/*

  *  menubox.c -- implements the menu box

  *

  *  ORIGINAL AUTHOR: Savio Lam (lam836@cs.cuhk.hk)

  *  MODIFIED FOR LINUX KERNEL CONFIG BY: William Roadcap (roadcapw@cfw.com)

  *

  *  This program 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 2

  *  of the License, or (at your option) any later version.

  *

  *  This program 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 this program; if not, write to the Free Software

  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

  */

 /*

  *  Changes by Clifford Wolf (god@clifford.at)

  *

  *  [ 1998-06-13 ]

  *

  *    *)  A bugfix for the Page-Down problem

  *

  *    *)  Formerly when I used Page Down and Page Up, the cursor would be set 

  *        to the first position in the menu box.  Now lxdialog is a bit

  *        smarter and works more like other menu systems (just have a look at

  *        it).

  *

  *    *)  Formerly if I selected something my scrolling would be broken because

  *        lxdialog is re-invoked by the Menuconfig shell script, can't

  *        remember the last scrolling position, and just sets it so that the

  *        cursor is at the bottom of the box.  Now it writes the temporary file

  *        lxdialog.scrltmp which contains this information. The file is

  *        deleted by lxdialog if the user leaves a submenu or enters a new

  *        one, but it would be nice if Menuconfig could make another "rm -f"

  *        just to be sure.  Just try it out - you will recognise a difference!

  *

  *  [ 1998-06-14 ]

  *

  *    *)  Now lxdialog is crash-safe against broken "lxdialog.scrltmp" files

  *        and menus change their size on the fly.

  *

  *    *)  If for some reason the last scrolling position is not saved by

  *        lxdialog, it sets the scrolling so that the selected item is in the

  *        middle of the menu box, not at the bottom.

  *

  * 02 January 1999, Michael Elizabeth Chastain (mec@shout.net)

  * Reset 'scroll' to 0 if the value from lxdialog.scrltmp is bogus.

  * This fixes a bug in Menuconfig where using ' ' to descend into menus

  * would leave mis-synchronized lxdialog.scrltmp files lying around,

  * fscanf would read in 'scroll', and eventually that value would get used.

  */

 #include "dialog.h"

 static int menu_width, item_x;

 /*

  * Print menu item

  */

 static void do_print_item(WINDOW * win, const char *item, int line_y,

                           int selected, int hotkey)

 {

 	int j;

 	char *menu_item = malloc(menu_width + 1);

 	strncpy(menu_item, item, menu_width - item_x);

 	menu_item[menu_width - item_x] = '\0';

 	j = first_alpha(menu_item, "YyNnMmHh");

 	/* Clear 'residue' of last item */

 	wattrset(win, dlg.menubox.atr);

 	wmove(win, line_y, 0);

 #if OLD_NCURSES

 	{

 		int i;

 		for (i = 0; i < menu_width; i++)

 			waddch(win, ' ');

 	}

 #else

 	wclrtoeol(win);

 #endif

 	wattrset(win, selected ? dlg.item_selected.atr : dlg.item.atr);

 	mvwaddstr(win, line_y, item_x, menu_item);

 	if (hotkey) {

 		wattrset(win, selected ? dlg.tag_key_selected.atr

 			 : dlg.tag_key.atr);

 		mvwaddch(win, line_y, item_x + j, menu_item[j]);

 	}

 	if (selected) {

 		wmove(win, line_y, item_x + 1);

 	}

 	free(menu_item);

 	wrefresh(win);

 }

 #define print_item(index, choice, selected)				\

 do {									\

 	item_set(index);						\

 	do_print_item(menu, item_str(), choice, selected, !item_is_tag(':')); \

 } while (0)

 /*

  * Print the scroll indicators.

  */

 static void print_arrows(WINDOW * win, int item_no, int scroll, int y, int x,

 			 int height)

 {

 	int cur_y, cur_x;

 	getyx(win, cur_y, cur_x);

 	wmove(win, y, x);

 	if (scroll > 0) {

 		wattrset(win, dlg.uarrow.atr);

 		waddch(win, ACS_UARROW);

 		waddstr(win, "(-)");

 	} else {

 		wattrset(win, dlg.menubox.atr);

 		waddch(win, ACS_HLINE);

 		waddch(win, ACS_HLINE);

 		waddch(win, ACS_HLINE);

 		waddch(win, ACS_HLINE);

 	}

 	y = y + height + 1;

 	wmove(win, y, x);

 	wrefresh(win);

 	if ((height < item_no) && (scroll + height < item_no)) {

 		wattrset(win, dlg.darrow.atr);

 		waddch(win, ACS_DARROW);

 		waddstr(win, "(+)");

 	} else {

 		wattrset(win, dlg.menubox_border.atr);

 		waddch(win, ACS_HLINE);

 		waddch(win, ACS_HLINE);

 		waddch(win, ACS_HLINE);

 		waddch(win, ACS_HLINE);

 	}

 	wmove(win, cur_y, cur_x);

 	wrefresh(win);

 }

 /*

  * Display the termination buttons.

