1 /*
2  *  menubox.c -- implements the menu box
3  *
4  *  ORIGINAL AUTHOR: Savio Lam (lam836@cs.cuhk.hk)
5  *  MODIFIED FOR LINUX KERNEL CONFIG BY: William Roadcap (roadcapw@cfw.com)
6  *
7  *  This program is free software; you can redistribute it and/or
8  *  modify it under the terms of the GNU General Public License
9  *  as published by the Free Software Foundation; either version 2
10  *  of the License, or (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, write to the Free Software
19  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
20  */
21 
22 /*
23  *  Changes by Clifford Wolf (god@clifford.at)
24  *
25  *  [ 1998-06-13 ]
26  *
27  *    *)  A bugfix for the Page-Down problem
28  *
29  *    *)  Formerly when I used Page Down and Page Up, the cursor would be set
30  *        to the first position in the menu box.  Now lxdialog is a bit
31  *        smarter and works more like other menu systems (just have a look at
32  *        it).
33  *
34  *    *)  Formerly if I selected something my scrolling would be broken because
35  *        lxdialog is re-invoked by the Menuconfig shell script, can't
36  *        remember the last scrolling position, and just sets it so that the
37  *        cursor is at the bottom of the box.  Now it writes the temporary file
38  *        lxdialog.scrltmp which contains this information. The file is
39  *        deleted by lxdialog if the user leaves a submenu or enters a new
40  *        one, but it would be nice if Menuconfig could make another "rm -f"
41  *        just to be sure.  Just try it out - you will recognise a difference!
42  *
43  *  [ 1998-06-14 ]
44  *
45  *    *)  Now lxdialog is crash-safe against broken "lxdialog.scrltmp" files
46  *        and menus change their size on the fly.
47  *
48  *    *)  If for some reason the last scrolling position is not saved by
49  *        lxdialog, it sets the scrolling so that the selected item is in the
50  *        middle of the menu box, not at the bottom.
51  *
52  * 02 January 1999, Michael Elizabeth Chastain (mec@shout.net)
53  * Reset 'scroll' to 0 if the value from lxdialog.scrltmp is bogus.
54  * This fixes a bug in Menuconfig where using ' ' to descend into menus
55  * would leave mis-synchronized lxdialog.scrltmp files lying around,
56  * fscanf would read in 'scroll', and eventually that value would get used.
57  */
58 
59 #include "dialog.h"
60 
61 static int menu_width, item_x;
62 
63 /*
64  * Print menu item
65  */
66 static void do_print_item(WINDOW * win, const char *item, int line_y,
67                           int selected, int hotkey)
68 {
69 	int j;
70 	char *menu_item = malloc(menu_width + 1);
71 
72 	strncpy(menu_item, item, menu_width - item_x);
73 	menu_item[menu_width - item_x] = '\0';
74 	j = first_alpha(menu_item, "YyNnMmHh");
75 
76 	/* Clear 'residue' of last item */
77 	wattrset(win, dlg.menubox.atr);
78 	wmove(win, line_y, 0);
79 #if OLD_NCURSES
80 	{
81 		int i;
82 		for (i = 0; i < menu_width; i++)
83 			waddch(win, ' ');
84 	}
85 #else
86 	wclrtoeol(win);
87 #endif
88 	wattrset(win, selected ? dlg.item_selected.atr : dlg.item.atr);
89 	mvwaddstr(win, line_y, item_x, menu_item);
90 	if (hotkey) {
91 		wattrset(win, selected ? dlg.tag_key_selected.atr
92 			 : dlg.tag_key.atr);
93 		mvwaddch(win, line_y, item_x + j, menu_item[j]);
94 	}
95 	if (selected) {
96 		wmove(win, line_y, item_x + 1);
97 	}
98 	free(menu_item);
99 	wrefresh(win);
100 }
101 
102 #define print_item(index, choice, selected)				\
103 do {									\
104 	item_set(index);						\
105 	do_print_item(menu, item_str(), choice, selected, !item_is_tag(':')); \
106 } while (0)
107 
108 /*
109  * Print the scroll indicators.
110  */
111 static void print_arrows(WINDOW * win, int item_no, int scroll, int y, int x,
112 			 int height)
113 {
114 	int cur_y, cur_x;
115 
116 	getyx(win, cur_y, cur_x);
117 
118 	wmove(win, y, x);
119 
120 	if (scroll > 0) {
121 		wattrset(win, dlg.uarrow.atr);
122 		waddch(win, ACS_UARROW);
123 		waddstr(win, "(-)");
124 	} else {
125 		wattrset(win, dlg.menubox.atr);
126 		waddch(win, ACS_HLINE);
127 		waddch(win, ACS_HLINE);
128 		waddch(win, ACS_HLINE);
129 		waddch(win, ACS_HLINE);
130 	}
131 
132 	y = y + height + 1;
133 	wmove(win, y, x);
134 	wrefresh(win);
135 
136 	if ((height < item_no) && (scroll + height < item_no)) {
137 		wattrset(win, dlg.darrow.atr);
138 		waddch(win, ACS_DARROW);
139 		waddstr(win, "(+)");
140 	} else {
141 		wattrset(win, dlg.menubox_border.atr);
142 		waddch(win, ACS_HLINE);
143 		waddch(win, ACS_HLINE);
144 		waddch(win, ACS_HLINE);
145 		waddch(win, ACS_HLINE);
146 	}
147 
148 	wmove(win, cur_y, cur_x);
149 	wrefresh(win);
150 }
151 
152 /*
153  * Display the termination buttons.
