/*
Copyright (c) OpenSim project, http://osgrid.org/


* All rights reserved.
*
* 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 <organization> 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 <copyright holder> ``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 <copyright holder> 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.Text;
using System.IO;
using System.Threading;
using System.Net;
using System.Net.Sockets;
using System.Timers;
using System.Reflection;
using System.Collections;
using System.Collections.Generic;
using libsecondlife;
using libsecondlife.Packets;
using OpenSim.world;
using OpenSim.GridServers;
using OpenSim.Assets;
using ServerConsole;
using PhysicsSystem;

namespace OpenSim
{
	/// <summary>
	/// Description of MainForm.
	/// </summary>
	public class OpenSim_Main
	{
		public static OpenSim_Main sim;
		public static SimConfig cfg;
		public static World local_world;
		public static Grid gridServers;
		
		public static Socket Server;
		private static IPEndPoint ServerIncoming;
		private static byte[] RecvBuffer = new byte[4096];
		private byte[] ZeroBuffer = new byte[8192];
		private static IPEndPoint ipeSender;
		private static EndPoint epSender;
		private static AsyncCallback ReceivedData;

		public AssetCache assetCache;
		public DateTime startuptime;
		public Dictionary<EndPoint, OpenSimClient> ClientThreads = new Dictionary<EndPoint, OpenSimClient>();
		private PhysicsManager physManager;
		private System.Timers.Timer timer1 = new System.Timers.Timer();
		private string ConfigDll = "SimConfig.dll";
		public bool sandbox = false;
		public bool loginserver = false;
		
		[STAThread]
		public static void Main( string[] args )
		{
			Console.WriteLine("OpenSim " + VersionInfo.Version + "\n");
			Console.WriteLine("Starting...\n");
			ServerConsole.MainConsole.Instance = new MServerConsole(ServerConsole.ConsoleBase.ConsoleType.Local,"",0);
			
			sim = new OpenSim_Main();
			
			for (int i = 0; i < args.Length; i++)
			{
				if(args[i] == "-sandbox")
				{
					sim.sandbox = true;
				}
				if(args[i] == "-loginserver")
				{
					sim.loginserver = true;
				}
			}
			
			OpenSim_Main.gridServers = new Grid();
			if(sim.sandbox)
			{
				OpenSim_Main.gridServers.AssetDll = "LocalGridServers.dll";
				OpenSim_Main.gridServers.GridDll = "LocalGridServers.dll";
				OpenSim_Main.gridServers.LoadPlugins();
				ServerConsole.MainConsole.Instance.WriteLine("Starting in Sandbox mode");
			}
			else
			{
				OpenSim_Main.gridServers.AssetDll = "RemoteGridServers.dll";
				OpenSim_Main.gridServers.GridDll = "RemoteGridServers.dll";
				OpenSim_Main.gridServers.LoadPlugins();
				ServerConsole.MainConsole.Instance.WriteLine("Starting in Grid mode");
			}
			
			if(sim.loginserver && sim.sandbox)
			{
				LoginServer loginServer = new LoginServer(OpenSim_Main.gridServers.GridServer);
				loginServer.Startup();
			}
			sim.assetCache = new AssetCache(OpenSim_Main.gridServers.AssetServer);
			
			sim.Startup();
			
			while(true) {
				ServerConsole.MainConsole.Instance.MainConsolePrompt();
			}
		}

		private OpenSim_Main() {
		}
		
		private void Startup() {
			startuptime=DateTime.Now;
			timer1.Enabled = true;
			timer1.Interval = 100;
			timer1.Elapsed +=new ElapsedEventHandler( this.Timer1Tick );
			
			// We check our local database first, then the grid for config options
			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:Startup() - Loading configuration");
			cfg = this.LoadConfigDll(this.ConfigDll);
			cfg.InitConfig();
			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:Startup() - Contacting gridserver");
			cfg.LoadFromGrid();

			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:Startup() - We are " + cfg.RegionName + " at " + cfg.RegionLocX.ToString() + "," + cfg.RegionLocY.ToString());
			ServerConsole.MainConsole.Instance.WriteLine("Initialising world");
			local_world = cfg.LoadWorld();
			
			this.physManager = new PhysicsSystem.PhysicsManager();
			this.physManager.LoadPlugins();
			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:Startup() - Starting up messaging system");
			local_world.PhysScene = this.physManager.GetPhysicsScene("PhysX"); //should be reading from the config file what physics engine to use
			local_world.PhysScene.SetTerrain(local_world.LandMap);
			OpenSim_Main.gridServers.AssetServer.SetServerInfo(OpenSim_Main.cfg.AssetURL, OpenSim_Main.cfg.AssetSendKey);
			OpenSim_Main.gridServers.GridServer.SetServerInfo(OpenSim_Main.cfg.GridURL, OpenSim_Main.cfg.GridSendKey);
			
			MainServerListener();

