/**
    * Copyright 2005-2011 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.opensource.org/licenses/ecl2.php
    *
   * 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.rice.krad.criteria;
  
  import org.apache.commons.lang.StringUtils;
  import org.kuali.rice.core.api.CoreApiServiceLocator;
  import org.kuali.rice.core.api.config.ConfigurationException;
  import org.kuali.rice.core.api.criteria.GenericQueryResults;
  import org.kuali.rice.core.api.criteria.LookupCustomizer;
  import org.kuali.rice.core.api.criteria.QueryByCriteria;
  import org.kuali.rice.core.framework.persistence.jpa.OrmUtils;
  import org.kuali.rice.krad.bo.ModuleConfiguration;
  import org.kuali.rice.krad.service.KRADServiceLocator;
  import org.kuali.rice.krad.service.KRADServiceLocatorWeb;
  import org.kuali.rice.krad.service.KualiModuleService;
  import org.kuali.rice.krad.service.ModuleService;
  
  import javax.persistence.EntityManager;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.Map;
  
  public class CriteriaLookupDaoProxy implements CriteriaLookupDao {
      CriteriaLookupDao criteriaLookupDaoOjb;
      CriteriaLookupDao criteriaLookupDaoJpa;
      private static KualiModuleService kualiModuleService;
      private static Map<String, CriteriaLookupDao> lookupDaoValues = Collections.synchronizedMap(new HashMap<String, CriteriaLookupDao>());
  
      public void setCriteriaLookupDaoJpa(CriteriaLookupDao lookupDaoJpa) {
  		this.criteriaLookupDaoJpa = lookupDaoJpa;
  	}
  
  	public void setCriteriaLookupDaoOjb(CriteriaLookupDao lookupDaoOjb) {
  		this.criteriaLookupDaoOjb = lookupDaoOjb;
  	}
  
      private CriteriaLookupDao getDao(Class clazz) {
          ModuleService moduleService = getKualiModuleService().getResponsibleModuleService(clazz);
          if (moduleService != null) {
              ModuleConfiguration moduleConfig = moduleService.getModuleConfiguration();
              String dataSourceName = "";
              EntityManager entityManager = null;
              if (moduleConfig != null) {
                  dataSourceName = moduleConfig.getDataSourceName();
                  entityManager = moduleConfig.getEntityManager();
              }
  
              if (StringUtils.isNotEmpty(dataSourceName)) {
                  if (lookupDaoValues.get(dataSourceName) != null) {
                      return lookupDaoValues.get(dataSourceName);
                  } else {
                      if (OrmUtils.isJpaAnnotated(clazz) && OrmUtils.isJpaEnabled()) {
                          //using JPA
                  	    CriteriaLookupDaoJpa classSpecificLookupDaoJpa = new CriteriaLookupDaoJpa();
                  		if (entityManager != null) {
                  			classSpecificLookupDaoJpa.setEntityManager(entityManager);
                  			lookupDaoValues.put(dataSourceName, classSpecificLookupDaoJpa);
                  			return classSpecificLookupDaoJpa;
                  		} else {
                  			throw new ConfigurationException("EntityManager is null. EntityManager must be set in the Module Configuration bean in the appropriate spring beans xml. (see nested exception for details).");
                  		}
  					} else {
  						CriteriaLookupDaoOjb classSpecificLookupDaoOjb = new CriteriaLookupDaoOjb();
                          classSpecificLookupDaoOjb.setJcdAlias(dataSourceName);
                          lookupDaoValues.put(dataSourceName, classSpecificLookupDaoOjb);
                          return classSpecificLookupDaoOjb;
                      }
                  }
  
              }
          }
          //return lookupDaoJpa;
          return (OrmUtils.isJpaAnnotated(clazz) && OrmUtils.isJpaEnabled()) ? criteriaLookupDaoJpa : criteriaLookupDaoOjb;
      }
  
      @Override
      public <T> GenericQueryResults<T> lookup(Class<T> queryClass, QueryByCriteria criteria) {
          return getDao(queryClass).lookup(queryClass, criteria);
      }
  
      @Override
      public <T> GenericQueryResults<T> lookup(Class<T> queryClass, QueryByCriteria criteria,
              LookupCustomizer<T> customizer) {
          return getDao(queryClass).lookup(queryClass, criteria, customizer);
      }
  
     private static KualiModuleService getKualiModuleService() {
         if (kualiModuleService == null) {
             kualiModuleService = KRADServiceLocatorWeb.getKualiModuleService();
         }
         return kualiModuleService;
     }
 }