/*
 * Copyright 2006 the original author or authors.
 * 
 * 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 org.wamblee.crawler.kiss.scheduling.quartz;

import java.util.Date;
import java.util.List;

import org.quartz.JobDetail;
import org.quartz.Scheduler;
import org.quartz.SchedulerException;
import org.quartz.SchedulerFactory;
import org.quartz.SimpleTrigger;
import org.quartz.Trigger;
import org.quartz.TriggerUtils;
import org.quartz.impl.StdSchedulerFactory;
import org.wamblee.crawler.kiss.scheduling.CrawlerScheduler;

/**
 * Interface to the Quartz scheduler.
 *
 * @author Erik Brakkee
 */
public class QuartzCrawlerScheduler implements CrawlerScheduler {
    
    /**
     * 
     */
    private static final String TRIGGER_NAME = "interval";

    /**
     * 
     */
    private static final String JOB_NAME = "kisscrawler";

    private Scheduler _scheduler; 
    
    private int _intervalInSeconds;

    /**
     * Constructs the quartz interface. 
     * @param aIntervalInSeconds Scheduling interval in seconds. 
     * @throws SchedulerException
     */
    public QuartzCrawlerScheduler(int aIntervalInSeconds) throws SchedulerException { 
        SchedulerFactory schedulerFactory = new StdSchedulerFactory();
        _scheduler = schedulerFactory.getScheduler();
        _intervalInSeconds = aIntervalInSeconds; 
    }
    
    /**
     * Initializes the scheduler.
     * @throws SchedulerException
     */
    public void initialize() throws SchedulerException { 
        _scheduler.start();

        JobDetail jobDetail = new JobDetail(JOB_NAME, null, CrawlerJob.class);
        Trigger trigger = TriggerUtils.makeSecondlyTrigger(_intervalInSeconds);
        //trigger.setStartTime(TriggerUtils.getEvenHourDate(new Date()));
        trigger.setStartTime(new Date());
        trigger.setName(TRIGGER_NAME);

        _scheduler.scheduleJob(jobDetail, trigger);
    }
    
    /* (non-Javadoc)
     * @see org.wamblee.crawler.kiss.scheduling.CrawlerScheduler#isCrawlerRunning()
     */
    public boolean isCrawlerRunning() throws Exception {
        List jobs = _scheduler.getCurrentlyExecutingJobs(); 
        return jobs.size() > 0; 
    }
    
    /* (non-Javadoc)
     * @see org.wamblee.crawler.kiss.scheduling.CrawlerScheduler#scheduleNow()
     */
    public void scheduleNow() throws Exception {
        Trigger trigger = new SimpleTrigger("immediate", null);
        trigger.setJobName(JOB_NAME);
        _scheduler.scheduleJob(trigger);
    }
    
    /**
     * Shuts down the scheduler. 
     * @throws SchedulerException
     */
    public void shutdown() throws SchedulerException { 
        _scheduler.shutdown();
    }
}