/**
*	iloop.c	--	nsf subroutine
**/
#include	<stdio.h>
#include	<ctype.h>
#include	"nsf.h"

/**
*	mesg() -- message to user.
**/
void mesg(s)
char	*s;
{
	int	i;
	if (s != NULL) beep();
	if (s == NULL)
	s="Next Field: TAB     1st Field: HOME    Help: ESC     End: RETURN";
	move(LINES-1,0);
	clrtoeol();
	i = (COLS - strlen(s))/2;
	move(LINES-1,i);
	if (use_uline) attroff(A_UNDERLINE);
	addstr(s);
	if (use_uline) attron(A_UNDERLINE);
	move(fld[cfld].y,fld[cfld].x+ccol);
}
/**
*	backspace()
**/
void backspace(){
	struct	INFLD *p;
	int	y,x,c,i;
	p = &fld[cfld];
	y = p->y;
	x = p->x+ccol;
	if (ccol < 1){
		cfld--;
		if (cfld < 0) cfld = nfld - 1;
		ccol = 0;
		return;
	}
	if (ccol == (p->len - 1)){
		c = mvinch(y,x);
		if ((c & 0xff) != ' '){
			addch(' ');
			return;
		}
	}
	for(i = ccol ; i < fld[cfld].len ; ++i){
		x = fld[cfld].x + i;
		c = mvinch(y,x);
		mvaddch(y,x-1,c);
	}
	mvaddch(y,fld[cfld].x+fld[cfld].len-1,' ');
	ccol--;
}
/**
*	field_get()	get field value if it's ok.
**/
int field_get(){
	struct INFLD *p;
	int	i;
	char	buf[BUFSIZ],*s;
	p = &fld[cfld];
	for(i = 0 ; i < p->len ; i++){
		move (p->y,p->x + i);
		buf[i] = (char)inch();
	}
	for(i = p->len - 1; i >= 0 ; i--) if (buf[i] != ' ') break;
	buf[++i] = '\0';
	if (!(p->attr & SF_SELECT) && p->attr & (SF_DIGITS|SF_REAL)){
		s = &buf[0];
		while (*s == ' ') ++s;
		if (*s == '+' || *s == '-') ++s;
		while(*s >= '0' && *s <= '9') ++s;
		if (p->attr & SF_REAL){
			if (*s == '.') ++s;
			while (*s >= '0' && *s <= '9') ++s;
		}
		if (*s != '\0'){
			if (p->attr & SF_REAL) mesg("MUST BE NUMERIC");
			else mesg("MUST BE INTEGER NUMBER.");
			return 0;
		}
	}
	strcpy(p->inp,buf);
	return 1;
}
/**
*	end_ok()
**/
int end_ok(){
	ccol = 0;
	for(cfld = 0 ; cfld < nfld ; ++cfld){
		if (!field_get()) return 0;
		if ((fld[cfld].attr & SF_FORCE) && fld[cfld].inp[0] == '\0'){
			mesg("YOU CAN NOT OMIT THIS ITEM.");
			return 0;
		}
	}
	return 1;
}
/**
*	field_move()	move cfld and ccol
**/
void field_move(c)
int	c;
{
	int i,x,y,yy;

	if (c == KEY_HOME){
		cfld = ccol = 0;
		move(fld[0].y,fld[0].x);
		return;
	}
	x = fld[cfld].x + ccol;
	y = fld[cfld].y;
	if (c == KEY_DOWN || c == '\012'){
		for(i = (cfld + 1) % nfld;;i = (i+1)%nfld)
			if ((yy = fld[i].y) != y) break;
		for(i++;i < nfld && fld[i].y == yy;i++)
			if (fld[i].x > x) break;
		i--;
	}else if (c == KEY_UP){
		for(i = (cfld + nfld - 1) % nfld;;i = (i+nfld-1)%nfld)
			if ((yy = fld[i].y) != y) break;
		for(i--;i >= 0 && fld[i].y == yy;i--)
			if (fld[i].x+fld[i].len < x) break;
		i++;
	}else if (c == '\t'){
		i = cfld + 1;
		if (i >= nfld) i = 0;
	}else if (c == '\r'){
		for(i = cfld ; i < nfld ; ++i) if (fld[i].y > y) break;
	}
	if (i >= nfld || i < 0){
		beep();
		move(fld[cfld].y,fld[cfld].x+ccol);
		return;
	}
	cfld = i;
	ccol = 0;
	move(fld[cfld].y,fld[cfld].x+ccol);
}
/**
*	next_option()	display next option.
**/
void next_option(){
	struct INFLD *p;
	int	i;
	field_get();
	p = &fld[cfld];
	for(i = 0 ; i < p->len ; ++i) move(p->y,p->x+i),addch(' ');
	for(i = 0 ; i < p->nopt ; ++i) if (!strcmp(p->inp,p->opt[i])) break;
	if (++i >= p->nopt) i = 0;
	move(p->y,p->x);
	addstr(p->opt[i]);
	move(p->y,p->x);
}
void iloop(){
	int	i,c;
	char	buf[80];
	struct INFLD *p;
	if (cfld < 0) cfld = 0;
	if (cfld > nfld) cfld = nfld - 1;
	ccol = 0;
	if (use_uline) attron(A_UNDERLINE);
	for(i = 0 ; i < nfld ; ++i){
		p = &fld[i];
		move(p->y,p->x);
		addstr(p->def);
	}
	move(fld[cfld].y,fld[cfld].x);
	leaveok(stdscr,FALSE);
	if (initmesg[0] != '\0') mesg(initmesg);
	else mesg(NULL);
	while (1){
		move(fld[cfld].y,fld[cfld].x+ccol);
		refresh();
		c = getch();
		c &= 0x1ff;
		mesg(NULL);
		if (c == '\r'){
			if (!field_get()) continue;
			if (end_ok()) break;
		}else if (c == KEY_DOWN || c == KEY_UP || 
			c == KEY_HOME || c == '\t'|| c == '\012'){
			if (!field_get()) continue;
			field_move(c);
		}else if (c == KEY_LEFT){
			if (ccol > 0) ccol--;
			else{
				cfld--;
				if (cfld < 0) cfld = nfld - 1;
				ccol = fld[cfld].len - 1;
			}
		}else if (c == KEY_RIGHT){
			if (ccol < (fld[cfld].len - 1)) ccol++;
			else{
				cfld++;
				if (cfld >= nfld) cfld = 0;
				ccol = 0;
			}
		}else if (c == '\033'){	/* ESC */
			if (fld[cfld].help[0] == '\0') mesg(NULL);
			else	mesg(fld[cfld].help);
		}else if (fld[cfld].attr & SF_SELECT){
			if (c != ' ') mesg("HIT SPACE KEY TO CHANGE");
			else next_option();
		}else if (c == KEY_BACKSPACE || c == '\010'){
			backspace();
		}else if (c >= ' ' && c <= '}'){
			if (fld[cfld].attr & SF_UCASE) c = toupper(c);
			else if (fld[cfld].attr & SF_LCASE) c = tolower(c);
			addch(c);
			if ((ccol+1) >= fld[cfld].len){
				if (!field_get()) continue;
				if (fld[cfld].attr & SF_ASCEND)
					field_move('\t');
			}else{
				ccol++;
			}
		}else if (c == '\014'){
			clearok(stdscr,TRUE);
		}else{
			beep();
			if (debug_on){
				sprintf(buf,"0x%x (\\%o) comes",c,c);
				mesg(buf);
			}
		}
	}
}