//-----------------------------------------------------------------
//	netchat.cpp
//
//	This Linux application implements PC-to-PC communication
//	via the '/dev/nic' device-file interface to functions in
//	our 'nicpoll.c' character-mode device-driver for Intel's
//	Pro1000 network controller on 'anchor' cluster stations. 
//	(You must link this program with the 'ncurses' library.) 
//
//	 compile using:  $ gcc netchat.cpp -lncurses -o netchat
//
//	programmer: ALLAN CRUSE
//	written on: 10 MAR 2008 
//-----------------------------------------------------------------

#include <curses.h>	// needed for initscr(), refresh(), etc
#include <unistd.h>	// needed for STDIN_FILENO
#include <fcntl.h>	// needed for open(), O_RDWR

#define KEY_LO 32
#define KEY_HI 126
#define KEY_LF 10
#define KEY_CR 13 
#define KEY_ESC 27
#define KEY_TAB 9
#define KEY_RUB 127
#define KEY_BLANK 32

int aux, kbd = STDIN_FILENO;		// file-descriptor numbers
char device_name[] = "/dev/nic";	// name of the device file


void writeto_window( WINDOW *win, int datum )
{
	switch ( datum )
	{
	case KEY_LF:
	case KEY_CR:	waddch( win, KEY_LF ); 
			waddch( win, KEY_CR ); break;  
	case KEY_TAB:	waddch( win,  KEY_TAB ); 
	case KEY_ESC:   break;
	case KEY_RUB:	int	row, col;
			getyx( win, row, col );
			if ( col > 0 ) --col;
			wmove( win, row, col );
			waddch( win, KEY_BLANK );
			wmove( win, row, col );
			break;
	default:  if (( datum < KEY_LO )||( datum > KEY_HI )) break;
		  else	waddch( win, datum ); break;
	}
	wrefresh( win );
}



WINDOW *subwindow( int rows, int cols, int top, int left )
{
	WINDOW	*win = subwin( stdscr, rows, cols, top, left );
	box( win, ACS_VLINE, ACS_HLINE );
	wrefresh( win );
	delwin( win );
	win = subwin( stdscr, rows-2, cols-2, top+1, left+1 );
	scrollok( win, TRUE );
	leaveok( win, FALSE );
	return	win;
}

int main( void )
{
	if ( ( aux = open( device_name, O_RDWR ) ) < 0 )
	{ printf( "cannot open \'%s\' \n", device_name ); return -1; }

	initscr();		// creates windows 'stdscr' and 'curscr' 
	WINDOW *rx_win = subwindow( 12, 80,  0, 0 );
	WINDOW *tx_win = subwindow( 12, 80, 12, 0 );
	raw();			// puts console keyboard into 'raw' mode
	noecho();		// and turns off echoing of console input 
	move( 13, 1 );		// places cursor at top corner of 'tx_win'
	refresh();		// updates actual screen to match 'stdscr'

	fd_set	permset;	
	FD_ZERO( &permset );			// initialize set to zeros
	FD_SET( kbd, &permset );		// listen to console input
	FD_SET( aux, &permset );		// listen to remote device
	int	ndev = 1 + aux;			// maximum fileno for poll

	while ( 1 ) 
	    	{
		int	row, col, inch = 0;
		fd_set	readset = permset;
		if ( select( ndev, &readset, NULL, NULL, NULL ) < 0 ) break;
		
		if ( FD_ISSET( kbd, &readset ) )  		
			if ( read( kbd, &inch, 1 ) > 0 )
				{	
				writeto_window( tx_win, inch );
				write( aux, &inch, 1 );
				if ( inch == KEY_ESC ) break;
				}

		if ( FD_ISSET( aux, &readset ) )
			if ( read( aux, &inch, 1 ) > 0 )
				writeto_window( rx_win, inch );  

		getyx( tx_win, row, col );
		move( row+13, col+1 );
		refresh();
		}
	endwin();
}