/*	$NetBSD: menu_sys.def,v 1.37 2003/06/03 11:51:56 dsl Exp $	*/

/*
 * Copyright 1997 Piermont Information Systems Inc.
 * All rights reserved.
 *
 * Written by Philip A. Nelson for Piermont Information Systems Inc.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software develooped for the NetBSD Project by
 *      Piermont Information Systems Inc.
 * 4. The name of Piermont Information Systems Inc. may not be used to endorse
 *    or promote products derived from this software without specific prior
 *    written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY PIERMONT INFORMATION SYSTEMS INC. ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL PIERMONT INFORMATION SYSTEMS INC. BE 
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF 
 * THE POSSIBILITY OF SUCH DAMAGE.
 *
 */

/* menu_sys.defs -- Menu system standard routines. */

#include <string.h>
#include <ctype.h>

#define REQ_EXECUTE    1000
#define REQ_NEXT_ITEM  1001
#define REQ_PREV_ITEM  1002
#define REQ_REDISPLAY  1003
#define REQ_SCROLLDOWN 1004
#define REQ_SCROLLUP   1005
#define REQ_HELP       1006

/* Macros */
#define MAX(x,y) ((x)>(y)?(x):(y))
#define MIN(x,y) ((x)<(y)?(x):(y))

/* Initialization state. */
static int __menu_init = 0;
int __m_endwin = 0;
static int max_lines = 0, max_cols = 0;
static char *scrolltext = " <: page up, >: page down";

static menudesc *menus = menu_def;

#ifdef DYNAMIC_MENUS
static int num_menus  = 0;
static int num_avail  = 0;
#define DYN_INIT_NUM 32
#endif

/* prototypes for in here! */
static void init_menu(struct menudesc *m);
static char opt_ch(int op_no);
static void draw_menu(struct menudesc *m);
static void process_help(struct menudesc *m, int num);
static void process_req(struct menudesc *m, int num, int req);
static int menucmd(WINDOW *w);

#ifndef NULL
#define NULL 0
#endif

/* menu system processing routines */
#define mbeep() (void)fputc('\a', stderr)

static int
menucmd(WINDOW *w)
{
	int ch;

	while (TRUE) {
		ch = wgetch(w);
		
		switch (ch) {
		case '\n':
			return REQ_EXECUTE;
		case '\016':  /* Control-P */
		case KEY_DOWN:
			return REQ_NEXT_ITEM;
		case '\020':  /* Control-N */
		case KEY_UP:
			return REQ_PREV_ITEM;
		case '\014':  /* Control-L */
			return REQ_REDISPLAY;
		case '<':
		case '\010':  /* Control-H (backspace) */
		case KEY_PPAGE:
		case KEY_LEFT:
			return REQ_SCROLLUP;
		case '\026':  /* Control-V */
		case '>':
		case ' ':
		case KEY_NPAGE:
		case KEY_RIGHT:
			return REQ_SCROLLDOWN;
		case '?':
			return REQ_HELP;
		case '\033': /* esc-v is scroll down */
			ch = wgetch(w);
			if (ch == 'v')
				return REQ_SCROLLUP;
			else
				ch = 0; /* zap char so we beep */
		}
		
		if (isalpha(ch)) 
			return ch;

		mbeep();
		wrefresh(w);
	}
}

static void
init_menu(struct menudesc *m)
{
	int wmax;
	int hadd, wadd, exithadd;
	int i;

	hadd = ((m->mopt & MC_NOBOX) ? 0 : 2);
	wadd = ((m->mopt & MC_NOBOX) ? 2 : 4);

	hadd += strlen(m->title) != 0 ? 2 : 0;
	exithadd = ((m->mopt & MC_NOEXITOPT) ? 0 : 1);

	wmax = strlen(m->title);

	/* Calculate h? h == number of visible options. */
	if (m->h == 0) {
		m->h = m->numopts + exithadd;
		if (m->h + m->y + hadd >= max_lines && (m->mopt & MC_SCROLL)) {
			hadd++;
			m->h = max_lines - m->y - hadd;
		}
	}

	/* Check window heights and set scrolling */
	if (m->h < m->numopts + exithadd) {
		if (!(m->mopt & MC_SCROLL) || m->h < 3) {
			endwin();
			(void)fprintf(stderr,
				"Window too short for menu \"%s\"\n",
				m->title);
			exit(1);
		}
	} else
		m->mopt &= ~MC_SCROLL;

	/* check for screen fit */
	if (m->y + m->h + hadd > max_lines) {
		endwin();
		(void)fprintf(stderr,
			"Screen too short for menu \"%s\"\n", m->title);
		exit(1);

	}

	/* Calculate w? */
	if (m->w == 0) {
		if (m->mopt & MC_SCROLL)
			wmax = MAX(wmax,strlen(scrolltext));
		for (i = 0; i < m->numopts; i++)
			wmax = MAX(wmax, strlen(m->opts[i].opt_name) + 3);
		m->w = wmax;
	}

	/* check and adjust for screen fit */
	if (m->w + wadd > max_cols) {
		endwin();
		(void)fprintf(stderr,
			"Screen too narrow for menu \"%s\"\n", m->title);
		exit(1);

	}
	if (m->x == -1)
		m->x = (max_cols - (m->w + wadd)) / 2;	/* center */
	else if (m->x + m->w + wadd > max_cols)
		m->x = max_cols - (m->w + wadd);

