/*
 * "$Id: pqistreamer.cc,v 1.19 2007-02-18 21:46:50 rmf24 Exp $"
 *
 * 3P/PQI network interface for RetroShare.
 *
 * Copyright 2004-2006 by Robert Fernie.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Library General Public
 * License Version 2 as published by the Free Software Foundation.
 *
 * This library 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
 * Library General Public License for more details.
 *
 * You should have received a copy of the GNU Library General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA.
 *
 * Please report all bugs and problems to "retroshare@lunamutt.com".
 *
 */


#include <iostream>
#include <fstream>
#include <sstream>
#include "util/rsdebug.h"

#include "pqi/pqistreamer.h"
#include "pqi/pqinotify.h"

#include "serialiser/rsserial.h" 
#include "serialiser/rsbaseitems.h"  /***** For RsFileData *****/


const int pqistreamerzone = 8221;

const int PQISTREAM_ABS_MAX = 100000000; /* 100 MB/sec (actually per loop) */

/* This removes the print statements (which hammer pqidebug) */
/***
#define RSITEM_DEBUG 1
 ***/


pqistreamer::pqistreamer(RsSerialiser *rss, std::string id, BinInterface *bio_in, int bio_flags_in)
	:PQInterface(id), rsSerialiser(rss), bio(bio_in), bio_flags(bio_flags_in), 
	pkt_wpending(NULL), 
	totalRead(0), totalSent(0),
	currRead(0), currSent(0),
	avgReadCount(0), avgSentCount(0)
{
	avgLastUpdate = currReadTS = currSentTS = time(NULL);

	/* allocated once */
	pkt_rpend_size = getRsPktMaxSize();
	pkt_rpending = malloc(pkt_rpend_size);

	// 100 B/s (minimal)
	setMaxRate(true, 0.1);
	setMaxRate(false, 0.1);
	setRate(true, 0);
	setRate(false, 0);

        {
	  std::ostringstream out;
	  out << "pqistreamer::pqistreamer()";
          out << " Initialisation!" << std::endl;
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}

	if (!bio_in)
        {
	  std::ostringstream out;
	  out << "pqistreamer::pqistreamer()";
          out << " NULL bio, FATAL ERROR!" << std::endl;
	  pqioutput(PQL_ALERT, pqistreamerzone, out.str());
	  exit(1);
	}

	return;
}

pqistreamer::~pqistreamer()
{
        {
	  std::ostringstream out;
	  out << "pqistreamer::~pqistreamer()";
          out << " Destruction!" << std::endl;
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}

	if (bio_flags & BIN_FLAGS_NO_CLOSE)
	{
	  std::ostringstream out;
	  out << "pqistreamer::~pqistreamer()";
          out << " Not Closing BinInterface!" << std::endl;
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}
	else if (bio)
	{
	  std::ostringstream out;
	  out << "pqistreamer::~pqistreamer()";
          out << " Deleting BinInterface!" << std::endl;
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());

	  delete bio;
	}

	/* clean up serialiser */
	if (rsSerialiser)
		delete rsSerialiser;

	// clean up outgoing. (cntrl packets)
	while(out_pkt.size() > 0)
	{
		void *pkt = out_pkt.front();
		out_pkt.pop_front();
		free(pkt);
	}

	// clean up outgoing (data packets)
	while(out_data.size() > 0)
	{
		void *pkt = out_data.front();
		out_data.pop_front();
		free(pkt);
	}

	if (pkt_wpending)
	{
		free(pkt_wpending);
		pkt_wpending = NULL;
	}

	free(pkt_rpending);

	// clean up outgoing.
	while(incoming.size() > 0)
	{
		RsItem *i = incoming.front();
		incoming.pop_front();
		delete i;
	}
	return;
}


