class.lock.php

<?php
/*********************************************************************
    class.lock.php

    Ticket lock handle.

    Peter Rotich <peter@osticket.com>
    Copyright (c)  2006-2013 osTicket
    http://www.osticket.com

    Released under the GNU General Public License WITHOUT ANY WARRANTY.
    See LICENSE.TXT for details.

    vim: expandtab sw=4 ts=4 sts=4:
**********************************************************************/

/*
 * Mainly used as a helper...
 */

class TicketLock {
    var $id;
    var $ht;
    
    function TicketLock($id, $tid=0) {
        $this->id=0;
        $this->load($id, $tid);
    }

    function load($id=0, $tid=0) {

        if(!$id && $this->ht['id'])
            $id=$this->ht['id'];

        $sql='SELECT l.*, TIME_TO_SEC(TIMEDIFF(expire,NOW())) as timeleft '
            .' ,IF(s.staff_id IS NULL,"staff",CONCAT_WS(" ", s.lastname, s.firstname)) as staff '
            .' FROM '.TICKET_LOCK_TABLE. ' l '
            .' LEFT JOIN '.STAFF_TABLE.' s ON(s.staff_id=l.staff_id) '
            .' WHERE lock_id='.db_input($id);

        if($tid) 
            $sql.=' AND ticket_id='.db_input($tid);

        if(!($res=db_query($sql)) || !db_num_rows($res))
            return false;

        $this->ht=db_fetch_array($res);
        $this->id=$this->ht['id']=$this->ht['lock_id'];
        $this->ht['expiretime']=time()+$this->ht['timeleft'];
        
        return true;
    }
  
    function reload() {
        return $this->load();
    }

    function getId() {
        return $this->id;
    }

    function getStaffId() {
        return $this->ht['staff_id'];
    }

    function getStaffName() {
        return $this->ht['staff'];
    }

    function getCreateTime() {
        return $this->ht['created'];
    }

    function getExpireTime() {
        return $this->ht['expire'];
    }
    //Get remaiming time before the lock expires
    function getTime() {
        return $this->isExpired()?0:($this->ht['expiretime']-time());
    }

    //Should we be doing realtime check here? (Ans: not really....expiretime is local & based on loadtime)
    function isExpired() {
        return (time()>$this->ht['expiretime']);
    }
   
    //Renew existing lock.
    function renew($lockTime=0) {

        if(!$lockTime || !is_numeric($lockTime)) //XXX: test to  make it works.
            $lockTime = '(TIME_TO_SEC(TIMEDIFF(expire,created))/60)';
            

        $sql='UPDATE '.TICKET_LOCK_TABLE
            .' SET expire=DATE_ADD(NOW(),INTERVAL '.$lockTime.' MINUTE) '
            .' WHERE lock_id='.db_input($this->getId());
        //echo $sql;
        if(!db_query($sql) || !db_affected_rows())
            return false;
        
        $this->reload();
        
        return true;
    }

    //release aka delete a lock.
    function release() {
        //FORCED release - we don't give a ....
        $sql='DELETE FROM '.TICKET_LOCK_TABLE.' WHERE lock_id='.db_input($this->getId()).' LIMIT 1';
        return (db_query($sql) && db_affected_rows());
    }

    /* ----------------------- Static functions ---------------------------*/
    function lookup($id, $tid) {
        return ($id  && ($lock = new TicketLock($id,$tid)) && $lock->getId()==$id)?$lock:null;
    }

    //Create a ticket lock...this function assumes the caller checked for access & validity of ticket & staff x-ship.    
    function acquire($ticketId, $staffId, $lockTime) {

        if(!$ticketId or !$staffId or !$lockTime)
            return 0;


        //Cleanup any expired locks on the ticket.
        db_query('DELETE FROM '.TICKET_LOCK_TABLE.' WHERE ticket_id='.db_input($ticketId).' AND expire<NOW()');
        //create the new lock.
        $sql='INSERT IGNORE INTO '.TICKET_LOCK_TABLE.' SET created=NOW() '
            .',ticket_id='.db_input($ticketId)
            .',staff_id='.db_input($staffId)
            .',expire=DATE_ADD(NOW(),INTERVAL '.$lockTime.' MINUTE) ';

        return db_query($sql)?db_insert_id():0;
    }

    function create($ticketId, $staffId, $lockTime) {
        if(($id=self::acquire($ticketId, $staffId, $lockTime)))
            return self::lookup($id);
    }

    //Simply remove ALL locks a user (staff) holds on a ticket(s).
    function removeStaffLocks($staffId, $ticketId=0) {
        $sql='DELETE FROM '.TICKET_LOCK_TABLE.' WHERE staff_id='.db_input($staffId);
        if($ticketId)
            $sql.=' AND ticket_id='.db_input($ticketId);

        return db_query($sql);
    }

    //Called  via cron 
    function cleanup() {
        //Cleanup any expired locks.
        db_query('DELETE FROM '.TICKET_LOCK_TABLE.' WHERE expire<NOW()');
        @db_query('OPTIMIZE TABLE '.TICKET_LOCK_TABLE);
    }
}
?>