EDIT

// $Id$

/**

* 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.api.service;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.HashMap;

import java.util.HashSet;

import java.util.List;

import java.util.Map;

import java.util.Set;

import org.apache.log4j.Logger;

import org.hibernate.criterion.Criterion;

import org.springframework.transaction.annotation.Transactional;

import eu.etaxonomy.cdm.api.service.config.IIdentifiableEntityServiceConfigurator;

import eu.etaxonomy.cdm.api.service.pager.Pager;

import eu.etaxonomy.cdm.api.service.pager.impl.DefaultPagerImpl;

import eu.etaxonomy.cdm.common.monitor.DefaultProgressMonitor;

import eu.etaxonomy.cdm.common.monitor.IProgressMonitor;

import eu.etaxonomy.cdm.hibernate.HibernateProxyHelper;

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

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

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

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

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

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

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

import eu.etaxonomy.cdm.model.media.Rights;

import eu.etaxonomy.cdm.model.name.NonViralName;

import eu.etaxonomy.cdm.model.reference.Reference;

import eu.etaxonomy.cdm.model.reference.ReferenceFactory;

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

import eu.etaxonomy.cdm.persistence.dao.hibernate.HibernateBeanInitializer;

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

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

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

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

import eu.etaxonomy.cdm.strategy.cache.common.IIdentifiableEntityCacheStrategy;

import eu.etaxonomy.cdm.strategy.match.DefaultMatchStrategy;

import eu.etaxonomy.cdm.strategy.match.IMatchStrategy;

import eu.etaxonomy.cdm.strategy.match.IMatchable;

import eu.etaxonomy.cdm.strategy.match.MatchException;

import eu.etaxonomy.cdm.strategy.merge.IMergable;

import eu.etaxonomy.cdm.strategy.merge.IMergeStrategy;

import eu.etaxonomy.cdm.strategy.merge.MergeException;

public abstract class IdentifiableServiceBase<T extends IdentifiableEntity,DAO extends IIdentifiableDao<T>> extends AnnotatableServiceBase<T,DAO> 

						implements IIdentifiableEntityService<T>{

	protected static final int UPDATE_TITLE_CACHE_DEFAULT_STEP_SIZE = 1000;

	protected static final  Logger logger = Logger.getLogger(IdentifiableServiceBase.class);

	@Override

	@Transactional(readOnly = true)

	public Pager<Rights> getRights(T t, Integer pageSize, Integer pageNumber, List<String> propertyPaths) {

        Integer numberOfResults = dao.countRights(t);

		List<Rights> results = new ArrayList<Rights>();

		if(numberOfResults > 0) { // no point checking again //TODO use AbstractPagerImpl.hasResultsInRange(numberOfResults, pageNumber, pageSize)

			results = dao.getRights(t, pageSize, pageNumber,propertyPaths); 

		}

		return new DefaultPagerImpl<Rights>(pageNumber, numberOfResults, pageSize, results);

	}

	@Override

	@Transactional(readOnly = true)

	public Pager<IdentifiableSource> getSources(T t, Integer pageSize, Integer pageNumber, List<String> propertyPaths) {

		 Integer numberOfResults = dao.countSources(t);

			List<IdentifiableSource> results = new ArrayList<IdentifiableSource>();

			if(numberOfResults > 0) { // no point checking again //TODO use AbstractPagerImpl.hasResultsInRange(numberOfResults, pageNumber, pageSize)

				results = dao.getSources(t, pageSize, pageNumber,propertyPaths); 

			}

			return new DefaultPagerImpl<IdentifiableSource>(pageNumber, numberOfResults, pageSize, results);

	}

	@Transactional(readOnly = false)

	@Override

	public T replace(T x, T y) {

		return dao.replace(x, y);

	}

	/**

	 * FIXME Candidate for harmonization

	 * Given that this method is strongly typed, and generic, could we not simply expose it as

	 * List<T> findByTitle(String title) as it is somewhat less cumbersome. Admittedly, I don't 

	 * understand what is going on with the configurators etc. so maybe there is a good reason for

	 * the design of this method. 

