonomy.cdm.persistence.hibernate.replace.ReferringObjectMetadataFactory;

import eu.etaxonomy.cdm.persistence.query.Grouping;

import eu.etaxonomy.cdm.persistence.query.MatchMode;

import eu.etaxonomy.cdm.persistence.query.OrderHint;

/**

 * @author a.mueller

 * FIXME CdmEntityDaoBase is abstract, can it be annotated with @Repository?

 */

@Repository

public abstract class CdmEntityDaoBase<T extends CdmBase> extends DaoBase implements ICdmEntityDao<T> {

    private static final Logger logger = Logger.getLogger(CdmEntityDaoBase.class);

    protected int flushAfterNo = 1000; //large numbers may cause synchronisation errors when commiting the session !!

    protected Class<T> type;

    protected Version version = Configuration.luceneVersion;

    @Autowired

//	@Qualifier("defaultBeanInitializer")

    protected IBeanInitializer defaultBeanInitializer;

    public void setDefaultBeanInitializer(IBeanInitializer defaultBeanInitializer) {

        this.defaultBeanInitializer = defaultBeanInitializer;

    }

    @Autowired

    private ReferringObjectMetadataFactory referringObjectMetadataFactory;

    public CdmEntityDaoBase(Class<T> type){

        this.type = type;

        logger.debug("Creating DAO of type [" + type.getSimpleName() + "]");

    }

    @Override

    public void lock(T t, LockMode lockMode) {

        getSession().lock(t, lockMode);

    }

    @Override

    public void refresh(T t, LockMode lockMode, List<String> propertyPaths) {

        getSession().refresh(t, lockMode);

        defaultBeanInitializer.initialize(t, propertyPaths);

    }

    //TODO this method should be moved to a concrete class (not typed)

    public UUID saveCdmObj(CdmBase cdmObj) throws DataAccessException  {

        getSession().saveOrUpdate(cdmObj);

        return cdmObj.getUuid();

    }

    //TODO: Replace saveCdmObj() by saveCdmObject_

    private UUID saveCdmObject_(T cdmObj){

        getSession().saveOrUpdate(cdmObj);

        return cdmObj.getUuid();

    }

    //TODO: Use everywhere CdmEntityDaoBase.saveAll() instead of ServiceBase.saveCdmObjectAll()?

    //TODO: why does this use saveCdmObject_ which actually savesOrUpdateds data ?

    @Override

    public Map<UUID, T> saveAll(Collection<T> cdmObjCollection){

        int types = cdmObjCollection.getClass().getTypeParameters().length;

        if (types > 0){

            if (logger.isDebugEnabled()){logger.debug("ClassType: + " + cdmObjCollection.getClass().getTypeParameters()[0]);}

        }

        Map<UUID, T> resultMap = new HashMap<UUID, T>();

        Iterator<T> iterator = cdmObjCollection.iterator();

        int i = 0;

        while(iterator.hasNext()){

            if ( ( (i % 2000) == 0) && (i > 0)   ){logger.debug("Saved " + i + " objects" );}

            T cdmObj = iterator.next();

            UUID uuid = saveCdmObject_(cdmObj);

            if (logger.isDebugEnabled()){logger.debug("Save cdmObj: " + (cdmObj == null? null: cdmObj.toString()));}

            resultMap.put(uuid, cdmObj);

            i++;

            if ( (i % flushAfterNo) == 0){

                try{

                    if (logger.isDebugEnabled()){logger.debug("flush");}

                    flush();

                }catch(Exception e){

                    logger.error("An exception occurred when trying to flush data");

                    e.printStackTrace();

                    throw new RuntimeException(e);

                }

            }

        }

        if ( logger.isInfoEnabled() ){logger.info("Saved " + i + " objects" );}

        return resultMap;

    }

    private UUID saveOrUpdateCdmObject(T cdmObj){

        getSession().saveOrUpdate(cdmObj);

        return cdmObj.getUuid();

    }

    @Override

    public Map<UUID, T> saveOrUpdateAll(Collection<T> cdmObjCollection){

        int types = cdmObjCollection.getClass().getTypeParameters().length;

        if (types > 0){

            if (logger.isDebugEnabled()){logger.debug("ClassType: + " + cdmObjCollection.getClass().getTypeParameters()[0]);}

        }

        Map<UUID, T> resultMap = new HashMap<UUID, T>();

        Iterator<T> iterator = cdmObjCollection.iterator();

        int i = 0;

        while(iterator.hasNext()){

            if ( ( (i % 2000) == 0) && (i > 0)   ){logger.debug("Saved " + i + " objects" );}

