/* -*-  Mode:C++; c-basic-offset:8; tab-width:8; indent-tabs-mode:t -*- */
/*
 * Copyright (c) 2001 University of Mannheim, Praktische Informatik IV
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Praktische Informatik IV,
 *      University of Mannheim and ACIRI.
 * 4. Neither the name of the University of Mannheim nor of ACIRI
 *    may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY U. MANNHEIM AND CONTRIBUTORS ``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 U. MANNHEIM OR CONTRIBUTORS 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.
 */

#include "agent.h"
#include "packet.h"
#include "ip.h"
#include "random.h"
#include "tfmcc.h"

#define LARGE_DOUBLE 9999999999.99 
#define SAMLLFLOAT 0.0000001

/* packet status */
#define UNKNOWN 0
#define RCVD 1
#define LOST 2
#define NOLOSS 3

#define DEFAULT_NUMSAMPLES 8 
#define MAX_NUM_RECVS 10000

class TfmccSinkAgent : public Agent {
public:
	TfmccSinkAgent();
	void recv(Packet*, Handler*);
	int command(int argc, const char*const* argv);
	void stop();

protected:
	void sendpkt();
	void nextpkt();
	void increase_pvec(int);
	void add_packet_to_history(Packet *);
	double adjust_history(double);
	double est_loss();
	double est_thput(); 
	void shift_array(int *a, int sz, int defval) ;
	void shift_array(double *a, int sz, double defval) ;
	void multiply_array(double *a, int sz, double multiplier);
	void print_loss(int sample, double ave_interval);
	double weighted_average(int start, int end, double factor, double *m, double *w, int *sample);
	double feedback_time(double rtt, int num_recv);

	int psize_;		// size of received packet
	int fairsize_;          // packet size of competing flow
	int avgsize_;           // avg size of sent packets (EWMA)
	int sum_psize_;
	int sum_lsize_;
	int aggregate_packets_; // bool
	int aggregate_loss_;    // bool
	double rtt_;		// smoothed measured rtt
	double rtt_est; 	// use adjusted one-way delay to continue to modify the rtt
	double rtt_lossinit;    // RTT when history was initialized
	double max_rtt;         // max RTT (from sender)
        double conservative_rtt;
	double one_way_;        // one-way delay from receiver to sender
	int smooth_;		// for the smoother method for incorporating
				//  incorporating new loss intervals

	// these assist in keep track of incming packets and calculate flost_
	double last_timestamp_, last_arrival_;
	int hsz;
	char *lossvec_;
	int  *sizevec_;
	double *rtvec_;
	double *tsvec_;
	int round_id ;
	int numsamples ;
	int *sample;
	double *weights ;
	double *mult ;
	double mult_factor_;	// most recent multiple of mult array
	int sample_count ;
	int last_sample ;  
	int maxseq; 		// max seq number seen
	int total_received_;	// total # of pkts rcvd by rcvr
	int bval_;		// value of B used in the formula
	double last_report_sent; 	// when was last feedback sent
	int rcvd_since_last_report; 	// # of packets rcvd since last report
	double lastloss; 	// when last loss occured
	int printStatus_;	// to print estimated loss rates
	int tight_loop_;	// flag for tight feedback loop to rep recv
	double fbtime_mult_;         // T = mult * RTT
	double fb_time;         // delay for feedback suppression
	double constant_rate_;  // set to positive value to use instead of calculated rate (Bit/s)
	double comparison_rate; // rate at beginning of feedback round (for suppression)
	double suppression_rate; // sender's suppression rate
	int receiver_leave;     // flag to indicate that CLR will leave group

	// these are for "faking" history after slow start
	int loss_seen_yet; 	// have we seen the first loss yet?
	int adjust_history_after_ss; // fake history after slow start? (0/1)
	int false_sample; 	// by how much?

	int discount ;		// emphasize most recent loss interval
				//  when it is very large
	int representative;     // flag: 1 = feedback receiver
	int recv_id;
	//int ca_; //Enable Sqrt(RTT) based congestion avoidance mode
	double df_;		// decay factor for accurate RTT estimate
        double rate_;
        int active_;
};