	 * @param title

	 * @return

	 */

	@Transactional(readOnly = true)

	protected List<T> findCdmObjectsByTitle(String title){

		return ((IIdentifiableDao)dao).findByTitle(title);

	}

	@Transactional(readOnly = true)

	protected List<T> findCdmObjectsByTitle(String title, Class<T> clazz){

		return ((IIdentifiableDao)dao).findByTitleAndClass(title, clazz);

	}

	@Transactional(readOnly = true)

	protected List<T> findCdmObjectsByTitle(String title, CdmBase sessionObject){

		return ((IIdentifiableDao)dao).findByTitle(title, sessionObject);

	}

	/*

	 * TODO - Migrated from CommonServiceBase

	 *  (non-Javadoc)

	 * @see eu.etaxonomy.cdm.api.service.ICommonService#getSourcedObjectById(java.lang.String, java.lang.String)

	 */

	@Transactional(readOnly = true)

	@Override

	public ISourceable getSourcedObjectByIdInSource(Class clazz, String idInSource, String idNamespace) {

		ISourceable result = null;

		List<T> list = dao.findOriginalSourceByIdInSource(idInSource, idNamespace);

		if (! list.isEmpty()){

			result = list.get(0);

		}

		return result;

	}

	@Transactional(readOnly = true)

	@Override

	public List<UuidAndTitleCache<T>> getUuidAndTitleCache() {

		return dao.getUuidAndTitleCache();

	}

	@Transactional(readOnly = true)

	@Override

	public Pager<T> findByTitle(Class<? extends T> clazz, String queryString,MatchMode matchmode, List<Criterion> criteria, Integer pageSize, Integer pageNumber, List<OrderHint> orderHints, List<String> propertyPaths) {

		 Integer numberOfResults = dao.countByTitle(clazz, queryString, matchmode, criteria);

		 List<T> results = new ArrayList<T>();

		 if(numberOfResults > 0) { // no point checking again //TODO use AbstractPagerImpl.hasResultsInRange(numberOfResults, pageNumber, pageSize)

				results = dao.findByTitle(clazz, queryString, matchmode, criteria, pageSize, pageNumber, orderHints, propertyPaths); 

		 }

		  return new DefaultPagerImpl<T>(pageNumber, numberOfResults, pageSize, results);

	}

	@Transactional(readOnly = true)

	@Override

	public Pager<T> findByTitle(IIdentifiableEntityServiceConfigurator<T> config){

		return findByTitle(config.getClazz(), config.getTitleSearchStringSqlized(), config.getMatchMode(), config.getCriteria(), config.getPageSize(), config.getPageNumber(), config.getOrderHints(), config.getPropertyPaths());

	}

	@Transactional(readOnly = true)

	@Override

	public List<T> listByTitle(Class<? extends T> clazz, String queryString,MatchMode matchmode, List<Criterion> criteria, Integer pageSize, Integer pageNumber, List<OrderHint> orderHints, List<String> propertyPaths) {

		 Integer numberOfResults = dao.countByTitle(clazz, queryString, matchmode, criteria);

		 List<T> results = new ArrayList<T>();

		 if(numberOfResults > 0) { // no point checking again //TODO use AbstractPagerImpl.hasResultsInRange(numberOfResults, pageNumber, pageSize)

				results = dao.findByTitle(clazz, queryString, matchmode, criteria, pageSize, pageNumber, orderHints, propertyPaths); 

		 }

		 return results;

	}

	@Transactional(readOnly = true)

	@Override

	public Pager<T> findTitleCache(Class<? extends T> clazz, String queryString, Integer pageSize, Integer pageNumber, List<OrderHint> orderHints, MatchMode matchMode){

		long numberOfResults = dao.countTitleCache(clazz, queryString, matchMode);

		 List<T> results = new ArrayList<T>();

		 if(numberOfResults > 0) { // no point checking again //TODO use AbstractPagerImpl.hasResultsInRange(numberOfResults, pageNumber, pageSize)

				results = dao.findTitleCache(clazz, queryString, pageSize, pageNumber, orderHints, matchMode);

