1// SPDX-License-Identifier: GPL-2.0+
2/*
3 *  menubox.c -- implements the menu box
4 *
5 *  ORIGINAL AUTHOR: Savio Lam (lam836@cs.cuhk.hk)
6 *  MODIFIED FOR LINUX KERNEL CONFIG BY: William Roadcap (roadcapw@cfw.com)
7 */
8
9/*
10 *  Changes by Clifford Wolf (god@clifford.at)
11 *
12 *  [ 1998-06-13 ]
13 *
14 *    *)  A bugfix for the Page-Down problem
15 *
16 *    *)  Formerly when I used Page Down and Page Up, the cursor would be set
17 *        to the first position in the menu box.  Now lxdialog is a bit
18 *        smarter and works more like other menu systems (just have a look at
19 *        it).
20 *
21 *    *)  Formerly if I selected something my scrolling would be broken because
22 *        lxdialog is re-invoked by the Menuconfig shell script, can't
23 *        remember the last scrolling position, and just sets it so that the
24 *        cursor is at the bottom of the box.  Now it writes the temporary file
25 *        lxdialog.scrltmp which contains this information. The file is
26 *        deleted by lxdialog if the user leaves a submenu or enters a new
27 *        one, but it would be nice if Menuconfig could make another "rm -f"
28 *        just to be sure.  Just try it out - you will recognise a difference!
29 *
30 *  [ 1998-06-14 ]
31 *
32 *    *)  Now lxdialog is crash-safe against broken "lxdialog.scrltmp" files
33 *        and menus change their size on the fly.
34 *
35 *    *)  If for some reason the last scrolling position is not saved by
36 *        lxdialog, it sets the scrolling so that the selected item is in the
37 *        middle of the menu box, not at the bottom.
38 *
39 * 02 January 1999, Michael Elizabeth Chastain (mec@shout.net)
40 * Reset 'scroll' to 0 if the value from lxdialog.scrltmp is bogus.
41 * This fixes a bug in Menuconfig where using ' ' to descend into menus
42 * would leave mis-synchronized lxdialog.scrltmp files lying around,
43 * fscanf would read in 'scroll', and eventually that value would get used.
44 */
45
46#include "dialog.h"
47
48static int menu_width, item_x;
49
50/*
51 * Print menu item
52 */
53static void do_print_item(WINDOW * win, const char *item, int line_y,
54			  int selected, int hotkey)
55{
56	int j;
57	char *menu_item = malloc(menu_width + 1);
58
59	strncpy(menu_item, item, menu_width - item_x);
60	menu_item[menu_width - item_x] = '\0';
61	j = first_alpha(menu_item, "YyNnMmHh");
62
63	/* Clear 'residue' of last item */
64	wattrset(win, dlg.menubox.atr);
65	wmove(win, line_y, 0);
66#if OLD_NCURSES
67	{
68		int i;
69		for (i = 0; i < menu_width; i++)
70			waddch(win, ' ');
71	}
72#else
73	wclrtoeol(win);
74#endif
75	wattrset(win, selected ? dlg.item_selected.atr : dlg.item.atr);
76	mvwaddstr(win, line_y, item_x, menu_item);
77	if (hotkey) {
78		wattrset(win, selected ? dlg.tag_key_selected.atr
79			 : dlg.tag_key.atr);
80		mvwaddch(win, line_y, item_x + j, menu_item[j]);
81	}
82	if (selected) {
83		wmove(win, line_y, item_x + 1);
84	}
85	free(menu_item);
86	wrefresh(win);
87}
88
89#define print_item(index, choice, selected)				\
90do {									\
91	item_set(index);						\
92	do_print_item(menu, item_str(), choice, selected, !item_is_tag(':')); \
93} while (0)
94
95/*
96 * Print the scroll indicators.
97 */
98static void print_arrows(WINDOW * win, int item_no, int scroll, int y, int x,
99			 int height)
100{
101	int cur_y, cur_x;
102
103	getyx(win, cur_y, cur_x);
104
105	wmove(win, y, x);
106
107	if (scroll > 0) {
108		wattrset(win, dlg.uarrow.atr);
109		waddch(win, ACS_UARROW);
110		waddstr(win, "(-)");
111	} else {
112		wattrset(win, dlg.menubox.atr);
113		waddch(win, ACS_HLINE);
114		waddch(win, ACS_HLINE);
115		waddch(win, ACS_HLINE);
116		waddch(win, ACS_HLINE);
117	}
118
119	y = y + height + 1;
120	wmove(win, y, x);
121	wrefresh(win);
122
123	if ((height < item_no) && (scroll + height < item_no)) {
124		wattrset(win, dlg.darrow.atr);
125		waddch(win, ACS_DARROW);
126		waddstr(win, "(+)");
127	} else {
128		wattrset(win, dlg.menubox_border.atr);
129		waddch(win, ACS_HLINE);
130		waddch(win, ACS_HLINE);
131		waddch(win, ACS_HLINE);
132		waddch(win, ACS_HLINE);
133	}
134
135	wmove(win, cur_y, cur_x);
136	wrefresh(win);
137}
138
139/*
140 * Display the termination buttons.
