using System.Collections.Generic;

namespace Server.Misc
{
  /*
   * This system prevents the inability for server staff to
   * access their server due to data overflows during login.
   *
   * Whenever a staff character's NetState is disposed right after
   * the login process, the character is moved to and logged out
   * at a "safe" alternative.
   *
   * The location the character was moved from will be reported
   * to the player upon the next successful login.
   *
   * This system does not affect non-staff players.
   */
  public static class PreventInaccess
  {
    public static readonly bool Enabled = true;

    private static readonly LocationInfo[] m_Destinations =
    {
      new LocationInfo(new Point3D(5275, 1163, 0), Map.Felucca), // Jail
      new LocationInfo(new Point3D(5275, 1163, 0), Map.Trammel),
      new LocationInfo(new Point3D(5445, 1153, 0), Map.Felucca), // Green acres
      new LocationInfo(new Point3D(5445, 1153, 0), Map.Trammel)
    };

    private static Dictionary<Mobile, LocationInfo> m_MoveHistory;

    public static void Initialize()
    {
      m_MoveHistory = new Dictionary<Mobile, LocationInfo>();

      if (Enabled)
        EventSink.Login += OnLogin;
    }

    public static void OnLogin(LoginEventArgs e)
    {
      Mobile from = e.Mobile;

      if (from?.AccessLevel < AccessLevel.Counselor)
        return;

      if (HasDisconnected(from))
      {
        if (!m_MoveHistory.ContainsKey(from))
          m_MoveHistory[from] = new LocationInfo(from.Location, from.Map);

        LocationInfo dest = GetRandomDestination();

        from.Location = dest.Location;
        from.Map = dest.Map;
      }
      else if (m_MoveHistory.TryGetValue(from, out LocationInfo orig))
      {
        from.SendMessage("Your character was moved from {0} ({1}) due to a detected client crash.", orig.Location,
          orig.Map);

        m_MoveHistory.Remove(from);
      }
    }

    private static bool HasDisconnected(Mobile m)
    {
      return m.NetState?.Socket == null;
    }

    private static LocationInfo GetRandomDestination()
    {
      return m_Destinations[Utility.Random(m_Destinations.Length)];
    }

    private class LocationInfo
    {
      public LocationInfo(Point3D loc, Map map)
      {
        Location = loc;
        Map = map;
      }

      public Point3D Location{ get; }

      public Map Map{ get; }
    }
  }
}