  */

 static void print_buttons(WINDOW * win, int height, int width, int selected)

 {

 	int x = width / 2 - 16;

 	int y = height - 2;

 	print_button(win, gettext("Select"), y, x, selected == 0);

 	print_button(win, gettext(" Exit "), y, x + 12, selected == 1);

 	print_button(win, gettext(" Help "), y, x + 24, selected == 2);

 	wmove(win, y, x + 1 + 12 * selected);

 	wrefresh(win);

 }

 /* scroll up n lines (n may be negative) */

 static void do_scroll(WINDOW *win, int *scroll, int n)

 {

 	/* Scroll menu up */

 	scrollok(win, TRUE);

 	wscrl(win, n);

 	scrollok(win, FALSE);

 	*scroll = *scroll + n;

 	wrefresh(win);

 }

 /*

  * Display a menu for choosing among a number of options

  */

 int dialog_menu(const char *title, const char *prompt,

                 const void *selected, int *s_scroll)

 {

 	int i, j, x, y, box_x, box_y;

 	int height, width, menu_height;

 	int key = 0, button = 0, scroll = 0, choice = 0;

 	int first_item =  0, max_choice;

 	WINDOW *dialog, *menu;

 do_resize:

 	height = getmaxy(stdscr);

 	width = getmaxx(stdscr);

 	if (height < 15 || width < 65)

 		return -ERRDISPLAYTOOSMALL;

 	height -= 4;

 	width  -= 5;

 	menu_height = height - 10;

 	max_choice = MIN(menu_height, item_count());

 	/* center dialog box on screen */

 	x = (COLS - width) / 2;

 	y = (LINES - height) / 2;

 	draw_shadow(stdscr, y, x, height, width);

 	dialog = newwin(height, width, y, x);

 	keypad(dialog, TRUE);

 	draw_box(dialog, 0, 0, height, width,

 		 dlg.dialog.atr, dlg.border.atr);

 	wattrset(dialog, dlg.border.atr);

 	mvwaddch(dialog, height - 3, 0, ACS_LTEE);

 	for (i = 0; i < width - 2; i++)

 		waddch(dialog, ACS_HLINE);

 	wattrset(dialog, dlg.dialog.atr);

 	wbkgdset(dialog, dlg.dialog.atr & A_COLOR);

 	waddch(dialog, ACS_RTEE);

 	print_title(dialog, title, width);

 	wattrset(dialog, dlg.dialog.atr);

 	print_autowrap(dialog, prompt, width - 2, 1, 3);

 	menu_width = width - 6;

 	box_y = height - menu_height - 5;

 	box_x = (width - menu_width) / 2 - 1;

 	/* create new window for the menu */

 	menu = subwin(dialog, menu_height, menu_width,

 		      y + box_y + 1, x + box_x + 1);

 	keypad(menu, TRUE);

 	/* draw a box around the menu items */

 	draw_box(dialog, box_y, box_x, menu_height + 2, menu_width + 2,

 		 dlg.menubox_border.atr, dlg.menubox.atr);

 	if (menu_width >= 80)

 		item_x = (menu_width - 70) / 2;

 	else

 		item_x = 4;

 	/* Set choice to default item */

 	item_foreach()

 		if (selected && (selected == item_data()))

 			choice = item_n();

 	/* get the saved scroll info */

 	scroll = *s_scroll;

 	if ((scroll <= choice) && (scroll + max_choice > choice) &&

 	   (scroll >= 0) && (scroll + max_choice <= item_count())) {

 		first_item = scroll;

 		choice = choice - scroll;

 	} else {

 		scroll = 0;

 	}

 	if ((choice >= max_choice)) {

 		if (choice >= item_count() - max_choice / 2)

 			scroll = first_item = item_count() - max_choice;

 		else

 			scroll = first_item = choice - max_choice / 2;

 		choice = choice - scroll;

 	}

 	/* Print the menu */

 	for (i = 0; i < max_choice; i++) {

 		print_item(first_item + i, i, i == choice);