141 */
142static void print_buttons(WINDOW * win, int height, int width, int selected)
143{
144	int x = width / 2 - 28;
145	int y = height - 2;
146
147	print_button(win, "Select", y, x, selected == 0);
148	print_button(win, " Exit ", y, x + 12, selected == 1);
149	print_button(win, " Help ", y, x + 24, selected == 2);
150	print_button(win, " Save ", y, x + 36, selected == 3);
151	print_button(win, " Load ", y, x + 48, selected == 4);
152
153	wmove(win, y, x + 1 + 12 * selected);
154	wrefresh(win);
155}
156
157/* scroll up n lines (n may be negative) */
158static void do_scroll(WINDOW *win, int *scroll, int n)
159{
160	/* Scroll menu up */
161	scrollok(win, TRUE);
162	wscrl(win, n);
163	scrollok(win, FALSE);
164	*scroll = *scroll + n;
165	wrefresh(win);
166}
167
168/*
169 * Display a menu for choosing among a number of options
170 */
171int dialog_menu(const char *title, const char *prompt,
172		const void *selected, int *s_scroll)
173{
174	int i, j, x, y, box_x, box_y;
175	int height, width, menu_height;
176	int key = 0, button = 0, scroll = 0, choice = 0;
177	int first_item =  0, max_choice;
178	WINDOW *dialog, *menu;
179
180do_resize:
181	height = getmaxy(stdscr);
182	width = getmaxx(stdscr);
183	if (height < MENUBOX_HEIGTH_MIN || width < MENUBOX_WIDTH_MIN)
184		return -ERRDISPLAYTOOSMALL;
185
186	height -= 4;
187	width  -= 5;
188	menu_height = height - 10;
189
190	max_choice = MIN(menu_height, item_count());
191
192	/* center dialog box on screen */
193	x = (getmaxx(stdscr) - width) / 2;
194	y = (getmaxy(stdscr) - height) / 2;
195
196	draw_shadow(stdscr, y, x, height, width);
197
198	dialog = newwin(height, width, y, x);
199	keypad(dialog, TRUE);
200
201	draw_box(dialog, 0, 0, height, width,
202		 dlg.dialog.atr, dlg.border.atr);
203	wattrset(dialog, dlg.border.atr);
204	mvwaddch(dialog, height - 3, 0, ACS_LTEE);
205	for (i = 0; i < width - 2; i++)
206		waddch(dialog, ACS_HLINE);
207	wattrset(dialog, dlg.dialog.atr);
208	wbkgdset(dialog, dlg.dialog.atr & A_COLOR);
209	waddch(dialog, ACS_RTEE);
210
211	print_title(dialog, title, width);
212
213	wattrset(dialog, dlg.dialog.atr);
214	print_autowrap(dialog, prompt, width - 2, 1, 3);
215
216	menu_width = width - 6;
217	box_y = height - menu_height - 5;
218	box_x = (width - menu_width) / 2 - 1;
219
220	/* create new window for the menu */
221	menu = subwin(dialog, menu_height, menu_width,
222		      y + box_y + 1, x + box_x + 1);
223	keypad(menu, TRUE);
224
225	/* draw a box around the menu items */
226	draw_box(dialog, box_y, box_x, menu_height + 2, menu_width + 2,
227		 dlg.menubox_border.atr, dlg.menubox.atr);
228
229	if (menu_width >= 80)
230		item_x = (menu_width - 70) / 2;
231	else
232		item_x = 4;
233
234	/* Set choice to default item */
235	item_foreach()
236		if (selected && (selected == item_data()))
237			choice = item_n();
238	/* get the saved scroll info */
239	scroll = *s_scroll;
240	if ((scroll <= choice) && (scroll + max_choice > choice) &&
241	   (scroll >= 0) && (scroll + max_choice <= item_count())) {
242		first_item = scroll;
243		choice = choice - scroll;
244	} else {
245		scroll = 0;
246	}
247	if ((choice >= max_choice)) {
248		if (choice >= item_count() - max_choice / 2)
249			scroll = first_item = item_count() - max_choice;
250		else
251			scroll = first_item = choice - max_choice / 2;
252		choice = choice - scroll;
253	}
254
255	/* Print the menu */
256	for (i = 0; i < max_choice; i++) {
257		print_item(first_item + i, i, i == choice);
258	}
259
260	wnoutrefresh(menu);
261
262	print_arrows(dialog, item_count(), scroll,
263		     box_y, box_x + item_x + 1, menu_height);
264
265	print_buttons(dialog, height, width, 0);
266	wmove(menu, choice, item_x + 1);
267	wrefresh(menu);
268
269	while (key != KEY_ESC) {
