/*
 * JBoss, Home of Professional Open Source
 * Copyright 2005, JBoss Inc., and individual contributors as indicated
 * by the @authors tag. See the copyright.txt in the distribution for a
 * full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.jboss.varia.scheduler;

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.StringTokenizer;

import javax.management.JMException;
import javax.management.MBeanServer;
import javax.management.MalformedObjectNameException;
import javax.management.ObjectName;

/**
 * This Provider adds a single Schedule to the Schedule Manager
 * but you can create more than one of this MBeans and each will
 * add a different Schedule even when the use the same Target.
 * ATTENTION: This is the provider you used in the older Scheduler
 * when you used a MBean as target.
 *
 * @author <a href="mailto:andreas@jboss.org">Andreas Schaefer</a>
 * @author <a href="mailto:dimitris@jboss.org">Dimitris Andreadis</a>
 * @version $Revision: 1.1.2.3 $
 */
public class SingleScheduleProvider extends AbstractScheduleProvider
   implements SingleScheduleProviderMBean
{

   // -------------------------------------------------------------------------
   // Constants
   // -------------------------------------------------------------------------
   
   // -------------------------------------------------------------------------
   // Members
   // -------------------------------------------------------------------------
   
   private ObjectName mSchedulableMBean;
   private String mSchedulableMBeanMethod;
   private String mSchedulableMBeanMethodName;
   private String[] mMethodSignature = new String[ 0 ];
   
   private SimpleDateFormat mDateFormatter;
   private Date mStartDate;
   private String mStartDateString;
   private long mSchedulePeriod;
   private long mInitialRepetitions;
   
   /** The ID of the Schedule used later to remove it later */
   private int mScheduleID;
   
   // -------------------------------------------------------------------------
   // Constructors
   // -------------------------------------------------------------------------
   
   /**
    * Default (no-args) Constructor
    */
   public SingleScheduleProvider()
   {
   }
   
   // -------------------------------------------------------------------------
   // SchedulerMBean Methods
   // -------------------------------------------------------------------------
   
   public void startProviding() throws JMException
   {
      mScheduleID = addSchedule(
         mSchedulableMBean,
         mSchedulableMBeanMethodName,
         mMethodSignature,
         mStartDate,
         mSchedulePeriod,
         (int) mInitialRepetitions
      );
   }
   
   public void stopProviding()
   {
      try
      {
         removeSchedule( mScheduleID );
      }
      catch (JMException jme)
      {
         log.error( "Could not remove Schedule in stop providing", jme );
      }
   }
   
   /**
    * @jmx:managed-attribute
    *
    * @return Object Name of the Target MBean for the timer notifications
    */
   public String getTargetName()
   {
      return mSchedulableMBean == null ? null : mSchedulableMBean.toString();
   }
   
   /**
    * Sets the fully qualified JMX MBean Object Name of the Schedulable MBean to be called.
    *
    * @jmx:managed-attribute
    *
    * @param pTargetObjectName JMX MBean Object Name which should be called.
    *
    * @throws IllegalArgumentException If the given value is an valid Object Name.
    */
   public void setTargetName(String pTargetObjectName) throws IllegalArgumentException
   {
      if (pTargetObjectName == null)
      {
         throw new IllegalArgumentException("Schedulable MBean must be specified");
      }
      try
      {
         mSchedulableMBean = new ObjectName( pTargetObjectName );
      }
      catch(MalformedObjectNameException mone)
      {
         log.error("Schedulable MBean Object Name is malformed", mone);
         throw new IllegalArgumentException("Schedulable MBean is not correctly formatted");
      }
   }
   
   /**
    * @return Method description of the target MBean to be called
    *
    * @jmx:managed-attribute
    */
   public String getTargetMethod()
   {
      return mSchedulableMBeanMethod;
   }
   