            T cdmObj = iterator.next();

            UUID uuid = saveOrUpdateCdmObject(cdmObj);

            if (logger.isDebugEnabled()){logger.debug("Save cdmObj: " + (cdmObj == null? null: cdmObj.toString()));}

            resultMap.put(uuid, cdmObj);

            i++;

            if ( (i % flushAfterNo) == 0){

                try{

                    if (logger.isDebugEnabled()){logger.debug("flush");}

                    flush();

                }catch(Exception e){

                    logger.error("An exception occurred when trying to flush data");

                    e.printStackTrace();

                    throw new RuntimeException(e);

                }

            }

        }

        if ( logger.isInfoEnabled() ){logger.info("Saved " + i + " objects" );}

        return resultMap;

    }

    @Override

    public T replace(T x, T y) {

        if(x.equals(y)) {

            return y;

        }

        Class commonClass = x.getClass();

        if(y != null) {

            while(!commonClass.isAssignableFrom(y.getClass())) {

                if(commonClass.equals(type)) {

                    throw new RuntimeException();

                }

                commonClass = commonClass.getSuperclass();

            }

        }

        getSession().merge(x);

        Set<ReferringObjectMetadata> referringObjectMetas = referringObjectMetadataFactory.get(x.getClass());

        for(ReferringObjectMetadata referringObjectMetadata : referringObjectMetas) {

          List<CdmBase> referringObjects = referringObjectMetadata.getReferringObjects(x, getSession());

          for(CdmBase referringObject : referringObjects) {

            try {

                referringObjectMetadata.replace(referringObject,x,y);

                getSession().update(referringObject);

            } catch (IllegalArgumentException e) {

                throw new RuntimeException(e.getMessage(),e);

            } catch (IllegalAccessException e) {

                throw new RuntimeException(e.getMessage(),e);

            }

          }

        }

        return y;

    }

    @Override

    public Session getSession() throws DataAccessException {

        return super.getSession();

    }

    @Override

    public void clear() throws DataAccessException {

        Session session = getSession();

        session.clear();

        if (logger.isDebugEnabled()){logger.debug("dao clear end");}

    }

    @Override

    public T merge(T transientObject) throws DataAccessException {

        Session session = getSession();

        T persistentObject = (T)session.merge(transientObject);

        if (logger.isDebugEnabled()){logger.debug("dao merge end");}

        return persistentObject;

    }

    @Override

    public UUID saveOrUpdate(T transientObject) throws DataAccessException  {

        if (transientObject == null){

        	logger.warn("Object to save should not be null. NOP");

        	return null;

        }

    	try {

            if (logger.isDebugEnabled()){logger.debug("dao saveOrUpdate start...");}

            if (logger.isDebugEnabled()){logger.debug("transientObject(" + transientObject.getClass().getSimpleName() + ") ID:" + transientObject.getId() + ", UUID: " + transientObject.getUuid()) ;}

            Session session = getSession();

            if(transientObject.getId() != 0 && VersionableEntity.class.isAssignableFrom(transientObject.getClass())) {

                VersionableEntity versionableEntity = (VersionableEntity)transientObject;

                versionableEntity.setUpdated(new DateTime());

                Authentication authentication = SecurityContextHolder.getContext().getAuthentication();

                if(authentication != null && authentication.getPrincipal() != null && authentication.getPrincipal() instanceof User) {

                  User user = (User)authentication.getPrincipal();

                  versionableEntity.setUpdatedBy(user);

                }

            }

            session.saveOrUpdate(transientObject);

            if (logger.isDebugEnabled()){logger.debug("dao saveOrUpdate end");}

            return transientObject.getUuid();

        } catch (NonUniqueObjectException e) {

            logger.error("Error in CdmEntityDaoBase.saveOrUpdate(obj)");

            logger.error(e.getIdentifier());

            logger.error(e.getEntityName());

            logger.error(e.getMessage());

            e.printStackTrace();

            throw e;

        } catch (HibernateException e) {

            e.printStackTrace();

            throw e;

        }

    }

    @Override

    public UUID save(T newInstance) throws DataAccessException {

        if (newInstance == null){

        	logger.warn("Object to save should not be null. NOP");

        	return null;

        }

    	getSession().save(newInstance);

        return newInstance.getUuid();

    }

    @Override

    public UUID update(T transientObject) throws DataAccessException {

        if (transientObject == null){

        	logger.warn("Object to update should not be null. NOP");

        	return null;

        }

    	getSession().update(transientObject);

        return transientObject.getUuid();

