/*
 * Copyright 2012 International Business Machines Corp.
 * 
 * See the NOTICE file distributed with this work for additional information
 * regarding copyright ownership. 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.
 */
package com.ibm.jbatch.container.impl;

import java.util.List;
import java.util.logging.Logger;

import javax.batch.runtime.BatchStatus;

import com.ibm.jbatch.container.IController;
import com.ibm.jbatch.container.IExecutionElementController;
import com.ibm.jbatch.container.context.impl.JobContextImpl;
import com.ibm.jbatch.container.jobinstance.RuntimeJobExecution;
import com.ibm.jbatch.container.navigator.ModelNavigator;
import com.ibm.jbatch.container.navigator.NavigatorFactory;
import com.ibm.jbatch.container.services.IPersistenceManagerService;
import com.ibm.jbatch.container.servicesmanager.ServicesManagerImpl;
import com.ibm.jbatch.container.status.ExtendedBatchStatus;
import com.ibm.jbatch.container.status.ExecutionStatus;
import com.ibm.jbatch.jsl.model.Flow;

public class FlowControllerImpl implements IExecutionElementController {

	private final static String CLASSNAME = FlowControllerImpl.class.getName();
	private final static Logger logger = Logger.getLogger(CLASSNAME);

	private final RuntimeJobExecution jobExecution;
	private final JobContextImpl jobContext;

	protected ModelNavigator<Flow> flowNavigator;

	protected Flow flow;
	private long rootJobExecutionId;

	private ExecutionTransitioner transitioner;

	//
	// The currently executing controller, this will only be set to the 
	// local variable reference when we are ready to accept stop events for
	// this execution.
	private volatile IController currentStoppableElementController = null;
	
    private static IPersistenceManagerService _persistenceManagementService = ServicesManagerImpl.getInstance().getPersistenceManagerService();


	public FlowControllerImpl(RuntimeJobExecution jobExecution, Flow flow, long rootJobExecutionId) {
		this.jobExecution = jobExecution;
		this.jobContext = jobExecution.getJobContext();
		this.flowNavigator = NavigatorFactory.createFlowNavigator(flow);
		this.flow = flow;
		this.rootJobExecutionId = rootJobExecutionId;
	}

	@Override
	public ExecutionStatus execute() {
		if (!jobContext.getBatchStatus().equals(BatchStatus.STOPPING)) { 
			transitioner = new ExecutionTransitioner(jobExecution, rootJobExecutionId, flowNavigator);
			return transitioner.doExecutionLoop();
		} else {
			return new ExecutionStatus(ExtendedBatchStatus.JOB_OPERATOR_STOPPING);
		}
	}


	@Override
	public void stop() { 
		// Since this is not a top-level controller, don't try to filter based on existing status.. just pass
		// along the stop().
		IController stoppableElementController = transitioner.getCurrentStoppableElementController();
		if (stoppableElementController != null) {
			stoppableElementController.stop();
		}
	}

    @Override
    public List<Long> getLastRunStepExecutions() {
        return this.transitioner.getStepExecIds();
    }



}