/*
Program: MENU.C
Author : Kim Moser
Date   : 15 August 1989
System : IBM PC / Borland Turbo-C 2.0
Descrip: Generic menu system

Usage  : MENU
*/

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <ctype.h>
#include <dir.h>
#include "kmvid.h"

char *NEXTNAME="E:\\NEXT.BAT";  /* Batch file to be executed next */
char *PNAME;
  /* Needed only because argv[0] isn't global, and must be copied to PNAME */

#define NORMFG WHITE
#define NORMBG BLACK

#define HIGHFG YELLOW
#define HIGHBG BLUE

int MAXCHOICE=0;  /* # of choices; determined at runtime */

#define STARTROW 6
/* Row at which to start writing menu choices */

char ERR[255];  /* Error msgs are written to this string via sprintf() */
char CURDRIVE;  /* Letter of current drive; set at runtime */

struct {
	scrncoord x, y;  /* 'y' is just an offset from STARTROW */
	char name[80];
	char descrip[80];
	char batch[80];
} MENU[] = {
	0,0, " RepTools Demo ", "Demonstration of RepTools (Modula-2 utility library for programmers)",
	  "A:\nCD\\TOOLDEMO\nTOOLDEMO",
	0,1, " RepTools documentation and demo source ", "Documentation for RepTools, and Modula-2 source code for demo",
	  "A:\\UTIL\\L A:\\TOOLDEMO\\REPTOOLS.DOC A:\\TOOLDEMO\\TOOLDEMO.MOD",
	0,3, " Slide Show ", "Slide show demonstration (requires EGA)",
	  "A:\nCD\\SLIDE\nSS",
	0,5, " Life ", "John Conway's game of Life",
	  "A:\nCD\\LIFE\nLIFE",
	0,6, " Life documentation and source ", "Documentation and C source code for Life",
	  "A:\\UTIL\\L A:\\LIFE\\LIFE.DOC A:\\LIFE\\LIFE.C",
	0,8, " ViewC64 Demo ", "Demonstration of ViewC64 (view C-64 graphics on a PC; requires EGA)",
	  "A:\nCD\\VIEWC64\nVIEWDEMO.BAT",
	0,9, " ViewC64 documentation ", "Documentation for ViewC64",
	  "A:\\UTIL\\L A:\\VIEWC64\\VIEWC64.DOC",
	0,0, "", "", ""
};

void halt(s)
char *s;
{
	fprintf(stderr,s);
	fprintf(stderr, "\nNote: the DOS environment variable COMSPEC must be set to the\n" );
	fprintf(stderr, "fully qualified filename (including drive and path) of COMMAND.COM\n" );
	exit(1);
}

void hilite( n )
int n;
{
	set_color( HIGHFG, HIGHBG );
	writeat( MENU[n].x, MENU[n].y, MENU[n].name );
	set_color( NORMFG, NORMBG );
	writeat( MENU[n].x-1, MENU[n].y, "\020" );
	writeat( MENU[n].x+strlen(MENU[n].name), MENU[n].y, "\021" );

	set_color( GREEN, BLACK );
	writeatcenter( 18, "                                                                            " );
	writeatcenter( 18, MENU[n].descrip );
}

void unhilite( n )
int n;
{
	set_color( NORMFG, NORMBG );
	writeat( MENU[n].x, MENU[n].y, MENU[n].name );
	writeat( MENU[n].x-1, MENU[n].y, " " );
	writeat( MENU[n].x+strlen(MENU[n].name), MENU[n].y, " " );

}

void run(n)
int n;  /* Choice (0=first, etc.) */
{
	char s[255];  /* Temp */
	int i=0, j=0;  /* Indexes into MENU[n].batch and s, respectively */

	while(MENU[n].batch[i]) {
		for (j=0; (MENU[n].batch[i]!='\n') && MENU[n].batch[i]; j++) {
			s[j]=MENU[n].batch[i];
			i++;
		}
		s[j]='\n';
		s[j+1]=0;  /* Terminate string */
		i++;

		if ( system(s) ) {
			sprintf( ERR, "Unable to perform command:\n%s", s );
			halt(ERR);
		}
	}