270		key = wgetch(menu);
271
272		if (key < 256 && isalpha(key))
273			key = tolower(key);
274
275		if (strchr("ynmh", key))
276			i = max_choice;
277		else {
278			for (i = choice + 1; i < max_choice; i++) {
279				item_set(scroll + i);
280				j = first_alpha(item_str(), "YyNnMmHh");
281				if (key == tolower(item_str()[j]))
282					break;
283			}
284			if (i == max_choice)
285				for (i = 0; i < max_choice; i++) {
286					item_set(scroll + i);
287					j = first_alpha(item_str(), "YyNnMmHh");
288					if (key == tolower(item_str()[j]))
289						break;
290				}
291		}
292
293		if (item_count() != 0 &&
294		    (i < max_choice ||
295		     key == KEY_UP || key == KEY_DOWN ||
296		     key == '-' || key == '+' ||
297		     key == KEY_PPAGE || key == KEY_NPAGE)) {
298			/* Remove highligt of current item */
299			print_item(scroll + choice, choice, FALSE);
300
301			if (key == KEY_UP || key == '-') {
302				if (choice < 2 && scroll) {
303					/* Scroll menu down */
304					do_scroll(menu, &scroll, -1);
305
306					print_item(scroll, 0, FALSE);
307				} else
308					choice = MAX(choice - 1, 0);
309
310			} else if (key == KEY_DOWN || key == '+') {
311				print_item(scroll+choice, choice, FALSE);
312
313				if ((choice > max_choice - 3) &&
314				    (scroll + max_choice < item_count())) {
315					/* Scroll menu up */
316					do_scroll(menu, &scroll, 1);
317
318					print_item(scroll+max_choice - 1,
319						   max_choice - 1, FALSE);
320				} else
321					choice = MIN(choice + 1, max_choice - 1);
322
323			} else if (key == KEY_PPAGE) {
324				scrollok(menu, TRUE);
325				for (i = 0; (i < max_choice); i++) {
326					if (scroll > 0) {
327						do_scroll(menu, &scroll, -1);
328						print_item(scroll, 0, FALSE);
329					} else {
330						if (choice > 0)
331							choice--;
332					}
333				}
334
335			} else if (key == KEY_NPAGE) {
336				for (i = 0; (i < max_choice); i++) {
337					if (scroll + max_choice < item_count()) {
338						do_scroll(menu, &scroll, 1);
339						print_item(scroll+max_choice-1,
340							   max_choice - 1, FALSE);
341					} else {
342						if (choice + 1 < max_choice)
343							choice++;
344					}
345				}
346			} else
347				choice = i;
348
349			print_item(scroll + choice, choice, TRUE);
350
351			print_arrows(dialog, item_count(), scroll,
352				     box_y, box_x + item_x + 1, menu_height);
353
354			wnoutrefresh(dialog);
355			wrefresh(menu);
356
357			continue;	/* wait for another key press */
358		}
359
360		switch (key) {
361		case KEY_LEFT:
362		case TAB:
363		case KEY_RIGHT:
364			button = ((key == KEY_LEFT ? --button : ++button) < 0)
365			    ? 4 : (button > 4 ? 0 : button);
366
367			print_buttons(dialog, height, width, button);
368			wrefresh(menu);
369			break;
370		case ' ':
371		case 's':
372		case 'y':
373		case 'n':
374		case 'm':
375		case '/':
376		case 'h':
377		case '?':
378		case 'z':
379		case '\n':
380			/* save scroll info */
381			*s_scroll = scroll;
382			delwin(menu);
383			delwin(dialog);
384			item_set(scroll + choice);
385			item_set_selected(1);
386			switch (key) {
387			case 'h':
388			case '?':
389				return 2;
390			case 's':
391			case 'y':
392				return 5;
393			case 'n':
394				return 6;
395			case 'm':
396				return 7;
397			case ' ':
398				return 8;
399			case '/':
400				return 9;
401			case 'z':
402				return 10;
403			case '\n':
404				return button;
405			}
406			return 0;
407		case 'e':
408		case 'x':
409			key = KEY_ESC;
410			break;
411		case KEY_ESC:
412			key = on_key_esc(menu);
413			break;
414		case KEY_RESIZE:
415			on_key_resize();
416			delwin(menu);
417			delwin(dialog);
418			goto do_resize;
419		}
420	}
421	delwin(menu);
422	delwin(dialog);
423	return key;		/* ESC pressed */
424}
425