package com.bjsxt.oa.managers.impl;

import java.io.ByteArrayInputStream;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

import org.jbpm.JbpmConfiguration;
import org.jbpm.JbpmContext;
import org.jbpm.graph.def.ProcessDefinition;
import org.jbpm.graph.def.Transition;
import org.jbpm.graph.exe.ProcessInstance;
import org.jbpm.taskmgmt.exe.TaskInstance;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;

import com.bjsxt.oa.managers.SystemException;
import com.bjsxt.oa.managers.WorkflowManager;
import com.bjsxt.oa.model.Document;
import com.bjsxt.oa.model.Workflow;

/**
 * 集成方法之一：
 * 
 * 直接注入JbpmConfiguration對象，在獲取JbpmContext對象的時候
 * 將當前session與JbpmContext綁定！
 * @author Administrator
 *
 */
public class WorkflowManagerImpl extends HibernateDaoSupport implements
		WorkflowManager {

	private JbpmConfiguration jbpmConfiguration;
	
	//獲取系統已定義的所有流程名稱列表！
	public List searchAllProcessDefinition() {
		
		JbpmContext context = getJbpmContext();
		
		//獲得已定義的所有流程（最高的版本的記錄，不包含同一個流程的低版本記錄）
		List list = context.getGraphSession().findLatestProcessDefinitions();
		if(list != null && !list.isEmpty()){
			List defs = new ArrayList();
			for (Iterator iter = list.iterator(); iter.hasNext();) {
				ProcessDefinition def = (ProcessDefinition) iter.next();
				defs.add(def.getName());
			}
			return defs;
		}
		
		return null;
	}

	//搜索流轉到用戶username的所有的流程實例（實際上就是公文！）
	public List searchCurrentProcessInstances(String username) {
		
		JbpmContext context = getJbpmContext();
		
		List docIds = new ArrayList();
		
		//從工作流引擎中，根據actor-id的值，獲得分配給這個actor-id的所有任務！
		List taskInstances = context.getTaskMgmtSession().findTaskInstances(username);

		for (Iterator iter = taskInstances.iterator(); iter.hasNext();) {
			TaskInstance ti = (TaskInstance) iter.next();
			
			//如果這個任務是正在等待被完成的狀態
			if(ti.isSignalling()){
				docIds.add(new Integer(ti.getProcessInstance().getKey()));
			}
		}
		
		return docIds;
	}

	//流向下一步！
	public void flowToNextStep(int documentId, String transitionName) {
		Document document = (Document)getHibernateTemplate().load(Document.class, documentId);
		
		JbpmContext context = getJbpmContext();
		
		//根據流程名稱獲得流程定義對象
		ProcessDefinition processDefinition = context.getGraphSession()
			.findLatestProcessDefinition(document.getWorkflow());
		
		//根據流程定義對象以及key值，獲得流程實例
		ProcessInstance processInstance = context.getProcessInstance(processDefinition, ""+documentId);

		if(transitionName == null){
			processInstance.signal();
		}else{
			processInstance.signal(transitionName);
		}
		
		//設置公文的狀態為當前節點的名稱
		document.setStatus(processInstance.getRootToken().getNode().getName());

		//如果已經是終點，則設置公文為已完成狀態
		//當流程到達終點
		if(processInstance.getRootToken().hasEnded()){
			document.setStatus(Document.STATUS_END);
		}
		getHibernateTemplate().update(document);
	}
	
	//獲得文檔的下一步流向，返回流向名稱列表
	public List searchNextSteps(int documentId) {
		
		Document document = (Document)getHibernateTemplate().load(Document.class, documentId);
		
		JbpmContext context = getJbpmContext();
		
		//根據流程名稱獲得流程定義對象
		ProcessDefinition processDefinition = context.getGraphSession()
			.findLatestProcessDefinition(document.getWorkflow());
		
		//根據流程定義對象以及key值，獲得流程實例
		ProcessInstance processInstance = context.getProcessInstance(processDefinition, ""+documentId);
		
		//查看當前流程是否已經結束
		if(processInstance.getRootToken().hasEnded()){
			throw new SystemException("流程已結束");
		}
		