154  */
155 static void print_buttons(WINDOW * win, int height, int width, int selected)
156 {
157 	int x = width / 2 - 16;
158 	int y = height - 2;
159 
160 	print_button(win, gettext("Select"), y, x, selected == 0);
161 	print_button(win, gettext(" Exit "), y, x + 12, selected == 1);
162 	print_button(win, gettext(" Help "), y, x + 24, selected == 2);
163 
164 	wmove(win, y, x + 1 + 12 * selected);
165 	wrefresh(win);
166 }
167 
168 /* scroll up n lines (n may be negative) */
169 static void do_scroll(WINDOW *win, int *scroll, int n)
170 {
171 	/* Scroll menu up */
172 	scrollok(win, TRUE);
173 	wscrl(win, n);
174 	scrollok(win, FALSE);
175 	*scroll = *scroll + n;
176 	wrefresh(win);
177 }
178 
179 /*
180  * Display a menu for choosing among a number of options
181  */
182 int dialog_menu(const char *title, const char *prompt,
183                 const void *selected, int *s_scroll)
184 {
185 	int i, j, x, y, box_x, box_y;
186 	int height, width, menu_height;
187 	int key = 0, button = 0, scroll = 0, choice = 0;
188 	int first_item =  0, max_choice;
189 	WINDOW *dialog, *menu;
190 
191 do_resize:
192 	height = getmaxy(stdscr);
193 	width = getmaxx(stdscr);
194 	if (height < 15 || width < 65)
195 		return -ERRDISPLAYTOOSMALL;
196 
197 	height -= 4;
198 	width  -= 5;
199 	menu_height = height - 10;
200 
201 	max_choice = MIN(menu_height, item_count());
202 
203 	/* center dialog box on screen */
204 	x = (COLS - width) / 2;
205 	y = (LINES - height) / 2;
206 
207 	draw_shadow(stdscr, y, x, height, width);
208 
209 	dialog = newwin(height, width, y, x);
210 	keypad(dialog, TRUE);
211 
212 	draw_box(dialog, 0, 0, height, width,
213 		 dlg.dialog.atr, dlg.border.atr);
214 	wattrset(dialog, dlg.border.atr);
215 	mvwaddch(dialog, height - 3, 0, ACS_LTEE);
216 	for (i = 0; i < width - 2; i++)
217 		waddch(dialog, ACS_HLINE);
218 	wattrset(dialog, dlg.dialog.atr);
219 	wbkgdset(dialog, dlg.dialog.atr & A_COLOR);
220 	waddch(dialog, ACS_RTEE);
221 
222 	print_title(dialog, title, width);
223 
224 	wattrset(dialog, dlg.dialog.atr);
225 	print_autowrap(dialog, prompt, width - 2, 1, 3);
226 
227 	menu_width = width - 6;
228 	box_y = height - menu_height - 5;
229 	box_x = (width - menu_width) / 2 - 1;
230 
231 	/* create new window for the menu */
232 	menu = subwin(dialog, menu_height, menu_width,
233 		      y + box_y + 1, x + box_x + 1);
234 	keypad(menu, TRUE);
235 
236 	/* draw a box around the menu items */
237 	draw_box(dialog, box_y, box_x, menu_height + 2, menu_width + 2,
238 		 dlg.menubox_border.atr, dlg.menubox.atr);
239 
240 	if (menu_width >= 80)
241 		item_x = (menu_width - 70) / 2;
242 	else
243 		item_x = 4;
244 
245 	/* Set choice to default item */
246 	item_foreach()
247 		if (selected && (selected == item_data()))
248 			choice = item_n();
249 	/* get the saved scroll info */
250 	scroll = *s_scroll;
251 	if ((scroll <= choice) && (scroll + max_choice > choice) &&
252 	   (scroll >= 0) && (scroll + max_choice <= item_count())) {
253 		first_item = scroll;
254 		choice = choice - scroll;
255 	} else {
256 		scroll = 0;
257 	}
258 	if ((choice >= max_choice)) {
259 		if (choice >= item_count() - max_choice / 2)
260 			scroll = first_item = item_count() - max_choice;
261 		else
262 			scroll = first_item = choice - max_choice / 2;
263 		choice = choice - scroll;
264 	}
265 
266 	/* Print the menu */
267 	for (i = 0; i < max_choice; i++) {
268 		print_item(first_item + i, i, i == choice);
269 	}
270 
271 	wnoutrefresh(menu);
272 
273 	print_arrows(dialog, item_count(), scroll,
274 		     box_y, box_x + item_x + 1, menu_height);
275 
276 	print_buttons(dialog, height, width, 0);
277 	wmove(menu, choice, item_x + 1);
278 	wrefresh(menu);
279 
280 	while (key != KEY_ESC) {
281 		key = wgetch(menu);
282 
283 		if (key < 256 && isalpha(key))