    }

    @Override

    public UUID refresh(T persistentObject) throws DataAccessException {

        getSession().refresh(persistentObject);

        return persistentObject.getUuid();

    }

    @Override

    public UUID delete(T persistentObject) throws DataAccessException {

        if (persistentObject == null){

            logger.warn(type.getName() + " was 'null'");

            return null;

        }

        // Merge the object in if it is detached

        //

        // I think this is preferable to catching lazy initialization errors

        // as that solution only swallows and hides the exception, but doesn't

        // actually solve it.

        getSession().merge(persistentObject);

        getSession().delete(persistentObject);

        return persistentObject.getUuid();

    }

    @Override

    public T findById(int id) throws DataAccessException {

        return (T) getSession().get(type, id);

    }

    @Override

    public T findByUuid(UUID uuid) throws DataAccessException{

        Session session = getSession();

        Criteria crit = session.createCriteria(type);

        crit.add(Restrictions.eq("uuid", uuid));

        crit.addOrder(Order.desc("created"));

        List<T> results = crit.list();

        if (results.isEmpty()){

            return null;

        }else{

            if(results.size() > 1){

                logger.error("findByUuid() delivers more than one result for UUID: " + uuid);

            }

            return results.get(0);

        }

    }

    @Override

    public List<T> listByIds(Collection<Integer> ids,  Integer pageSize, Integer pageNumber, List<OrderHint> orderHints, List<String> propertyPaths) throws DataAccessException {

        if (ids.isEmpty()) {

            return new ArrayList<T>(0);

        }

        Criteria criteria = prepareList(ids, pageSize, pageNumber, orderHints, "id");

        logger.debug(criteria.toString());

         List<T> result = criteria.list();

         defaultBeanInitializer.initializeAll(result, propertyPaths);

         return result;

     }

    @Override

    public List<T> list(Collection<UUID> uuids, Integer pageSize, Integer pageNumber, List<OrderHint> orderHints, List<String> propertyPaths) throws DataAccessException {

       Criteria criteria = prepareList(uuids, pageSize, pageNumber, orderHints, "uuid");

        List<T> result = criteria.list();

        defaultBeanInitializer.initializeAll(result, propertyPaths);

        return result;

    }

    /**

     * @param uuids

     * @param pageSize

     * @param pageNumber

     * @param orderHints

     * @param propertyName

     * @return

     */

    private Criteria prepareList(Collection<?> uuids, Integer pageSize, Integer pageNumber, List<OrderHint> orderHints, String propertyName) {

        Criteria criteria = getSession().createCriteria(type);

        criteria.add(Restrictions.in(propertyName, uuids));

        if(pageSize != null) {

            criteria.setMaxResults(pageSize);

            if(pageNumber != null) {

                criteria.setFirstResult(pageNumber * pageSize);

            } else {

                criteria.setFirstResult(0);

            }

        }

        if(orderHints == null) {

            orderHints = OrderHint.defaultOrderHintsFor(type);

        }

        addOrder(criteria, orderHints);

        return criteria;

    }

    protected List<T> findByParam(Class<? extends T> clazz, String param, String queryString, MatchMode matchmode, List<Criterion> criterion, Integer pageSize, Integer pageNumber, List<OrderHint> orderHints, List<String> propertyPaths) {

        Criteria criteria = null;

        if(clazz == null) {

            criteria = getSession().createCriteria(type);

        } else {

            criteria = getSession().createCriteria(clazz);

        }

        if (queryString != null) {

            if(matchmode == null) {

                criteria.add(Restrictions.ilike(param, queryString));

            } else if(matchmode == MatchMode.BEGINNING) {

                criteria.add(Restrictions.ilike(param, queryString, org.hibernate.criterion.MatchMode.START));

            } else if(matchmode == MatchMode.END) {

                criteria.add(Restrictions.ilike(param, queryString, org.hibernate.criterion.MatchMode.END));

            } else if(matchmode == MatchMode.EXACT) {

                criteria.add(Restrictions.ilike(param, queryString, org.hibernate.criterion.MatchMode.EXACT));

            } else {

                criteria.add(Restrictions.ilike(param, queryString, org.hibernate.criterion.MatchMode.ANYWHERE));

            }

        }

        addCriteria(criteria, criterion);

        if(pageSize != null) {

            criteria.setMaxResults(pageSize);

            if(pageNumber != null) {

                criteria.setFirstResult(pageNumber * pageSize);

            } else {

                criteria.setFirstResult(0);

            }

        }

        addOrder(criteria, orderHints);

        List<T> result = criteria.list();

        defaultBeanInitializer.initializeAll(result, propertyPaths);

        return result;