		//獲得當前節點的下一步都有哪些流向
		List list = processInstance.getRootToken().getNode().getLeavingTransitions();
		
		List transitions = new ArrayList();
		
		for (Iterator iter = list.iterator(); iter.hasNext();) {
			
			//獲得流向名稱列表
			Transition transition = (Transition) iter.next();
			transitions.add(transition.getName());
		}
		
		return transitions;
	}

	//刪除流程定義文件
	public void delProcessDefinition(String name) {
		JbpmContext context = getJbpmContext();
		
		//搜索JBPM中所有版本的流程定義記錄
		List allversions = context.getGraphSession().findAllProcessDefinitionVersions(name);
		if(allversions != null){
			
			//逐個刪除
			for (Iterator iter = allversions.iterator(); iter.hasNext();) {
				ProcessDefinition def = (ProcessDefinition) iter.next();
				context.getGraphSession().deleteProcessDefinition(def);
			}
		}
		
		//刪除對應的Workflow對象
		getSession().delete(
				(Workflow)getSession()
					.createQuery("select w from Workflow w where w.name = ?")
					.setParameter(0, name)
					.uniqueResult()
			);
	}

	//部署流程定義
	public void deployProcessDefinition(byte[] processdef, byte[] processimage) {
		if(processdef == null){
			return;
		}
		
		ProcessDefinition def = ProcessDefinition.parseXmlInputStream(new ByteArrayInputStream(processdef));
		JbpmContext context = getJbpmContext();
		
		//將流程定義文件部署到JBPM
		context.deployProcessDefinition(def);
		
		Workflow wf = (Workflow)getSession()
			.createQuery("select w from Workflow w where w.name = ?")
			.setParameter(0, def.getName())
			.uniqueResult();
		if(wf != null){
			wf.setProcessdefinition(processdef);
			wf.setProcessimage(processimage);
			getSession().update(wf);
			return;
		}
		
		wf = new Workflow();
		wf.setName(def.getName());
		wf.setProcessdefinition(processdef);
		wf.setProcessimage(processimage);
		getSession().save(wf);
		
	}
	
	//查找特定流程
	public Workflow findWorkflow(String name) {
		return (Workflow)getSession()
			.createQuery("select w from Workflow w where w.name = ?")
			.setParameter(0, name)
			.uniqueResult();
	}

	//根據公文標識創建流程實例
	public void addProcessInstance(int documentId) {
		JbpmContext context = getJbpmContext();
		Document document = (Document)getHibernateTemplate().load(Document.class, documentId);
		
		//根據公文對應的流程名稱，獲得流程定義對象
		ProcessDefinition processDefinition = context.getGraphSession()
				.findLatestProcessDefinition(document.getWorkflow());
		
		//根據流程定義對象，創建一個流程實例
		ProcessInstance processInstance = new ProcessInstance(processDefinition);
		
		//將流程實例與公文綁定
		processInstance.setKey(""+documentId);
		
		context.save(processInstance);
		
	}

	//刪除流程實例！
	public void delProcessInstance(int documentId) {
		Document document = (Document)getHibernateTemplate().load(Document.class, documentId);
		JbpmContext context = getJbpmContext();
		
		//根據流程名稱獲得流程定義對象
		ProcessDefinition processDefinition = context.getGraphSession()
			.findLatestProcessDefinition(document.getWorkflow());
		
		//根據流程定義對象以及key值，獲得流程實例
		ProcessInstance processInstance = context.getProcessInstance(processDefinition, ""+documentId);
		context.getGraphSession().deleteProcessInstance(processInstance);
		
	}

	//獲取JbpmContext對象
	private JbpmContext getJbpmContext(){
		JbpmContext context = jbpmConfiguration.createJbpmContext();
		
		//關鍵的一個步驟，我們需要將JBPM使用的session對象跟OA系統所使用的
		//session對象整合起來。
		context.setSession(getSession());
		
		return context;
	}

	public void setJbpmConfiguration(JbpmConfiguration jbpmConfiguration) {
		this.jbpmConfiguration = jbpmConfiguration;
	}

}