		 }

		 int r = 0;

		 r += numberOfResults;

		  return new DefaultPagerImpl<T>(pageNumber, r , pageSize, results);

	}

	@Transactional(readOnly = true)

	@Override

	public List<T> listByReferenceTitle(Class<? extends T> clazz, String queryString,MatchMode matchmode, List<Criterion> criteria, Integer pageSize, Integer pageNumber, List<OrderHint> orderHints, List<String> propertyPaths) {

		 Integer numberOfResults = dao.countByReferenceTitle(clazz, queryString, matchmode, criteria);

		 List<T> results = new ArrayList<T>();

		 if(numberOfResults > 0) { // no point checking again //TODO use AbstractPagerImpl.hasResultsInRange(numberOfResults, pageNumber, pageSize)

				results = dao.findByReferenceTitle(clazz, queryString, matchmode, criteria, pageSize, pageNumber, orderHints, propertyPaths); 

		 }

		 return results;

	}

	@Transactional(readOnly = true)

	@Override

	public T find(LSID lsid) {

		return dao.find(lsid);

	}

	@Transactional(readOnly = true)

	@Override

	public Pager<T> search(Class<? extends T> clazz, String queryString, Integer pageSize, Integer pageNumber, List<OrderHint> orderHints, List<String> propertyPaths) {

        Integer numberOfResults = dao.count(clazz,queryString);

		List<T> results = new ArrayList<T>();

		if(numberOfResults > 0) { // no point checking again //TODO use AbstractPagerImpl.hasResultsInRange(numberOfResults, pageNumber, pageSize)

			results = dao.search(clazz,queryString, pageSize, pageNumber, orderHints, propertyPaths); 

		}

		return new DefaultPagerImpl<T>(pageNumber, numberOfResults, pageSize, results);

	}

	@Override

	@Transactional(readOnly = false)

	public void updateTitleCache() {

		updateTitleCache(null, null, null, null);

	}

	@Transactional(readOnly = false)  //TODO check transactional behaviour, e.g. what happens with the session if count is very large 

	protected <S extends T > void updateTitleCacheImpl(Class<S> clazz, Integer stepSize, IIdentifiableEntityCacheStrategy<T> cacheStrategy, IProgressMonitor monitor) {

		if (stepSize == null){

			stepSize = UPDATE_TITLE_CACHE_DEFAULT_STEP_SIZE;

		}

		if (monitor == null){

			monitor = DefaultProgressMonitor.NewInstance();

		}

		int count = dao.count(clazz);

		monitor.beginTask("update titles", count);

		int worked = 0;

		for(int i = 0 ; i < count ; i = i + stepSize){

			// not sure if such strict ordering is necessary here, but for safety reasons I do it

			ArrayList<OrderHint> orderHints = new ArrayList<OrderHint>();

			orderHints.add( new OrderHint("id", OrderHint.SortOrder.ASCENDING));

			Map<Class<? extends CdmBase>, AutoPropertyInitializer<CdmBase>> oldAutoInit = switchOfAutoinitializer();

			List<S> list = this.list(clazz, stepSize, i, orderHints, null);

			switchOnOldAutoInitializer(oldAutoInit);

			List<T> entitiesToUpdate = new ArrayList<T>();

			for (T entity : list){

				HibernateProxyHelper.deproxy(entity, clazz);

				if (entity.isProtectedTitleCache() == false){

					updateTitleCacheForSingleEntity(cacheStrategy, entitiesToUpdate, entity);

				}

				worked++;

			}

			for (T entity: entitiesToUpdate){

				if (entity.getTitleCache() != null){

					//System.err.println(entity.getTitleCache());

				}else{

					//System.err.println("no titleCache" + ((NonViralName)entity).getNameCache());

				}

			}

			saveOrUpdate(entitiesToUpdate);

			monitor.worked(list.size());

			if (monitor.isCanceled()){

				monitor.done();

				return;

			}

		}

		monitor.done();

	}

	/**

	 * Brings back all auto initializers to the bean initializer

	 * @see #switchOfAutoinitializer()

