/**
    * 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.kew.engine.node.dao.impl;
  
  import java.util.ArrayList;
  import java.util.Iterator;
  import java.util.List;
  
  import javax.persistence.EntityManager;
  import javax.persistence.PersistenceContext;
  import javax.persistence.Query;
  
  import org.kuali.rice.core.framework.persistence.jpa.OrmUtils;
  import org.kuali.rice.kew.api.KEWPropertyConstants;
  import org.kuali.rice.kew.engine.node.Branch;
  import org.kuali.rice.kew.engine.node.NodeState;
  import org.kuali.rice.kew.engine.node.RouteNode;
  import org.kuali.rice.kew.engine.node.RouteNodeInstance;
  import org.kuali.rice.kew.engine.node.dao.RouteNodeDAO;
  
  public class RouteNodeDAOJpaImpl implements RouteNodeDAO {
  
  	@PersistenceContext(unitName="kew-unit")
  	EntityManager entityManager;
  	
      /**
  	 * @return the entityManager
  	 */
  	public EntityManager getEntityManager() {
  		return this.entityManager;
  	}
  
  	/**
  	 * @param entityManager the entityManager to set
  	 */
  	public void setEntityManager(EntityManager entityManager) {
  		this.entityManager = entityManager;
  	}
  
  	public void save(RouteNode node) {
      	if (node.getRouteNodeId() == null){
      		entityManager.persist(node);
      	} else {
      		OrmUtils.merge(entityManager, node);
      	}
      }
  
      public void save(RouteNodeInstance nodeInstance) {
      	if (nodeInstance.getRouteNodeInstanceId() == null){
      		entityManager.persist(nodeInstance);
      	} else {
      		OrmUtils.merge(entityManager, nodeInstance);
      	}
      }
  
      public void save(NodeState nodeState) {
      	if (nodeState.getNodeStateId() == null){
      		entityManager.persist(nodeState);
      	} else {
      		OrmUtils.merge(entityManager, nodeState);
      	}
      }
  
      public void save(Branch branch) {   	
      	if (branch.getBranchId() == null){
      		entityManager.persist(branch);
      	} else {
      		OrmUtils.merge(entityManager, branch);
      	}
      }
  
      public RouteNode findRouteNodeById(String nodeId) {
      	Query query = entityManager.createNamedQuery("RouteNode.FindByRouteNodeId");
      	query.setParameter(KEWPropertyConstants.ROUTE_NODE_ID, nodeId);
      	return (RouteNode) query.getSingleResult();
      }
  
      public RouteNodeInstance findRouteNodeInstanceById(String nodeInstanceId) {
      	Query query = entityManager.createNamedQuery("RouteNodeInstance.FindByRouteNodeInstanceId");
      	query.setParameter(KEWPropertyConstants.ROUTE_NODE_INSTANCE_ID, nodeInstanceId);
  
     	 	return (RouteNodeInstance) query.getSingleResult(); 		
      }
  
      @SuppressWarnings("unchecked")
      public List<RouteNodeInstance> getActiveNodeInstances(String documentId) {
     	Query query = entityManager.createNamedQuery("RouteNodeInstance.FindActiveNodeInstances");
     	query.setParameter(KEWPropertyConstants.DOCUMENT_ID, documentId);
     	return (List<RouteNodeInstance>)query.getResultList();
     }
 
     @SuppressWarnings("unchecked")
     public List<RouteNodeInstance> getTerminalNodeInstances(String documentId) {
     	Query query = entityManager.createNamedQuery("RouteNodeInstance.FindTerminalNodeInstances");
     	query.setParameter(KEWPropertyConstants.DOCUMENT_ID, documentId);
 		
