<?php
/**
 * the last known user to change this file in the repository  <$LastChangedBy$>
 * @author $Author$ Foxsee@aliyun.com
 * @copyright  ©2003-2103 phpwind.com
 * @license http://www.phpwind.com
 * @version $Id$ 
 * @package 
 */
class PwProcessService {
	
	/**
	 * 判断一个进程是否存在
	 * Enter description here ...
	 * @param string $flag
	 */
	public function isProcess($flag) {
		$time = Pw::getTime();
		$process = Wekit::load('process.PwProcess')->getProcess($flag);
		if (!$process) return false;
		if ($process['expired_time'] < $time) return false;
		return true;
	}
	 
	/**
	 * 对进程进行加锁
	 * Enter description here ...
	 * @param string $flag
	 * @param int $expiredTime
	 * @return bool
	 */
	public function lockProcess($flag, $expiredTime = 30) {
		$ds = Wekit::load('process.PwProcess');
		$time = Pw::getTime();
		$expiredTime += $time;
		$process = $ds->getProcess($flag);
		$ds->deleteProcessByTime($time - 3000);
		if ($process &&  $process['expired_time'] > $expiredTime) {
			return false;
		} else {
			return $ds->replaceProcess($flag, $expiredTime);
		}
	}
	
	/**
	 * 对进程进行解锁
	 * Enter description here ...
	 * @param string $flag
	 */
	public function unlockProcess($flag) {
		$ds = Wekit::load('process.PwProcess');
		$ds->deleteProcess($flag);
	}
	
}
?>