Genesis UDP Server and Client

/*
 * Genesis Socket Server and Client
 * (C)Copyright 2005/2006 Robert Harwood <robharwood@runbox.com>
 * 
 * Please see included license.txt file for information on redistribution and usage.
 */
using System;
using System.Net;

namespace GenesisCore
{
	/// <summary>
	/// Represents the public interface for a connection.
	/// </summary>
	public interface IConnection
	{
		/// <summary>
		/// Gets the encryption key being used for the connection (emptry string means no encryption).
		/// </summary>
		string EncryptionKey
		{
			get;
		}

		/// <summary>
		/// On a connection created at the client side, gets the request id generated when the connection was
		/// first requested to the server.
		/// </summary>
		string RequestID
		{
			get;
		}

		/// <summary>
		/// Gets the remote end point representing the remote computer for this connection.
		/// </summary>
		IPEndPoint RemoteEP
		{
			get;
		}

		/// <summary>
		/// Gets the ID of the last sent unreliable packet.
		/// </summary>
		uint LastSentPacket
		{
			get;
		}

		/// <summary>
		/// Gets the ID of the last received unreliable packet.
		/// </summary>
		uint LastReceivedPacket
		{
			get;
		}

		/// <summary>
		/// Gets the ID of the last sent reliable packet.
		/// </summary>
		uint LastSentPacketR
		{
			get;
		}

		/// <summary>
		/// Gets the ID of the last received reliable packet.
		/// </summary>
		uint LastReceivedPacketR
		{
			get;
		}

		/// <summary>
		/// Gets the ID of the last received sequenced unreliable packet.
		/// </summary>
		uint LastReceivedPacketSeq
		{
			get;
		}

		/// <summary>
		/// Gets a value that shows whether or not this connection is authenticated.
		/// </summary>
		bool Authed
		{
			get;
		}

		/// <summary>
		/// Gets a value that determines whether the connection is a server or client connection.
		/// </summary>
		bool Server
		{
			get;
		}

		/// <summary>
		/// Gets a value that determines when the connection will be regarded as having "timed out".
		/// </summary>
		DateTime TimeoutTime
		{
			get;
		}

		/// <summary>
		/// Gets or sets an object that can be set to anything specific to the user application and connection.
		/// </summary>
		object UserObject
		{
			get;
			set;
		}

		/// <summary>
		/// Sends an unreliable command to the remote client.
		/// </summary>
		int SendUnreliableCommand(byte flags, string opcode, string[] fields);

		/// <summary>
		/// Sends a reliable command to the remote client.
		/// </summary>
		int SendReliableCommand(byte flags, string opcode, string[] fields);
	}

	/// <summary>
	/// Interface that represents a command sent over the network.
	/// </summary>
	public interface ICommand
	{
		/// <summary>
		/// Gets the 2 byte opcode for the command message.
		/// </summary>
		string OPCode
		{
			get;
		}

		/// <summary>
		/// Gets the unique ID of the command packet, the number is only unique for the connection it occured in.
		/// </summary>
		uint SequenceNum
		{
			get;
		}

		/// <summary>
		/// Gets various properties of the command (such as whether or not it is sequenced).
		/// </summary>
		byte Flags
		{
			get;
		}

		/// <summary>
		/// The number of data fields in the command.
		/// </summary>
		short NumFields
		{
			get;
		}

		/// <summary>
		/// The size of each data field within the command.
		/// </summary>
		short[] FieldSizes
		{
			get;
		}

		/// <summary>
		/// The actual data fields within the command.
		/// </summary>
		string[] Fields
		{
			get;
		}

		/// <summary>
		/// Gets a single string containing all of hte data fields concatenated.
		/// </summary>
		string AllFields
		{
			get;
		}
	}

	public interface IGenesisUDP
	{
		/// <summary>
		/// Fired when a debug message is generated by the UDP server (DEBUG builds only).
		/// </summary>
		event DebugHandler OnDebugMessage;

