/***************************************************************
 *
 *	hotpotato.c
 *
 *	The hotpotato cnet example from section 6
 *	of "Getting Started With cnet," Jeff Ondich, 2000.
 *
 ***************************************************************/

#include	<cnet.h>
#include	<time.h>
#include	<stdlib.h>
#include	"hotpotato.h"

/* Global variables. */

int		frameNumber = 0;


/* Event handler implementations. */

void reboot_node( CnetEvent event, CnetTimer timer, CnetData data )
{
	CNET_set_handler( EV_APPLICATIONREADY,  on_app_ready, 0 );
	CNET_set_handler( EV_PHYSICALREADY,  on_phys_ready, 0 );
	
	if( nodeinfo.nodenumber == 0 )
		CNET_enable_application( ALLNODES );
	
	(void)srand( (int)time(NULL) );
}


void on_app_ready( CnetEvent event, CnetTimer timer, CnetData data )
{
	int		link;
	int		length = MAX_MESSAGE_SIZE;
	Frame	f;
	
	/* Get the message and disable the application layer. */

	CHECK( CNET_read_application( &(f.destination), f.data, &length ) );
	CHECK( CNET_disable_application( ALLNODES ) );


	/* Send the message on its way. */

	f.hops = 0;
	f.source = nodeinfo.address;
	f.frameID = ++frameNumber;
	length += FRAME_HEADER_SIZE;
	link = ((int)rand() % nodeinfo.nlinks) + 1;
	CHECK( CNET_write_physical_reliable( link, (char *)(&f), &length ) );
	
	printf( "Originating frame #%d from %s bound for %ld\n",
				f.frameID, nodeinfo.nodename, f.destination );
}


void on_phys_ready( CnetEvent ev, CnetTimer timer, CnetData data )
{
	int			link;
	int			length = MAX_MESSAGE_SIZE + FRAME_HEADER_SIZE;
	Frame		f;
	
	CHECK( CNET_read_physical( &link, (char *)(&f), &length ) );
	f.hops++;
	
	if( f.destination == nodeinfo.address )
	{
		length -= FRAME_HEADER_SIZE;
		CHECK( CNET_write_application( f.data, &length ) );
		printf( "Delivering frame #%d to %s after %d hops\n",
						f.frameID, nodeinfo.nodename, f.hops );
	}
	else
	{
		link = (rand() % nodeinfo.nlinks) + 1;
		CHECK( CNET_write_physical_reliable( link, (char *)(&f), &length ) );

		printf( "\tFrame #%d passing through %s on %dth hop\n",
						f.frameID, nodeinfo.nodename, f.hops );
	}
}