284 			key = tolower(key);
285 
286 		if (strchr("ynmh", key))
287 			i = max_choice;
288 		else {
289 			for (i = choice + 1; i < max_choice; i++) {
290 				item_set(scroll + i);
291 				j = first_alpha(item_str(), "YyNnMmHh");
292 				if (key == tolower(item_str()[j]))
293 					break;
294 			}
295 			if (i == max_choice)
296 				for (i = 0; i < max_choice; i++) {
297 					item_set(scroll + i);
298 					j = first_alpha(item_str(), "YyNnMmHh");
299 					if (key == tolower(item_str()[j]))
300 						break;
301 				}
302 		}
303 
304 		if (i < max_choice ||
305 		    key == KEY_UP || key == KEY_DOWN ||
306 		    key == '-' || key == '+' ||
307 		    key == KEY_PPAGE || key == KEY_NPAGE) {
308 			/* Remove highligt of current item */
309 			print_item(scroll + choice, choice, FALSE);
310 
311 			if (key == KEY_UP || key == '-') {
312 				if (choice < 2 && scroll) {
313 					/* Scroll menu down */
314 					do_scroll(menu, &scroll, -1);
315 
316 					print_item(scroll, 0, FALSE);
317 				} else
318 					choice = MAX(choice - 1, 0);
319 
320 			} else if (key == KEY_DOWN || key == '+') {
321 				print_item(scroll+choice, choice, FALSE);
322 
323 				if ((choice > max_choice - 3) &&
324 				    (scroll + max_choice < item_count())) {
325 					/* Scroll menu up */
326 					do_scroll(menu, &scroll, 1);
327 
328 					print_item(scroll+max_choice - 1,
329 						   max_choice - 1, FALSE);
330 				} else
331 					choice = MIN(choice + 1, max_choice - 1);
332 
333 			} else if (key == KEY_PPAGE) {
334 				scrollok(menu, TRUE);
335 				for (i = 0; (i < max_choice); i++) {
336 					if (scroll > 0) {
337 						do_scroll(menu, &scroll, -1);
338 						print_item(scroll, 0, FALSE);
339 					} else {
340 						if (choice > 0)
341 							choice--;
342 					}
343 				}
344 
345 			} else if (key == KEY_NPAGE) {
346 				for (i = 0; (i < max_choice); i++) {
347 					if (scroll + max_choice < item_count()) {
348 						do_scroll(menu, &scroll, 1);
349 						print_item(scroll+max_choice-1,
350 							   max_choice - 1, FALSE);
351 					} else {
352 						if (choice + 1 < max_choice)
353 							choice++;
354 					}
355 				}
356 			} else
357 				choice = i;
358 
359 			print_item(scroll + choice, choice, TRUE);
360 
361 			print_arrows(dialog, item_count(), scroll,
362 				     box_y, box_x + item_x + 1, menu_height);
363 
364 			wnoutrefresh(dialog);
365 			wrefresh(menu);
366 
367 			continue;	/* wait for another key press */
368 		}
369 
370 		switch (key) {
371 		case KEY_LEFT:
372 		case TAB:
373 		case KEY_RIGHT:
374 			button = ((key == KEY_LEFT ? --button : ++button) < 0)
375 			    ? 2 : (button > 2 ? 0 : button);
376 
377 			print_buttons(dialog, height, width, button);
378 			wrefresh(menu);
379 			break;
380 		case ' ':
381 		case 's':
382 		case 'y':
383 		case 'n':
384 		case 'm':
385 		case '/':
386 		case 'h':
387 		case '?':
388 		case 'z':
389 		case '\n':
390 			/* save scroll info */
391 			*s_scroll = scroll;
392 			delwin(menu);
393 			delwin(dialog);
394 			item_set(scroll + choice);
395 			item_set_selected(1);
396 			switch (key) {
397 			case 'h':
398 			case '?':
399 				return 2;
400 			case 's':
401 			case 'y':
402 				return 3;
403 			case 'n':
404 				return 4;
405 			case 'm':
406 				return 5;
407 			case ' ':
408 				return 6;
409 			case '/':
410 				return 7;
411 			case 'z':
412 				return 8;
413 			case '\n':
414 				return button;
415 			}
416 			return 0;
417 		case 'e':
418 		case 'x':
419 			key = KEY_ESC;
420 			break;
421 		case KEY_ESC:
422 			key = on_key_esc(menu);
423 			break;
424 		case KEY_RESIZE:
425 			on_key_resize();
426 			delwin(menu);
427 			delwin(dialog);
428 			goto do_resize;
429 		}
430 	}
431 	delwin(menu);
432 	delwin(dialog);
433 	return key;		/* ESC pressed */
434 }
435