		/// <summary>
		/// Fired when some data is read from the UDP socket, allows access to the raw information.
		/// </summary>
		event ReceivedHandler OnDataReceived;

		/// <summary>
		/// Fired when the UDP server starts or stops listening.
		/// </summary>
		event ListenHandler OnListenStateChanged;

		/// <summary>
		/// Fired when the UDP socket generates an error.
		/// </summary>
		event SocketErrorHandler OnSocketError;

		/// <summary>
		/// Fired when a command arrives that has no connection related to it (such as connection requests).
		/// </summary>
		event IncomingCommandHandler OnConnectionlessCommand;

		/// <summary>
		/// Fired when a client connection sends its login data.
		/// </summary>
		event ConnectionAuthHandler OnConnectionAuth;

		/// <summary>
		/// Fired when a server has requested login information.
		/// </summary>
		event SendLoginHandler OnLoginRequested;

		/// <summary>
		/// Fired when a command has been recieved for an authorized connection.
		/// </summary>
		event IncomingCommandHandler OnCommandReceived;

		/// <summary>
		/// Fired when a connection to a remote host is established or lost.
		/// </summary>
		event ConnectionStateChangeHandler OnConnectionStateChanged;

		/// <summary>
		/// Fired when a server has accepted a client connection.
		/// </summary>
		event AuthenticatedHandler OnAuthFeedback;

		/// <summary>
		/// Fired when a connection request times out.
		/// </summary>
		event RequestTimedOutHandler OnConnectionRequestTimedOut;

		/// <summary>
		/// Gets the current state of the UDP server (idle, listening etc.)
		/// </summary>
		int State
		{
			get;
		}

		/// <summary>
		/// Gets or sets a value that determines whether or not new connections should be encrypted.
		/// </summary>
		bool Encrypt
		{
			get;
			set;
		}

		/// <summary>
		/// Starts listening on the given local IP address and port.
		/// </summary>
		/// <param name="IP">The local IP address to listen on (use an empty string to bind to all available).</param>
		/// <param name="Port">The port number to bind to.</param>
		/// <returns>UDP_OK on success, UDP_FAIL on failure.</returns>
		int StartListen(string IP, int Port);

		/// <summary>
		/// Stops the UDP server listening and drops all open connections.
		/// </summary>
		/// <returns>UDP_OK on success or UDP_FAIL if the UDP server is not listening.</returns>
		int StopListen();

		/// <summary>
		/// Sends a connectionless command to a remote host.
		/// </summary>
		/// <param name="IP">The IP address of the remote host.</param>
		/// <param name="Port">The remote port number.</param>
		/// <param name="opcode">The command opcode.</param>
		/// <param name="fields">The command data fields.</param>
		/// <returns>
		/// UDP_OK on success.
		/// UDP_RELIABLENODESTINATION when attempting to send a reliable packet.
		/// UDP_UNRELIABLETOOLONG if the packet data fields are too big.
		/// UDP_FAIL on general failure.
		/// </returns>
		int SendConnectionlessCommand(string IP, int Port, string opcode, string[] fields);

		/// <summary>
		/// Sends an unreliable command to a group of connections.
		/// </summary>
		/// <param name="filter">Filter flags to allow filtering in/out certain types of connections.</param>
		/// <param name="flags">The flags for the command.</param>
		/// <param name="opcode">The command opcode.</param>
		/// <param name="fields">The command data fields.</param>
		/// <returns>
		/// UDP_OK on success.
		/// UDP_RELIABLENODESTINATION when attempting to send a reliable packet.
		/// UDP_UNRELIABLETOOLONG if the packet data fields are too big.
		/// UDP_FAIL on general failure.
		/// </returns>
		int SendUnreliableCommandToAll(BroadcastFilter filter, byte flags, string opcode, string[] fields);