	 * @param oldAutoInit

	 */

	protected void switchOnOldAutoInitializer(

			Map<Class<? extends CdmBase>, AutoPropertyInitializer<CdmBase>> oldAutoInit) {

		HibernateBeanInitializer initializer = (HibernateBeanInitializer)this.appContext.getBean("defaultBeanInitializer");

		initializer.setBeanAutoInitializers(oldAutoInit);

	}

	/**

	 * Removes all auto initializers from the bean initializer

	 * 

	 * @see #switchOnOldAutoInitializer(Map)

	 * @return 

	 */

	protected Map<Class<? extends CdmBase>, AutoPropertyInitializer<CdmBase>> switchOfAutoinitializer() {

		HibernateBeanInitializer initializer = (HibernateBeanInitializer)this.appContext.getBean("defaultBeanInitializer");

		Map<Class<? extends CdmBase>, AutoPropertyInitializer<CdmBase>> oldAutoInitializers = initializer.getBeanAutoInitializers();

		Map<Class<? extends CdmBase>, AutoPropertyInitializer<CdmBase>> map = new HashMap<Class<? extends CdmBase>, AutoPropertyInitializer<CdmBase>>();

		initializer.setBeanAutoInitializers(map);

		return oldAutoInitializers;

	}

	/**

	 * @param cacheStrategy

	 * @param entitiesToUpdate

	 * @param entity

	 */

	/**

	 * @param cacheStrategy

	 * @param entitiesToUpdate

	 * @param entity

	 */

	private void updateTitleCacheForSingleEntity(

			IIdentifiableEntityCacheStrategy<T> cacheStrategy,

			List<T> entitiesToUpdate, T entity) {

		assert (entity.isProtectedTitleCache() == false );

		//exclude recursive inreferences

		if (entity.isInstanceOf(Reference.class)){

			Reference<?> ref = CdmBase.deproxy(entity, Reference.class);

			if (ref.getInReference() != null && ref.getInReference().equals(ref)){

				return;

			}

		}

		//define the correct cache strategy

		IIdentifiableEntityCacheStrategy entityCacheStrategy = cacheStrategy;

		if (entityCacheStrategy == null){

			entityCacheStrategy = entity.getCacheStrategy();

			//FIXME find out why the wrong cache strategy is loaded here, see #1876 

			if (entity instanceof Reference){

				entityCacheStrategy = ReferenceFactory.newReference(((Reference<?>)entity).getType()).getCacheStrategy();

			}

		}

		entity.setCacheStrategy(entityCacheStrategy);

		//old titleCache

		entity.setProtectedTitleCache(true);

		String oldTitleCache = entity.getTitleCache();

		entity.setTitleCache(oldTitleCache, false);   //before we had entity.setProtectedTitleCache(false) but this deleted the titleCache itself

		//NonViralNames and Reference have more caches //TODO handle in NameService

		String oldNameCache = null;

		String oldFullTitleCache = null;

		String oldAbbrevTitleCache = null;

		if (entity instanceof NonViralName ){

			try{

				NonViralName<?> nvn = (NonViralName) entity;

				if (!nvn.isProtectedNameCache()){

					nvn.setProtectedNameCache(true);

					oldNameCache = nvn.getNameCache();

					nvn.setProtectedNameCache(false);

				}

				if (!nvn.isProtectedFullTitleCache()){

					nvn.setProtectedFullTitleCache(true);

					oldFullTitleCache = nvn.getFullTitleCache();

					nvn.setProtectedFullTitleCache(false);

				}

			}catch(ClassCastException e){

				System.out.println("entity: " + entity.getTitleCache());

			}

		}else if (entity instanceof Reference){

			Reference<?> ref = (Reference<?>) entity;

			if (!ref.isProtectedAbbrevTitleCache()){

				ref.setProtectedAbbrevTitleCache(true);

				oldAbbrevTitleCache = ref.getAbbrevTitleCache();

				ref.setProtectedAbbrevTitleCache(false);

			}

		}

		setOtherCachesNull(entity);

		String newTitleCache= null;