/*
	FILE *f;

	if ((f=fopen(NEXTNAME, "w")) == NULL) {
		fclose(f);
		sprintf( ERR, "%s: Error creating '%s'\n", PNAME, NEXTNAME );
		halt(err);
	}

	fprintf( f, MENU[n].batch );
	/* If we're making a blank batch file... */
	if (n != MAXCHOICE) {
		/* ...put line in batch file to restart */
		fprintf( f, "\nA:\\DEMO" );
	}

	if (fclose(f)) {
		fprintf( stderr, "%s: Error closing '%s'\n", PNAME, NEXTNAME );
		exit(1);
	}
*/
}

void draw(n)
int n;  /* Which choice should start hilighted */
{
	int i;

	clearscr(WHITE, BLACK);
	set_color(LIGHTGRAY, BLACK);
	box( 1, 4, 80, 17, SINGLEBOX );
	box( 1, 17, 80, 19, SINGLEBOX );
	writeatch(1, 17, '\xC3');
	writeatch(80, 17, '\xB4');

	set_color(CYAN,BLACK);
	writeatcenter(21, "For more information on these programs, please contact:" );
	set_color(LIGHTCYAN, BLACK);
	writeatcenter(22, "Kim Moser");
	writeatcenter(23, "127 East 15th Street" );
	writeatcenter(24, "New York, NY 10003" );
	writeatcenter(25, "(212) 674-7205" );

	set_color(LIGHTBLUE, BLACK);
	writeatcenter( 1, "Use the \030 \031 \032 \033 keys to highlight an item from the menu below," );
	writeatcenter( 2, "then press the <ENTER> key to select the highlighted item." );
	writeatcenter( 3, "Press 'Q' or <ESC> to quit." );

	for (i=0; i<MAXCHOICE; i++)
		unhilite(i);

	hilite(n);
}

void main(argc, argv)
int argc;
char **argv;
{
	boolean done=FALSE,update=TRUE,redraw=TRUE;
	int old, j, i;  /* Which choice is displayed */

	PNAME=argv[0];
	initkmvid();

	CURDRIVE=getdisk()+'A';

	/* Count number of choices, center them, add STARTROW to 'y',
	   and change 'A:' to current drive: */
	for (i=0; MENU[i].name[0]; i++) {
		MAXCHOICE++;
		MENU[i].x = (vidcol()-strlen(MENU[i].name))/2;
		MENU[i].y += STARTROW;
		for (j=0; MENU[i].batch[j]; j++) {
			if ( (toupper(MENU[i].batch[j])=='A') && (MENU[i].batch[j+1]==':') ) {
				MENU[i].batch[j]=CURDRIVE;
			}
		}
	}

	i=0;
	do {
		if (redraw) {
			draw(i);
			redraw=FALSE;
		}

		old = i;
		update = TRUE;
		switch (keyhit()) {
			case LEFTKEY:
			case UPKEY:
				if (i)
					i--;
				else
					i=MAXCHOICE-1;
				break;
			case RIGHTKEY:
			case DOWNKEY:
				if (i<MAXCHOICE-1)
					i++;
				else
					i=0;
				break;
			case HOMEKEY:
				i=0;
				break;
			case ENDKEY:
				i=MAXCHOICE-1;
				break;
			case ENTERKEY:
				update = FALSE;
				clearscr(WHITE, BLACK);
				writeatcenter( 11, "Please wait..." );
				run(i);  /* Run selected file */
				redraw=TRUE;
				break;
			case ESCKEY:
			case 'q':
			case 'Q':
				done=TRUE;
				update=FALSE;
				break;
			default:
				update = FALSE;
				break;
		}
		if (update) {
			hilite(i);
			unhilite(old);
		}
	} while (!done);

	clearscr(WHITE,BLACK);
	exit(0);
}