// Get/Send Items.
int	pqistreamer::SendItem(RsItem *si)
{
#ifdef RSITEM_DEBUG 
        {
	  std::ostringstream out;
	  out << "pqistreamer::SendItem():" << std::endl;
	  si -> print(out);
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}
#endif

	return queue_outpqi(si);
}

RsItem *pqistreamer::GetItem()
{
        {
	  std::ostringstream out;
	  out << "pqistreamer::GetItem()";
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}

	std::list<RsItem *>::iterator it;

	it = incoming.begin();
	if (it == incoming.end()) { return NULL; }

	RsItem *osr = (*it);
	incoming.erase(it);
	return osr;
}

// // PQInterface
int	pqistreamer::tick()
{
        {
	  std::ostringstream out;
	  out << "pqistreamer::tick()";
	  out << std::endl;
	  out << PeerId() << ": currRead/Sent: " << currRead << "/" << currSent;
	  out << std::endl;

	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}

	bio->tick();

	/* short circuit everything is bio isn't active */
	if (!(bio->isactive()))
	{
		return 0;
	}


	/* must do both, as outgoing will catch some bad sockets, 
	 * that incoming will not 
	 */

	handleincoming();
	handleoutgoing();

	/* give details of the packets */
	{
        	std::list<void *>::iterator it;

		std::ostringstream out;
		out << "pqistreamer::tick() Queued Data:";
	    	out << " for " << PeerId();

		if (bio->isactive())
		{
			out << " (active)";
		}
		else
		{
			out << " (waiting)";
		}
		out << std::endl;

		int total = 0;
		for(it = out_pkt.begin(); it != out_pkt.end(); it++)
		{
			total += getRsItemSize(*it);
		}

		out << "\t Out Packets [" << out_pkt.size() << "] => " << total;
		out << " bytes" << std::endl;

		total = 0;
		for(it = out_data.begin(); it != out_data.end(); it++)
		{
			total += getRsItemSize(*it);
		}

		out << "\t Out Data    [" << out_data.size() << "] => " << total;
		out << " bytes" << std::endl;

		out << "\t Incoming    [" << incoming.size() << "]";
		out << std::endl;

	  	pqioutput(PQL_DEBUG_BASIC, pqistreamerzone, out.str());
	}

	/* if there is more stuff in the queues */
	if ((incoming.size() > 0) || (out_pkt.size() > 0) || (out_data.size() > 0))
	{
		return 1;
	}
	return 0;
}

int	pqistreamer::status()
{
        {
	  std::ostringstream out;
	  out << "pqistreamer::status()";
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}

	if (bio->isactive())
	{
		std::ostringstream out;
		out << "Data in:" << totalRead << " out:" << totalSent;
	  	pqioutput(PQL_DEBUG_BASIC, pqistreamerzone, out.str());
	}

	return 0;
}

//
/**************** HANDLE OUTGOING TRANSLATION + TRANSMISSION ******/

int	pqistreamer::queue_outpqi(RsItem *pqi)
{
        {
	  std::ostringstream out;
	  out << "pqistreamer::queue_outpqi()";
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}

	/* decide which type of packet it is */
	RsFileData *dta = dynamic_cast<RsFileData *>(pqi);
	bool isCntrl = (dta == NULL);


        uint32_t pktsize = rsSerialiser->size(pqi);
	void *ptr = malloc(pktsize);
	if (rsSerialiser->serialise(pqi, ptr, &pktsize))
	{
		if (isCntrl)
		{
			out_pkt.push_back(ptr);
		}
		else
		{
			out_data.push_back(ptr);
		}
		if (!(bio_flags & BIN_FLAGS_NO_DELETE))
		{
			delete pqi;
		}
		return 1;
	}
	else
	{
		/* cleanup serialiser */
		free(ptr);
	}

	std::ostringstream out;
	out << "pqistreamer::queue_outpqi() Null Pkt generated!";
	out << std::endl;
	out << "Caused By: " << std::endl;
	pqi -> print(out);
	pqioutput(PQL_ALERT, pqistreamerzone, out.str());

	if (!(bio_flags & BIN_FLAGS_NO_DELETE))
	{
		delete pqi;
	}
	return 1; // keep error internal.
}

int 	pqistreamer::handleincomingitem(RsItem *pqi)
{
        {
	  std::ostringstream out;
	  out << "pqistreamer::handleincomingitem()";
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}