		NonViralName<?> nvn = null;//TODO find better solution

		try{

			if (entity instanceof NonViralName){

				nvn = (NonViralName) entity;

				newTitleCache = entityCacheStrategy.getTitleCache(nvn);

			} else{

				 newTitleCache = entityCacheStrategy.getTitleCache(entity);

			}

		}catch (ClassCastException e){

			nvn = HibernateProxyHelper.deproxy(entity, NonViralName.class);

			newTitleCache = entityCacheStrategy.getTitleCache(nvn);

			//System.out.println("titleCache: " +entity.getTitleCache());

		}

		if ( oldTitleCache == null   || oldTitleCache != null && ! oldTitleCache.equals(newTitleCache) ){

			entity.setTitleCache(null, false);

			String newCache = entity.getTitleCache();

			if (newCache == null){

				logger.warn("newCache should never be null");

			}

			if (oldTitleCache == null){

				logger.info("oldTitleCache should never be null");

			}

			if (nvn != null){

				//NonViralName<?> nvn = (NonViralName) entity;

				nvn.getNameCache();

				nvn.getFullTitleCache();

			}

			if (entity instanceof Reference){

				Reference<?> ref = (Reference<?>) entity;

				ref.getAbbrevTitleCache();

			}

			entitiesToUpdate.add(entity);

		}else if (nvn != null){

			//NonViralName<?> nvn = (NonViralName) entity;

			String newNameCache = nvn.getNameCache();

			String newFullTitleCache = nvn.getFullTitleCache();

			if ((oldNameCache == null && !nvn.isProtectedNameCache()) || (oldNameCache != null && !oldNameCache.equals(newNameCache))){

				entitiesToUpdate.add(entity);

			}else if ((oldFullTitleCache == null && !nvn.isProtectedFullTitleCache()) || (oldFullTitleCache != null && !oldFullTitleCache.equals(newFullTitleCache))){

				entitiesToUpdate.add(entity);

			}

		}else if (entity instanceof Reference){

			Reference<?> ref = (Reference<?>) entity;

			String newAbbrevTitleCache = ref.getAbbrevTitleCache();

			if ( (oldAbbrevTitleCache == null && !ref.isProtectedAbbrevTitleCache() ) || (oldAbbrevTitleCache != null && !oldAbbrevTitleCache.equals(newAbbrevTitleCache))){

				entitiesToUpdate.add(entity);

			}

		}

	}

	/**

	 * Needs override if not only the title cache should be set to null to

	 * generate the correct new title cache

	 */

	protected void setOtherCachesNull(T entity) {

		return;

	}

	private class DeduplicateState{

		String lastTitleCache;

		Integer pageSize = 50;

		int nPages = 3;

		int startPage = 0;

		boolean isCompleted = false;

		int result; 

	}

	@Override

	@Transactional(readOnly = false)

	public int deduplicate(Class<? extends T> clazz, IMatchStrategy matchStrategy, IMergeStrategy mergeStrategy) {

		DeduplicateState dedupState = new DeduplicateState();

		if (clazz == null){

			logger.warn("Deduplication clazz must not be null!");

			return 0;

		}

		if (! ( IMatchable.class.isAssignableFrom(clazz) && IMergable.class.isAssignableFrom(clazz) )  ){

			logger.warn("Deduplication implemented only for classes implementing IMatchable and IMergeable. No deduplication performed!");

			return 0;

		}

		Class matchableClass = clazz;

		if (matchStrategy == null){

			matchStrategy = DefaultMatchStrategy.NewInstance(matchableClass);

		}

		List<T> nextGroup = new ArrayList<T>();

		int result = 0;

//		double countTotal = count(clazz);

//		

//		Number countPagesN = Math.ceil(countTotal/dedupState.pageSize.doubleValue()) ; 

//		int countPages = countPagesN.intValue();

//		

		List<OrderHint> orderHints = Arrays.asList(new OrderHint[]{new OrderHint("titleCache", SortOrder.ASCENDING)});

		while (! dedupState.isCompleted){

			//get x page sizes

			List<T> objectList = getPages(clazz, dedupState, orderHints);

