/**
 * Copyright 1996-2014 FoxBPM ORG.
 *
 * Licensed under the Apache 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.apache.org/licenses/LICENSE-2.0
 * 
 * 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.
 * 
 * @author kenshin
 * @author ych
 */
package org.foxbpm.engine.impl.persistence;

import java.util.List;

import org.foxbpm.engine.db.PersistentObject;
import org.foxbpm.engine.impl.entity.ProcessInstanceEntity;
import org.foxbpm.engine.impl.runtime.ProcessInstanceQueryImpl;
import org.foxbpm.engine.runtime.ProcessInstance;
import org.foxbpm.kernel.event.KernelEvent;

/**
 * 流程实例管理器
 * 
 * @author kenshin
 * 
 */
public class ProcessInstanceManager extends AbstractManager {
	
	public ProcessInstanceEntity findProcessInstanceById(String id) {
		return selectById(ProcessInstanceEntity.class , id);
	}
	
	public long findProcessInstanceCountByQueryCriteria(
	    ProcessInstanceQueryImpl processsInstanceQuery) {
		return (Long) selectOne("selectProcessInstanceCountByQueryCriteria", processsInstanceQuery);
	}
	
	@SuppressWarnings("unchecked")
	public List<ProcessInstance> findProcessInstanceByQueryCriteria(
	    ProcessInstanceQueryImpl processInstaceQuery) {
		return (List<ProcessInstance>) selectList("selectProcessInstanceByQueryCriteria", processInstaceQuery);
	}
	
	@SuppressWarnings("unchecked")
	public void deleteProcessInstancesByProcessDefinition(String processDefinitionId,
	    boolean cascade) {
		// 删除流程实例
		deleteProcessInstanceByProcessDefinitionId(processDefinitionId);
		if (cascade) {
			List<String> processInstanceIds = (List<String>) selectList("selectProcessInstanceIdsByProcessDefinitionId", processDefinitionId);
			for (String processInstanceId : processInstanceIds) {
				cascadeDelete(processInstanceId);
			}
		}
	}
	
	private void cascadeDelete(String processInstanceId) {
		TokenManager tokenManager = getTokenManager();
		TaskManager taskManager = getTaskManager();
		VariableManager variableManager = getVariableManager();
		// 删除令牌
		tokenManager.deleteTokenByProcessInstanceId(processInstanceId);
		// 删除任务
		taskManager.deleteTaskByProcessInstanceId(processInstanceId);
		// 删除变量
		variableManager.deleteVariableByProcessInstanceId(processInstanceId);
		// 删除流程实例所关联的运行轨迹
		getRunningTrackManager().deleteRunningTrackByProcessInstanceId(processInstanceId);
		
		// 删除流程实例所关联的调度器
		getSchedulerManager().deleteJobByInstanceId(processInstanceId);
		
	}
	
	/**
	 * 根据processDefinitionId删除流程实例 只删除流程实例，不级联其他数据
	 * 
	 * @param processInstanceId
	 */
	private void deleteProcessInstanceByProcessDefinitionId(String processDefinitionId) {
		delete("deleteProcessInstanceByProcessDefinitionId", processDefinitionId);
	}
	
	/**
	 * 根据流程实例号删除流程实例
	 * 
	 * @param processInstanceId
	 */
	public void deleteProcessInstanceById(String processInstanceId) {
		delete("deleteProcessInstanceById", processInstanceId);
		cascadeDelete(processInstanceId);
	}
	
	@Override
	public void beforeFlush() {
		removeUnnecessaryOperations();
		for(PersistentObject obj : insertedObjects){
			ProcessInstanceEntity processInstanceEntity = (ProcessInstanceEntity)obj;
			processInstanceEntity.getRootToken().fireEvent(KernelEvent.BEFORE_PROCESS_SAVE);
		}
		List<PersistentObject> updateObjects = getUpdatedObjects();
		for(PersistentObject obj : updateObjects){
			ProcessInstanceEntity processInstanceEntity = (ProcessInstanceEntity)obj;
			processInstanceEntity.getRootToken().fireEvent(KernelEvent.BEFORE_PROCESS_SAVE);
		}
		
	}
	
}