 	}

 	wnoutrefresh(menu);

 	print_arrows(dialog, item_count(), scroll,

 		     box_y, box_x + item_x + 1, menu_height);

 	print_buttons(dialog, height, width, 0);

 	wmove(menu, choice, item_x + 1);

 	wrefresh(menu);

 	while (key != KEY_ESC) {

 		key = wgetch(menu);

 		if (key < 256 && isalpha(key))

 			key = tolower(key);

 		if (strchr("ynmh", key))

 			i = max_choice;

 		else {

 			for (i = choice + 1; i < max_choice; i++) {

 				item_set(scroll + i);

 				j = first_alpha(item_str(), "YyNnMmHh");

 				if (key == tolower(item_str()[j]))

 					break;

 			}

 			if (i == max_choice)

 				for (i = 0; i < max_choice; i++) {

 					item_set(scroll + i);

 					j = first_alpha(item_str(), "YyNnMmHh");

 					if (key == tolower(item_str()[j]))

 						break;

 				}

 		}

 		if (i < max_choice ||

 		    key == KEY_UP || key == KEY_DOWN ||

 		    key == '-' || key == '+' ||

 		    key == KEY_PPAGE || key == KEY_NPAGE) {

 			/* Remove highligt of current item */

 			print_item(scroll + choice, choice, FALSE);

 			if (key == KEY_UP || key == '-') {

 				if (choice < 2 && scroll) {

 					/* Scroll menu down */

 					do_scroll(menu, &scroll, -1);

 					print_item(scroll, 0, FALSE);

 				} else

 					choice = MAX(choice - 1, 0);

 			} else if (key == KEY_DOWN || key == '+') {

 				print_item(scroll+choice, choice, FALSE);

 				if ((choice > max_choice - 3) &&

 				    (scroll + max_choice < item_count())) {

 					/* Scroll menu up */

 					do_scroll(menu, &scroll, 1);

 					print_item(scroll+max_choice - 1,

 						   max_choice - 1, FALSE);

 				} else

 					choice = MIN(choice + 1, max_choice - 1);

 			} else if (key == KEY_PPAGE) {

 				scrollok(menu, TRUE);

 				for (i = 0; (i < max_choice); i++) {

 					if (scroll > 0) {

 						do_scroll(menu, &scroll, -1);

 						print_item(scroll, 0, FALSE);

 					} else {

 						if (choice > 0)

 							choice--;

 					}

 				}

 			} else if (key == KEY_NPAGE) {

 				for (i = 0; (i < max_choice); i++) {

 					if (scroll + max_choice < item_count()) {

 						do_scroll(menu, &scroll, 1);

 						print_item(scroll+max_choice-1,

 							   max_choice - 1, FALSE);

 					} else {

 						if (choice + 1 < max_choice)

 							choice++;

 					}

 				}

 			} else

 				choice = i;

 			print_item(scroll + choice, choice, TRUE);

 			print_arrows(dialog, item_count(), scroll,

 				     box_y, box_x + item_x + 1, menu_height);

 			wnoutrefresh(dialog);

 			wrefresh(menu);

 			continue;	/* wait for another key press */

 		}

 		switch (key) {

 		case KEY_LEFT:

 		case TAB:

 		case KEY_RIGHT:

 			button = ((key == KEY_LEFT ? --button : ++button) < 0)

 			    ? 2 : (button > 2 ? 0 : button);

 			print_buttons(dialog, height, width, button);

 			wrefresh(menu);

 			break;

 		case ' ':

 		case 's':

 		case 'y':

 		case 'n':

 		case 'm':

 		case '/':

 			/* save scroll info */

 			*s_scroll = scroll;

 			delwin(menu);

 			delwin(dialog);

 			item_set(scroll + choice);

 			item_set_selected(1);

 			switch (key) {

 			case 's':

 				return 3;

 			case 'y':

 				return 3;

 			case 'n':

 				return 4;

 			case 'm':

 				return 5;

 			case ' ':

 				return 6;

 			case '/':

 				return 7;

 			}

 			return 0;

 		case 'h':

 		case '?':

 			button = 2;

 		case '\n':

 			*s_scroll = scroll;

 			delwin(menu);

 			delwin(dialog);

 			item_set(scroll + choice);

 			item_set_selected(1);

 			return button;

 		case 'e':

 		case 'x':

 			key = KEY_ESC;

 			break;

 		case KEY_ESC:

 			key = on_key_esc(menu);

 			break;

 		case KEY_RESIZE:

 			on_key_resize();

 			delwin(menu);

 			delwin(dialog);

 			goto do_resize;

 		}

 	}

 	delwin(menu);

 	delwin(dialog);

 	return key;		/* ESC pressed */

 }