	// Use overloaded Contact function 
	pqi -> PeerId(PeerId());
	incoming.push_back(pqi);
	return 1;
}

int	pqistreamer::handleoutgoing()
{
        {
	  std::ostringstream out;
	  out << "pqistreamer::handleoutgoing()";
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}

	int maxbytes = outAllowedBytes();
	int sentbytes = 0;
	int len;
	int ss;

	std::list<void *>::iterator it;

	// if not connection, or cannot send anything... pause.
	if (!(bio->isactive()))
	{
		/* if we are not active - clear anything in the queues. */
		for(it = out_pkt.begin(); it != out_pkt.end(); )
		{
			free(*it);
			it = out_pkt.erase(it);

			std::ostringstream out;
			out << "pqistreamer::handleoutgoing() Not active -> Clearing Pkt!";
	  		pqioutput(PQL_DEBUG_BASIC, pqistreamerzone, out.str());
		}
		for(it = out_data.begin(); it != out_data.end(); )
		{
			free(*it);
			it = out_data.erase(it);

			std::ostringstream out;
			out << "pqistreamer::handleoutgoing() Not active -> Clearing DPkt!";
	  		pqioutput(PQL_DEBUG_BASIC, pqistreamerzone, out.str());
		}

		/* also remove the pending packets */
		if (pkt_wpending)
		{
			free(pkt_wpending);
			pkt_wpending = NULL;
		}

		outSentBytes(sentbytes);
		return 0;
	}
	
	// a very simple round robin

	bool sent = true;
	while(sent) // catch if all items sent.
	{
		sent = false;

		if ((!(bio->cansend())) || (maxbytes < sentbytes))
		{
			outSentBytes(sentbytes);
			return 0;
		}

		// send a out_pkt., else send out_data. unless
		// there is a pending packet.
		if (!pkt_wpending)
		{
			if (out_pkt.size() > 0)
			{
				pkt_wpending = *(out_pkt.begin()); 
				out_pkt.pop_front();
			}
			else if (out_data.size() > 0)
			{
				pkt_wpending = *(out_data.begin()); 
				out_data.pop_front();
			}
		}

		if (pkt_wpending)
		{
			std::ostringstream out;
			out << "Sending Out Pkt!";
			// write packet.
			len = getRsItemSize(pkt_wpending);
			if (len != (ss = bio->senddata(pkt_wpending, len)))
			{
				out << "Problems with Send Data!";
				out << std::endl;
	  			pqioutput(PQL_DEBUG_BASIC, pqistreamerzone, out.str());

				outSentBytes(sentbytes);
				// pkt_wpending will keep til next time.
				// ensuring exactly the same data is written (openSSL requirement).
				return -1;
			}

			out << " Success!" << std::endl;
	  		pqioutput(PQL_DEBUG_BASIC, pqistreamerzone, out.str());

			free(pkt_wpending);
			pkt_wpending = NULL;

			sentbytes += len;
			sent = true;
		}
	}
	outSentBytes(sentbytes);
	return 1;
}


/* Handles reading from input stream.
 */

int	pqistreamer::handleincoming()
{
	int readbytes = 0;

        {
	  std::ostringstream out;
	  out << "pqistreamer::handleincoming()";
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}

	if (!(bio->isactive()))
	{
		inReadBytes(readbytes);
		return 0;
	}

	// enough space to read any packet.
	int maxlen = pkt_rpend_size; 
	void *block = pkt_rpending; 

	// initial read size: basic packet.
	int blen = getRsPktBaseSize();

	int tmplen;
	uint32_t pktlen;
	int maxin = inAllowedBytes();

	while((maxin > readbytes) && (bio->moretoread()))
	{
		// read the basic block (minimum packet size)
		if (blen != (tmplen = bio->readdata(block, blen)))
		{
	  		pqioutput(PQL_DEBUG_BASIC, pqistreamerzone, 
				"pqistreamer::handleincoming() Didn't read BasePkt!");

			// error.... (either blocked or failure)
			inReadBytes(readbytes);
			if (tmplen == 0)
			{