    }

    @Override

    public T load(UUID uuid) {

        T bean = findByUuid(uuid);

        if(bean == null){

            return null;

        }

        defaultBeanInitializer.load(bean);

        return bean;

    }

    @Override

    public T load(int id, List<String> propertyPaths){

        T bean = findById(id);

        if(bean == null){

            return bean;

        }

        defaultBeanInitializer.initialize(bean, propertyPaths);

        return bean;

    }

    @Override

    public T load(UUID uuid, List<String> propertyPaths){

        T bean = findByUuid(uuid);

        if(bean == null){

            return bean;

        }

        defaultBeanInitializer.initialize(bean, propertyPaths);

        return bean;

    }

    @Override

    public Boolean exists(UUID uuid) {

        if (findByUuid(uuid)==null){

            return false;

        }

        return true;

    }

    @Override

    public int count() {

        return count(type);

    }

    @Override

    public int count(Class<? extends T> clazz) {

        Session session = getSession();

        Criteria criteria = null;

        if(clazz == null) {

            criteria = session.createCriteria(type);

        } else {

            criteria = session.createCriteria(clazz);

        }

        criteria.setProjection(Projections.projectionList().add(Projections.rowCount()));

        //since hibernate 4 (or so) uniqueResult returns Long, not Integer, therefore needs

        //to be casted. Think about returning long rather then int!

        return ((Number) criteria.uniqueResult()).intValue();

    }

    @Override

    public List<T> list(Integer limit, Integer start) {

        return list(limit, start, null);

    }

    @Override

    public List<Object[]> group(Class<? extends T> clazz,Integer limit, Integer start, List<Grouping> groups, List<String> propertyPaths) {

        Criteria criteria = null;

        if(clazz == null){

            criteria = getSession().createCriteria(type);

        } else {

            criteria = getSession().createCriteria(clazz);

        }

        addGroups(criteria,groups);

        if(limit != null) {

            criteria.setFirstResult(start);

            criteria.setMaxResults(limit);

        }

        List<Object[]> result = criteria.list();

        if(propertyPaths != null && !propertyPaths.isEmpty()) {

          for(Object[] objects : result) {

            defaultBeanInitializer.initialize(objects[0], propertyPaths);

          }

        }

        return result;

    }

    protected void countGroups(DetachedCriteria criteria,List<Grouping> groups) {

        if(groups != null){

            Map<String,String> aliases = new HashMap<String,String>();

            for(Grouping grouping : groups) {

                if(grouping.getAssociatedObj() != null) {

                    String alias = null;

                    if((alias = aliases.get(grouping.getAssociatedObj())) == null) {

                        alias = grouping.getAssociatedObjectAlias();

                        aliases.put(grouping.getAssociatedObj(), alias);

                        criteria.createAlias(grouping.getAssociatedObj(),alias);

                    }

                }

            }

            ProjectionList projectionList = Projections.projectionList();

            for(Grouping grouping : groups) {

                grouping.addProjection(projectionList);

            }

            criteria.setProjection(projectionList);

        }

    }

    protected void addGroups(Criteria criteria,List<Grouping> groups) {

        if(groups != null){

            Map<String,String> aliases = new HashMap<String,String>();

            for(Grouping grouping : groups) {

                if(grouping.getAssociatedObj() != null) {

                    String alias = null;

                    if((alias = aliases.get(grouping.getAssociatedObj())) == null) {

                        alias = grouping.getAssociatedObjectAlias();

                        aliases.put(grouping.getAssociatedObj(), alias);

                        criteria.createAlias(grouping.getAssociatedObj(),alias);

                    }

                }

            }

            ProjectionList projectionList = Projections.projectionList();

            for(Grouping grouping : groups) {

                grouping.addProjection(projectionList);

            }

            criteria.setProjection(projectionList);

            for(Grouping grouping : groups) {

                grouping.addOrder(criteria);

            }

        }

    }

    protected void addCriteria(Criteria criteria, List<Criterion> criterion) {

        if(criterion != null) {

            for(Criterion c : criterion) {

                criteria.add(c);

            }

        }

    }

    protected void addOrder(FullTextQuery fullTextQuery, List<OrderHint> orderHints) {

        //FIXME preliminary hardcoded type:

    	int type = SortField.STRING;

    	if(orderHints != null && !orderHints.isEmpty()) {

            org.apache.lucene.search.Sort sort = new Sort();

