/*	pingclient.c	- a client program that uses the socket interface to tcp */


#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/times.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/wait.h> 
#include <netdb.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#include "client.h"
#include "tcpblockio.h"
#include "timer.h"


#define TIMES  10	
#define STEPS   40
#define STARTPOINT 0
#define ENDPOINT 0.16
#define SET_RATE 1
#define RECORD_LOSS 2

char	data[1024];


int main( int argc, char **argv )
{
	int						amount=0;
	int						fd, nettemp;
	struct sockaddr_in		server_addr, client_addr;
	char					local_node[MAXHOSTNAMELEN];
	float startPoint;
	float endPoint, dropRate, rateDiff;
	int status, i, steps=40;
	pid_t pid;

	if ( argc != 6 )
	{
		fprintf(stderr, "usage: %s port# IPaddress startRate endRate Steps\n", 
				argv[ 0 ] );
		exit( 1 );
	}

	startPoint = atof( argv[3] );
	if (startPoint <= 0)
		startPoint = STARTPOINT;

	endPoint = atof( argv[4] );
	if (endPoint <=0 )
		endPoint = ENDPOINT;
	
	if ( endPoint < startPoint )
	{
		fprintf(stderr, "endpoint should not be less than startpoint\n");
		exit( 1 );
	}

	steps = atoi( argv[5] );
	if ( steps <= 0 )
	{
		steps = STEPS;
	}
	
	/*  get the internet name of the local host node on which we are running */
	if( gethostname(local_node, MAXHOSTNAMELEN) < 0 )
		{
		perror("pingclient gethostname");
		exit(EXIT_FAILURE);
		}
	fprintf(stderr, "myclient: on host %s\n", local_node);

	fd = openclient( 5678, "dublin.cs.unh.edu", &server_addr, &client_addr);

	/*	we are now successfully connected to a remote server */
	fprintf(stderr, "myclient: at internet address %s, port %d\n", 
				inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port));
	fprintf(stderr,
			"pingclient: sending to server at internet address %s, port %d\n",
					inet_ntoa(server_addr.sin_addr), 5678);

	rateDiff = ( endPoint - startPoint ) / steps;
	/* outer for loop set dropping rate */
	for ( dropRate=startPoint; dropRate <= endPoint; dropRate += rateDiff )
	{
		/* printf rate to a buffer */
		fprintf(stderr, "\nDublin packet drop rate is set to: %f\n\n", 
				dropRate );
		sprintf( data, "%d %.8f", SET_RATE, dropRate );

		/* Tell server the size of data */
		amount = strlen( data );
		nettemp = htonl( amount );
		if( writeblock(fd, (char *)&nettemp, sizeof(nettemp)) != sizeof(nettemp) )
			exit( EXIT_FAILURE );
		/* write amount bytes data */
		if ( writeblock( fd, data, amount ) < 0 )
			exit(EXIT_FAILURE);

		/* server will echo the message received after do what it should do */
		if( readblock(fd, data, amount) <= 0 )
			break;

		/* inner loop run blasttest for TIMES times */
		for( i = 0; i < TIMES; i++ )
		{
			/* fork a child to run blastclient */
			if( (pid = vfork()) < 0 )
				exit( EXIT_FAILURE );
			else if ( pid > 0 )	
			{
				/* parent process just waits for child to stop and restart */
				wait(&status);

				/* parent process tell server to record the packet loss */
				/* printf rate to a buffer */
				sprintf( data, "%d", RECORD_LOSS);

				/* Tell server the size of data */
				amount = strlen( data );
				nettemp = htonl( amount );
				if( writeblock(fd, (char *)&nettemp, sizeof(nettemp)) 
						!= sizeof(nettemp) )
					exit( EXIT_FAILURE );

				/* write amount bytes data */
				if ( writeblock( fd, data, amount ) < 0 )
					exit(EXIT_FAILURE);

				/* server will echo the message received after do 
				 * what it should do */
				if( readblock(fd, data, amount) <= 0 )
					exit(EXIT_FAILURE);
				continue;
			}else
			{
				/* child process execute blasttest */
			fprintf(stderr, "\n\nblastclient 1026 192.168.2.2 100000 1448\n" );
				execlp("blastclient","blastclient", "1026", "192.168.2.2", 
						"100000", "1448", NULL );
				exit( 0 );
			}
		}/* end of inner for loop */
	}/* end of outer for loop */

	return 0;
}/* end of main */