				// most likely blocked!
	  			pqioutput(PQL_DEBUG_BASIC, pqistreamerzone, 
					"pqistreamer::handleincoming() read blocked");

				return 0;
			}
			else if (tmplen < 0)
			{
				// assume the worse, that 
				// the stream is bust ... and jump away.
	  			pqioutput(PQL_WARNING, pqistreamerzone, 
					"pqistreamer::handleincoming() Error in bio read");
				return -1;
			}
			else // tmplen > 0
			{
				// strange case....
				std::ostringstream out;
				out << "pqistreamer::handleincoming() Incomplete ";
				out << "(Strange) read of " << tmplen << " bytes";
	  			pqioutput(PQL_ALERT, pqistreamerzone, out.str());
				return -1;
			}
		}
		readbytes += tmplen;
		pktlen = tmplen;

		// workout how much more to read.
		int extralen = getRsItemSize(block) - blen;
		if (extralen > maxlen - blen)
		{
	  		pqioutput(PQL_ALERT, pqistreamerzone, "ERROR: Read Packet too Big!");

			pqiNotify *notify = getPqiNotify();
			if (notify)
			{
				std::string title =
					"Warning: Bad Packet Read";
			
	  			std::ostringstream msgout;
				msgout <<  "               **** WARNING ****     \n";
				msgout <<  "Retroshare has caught a BAD Packet Read";
				msgout <<  "\n";
				msgout <<  "This is normally caused by connecting to an";
				msgout <<  " OLD version of Retroshare";
				msgout <<  "\n";
				msgout <<  "(M:" << maxlen << " B:" << blen << " E:" << extralen << ")\n";
				msgout <<  "\n";
				msgout <<  "\n";
				msgout <<  "Please get your friends to upgrade to the latest version";
				msgout <<  "\n";
				msgout <<  "\n";
				msgout <<  "If you are sure the error was not caused by an old version";
				msgout <<  "\n";
				msgout <<  "Please report the problem to Retroshare's developers";
				msgout <<  "\n";

				std::string msg = msgout.str();
				notify->AddSysMessage(0, RS_SYS_WARNING, title, msg);
			}
			bio->close();	
			return -1;

			// Used to exit now! exit(1);
		}

		if (extralen > 0)
		{
			void *extradata = (void *) (((char *) block) + blen);

			if (extralen != (tmplen = bio->readdata(extradata, extralen)))
			{
				std::ostringstream out;
				out << "Error Completing Read (read ";
				out << tmplen << "/" << extralen << ")" << std::endl;
	  			pqioutput(PQL_ALERT, pqistreamerzone, out.str());

				pqiNotify *notify = getPqiNotify();
				if (notify)
				{
					std::string title =
						"Warning: Error Completing Read";
			
	  				std::ostringstream msgout;
					msgout <<  "               **** WARNING ****     \n";
					msgout <<  "Retroshare has experienced an unexpected Read ERROR";
					msgout <<  "\n";
					msgout <<  "(M:" << maxlen << " B:" << blen;
					msgout <<  " E:" << extralen << " R:" << tmplen << ")\n";
					msgout <<  "\n";
					msgout <<  "Please contact the developers.";
					msgout <<  "\n";

					std::string msg = msgout.str();
					notify->AddSysMessage(0, RS_SYS_WARNING, title, msg);
				}
				bio->close();	
				return -1;

				// if it is triggered ... need to modify code.
				// XXXX Bug to fix!
				//exit(1);

				// error....
				inReadBytes(readbytes);
				return -1;
			}

			readbytes += extralen;
			pktlen    += extralen;
		}


		// create packet, based on header.
		{
		  std::ostringstream out;
		  out << "Read Data Block -> Incoming Pkt(";
		  out << blen + extralen << ")" << std::endl;
		  pqioutput(PQL_DEBUG_BASIC, pqistreamerzone, out.str());
		}