 		//FIXME: Can we do this better using just the JPQL query?  
 		List<RouteNodeInstance> terminalNodes = new ArrayList<RouteNodeInstance>();
 		List<RouteNodeInstance> routeNodeInstances = (List<RouteNodeInstance>) query.getResultList();
 		for (RouteNodeInstance routeNodeInstance : routeNodeInstances) {
 		    if (routeNodeInstance.getNextNodeInstances().isEmpty()) {
 		    	terminalNodes.add(routeNodeInstance);
 		    }
 		}
 		return terminalNodes;
     }
 
     public List getInitialNodeInstances(String documentId) {
     	//FIXME: Not sure this query is returning what it needs to     	                                              
     	Query query = entityManager.createNamedQuery("RouteNodeInstance.FindInitialNodeInstances");
     	query.setParameter(KEWPropertyConstants.DOCUMENT_ID, documentId);
 		return (List)query.getResultList();
     }
 
     public NodeState findNodeState(Long nodeInstanceId, String key) {
     	Query query = entityManager.createNamedQuery("NodeState.FindNodeState");
     	query.setParameter(KEWPropertyConstants.NODE_INSTANCE_ID, nodeInstanceId);
     	query.setParameter(KEWPropertyConstants.KEY, key);
 		return (NodeState) query.getSingleResult();
     }
 
     public RouteNode findRouteNodeByName(String documentTypeId, String name) {
     	Query query = entityManager.createNamedQuery("RouteNode.FindRouteNodeByName");
     	query.setParameter(KEWPropertyConstants.DOCUMENT_TYPE_ID, documentTypeId);
     	query.setParameter(KEWPropertyConstants.ROUTE_NODE_NAME, name);
 		return (RouteNode)query.getSingleResult();    	
     }
 
     public List<RouteNode> findFinalApprovalRouteNodes(String documentTypeId) {
     	Query query = entityManager.createNamedQuery("RouteNode.FindApprovalRouteNodes");
     	query.setParameter(KEWPropertyConstants.DOCUMENT_TYPE_ID, documentTypeId);
     	query.setParameter(KEWPropertyConstants.FINAL_APPROVAL, Boolean.TRUE);
     	return new ArrayList<RouteNode>(query.getResultList());
     }
 
     public List findProcessNodeInstances(RouteNodeInstance process) {
     	Query query = entityManager.createNamedQuery("RouteNodeInstance.FindProcessNodeInstances");
     	query.setParameter(KEWPropertyConstants.PROCESS_ID, process.getRouteNodeInstanceId());
     	return (List) query.getResultList();
     }
 
     public List findRouteNodeInstances(String documentId) {
     	Query query = entityManager.createNamedQuery("RouteNodeInstance.FindRouteNodeInstances");
     	query.setParameter(KEWPropertyConstants.DOCUMENT_ID, documentId);
     	return (List) query.getResultList();
     }
 
     public void deleteLinksToPreNodeInstances(RouteNodeInstance routeNodeInstance) {
 		List<RouteNodeInstance> preNodeInstances = routeNodeInstance.getPreviousNodeInstances();
 		for (Iterator<RouteNodeInstance> preNodeInstanceIter = preNodeInstances.iterator(); preNodeInstanceIter.hasNext();) {
 		    RouteNodeInstance preNodeInstance = (RouteNodeInstance) preNodeInstanceIter.next();
 		    List<RouteNodeInstance> nextInstances = preNodeInstance.getNextNodeInstances();
 		    nextInstances.remove(routeNodeInstance);
 		    entityManager.merge(preNodeInstance);
 		}
     }
 
     public void deleteRouteNodeInstancesHereAfter(RouteNodeInstance routeNodeInstance) {
     	RouteNodeInstance rnInstance = findRouteNodeInstanceById(routeNodeInstance.getRouteNodeInstanceId());
     	entityManager.remove(rnInstance);
     }
 
     public void deleteNodeStateById(Long nodeStateId) {
     	Query query = entityManager.createNamedQuery("RouteNode.FindNodeStateById");
     	query.setParameter(KEWPropertyConstants.ROUTE_NODE_STATE_ID, nodeStateId);
     	NodeState nodeState = (NodeState) query.getSingleResult();
     	entityManager.remove(nodeState);
     }
 
     public void deleteNodeStates(List statesToBeDeleted) {
 		for (Iterator stateToBeDeletedIter = statesToBeDeleted.iterator(); stateToBeDeletedIter.hasNext();) {
 		    Long stateId = (Long) stateToBeDeletedIter.next();
 		    deleteNodeStateById(stateId);
 		}
     }
 
 }