// NeL - MMORPG Framework <http://dev.ryzom.com/projects/nel/>
// Copyright (C) 2010  Winch Gate Property Limited
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 of the
// License, or (at your option) any later version.
//
// This program 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.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.


/*
 * Layer 3 and Service example, ping server.
 *
 * This ping service expects pings, sends pongs back.
 *
 * To run this program, ensure there is a file "ping_service.cfg"
 * containing the location of the naming service (NSHost, NSPort)
 * in the working directory. The naming service must be running.
 */


// We're building a server, using the NeL Service framework
#include "nel/net/service.h"
using namespace NLNET;
using namespace NLMISC;
using namespace std;

// Must be a pointer to control when to start listening socket and when stop it
CCallbackServer *Server;
vector<TSockId> Clients;

// MESSAGES

// ***************************************************************************
void clientWantsToConnect ( TSockId from, void *arg )
{
	// Called when a client wants to connect
	Clients.push_back (from);
}

// ***************************************************************************
void clientWantsToDisconnect ( TSockId from, void *arg )
{
	// Called when a client wants to disconnect
	for (uint i = 0; i < Clients.size(); ++i)
		if (Clients[i] == from)
		{
			Clients.erase(Clients.begin()+i);
			return;
		}
}

/*
 * Callback function called when receiving a "PING" message
 *
 * Arguments:
 * - msgin:	the incoming message (coming from a client)
 * - from: the "sockid" of the sender client
 * - server: the CCallbackNetBase object (which really is a CCallbackServer object, for a server)
 *
 * Input (expected message from a client): PING
 * - uint32: ping counter
 *
 * Output (sent message to the ping server): PONG
 * - uint32: ping counter
 */
void cbPing( CMessage& msgin, TSockId from, CCallbackNetBase& server )
{
	uint32 counter;

	// Input
	msgin.serial( counter );

	// Output
	CMessage msgout( "PONG" );
	msgout.serial( counter );
	server.send( msgout, from );

	nlinfo( "PING -> PONG" );
}


/*
 * Callback array for messages received from a client
 */
TCallbackItem CallbackArray[] =
{
	{ "PING", cbPing }
};


// SERVICE

// ***************************************************************************
class CPingService : public IService
{
public:

	void init ()
	{
		// Init the server on port 3333
		Server = new CCallbackServer();
		Server->init (3333);
		Server->setConnectionCallback (clientWantsToConnect, NULL);
		Server->setDisconnectionCallback (clientWantsToDisconnect, NULL);
		Server->addCallbackArray (CallbackArray, 1);
	}

	bool update ()
	{
		// this function is called every "loop". you return true if you want
		// to continue or return false if you want to exit the service.
		// the loop is called evenly (by default, at least one time per second).

		Server->update();

		return true;
	}

	void release ()
	{
		// Must delete the server here
		delete Server;
	}
};

/*
 * Declare a service with the class IService, the names "PS" (short) and "ping_service" (long).
 * The port is automatically allocated (0) and the main callback array is CallbackArray.
 */
NLNET_SERVICE_MAIN( CPingService, "PS", "ping_service", 0, EmptyCallbackArray, "", "" )