   /**
    * Sets the method name to be called on the Schedulable MBean. It can optionally be
    * followed by an opening bracket, list of attributes (see below) and a closing bracket.
    * The list of attributes can contain:
    * <ul>
    * <li>NOTIFICATION which will be replaced by the timers notification instance
    *     (javax.management.Notification)</li>
    * <li>DATE which will be replaced by the date of the notification call
    *     (java.util.Date)</li>
    * <li>REPETITIONS which will be replaced by the number of remaining repetitions
    *     (long)</li>
    * <li>SCHEDULER_NAME which will be replaced by the Object Name of the Scheduler
    *     (javax.management.ObjectName)</li>
    * <li>any full qualified Class name which the Scheduler will be set a "null" value
    *     for it</li>
    * </ul>
    * <br>
    * An example could be: "doSomething( NOTIFICATION, REPETITIONS, java.lang.String )"
    * where the Scheduler will pass the timer's notification instance, the remaining
    * repetitions as int and a null to the MBean's doSomething() method which must
    * have the following signature: doSomething( javax.management.Notification, long,
    * java.lang.String ).
    *
    * @jmx:managed-attribute
    *
    * @param pTargetMethod Name of the method to be called optional followed
    *                                by method arguments (see above).
    *
    * @throws IllegalArgumentException If the given value is not of the right
    *                                   format
    */
   public void setTargetMethod(String pTargetMethod) throws IllegalArgumentException
   {
      if (pTargetMethod == null)
      {
         mSchedulableMBeanMethod = null;
         return;
      }
      int lIndex = pTargetMethod.indexOf('(');
      String lMethodName = "";
      if( lIndex < 0 )
      {
         lMethodName = pTargetMethod.trim();
         mMethodSignature = new String[ 0 ];
      }
      else
      if( lIndex > 0 )
      {
         lMethodName = pTargetMethod.substring(0, lIndex).trim();
      }
      if (lMethodName.equals(""))
      {
         lMethodName = "perform";
      }
      if (lIndex >= 0)
      {
         int lIndex2 = pTargetMethod.indexOf(')');
         if (lIndex2 < lIndex)
         {
            throw new IllegalArgumentException("Schedulable MBean Method: closing bracket must be after opening bracket");
         }
         if (lIndex2 < pTargetMethod.length() - 1)
         {
            String lRest = pTargetMethod.substring(lIndex2 + 1).trim();
            if (lRest.length() > 0)
            {
               throw new IllegalArgumentException("Schedulable MBean Method: nothing should be after closing bracket");
            }
         }
         String lArguments = pTargetMethod.substring(lIndex + 1, lIndex2).trim();
         if (lArguments.equals(""))
         {
            mMethodSignature = new String[0];
         }
         else
         {
            StringTokenizer lTokenizer = new StringTokenizer(lArguments, ",");
            mMethodSignature = new String[lTokenizer.countTokens()];
            for (int i = 0; lTokenizer.hasMoreTokens(); i++)
            {
               mMethodSignature[i] = lTokenizer.nextToken().trim();
            }
         }
      }
      mSchedulableMBeanMethodName = lMethodName;
      mSchedulableMBeanMethod = pTargetMethod;
   }
   
   /**
    * @jmx:managed-attribute
    *
    * @return Schedule Period between two scheduled calls in Milliseconds. It will always
    *         be bigger than 0 except it returns -1 then the schedule is stopped.
    */
   public long getPeriod()
   {
      return mSchedulePeriod;
   }

   /**
    * Sets the Schedule Period between two scheduled call.
    *
    * @jmx:managed-attribute
    *
    * @param pPeriod Time between to scheduled calls (after the initial call) in Milliseconds.
    *                This value must be bigger than 0.
    *
    * @throws IllegalArgumentException If the given value is less or equal than 0
    */
   public void setPeriod(long pPeriod)
   {
      if (pPeriod <= 0)
      {
         throw new IllegalArgumentException("Schedulable Period may be not less or equals than 0");
      }
      mSchedulePeriod = pPeriod;
   }

