content: /*
   This file is part of the HeavenMS MapleStory Server
   Copyleft (L) 2016 - 2019 RonanLana
  
   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU Affero General Public License as
   published by the Free Software Foundation version 3 as published by
   the Free Software Foundation. You may not use, modify or distribute
   this program under any other version of the GNU Affero General Public
   License.
  
   This program 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 Affero General Public License for more details.
  
   You should have received a copy of the GNU Affero General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
   */
  package scripting.event.scheduler;
  
  import config.YamlConfig;
  import java.util.HashMap;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Map;
  import java.util.Map.Entry;
  import java.util.concurrent.ScheduledFuture;
  import server.TimerManager;
  import net.server.Server;
  import net.server.audit.LockCollector;
  import net.server.audit.locks.MonitoredLockType;
  import net.server.audit.locks.MonitoredReentrantLock;
  import net.server.audit.locks.factory.MonitoredReentrantLockFactory;
  import server.ThreadManager;
  
  /**
   *
   * @author Ronan
   */
  public class EventScriptScheduler {
  
      private boolean disposed = false;
      private int idleProcs = 0;
      private Map<Runnable, Long> registeredEntries = new HashMap<>();
  
      private ScheduledFuture<?> schedulerTask = null;
      private MonitoredReentrantLock schedulerLock;
      private Runnable monitorTask = new Runnable() {
          @Override
          public void run() {
              runBaseSchedule();
          }
      };
  
      public EventScriptScheduler() {
          schedulerLock = MonitoredReentrantLockFactory.createLock(MonitoredLockType.EM_SCHDL, true);
      }
  
      private void runBaseSchedule() {
          List<Runnable> toRemove;
          Map<Runnable, Long> registeredEntriesCopy;
  
          schedulerLock.lock();
          try {
              if (registeredEntries.isEmpty()) {
                  idleProcs++;
  
                  if (idleProcs >= YamlConfig.config.server.MOB_STATUS_MONITOR_LIFE) {
                      if (schedulerTask != null) {
                          schedulerTask.cancel(false);
                          schedulerTask = null;
                      }
                  }
  
                  return;
              }
  
              idleProcs = 0;
              registeredEntriesCopy = new HashMap<>(registeredEntries);
          } finally {
              schedulerLock.unlock();
          }
  
          long timeNow = Server.getInstance().getCurrentTime();
          toRemove = new LinkedList<>();
          for (Entry<Runnable, Long> rmd : registeredEntriesCopy.entrySet()) {
              if (rmd.getValue() < timeNow) {
                  Runnable r = rmd.getKey();
  
                  r.run();  // runs the scheduled action
                  toRemove.add(r);
              }
          }
  
          if (!toRemove.isEmpty()) {
              schedulerLock.lock();
              try {
                  for (Runnable r : toRemove) {
                      registeredEntries.remove(r);
                  }
              } finally {
                  schedulerLock.unlock();
              }
          }
      }
  
      public void registerEntry(final Runnable scheduledAction, final long duration) {
  
          ThreadManager.getInstance().newTask(new Runnable() {
              @Override
              public void run() {
                  schedulerLock.lock();
                  try {
                      idleProcs = 0;
                      if (schedulerTask == null) {
                          if (disposed) {
                              return;
                          }
  
                          schedulerTask = TimerManager.getInstance().register(monitorTask, YamlConfig.config.server.MOB_STATUS_MONITOR_PROC, YamlConfig.config.server.MOB_STATUS_MONITOR_PROC);
                      }
  
                      registeredEntries.put(scheduledAction, Server.getInstance().getCurrentTime() + duration);
                  } finally {
                      schedulerLock.unlock();
                  }
              }
          });
      }
  
      public void cancelEntry(final Runnable scheduledAction) {
  
          ThreadManager.getInstance().newTask(new Runnable() {
              @Override
              public void run() {
                  schedulerLock.lock();
                  try {
                      registeredEntries.remove(scheduledAction);
                  } finally {
                      schedulerLock.unlock();
                  }
              }
          });
      }
  
      public void dispose() {
  
          ThreadManager.getInstance().newTask(new Runnable() {
              @Override
              public void run() {
                  schedulerLock.lock();
                  try {
                      if (schedulerTask != null) {
                          schedulerTask.cancel(false);
                          schedulerTask = null;
                      }
  
                      registeredEntries.clear();
                      disposed = true;
                  } finally {
                      schedulerLock.unlock();
                  }
  
                  disposeLocks();
              }
          });
      }
  
      private void disposeLocks() {
          LockCollector.getInstance().registerDisposeAction(new Runnable() {
              @Override
              public void run() {
                  emptyLocks();
              }
          });
      }
  
      private void emptyLocks() {
          schedulerLock = schedulerLock.dispose();
      }
  }
  