		}
		
		private SimConfig LoadConfigDll(string dllName)
		{
			Assembly pluginAssembly = Assembly.LoadFrom(dllName);
			SimConfig config = null;
			
			foreach (Type pluginType in pluginAssembly.GetTypes())
			{
				if (pluginType.IsPublic)
				{
					if (!pluginType.IsAbstract)
					{
						Type typeInterface = pluginType.GetInterface("ISimConfig", true);
						
						if (typeInterface != null)
						{
							ISimConfig plug = (ISimConfig)Activator.CreateInstance(pluginAssembly.GetType(pluginType.ToString()));
							config = plug.GetConfigObject();
							break;
						}
						
						typeInterface = null;
					}
				}
			}
			pluginAssembly = null;
			return config;
		}

		private void OnReceivedData(IAsyncResult result) {
			ipeSender = new IPEndPoint(IPAddress.Any, 0);
			epSender = (EndPoint)ipeSender;
			Packet packet = null;
			int numBytes = Server.EndReceiveFrom(result, ref epSender);
			int packetEnd = numBytes - 1;
			packet = Packet.BuildPacket(RecvBuffer, ref packetEnd, ZeroBuffer);
			
			// This is either a new client or a packet to send to an old one
			if(ClientThreads.ContainsKey(epSender)) {
				ClientThreads[epSender].InPacket(packet);
			} else if( packet.Type == PacketType.UseCircuitCode ) { // new client
				OpenSimClient newuser = new OpenSimClient(epSender,(UseCircuitCodePacket)packet);
				ClientThreads.Add(epSender, newuser);
			} else { // invalid client
				Console.Error.WriteLine("Main.cs:OnReceivedData() - WARNING: Got a packet from an invalid client - " + epSender.ToString());
			}
			Server.BeginReceiveFrom(RecvBuffer, 0, RecvBuffer.Length, SocketFlags.None, ref epSender, ReceivedData, null);
		}

		private void MainServerListener() {
			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:MainServerListener() - New thread started");
			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:MainServerListener() - Opening UDP socket on " + cfg.IPListenAddr + ":" + cfg.IPListenPort);

			ServerIncoming = new IPEndPoint(IPAddress.Any, cfg.IPListenPort);
			Server = new Socket(AddressFamily.InterNetwork, SocketType.Dgram, ProtocolType.Udp);
			Server.Bind(ServerIncoming);
			
			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:MainServerListener() - UDP socket bound, getting ready to listen");

			ipeSender = new IPEndPoint(IPAddress.Any, 0);
			epSender = (EndPoint) ipeSender;
			ReceivedData = new AsyncCallback(this.OnReceivedData);
			Server.BeginReceiveFrom(RecvBuffer, 0, RecvBuffer.Length, SocketFlags.None, ref epSender, ReceivedData, null);
			
			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:MainServerListener() - Listening...");
			
		}
		
		public static void Shutdown() {
			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:Shutdown() - Closing all threads");
			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:Shutdown() - Killing listener thread");
			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:Shutdown() - Killing clients");
			// IMPLEMENT THIS
			ServerConsole.MainConsole.Instance.WriteLine("Main.cs:Shutdown() - Closing console and terminating");
			ServerConsole.MainConsole.Instance.Close();
			Environment.Exit(0);
		}
		
		void Timer1Tick( object sender, System.EventArgs e )
		{
			
			local_world.Update();
		}
	}
	
	public class Grid
	{
		public IAssetServer AssetServer;
		public IGridServer GridServer;
		public string AssetDll = "";
		public string GridDll = "";
		
		public Grid()
		{
		}
		
		public void LoadPlugins()
		{
			this.AssetServer = this.LoadAssetDll(this.AssetDll);
			this.GridServer = this.LoadGridDll(this.GridDll);
		}
		
		private IAssetServer LoadAssetDll(string dllName)
		{
			Assembly pluginAssembly = Assembly.LoadFrom(dllName);
			IAssetServer server = null;
			
			foreach (Type pluginType in pluginAssembly.GetTypes())
			{
				if (pluginType.IsPublic)
				{
					if (!pluginType.IsAbstract)
					{
						Type typeInterface = pluginType.GetInterface("IAssetPlugin", true);
						
						if (typeInterface != null)
						{
							IAssetPlugin plug = (IAssetPlugin)Activator.CreateInstance(pluginAssembly.GetType(pluginType.ToString()));
							server = plug.GetAssetServer();
							break;
						}
						
						typeInterface = null;
					}
				}
			}
			pluginAssembly = null;
			return server;
		}
		
		private IGridServer LoadGridDll(string dllName)
		{
			Assembly pluginAssembly = Assembly.LoadFrom(dllName);
			IGridServer server = null;
			
			foreach (Type pluginType in pluginAssembly.GetTypes())
			{
				if (pluginType.IsPublic)
				{
					if (!pluginType.IsAbstract)
					{
						Type typeInterface = pluginType.GetInterface("IGridPlugin", true);
						
						if (typeInterface != null)
						{
							IGridPlugin plug = (IGridPlugin)Activator.CreateInstance(pluginAssembly.GetType(pluginType.ToString()));
							server = plug.GetGridServer();
							break;
						}
						
						typeInterface = null;
					}
				}
			}
			pluginAssembly = null;
			return server;
		}
	}
}