/*
 * Copyright (c) 1998-2011 Caucho Technology -- all rights reserved
 *
 * This file is part of Resin(R) Open Source
 *
 * Each copy or derived work must preserve the copyright notice and this
 * notice unmodified.
 *
 * Resin Open Source is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * Resin Open Source 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, or any warranty
 * of NON-INFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with Resin Open Source; if not, write to the
 *
 *   Free Software Foundation, Inc.
 *   59 Temple Place, Suite 330
 *   Boston, MA 02111-1307  USA
 *
 * @author Scott Ferguson
 */

package com.caucho.env.deploy;


import java.util.*;
import java.util.concurrent.*;

import com.caucho.cloud.network.NetworkClusterSystem;
import com.caucho.env.service.*;
import com.caucho.inject.Module;

/**
 * Deployment service for detecting changes in a controller, managed
 * by tags.
 */
@Module
public class DeployControllerService extends AbstractResinSubSystem
{
  public static final int START_PRIORITY =
      NetworkClusterSystem.START_PRIORITY_CLUSTER_SERVICE;

  private final ConcurrentHashMap<String,DeployTagItem> _deployMap
    = new ConcurrentHashMap<String,DeployTagItem>();
  
  private final List<DeployTagListener> _tagListeners
    = new CopyOnWriteArrayList<DeployTagListener>();
  
  private final List<DeployUpdateListener> _updateListeners
    = new CopyOnWriteArrayList<DeployUpdateListener>();
  
  public DeployControllerService()
  {
    
  }
  
  public static DeployControllerService createAndAddService()
  {
    ResinSystem system = preCreate(DeployControllerService.class);
      
    DeployControllerService service = new DeployControllerService();
    system.addService(DeployControllerService.class, service);
    
    return service;
  }

  public static DeployControllerService getCurrent()
  {
    return ResinSystem.getCurrentService(DeployControllerService.class);
  }
  
  //
  // tag management
  //
  
  /**
   * Adds a tag
   */
  public DeployTagItem addTag(String tagName)
  {
    DeployTagItem item = new DeployTagItem(tagName);
    
    DeployTagItem oldItem = _deployMap.putIfAbsent(tagName, item);
    if (oldItem != null)
      return oldItem;
    
    for (DeployTagListener listener : _tagListeners) {
      listener.onTagAdd(tagName);
    }
    
    return item;
  }
  
  /**
   * Removes a tag
   */
  public void removeTag(String tagName)
  {
    DeployTagItem oldItem = _deployMap.remove(tagName);
    
    if (oldItem != null) {
      for (DeployTagListener listener : _tagListeners) {
        listener.onTagRemove(tagName);
      }
    }
  }
  
  /**
   * Returns the tags in the deployment
   */
  public Set<String> getTagNames()
  {
    return _deployMap.keySet();
  }
  
  /**
   * Returns the tag item
   */
  public DeployTagItem getTagItem(String tag)
  {
    return _deployMap.get(tag);
  }
  
  //
  // tag listeners
  //
  
  /**
   * Adds a tag listener
   */
  public void addTagListener(DeployTagListener listener)
  {
    _tagListeners.add(listener);
    
    for (String tag : _deployMap.keySet()) {
      listener.onTagAdd(tag);
    }
  }
  
  /**
   * Removes a tag listener
   */
  public void removeTagListener(DeployTagListener listener)
  {
    _tagListeners.remove(listener);
  }
  
  //
  // update listeners
  //
  
  /**
   * Requests an update
   */
  public void update(String tag)
  {
    for (DeployUpdateListener listener : _updateListeners) {
      listener.onUpdate(tag);
    }
  }
  
  /**
   * Adds an update listener
   */
  public void addUpdateListener(DeployUpdateListener listener)
  {
    _updateListeners.add(listener);
  }
  
  /**
   * Removes an update listener
   */
  public void removeUpdateListener(DeployUpdateListener listener)
  {
    _updateListeners.remove(listener);
  }
  
  //
  // NetworkService methods
  //

  /**
   * Returns the start priority order for the deploy service. Currently,
   * it has no dependencies, so it uses the start priority.
   */
  @Override
  public int getStartPriority()
  {
    return START_PRIORITY;
  }
}