			//after each page check if any changes took place

			int nUnEqualPages = handleAllPages(objectList, dedupState, nextGroup, matchStrategy, mergeStrategy);

			nUnEqualPages = nUnEqualPages + dedupState.pageSize * dedupState.startPage;

			//refresh start page counter

			int finishedPages = nUnEqualPages / dedupState.pageSize;

			dedupState.startPage = finishedPages;

		}

		result += handleLastGroup(nextGroup, matchStrategy, mergeStrategy);

		return result;

	}

	private int handleAllPages(List<T> objectList, DeduplicateState dedupState, List<T> nextGroup, IMatchStrategy matchStrategy, IMergeStrategy mergeStrategy) {

		int nUnEqual = 0;

		for (T object : objectList){

			String currentTitleCache = object.getTitleCache();

			if (currentTitleCache != null && currentTitleCache.equals(dedupState.lastTitleCache)){

				//=titleCache

				nextGroup.add(object);

			}else{

				//<> titleCache

				dedupState.result += handleLastGroup(nextGroup, matchStrategy, mergeStrategy);

				nextGroup = new ArrayList<T>();

				nextGroup.add(object);

				nUnEqual++;	

			}

			dedupState.lastTitleCache = currentTitleCache;

		}

		handleLastGroup(nextGroup, matchStrategy, mergeStrategy);

		return nUnEqual;

	}

	private List<T> getPages(Class<? extends T> clazz, DeduplicateState dedupState, List<OrderHint> orderHints) {

		List<T> result = new ArrayList<T>();

		for (int pageNo = dedupState.startPage; pageNo < dedupState.startPage + dedupState.nPages; pageNo++){

			List<T> objectList = listByTitle(clazz, null, null, null, dedupState.pageSize, pageNo, orderHints, null);

			result.addAll(objectList);

		}

		if (result.size()< dedupState.nPages * dedupState.pageSize ){

			dedupState.isCompleted = true;

		}

		return result;

	}

	private int handleLastGroup(List<T> group, IMatchStrategy matchStrategy, IMergeStrategy mergeStrategy) {

		int result = 0;

		int size = group.size();

		Set<Integer> exclude = new HashSet<Integer>();  //set to collect all objects, that have been merged already

		for (int i = 0; i < size - 1; i++){

			if (exclude.contains(i)){

				continue;

			}

			for (int j = i + 1; j < size; j++){

				if (exclude.contains(j)){

					continue;

				}

				T firstObject = group.get(i);

				T secondObject = group.get(j);

				try {

					if (matchStrategy.invoke((IMatchable)firstObject, (IMatchable)secondObject)){

						commonService.merge((IMergable)firstObject, (IMergable)secondObject, mergeStrategy);

						exclude.add(j);

						result++;

					}

				} catch (MatchException e) {

					logger.warn("MatchException when trying to match " + firstObject.getTitleCache());

					e.printStackTrace();

				} catch (MergeException e) {

					logger.warn("MergeException when trying to merge " + firstObject.getTitleCache());

					e.printStackTrace();

				}

			}

		}

		return result;

	}	

	@Transactional(readOnly = true)

	@Override

	public Integer countByTitle(Class<? extends T> clazz, String queryString,MatchMode matchmode, List<Criterion> criteria){

		 Integer numberOfResults = dao.countByTitle(clazz, queryString, matchmode, criteria);

		 return numberOfResults;

	}

	@Transactional(readOnly = true)

	@Override

	public Integer countByTitle(IIdentifiableEntityServiceConfigurator<T> config){

		return countByTitle(config.getClazz(), config.getTitleSearchStringSqlized(),

				config.getMatchMode(), config.getCriteria());

	}

	@Override

	public <S extends IdentifiableEntity> List<S> listByIdentifier(

			S clazz, String identifier, DefinedTerm identifierType,

			MatchMode matchmode, Integer pageSize,

			Integer pageNumber, List<OrderHint> orderHints,

			List<String> propertyPaths) {

		return dao.findByIdentifier(clazz, identifier, identifierType,

				matchmode, pageSize, pageNumber, orderHints,

				propertyPaths);

	}

}