nc-readstr.c

/*
 *	ncurses read/edit string with utf8 support
 * 
 *	Copyright (C) 2017-2021 Nicholas Christopoulos.
 *
 *	This is free software: you can redistribute it and/or modify it under
 *	the terms of the GNU General Public License as published by the
 *	Free Software Foundation, either version 3 of the License, or (at your
 *	option) any later version.
 *
 *	It is distributed in the hope that it will be useful, but WITHOUT ANY
 *	WARRANTY; without even the implied warranty of MERCHANTABILITY or
 *	FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
 *	for more details.
 *
 *	You should have received a copy of the GNU General Public License
 *	along with it. If not, see <http://www.gnu.org/licenses/>.
 *
 * 	Written by Nicholas Christopoulos <nereus@freemail.gr>
 */

#include <wchar.h>
#include <stdlib.h>
#include "nc-plus.h"

//
bool nc_mvweditstr(WINDOW *w, int y, int x, char *u8str, int maxlen) {
	int		pos = 0, len, i, ocurs, key;
	bool	insert = true;
	wchar_t *str, *wcs, wch;
	char	*s;

	wcs = u8towcs(u8str);
	str = (wchar_t *) m_alloc(sizeof(wchar_t) * (maxlen + 1));
	wcscpy(str, wcs);
	m_free(wcs);
	len = wcslen(str);
	ocurs = curs_set(1);
	while ( true ) {
		// print
		
		s = wcstou8(str);
		if ( s ) {
			mvwprintw(w, y, x, "%s", s);
			m_free(s);
			}
		mvwhline (w, y, x + len, ' ', maxlen - len);
		
		// get key
		key = mvwgetch(w, y, x + pos);
		if ( u8ischar(key) ) {
			char mbs[7];
			int keylen = u8csize(key);
			mbs[0] = key;
			for ( i = 1; i < keylen; i ++ )
				mbs[i] = wgetch(w);
			mbs[keylen] = '\0';
			wch = u8towc(mbs);
			}
		else
			wch = (wchar_t) key;
		
		// execute
		switch ( key ) {
		case KEY_LEFT:	if ( pos ) pos --; break;
		case KEY_RIGHT:	if ( str[pos] ) pos ++; break;
		case '
':
		case KEY_HOME:	pos = 0; break;
		case '':
		case KEY_END:	pos = len; break;
		case '\010': case '\x7f':
		case KEY_BACKSPACE:
			if ( pos ) {
				pos --; len --;
				for ( i = pos; str[i]; i ++ )
					str[i] = str[i+1];
				str[len] = L'\0';
				}
			break;
		case KEY_DC:
			if ( str[pos] ) {
				for ( i = pos; str[i]; i ++ )
					str[i] = str[i+1];
				len --;
				}
			break;
		case KEY_IC:	
			insert = !insert;
			curs_set((insert)?1:2);
			break;
		case 27: case '': case '': case '':
		case KEY_CANCEL:
			curs_set(ocurs);
			m_free(str);
			return false; // canceled
		case '\r': case '\n':
		case KEY_ENTER: 
			mvwprintw(w, y, x, "%ls", str);
			mvwhline (w, y, x + len, ' ', maxlen - len);
			curs_set(ocurs);
			u8cpytostr(u8str, str);
			return true;
		default:
			if ( len < maxlen ) {
				if ( insert ) {
					for ( i = len; i >= pos; i -- )
						str[i+1] = str[i];
					str[pos] = wch;
					str[++ len] = L'\0';
					}
				else {
					str[pos] = key;
					if ( pos == len )
						str[++ len] = L'\0';
					}
				pos ++;
				}
			}
		}
	return false; // never comes here
	}

//
bool nc_mvwreadstr(WINDOW *w, int y, int x, char *str, int maxlen) {
	*str = '\0';
	return nc_mvweditstr(w, y, x, str, maxlen);
	}

/////
bool nc_mveditstr(int y, int x, char *s, int m)	{ return nc_mvweditstr(stdscr,y,x,s,m); }
bool nc_mvreadstr(int y, int x, char *s, int m)	{ return nc_mvwreadstr(stdscr,y,x,s,m); }
bool nc_editstr(char *s, int m)					{ return nc_mvweditstr(stdscr,getcury(stdscr),getcurx(stdscr),s,m); }
bool nc_readstr(char *s, int m)					{ return nc_mvwreadstr(stdscr,getcury(stdscr),getcurx(stdscr),s,m); }
bool nc_weditstr(WINDOW *w, char *s, int m)		{ return nc_mvweditstr(w,getcury(w),getcurx(w),s,m); }
bool nc_wreadstr(WINDOW *w, char *s, int m)		{ return nc_mvwreadstr(w,getcury(w),getcurx(w),s,m); }