		/// <summary>
		/// Sends a reliable command to a group of connections.
		/// </summary>
		/// <param name="filter">Filter flags to allow filtering in/out certain types of connections.</param>
		/// <param name="flags">The flags for the command.</param>
		/// <param name="opcode">The command opcode.</param>
		/// <param name="fields">The command data fields.</param>
		/// <returns>
		/// UDP_OK on success.
		/// UDP_RELIABLEQUEUEFULL if the reliable queue is full.
		/// UDP_FAIL on general failure.
		/// </returns>
		int SendReliableCommandToAll(BroadcastFilter filter, byte flags, string opcode, string[] fields);

		/// <summary>
		/// Attempt to connect to a Genesis UDP server.
		/// </summary>
		/// <param name="RemoteIP">IP address or DNS hostname of the remote host. This string will be changed to an IP if a hostname is passed and resolved.</param>
		/// <param name="RemotePort">The port on the remote server.</param>
		/// <param name="request_id">This parameter is set to the generated request ID.</param>
		/// <returns>
		/// UDP_OK on success.
		/// UDP_UNABLETORESOLVE when a DNS hostname failed to resolve.
		/// UDP_ALREADYCONNECTED if a connection to the given host and port already exists.
		/// </returns>
		int RequestConnect(ref string RemoteIP, int RemotePort, out string request_id);

		/// <summary>
		/// Cancels a connection attempt to a remote host.
		/// </summary>
		/// <param name="RemoteIP">The IP address of the remote host that has a pending connection request.</param>
		/// <param name="RemotePort">The remote port.</param>
		/// <returns>UDP_OK</returns>
		int CancelConnect(string RemoteIP, int RemotePort);

		/// <summary>
		/// Cancels a connection attempt to a remote host.
		/// </summary>
		/// <param name="RequestID">The request ID of the connection attempt to be aborted.</param>
		/// <returns>UDP_OK</returns>
		int CancelConnect(string RequestID);

		/// <summary>
		/// Gets a reference to a connection given the remote hosts IP and port.
		/// </summary>
		/// <param name="RemoteIP">IP address of the remote host.</param>
		/// <param name="RemotePort">The port on the remote host.</param>
		/// <param name="conn">Set to the connection that is found, or set to null if not found.</param>
		/// <returns>
		/// UDP_OK on success.
		/// UDP_NOTFOUND when a matching connection is not found.
		/// </returns>
		int ConnectionByIPPort(string IP, int Port, out IConnection conn);

		/// <summary>
		/// Disconnects a connection to a remote host, optionally sendin a disconnect message and reason.
		/// </summary>
		/// <param name="conn">The connection interface to disconnect.</param>
		/// <param name="send_disconnect_packet">True if a disconnection packet should be sent to the remote host.</param>
		/// <param name="reason">If a disconnection packet is to be sent, this string will be sent as the reason for disconnection.</param>
		/// <returns>UDP_OK</returns>
		int RemoveConnection(IConnection conn, bool send_disconnect_packet, string reason);

		/// <summary>
		/// Returns an array of all connections of a specific type.
		/// </summary>
		/// <param name="servers">True if connection to servers should be returned, false to return conections to clients.</param>
		/// <param name="found">This parameter will be set to a reference of the array containing the found connections.</param>
		/// <returns>
		/// UDP_OK on success.
		/// UDP_NOTFOUND when a matching connection is not found.
		/// </returns>
		int GetConnections(bool servers, out IConnection[] found);

		/// <summary>
		/// Returns a string array of all the IP addresses available on the local machine.
		/// </summary>
		/// <returns>Array containing IP addresses.</returns>
		string[] GetLocalAddresses();
	}

	/// <summary>
	/// Allows instantiating internal classes within the Genesis asembly from external code.
	/// </summary>
	public class InterfaceFactory
	{
		/// <summary>
		/// Creates a new instance of the Genesis UDP socket controller.
		/// </summary>
		/// <param name="Name">Optional name for the object.</param>
		/// <returns>An instance of the Genesis UDP socket controller.</returns>
		public static IGenesisUDP CreateGenesisUDP(string Name)
		{
			return new GenesisUDP(Name);
		}
	}
}