		RsItem *pkt = rsSerialiser->deserialise(block, &pktlen);

		if ((pkt != NULL) && (0  < handleincomingitem(pkt)))
		{
	  		pqioutput(PQL_DEBUG_BASIC, pqistreamerzone, 
				"Successfully Read a Packet!");
		}
		else
		{
	  		pqioutput(PQL_ALERT, pqistreamerzone, 
				"Failed to handle Packet!");
			inReadBytes(readbytes);
			return -1;
		}
	}

	inReadBytes(readbytes);
	return 0;
}



/* BandWidth Management Assistance */

float   pqistreamer::outTimeSlice()
{
        {
	  std::ostringstream out;
	  out << "pqistreamer::outTimeSlice()";
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}

	//fixme("pqistreamer::outTimeSlice()", 1);
	return 1;
}

// very simple..... 
int     pqistreamer::outAllowedBytes()
{
	int t = time(NULL); // get current timestep.

	/* allow a lot if not bandwidthLimited */
	if (!bio->bandwidthLimited())
	{
		currSent = 0;
		currSentTS = t;
		return PQISTREAM_ABS_MAX;
	}

	int dt = t - currSentTS;
	// limiter -> for when currSentTs -> 0.
	if (dt > 5)
		dt = 5;

	int maxout = (int) (getMaxRate(false) * 1000.0);
	currSent -= dt * maxout;
	if (currSent < 0)
	{
		currSent = 0;
	}

	currSentTS = t;

        {
	  std::ostringstream out;
	  out << "pqistreamer::outAllowedBytes() is ";
	  out << maxout - currSent << "/";
	  out << maxout;
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}


	return maxout - currSent;
}

int     pqistreamer::inAllowedBytes()
{
	int t = time(NULL); // get current timestep.

	/* allow a lot if not bandwidthLimited */
	if (!bio->bandwidthLimited())
	{
		currReadTS = t;
		currRead = 0;
		return PQISTREAM_ABS_MAX;
	}

	int dt = t - currReadTS;
	// limiter -> for when currReadTs -> 0.
	if (dt > 5)
		dt = 5;

	int maxin = (int) (getMaxRate(true) * 1000.0);
	currRead -= dt * maxin;
	if (currRead < 0)
	{
		currRead = 0;
	}

	currReadTS = t;

        {
	  std::ostringstream out;
	  out << "pqistreamer::inAllowedBytes() is ";
	  out << maxin - currRead << "/";
	  out << maxin;
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}


	return maxin - currRead;
}


static const float AVG_PERIOD = 5; // sec
static const float AVG_FRAC = 0.8; // for low pass filter.

void    pqistreamer::outSentBytes(int outb)
{
        {
	  std::ostringstream out;
	  out << "pqistreamer::outSentBytes(): ";
	  out << outb << "@" << getRate(false) << "kB/s" << std::endl;
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}


	totalSent += outb;
	currSent += outb;
	avgSentCount += outb;

	int t = time(NULL); // get current timestep.
	if (t - avgLastUpdate > AVG_PERIOD)
	{
		float avgReadpSec = getRate(true);
		float avgSentpSec = getRate(false);

		avgReadpSec *= AVG_FRAC;
		avgReadpSec += (1.0 - AVG_FRAC) * avgReadCount / 
				(1000.0 * (t - avgLastUpdate));

		avgSentpSec *= AVG_FRAC;
		avgSentpSec += (1.0 - AVG_FRAC) * avgSentCount / 
				(1000.0 * (t - avgLastUpdate));

	
		/* pretend our rate is zero if we are 
		 * not bandwidthLimited().
		 */
		if (bio->bandwidthLimited())
		{
			setRate(true, avgReadpSec);
			setRate(false, avgSentpSec);
		}
		else
		{
			setRate(true, 0);
			setRate(false, 0);
		}


		avgLastUpdate = t;
		avgReadCount = 0;
		avgSentCount = 0;
	}
	return;
}

void    pqistreamer::inReadBytes(int inb)
{
        {
	  std::ostringstream out;
	  out << "pqistreamer::inReadBytes(): ";
	  out << inb << "@" << getRate(true) << "kB/s" << std::endl;
	  pqioutput(PQL_DEBUG_ALL, pqistreamerzone, out.str());
	}

	totalRead += inb;
	currRead += inb;
	avgReadCount += inb;

	return;
}