            SortField[] sortFields = new SortField[orderHints.size()];

            for(int i = 0; i < orderHints.size(); i++) {

                OrderHint orderHint = orderHints.get(i);

                switch(orderHint.getSortOrder()) {

                case ASCENDING:

                    sortFields[i] = new SortField(orderHint.getPropertyName(), type, true);

                    break;

                case DESCENDING:

                default:

                    sortFields[i] = new SortField(orderHint.getPropertyName(), type, false);

                }

            }

            sort.setSort(sortFields);

            fullTextQuery.setSort(sort);

        }

    }

    @Override

    public List<T> list(Integer limit, Integer start, List<OrderHint> orderHints) {

        return list(limit,start,orderHints,null);

    }

    @Override

    public List<T> list(Integer limit, Integer start, List<OrderHint> orderHints, List<String> propertyPaths) {

        Criteria criteria = getSession().createCriteria(type);

        if(limit != null) {

            criteria.setFirstResult(start);

            criteria.setMaxResults(limit);

        }

        addOrder(criteria,orderHints);

        List<T> results = criteria.list();

        defaultBeanInitializer.initializeAll(results, propertyPaths);

        return results;

    }

    @Override

    public <S extends T> List<S> list(Class<S> clazz, Integer limit, Integer start, List<OrderHint> orderHints, List<String> propertyPaths) {

        Criteria criteria = null;

        if(clazz == null) {

            criteria = getSession().createCriteria(type);

        } else {

            criteria = getSession().createCriteria(clazz);

        }

        if(limit != null) {

            if(start != null) {

                criteria.setFirstResult(start);

            } else {

                criteria.setFirstResult(0);

            }

            criteria.setMaxResults(limit);

        }

        addOrder(criteria,orderHints);

        List<S> results = criteria.list();

        defaultBeanInitializer.initializeAll(results, propertyPaths);

        return results;

    }

    public <S extends T> List<S> list(Class<S> type, Integer limit, Integer start, List<OrderHint> orderHints) {

        return list(type,limit,start,orderHints,null);

    }

    @Override

    public <S extends T> List<S> list(Class<S> type, Integer limit, Integer start) {

        return list(type,limit,start,null,null);

    }

    @Override

    public List<T> rows(String tableName, int limit, int start) {

        Query query = getSession().createQuery("from " + tableName + " order by uuid");

        query.setFirstResult(start);

        query.setMaxResults(limit);

        List<T> result = query.list();

        return result;

    }

    @Override

    public Class<T> getType() {

        return type;

    }

    protected void setPagingParameter(Query query, Integer pageSize, Integer pageNumber){

        if(pageSize != null) {

            query.setMaxResults(pageSize);

            if(pageNumber != null) {

                query.setFirstResult(pageNumber * pageSize);

            } else {

                query.setFirstResult(0);

            }

        }

    }

    protected void setPagingParameter(AuditQuery query, Integer pageSize, Integer pageNumber){

        if(pageSize != null) {

            query.setMaxResults(pageSize);

            if(pageNumber != null) {

                query.setFirstResult(pageNumber * pageSize);

            } else {

                query.setFirstResult(0);

            }

        }

    }

    @Override

    public int count(T example, Set<String> includeProperties) {

        Criteria criteria = getSession().createCriteria(example.getClass());

        addExample(criteria,example,includeProperties);

        criteria.setProjection(Projections.rowCount());

        return ((Number)criteria.uniqueResult()).intValue();

    }

    protected void addExample(Criteria criteria, T example, Set<String> includeProperties) {

        if(includeProperties != null && !includeProperties.isEmpty()) {

            criteria.add(Example.create(example).setPropertySelector(new PropertySelectorImpl(includeProperties)));

            ClassMetadata classMetadata = getSession().getSessionFactory().getClassMetadata(example.getClass());

            for(String property : includeProperties) {

                Type type  = classMetadata.getPropertyType(property);

                if(type.isEntityType()) {

                    try {

                        Field field = ReflectionUtils.findField(example.getClass(), property);

                        field.setAccessible(true);

                        Object value =  field.get(example);

                        if(value != null) {

                            criteria.add(Restrictions.eq(property,value));

                        } else {

                            criteria.add(Restrictions.isNull(property));

                        }

                    } catch (SecurityException se) {

                        throw new InvalidDataAccessApiUsageException("Tried to add criteria for property " + property, se);

                    } catch (HibernateException he) {

                        throw new InvalidDataAccessApiUsageException("Tried to add criteria for property " + property, he);

                    } catch (IllegalArgumentException iae) {

                        throw new InvalidDataAccessApiUsageException("Tried to add criteria for property " + property, iae);

                    } catch (IllegalAccessException ie) {