context: /*
   * Copyright (c) Contributors, http://opensimulator.org/
   * See CONTRIBUTORS.TXT for a full list of copyright holders.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *     * Redistributions of source code must retain the above copyright
   *       notice, this list of conditions and the following disclaimer.
   *     * Redistributions in binary form must reproduce the above copyright
   *       notice, this list of conditions and the following disclaimer in the
   *       documentation and/or other materials provided with the distribution.
   *     * Neither the name of the OpenSimulator Project nor the
   *       names of its contributors may be used to endorse or promote products
   *       derived from this software without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
   * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
   * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED. IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE FOR ANY
   * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
   * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
   * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
   * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  using System;
  using System.Collections.Generic;
  using System.Net;
  using System.Reflection;
  using OpenMetaverse;
  using log4net;
  using OpenSim.Framework;
  using OpenSim.Region.Framework.Interfaces;
  
  namespace OpenSim.Region.Framework.Scenes
  {
      public delegate void RestartSim(RegionInfo thisregion);
  
      /// <summary>
      /// Manager for adding, closing and restarting scenes.
      /// </summary>
      public class SceneManager
      {
          private static readonly ILog m_log = LogManager.GetLogger(MethodBase.GetCurrentMethod().DeclaringType);
  
          public event RestartSim OnRestartSim;
  
          /// <summary>
          /// Fired when either all regions are ready for use or at least one region has become unready for use where
          /// previously all regions were ready.
          /// </summary>
          public event Action<SceneManager> OnRegionsReadyStatusChange;
  
          /// <summary>
          /// Are all regions ready for use?
          /// </summary>
          public bool AllRegionsReady
          {
              get
              {
                  return m_allRegionsReady;
              }
  
              private set
              {
                  if (m_allRegionsReady != value)
                  {
                      m_allRegionsReady = value;
                      Action<SceneManager> handler = OnRegionsReadyStatusChange;
                      if (handler != null)
                      {
                          foreach (Action<SceneManager> d in handler.GetInvocationList())
                          {
                              try
                              {
                                  d(this);
                              }
                              catch (Exception e)
                              {
                                  m_log.ErrorFormat("[SCENE MANAGER]: Delegate for OnRegionsReadyStatusChange failed - continuing {0} - {1}",
                                      e.Message, e.StackTrace);
                              }
                          }
                      }
                  }
              }
          }
          private bool m_allRegionsReady;
  
          private static SceneManager m_instance = null;
          public static SceneManager Instance
          { 
              get {
                  if (m_instance == null)
                      m_instance = new SceneManager();
                  return m_instance;
              } 
          }
  
          private readonly List<Scene> m_localScenes = new List<Scene>();
  
          public List<Scene> Scenes
          {
              get { return new List<Scene>(m_localScenes); }
          }
  
          /// <summary>
          /// Scene selected from the console.
          /// </summary>
          /// <value>
          /// If null, then all scenes are considered selected (signalled as "Root" on the console).
          /// </value>
          public Scene CurrentScene { get; private set; }
  
          public Scene CurrentOrFirstScene
          {
              get
              {
                  if (CurrentScene == null)
                  {
                      lock (m_localScenes)
                      {
                          if (m_localScenes.Count > 0)
                              return m_localScenes[0];
                          else
                              return null;
                      }
                  }
                  else
                  {
                      return CurrentScene;
                  }
              }
          }
  
          public SceneManager()
          {
              m_instance = this;
              m_localScenes = new List<Scene>();
          }
  
          public void Close()
          {
              lock (m_localScenes)
              {
                  for (int i = 0; i < m_localScenes.Count; i++)
                  {
                      m_localScenes[i].Close();
                  }
              }
          }
  
          public void Close(Scene cscene)
          {
              lock (m_localScenes)
              {
                  if (m_localScenes.Contains(cscene))
                  {
                      for (int i = 0; i < m_localScenes.Count; i++)
                      {
                          if (m_localScenes[i].Equals(cscene))
                          {
                              m_localScenes[i].Close();
                          }
                      }
                  }
              }
          }
  
          public void Add(Scene scene)
          {
              lock (m_localScenes)
                  m_localScenes.Add(scene);
  
              scene.OnRestart += HandleRestart;
              scene.EventManager.OnRegionReadyStatusChange += HandleRegionReadyStatusChange;
          }
  
          public void HandleRestart(RegionInfo rdata)
          {
              Scene restartedScene = null;
  
              lock (m_localScenes)
              {
                  for (int i = 0; i < m_localScenes.Count; i++)
                  {
                      if (rdata.RegionName == m_localScenes[i].RegionInfo.RegionName)
                      {
                          restartedScene = m_localScenes[i];
                          m_localScenes.RemoveAt(i);
                          break;
                      }
                  }
              }
  
              // If the currently selected scene has been restarted, then we can't reselect here since we the scene
              // hasn't yet been recreated.  We will have to leave this to the caller.
              if (CurrentScene == restartedScene)
                  CurrentScene = null;
  
              // Send signal to main that we're restarting this sim.
              OnRestartSim(rdata);
          }
  
          private void HandleRegionReadyStatusChange(IScene scene)
          {
              lock (m_localScenes)
                  AllRegionsReady = m_localScenes.TrueForAll(s => s.Ready);
          }
  
          public void SendSimOnlineNotification(ulong regionHandle)
          {
              RegionInfo Result = null;
  
              lock (m_localScenes)
              {
                  for (int i = 0; i < m_localScenes.Count; i++)
                  {
                      if (m_localScenes[i].RegionInfo.RegionHandle == regionHandle)
                      {
                          // Inform other regions to tell their avatar about me
                          Result = m_localScenes[i].RegionInfo;
                      }
                  }
  
  
gt:                 if (Result != null)