   /**
    * @jmx:managed-attribute
    *
    * @return the date format
    */
   public String getDateFormat()
   {
      if (mDateFormatter == null)
         mDateFormatter = new SimpleDateFormat();
      
      return mDateFormatter.toPattern();
   }
   
   /** 
    * Sets the date format used to parse date/times
    *
    * @jmx:managed-attribute
    *
    * @param dateFormat The date format when empty or null the locale is used to parse dates
    */
   public void setDateFormat(String dateFormat)
   {
      if (dateFormat == null || dateFormat.trim().length() == 0)
         mDateFormatter = new SimpleDateFormat();
      else
         mDateFormatter = new SimpleDateFormat(dateFormat);
   }
   
   /**
    * @jmx:managed-attribute
    *
    * @return Date (and time) of the first scheduled. For value see {@link #setInitialStartDate} 
    *         method.
    */
   public String getStartDate()
   {
      return mStartDateString;
   }
   
   /** 
    * Sets the first scheduled call. If the date is in the past the scheduler tries to find the
    * next available start date.
    *
    * @jmx:managed-attribute
    *
    * @param pStartDate Date when the initial call is scheduled. It can be either:
    *                   <ul>
    *                      <li>
    *                         NOW: date will be the current date (new Date()) plus 1 seconds
    *                      </li><li>
    *                         Date as String able to be parsed by SimpleDateFormat with default format
    *                      </li><li>
    *                         Date as String parsed using the date format attribute
    *                      </li><li>
    *                         Milliseconds since 1/1/1970
    *                      </li>
    *                   </ul>
    *                   If the date is in the past the Scheduler
    *                   will search a start date in the future with respect to the initial repe-
    *                   titions and the period between calls. This means that when you restart
    *                   the MBean (restarting JBoss etc.) it will start at the next scheduled
    *                   time. When no start date is available in the future the Scheduler will
    *                   not start.<br>
    *                   Example: if you start your Schedulable everyday at Noon and you restart
    *                   your JBoss server then it will start at the next Noon (the same if started
    *                   before Noon or the next day if start after Noon).
    */
   public void setStartDate(String pStartDate)
   {
      mStartDateString = pStartDate == null ? "" : pStartDate.trim();
      if (mStartDateString.equals(""))
      {
         mStartDate = new Date(0);
      }
      else if (mStartDateString.equals("NOW"))
      {
         mStartDate = new Date(new Date().getTime() + 1000);
      }
      else
      {
         try
         {
            long lDate = new Long(pStartDate).longValue();
            mStartDate = new Date(lDate);
         }
         catch (Exception e)
         {
            try
            {
               if (mDateFormatter == null)
               {
                  mDateFormatter = new SimpleDateFormat();
               }
               mStartDate = mDateFormatter.parse(mStartDateString);
            }
            catch (Exception e2)
            {
               log.error ("Could not parse given date string: " + mStartDateString, e2);
               throw new IllegalArgumentException("Schedulable Date is not of correct format");
            }
         }
      }
      log.debug("Initial Start Date is set to: " + mStartDate);
   }

   /**
    * @jmx:managed-attribute
    *
    * @return Number of scheduled calls initially. If -1 then there is not limit.
    */
   public long getRepetitions()
   {
      return mInitialRepetitions;
   }

   /**
    * Sets the initial number of scheduled calls.
    *
    * @jmx:managed-attribute
    *
    * @param pNumberOfCalls Initial Number of scheduled calls. If -1 then the number
    *                       is unlimted.
    *
    * @throws IllegalArgumentException If the given value is less or equal than 0
    */
   public void setRepetitions(long pNumberOfCalls)
   {
      if (pNumberOfCalls <= 0)
      {
         pNumberOfCalls = -1;
      }
      mInitialRepetitions = pNumberOfCalls;
   }
   
   // -------------------------------------------------------------------------
   // Methods
   // -------------------------------------------------------------------------
   
   public ObjectName getObjectName(MBeanServer pServer, ObjectName pName)
      throws MalformedObjectNameException
   {
      return pName == null ? SingleScheduleProviderMBean.OBJECT_NAME : pName;
   }
}