	/* Get the windows. */
	m->mw = newwin(m->h + hadd, m->w + wadd, m->y, m->x);
	keypad(m->mw, TRUE); /* enable multi-key assembling for win */

	if (m->mw == NULL) {
		endwin();
		(void)fprintf(stderr,
			"Could not create window for menu \"%s\"\n", m->title);
		exit(1);
	}

	/* XXX is it even worth doing this right? */
	if (has_colors()) {
		wbkgd(m->mw, COLOR_PAIR(1));
		wattrset(m->mw, COLOR_PAIR(1));
	}
}

static char
opt_ch(int op_no)
{
	char c;
	if (op_no < 25) {
		c = 'a' + op_no;
		if (c >= 'x')
			c++;
	} else 
		c = 'A' + op_no - 25;
	return c;
}

static void
draw_menu_line(struct menudesc *m, int i, int cury, char opt, const char *text)
{
	int hasbox = m->mopt & MC_NOBOX ? 0 : 1;

	if (m->cursel == i) {
		mvwaddstr(m->mw, cury, hasbox, ">");
		wstandout(m->mw);
	} else
		mvwaddstr(m->mw, cury, hasbox, " ");
	if (!(m->mopt & MC_NOSHORTCUT))
		wprintw(m->mw, "%c: ", opt);
	waddstr(m->mw, text);
	if (m->cursel == i)
		wstandend(m->mw);
}

static void
draw_menu(struct menudesc *m)
{
	int i;
	int hasbox, cury, maxy;
	int tadd;
	
	if (m->mopt & MC_NOBOX) {
		cury = 0;
		maxy = m->h;
		hasbox = 0;
	} else {
		cury = 1;
		maxy = m->h + 1;
		hasbox = 1;
	}

	/* Clear the window */
	wclear(m->mw);

	tadd = strlen(m->title) ? 2 : 0;

	if (tadd) {
		mvwaddstr(m->mw, hasbox, hasbox, " ");
		mvwaddstr(m->mw, hasbox, hasbox + 1, m->title);
		cury += tadd;
		maxy += tadd;
	}

	for (i = m->topline; i < m->numopts; i++) {
		if (cury >= maxy)
			break;
		draw_menu_line(m, i, cury++, opt_ch(i), m->opts[i].opt_name);
	}

	/* Add the exit option. */
	if (!(m->mopt & MC_NOEXITOPT) && cury < maxy)
		draw_menu_line(m, m->numopts, cury++, 'x', m->exitstr);

	/* Add the scroll line */
	if (m->mopt & MC_SCROLL)
		mvwaddstr(m->mw, cury, hasbox, scrolltext);

	/* Add the box. */
	if (!(m->mopt & MC_NOBOX))
		box(m->mw, 0, 0);

	wmove(m->mw, tadd + hasbox + m->cursel - m->topline, hasbox);
	wrefresh(m->mw);
}

static void
/*ARGSUSED*/
process_help(struct menudesc *m, int num)
{
	const char *help = m->helpstr;
	int lineoff = 0;
	int curoff = 0;
	int again;
	int winin;

	/* Is there help? */
	if (!help) {
		mbeep();
		return;
	}

	/* Display the help information. */
	do {
		if (lineoff < curoff) {
			help = m->helpstr;
			curoff = 0;
		}
		while (*help && curoff < lineoff) {
			if (*help == '\n')
				curoff++;
			help++;
		}
	
		wclear(stdscr);
		mvwaddstr(stdscr, 0, 0, 
			"Help: exit: x,  page up: u <, page down: d >");
		mvwaddstr(stdscr, 2, 0, help);
		wmove(stdscr, 1, 0);
		wrefresh(stdscr);

		do {
			winin = wgetch(stdscr);
			if (winin < KEY_MIN)
				winin = tolower(winin);
			again = 0;
			switch (winin) {
				case '<':
				case 'u':
				case KEY_UP:
				case KEY_LEFT:
				case KEY_PPAGE:
					if (lineoff)
						lineoff -= max_lines - 2;
					else
						again = 1;
					break;
				case '>':
				case 'd':
				case KEY_DOWN:
				case KEY_RIGHT:
				case KEY_NPAGE:
					if (*help)
						lineoff += max_lines - 2;
					else
						again = 1;
					break;
				case 'q':
					break;
				case 'x':
					winin = 'q';
					break;
				default:
					again = 1;
			}
			if (again)
				mbeep();
		} while (again);
	} while (winin != 'q');

	/* Restore current menu */    
	wclear(stdscr);
	wrefresh(stdscr);
	if (m->post_act)
		(*m->post_act)();
}

static void
process_req(struct menudesc *m, int num, int req)
{
	int ch;
	int hasexit = (m->mopt & MC_NOEXITOPT ? 0 : 1);

	switch(req) {

	case REQ_EXECUTE:
		return;

	case REQ_NEXT_ITEM:
		if (m->cursel >= m->numopts + hasexit - 1) {
			mbeep();
			return;
		}
		m->cursel++;
		if (m->mopt & MC_SCROLL && m->cursel >= m->topline + m->h)
			m->topline += 1;
		break;

	case REQ_PREV_ITEM:
		if (m->cursel <= 0) {
			mbeep();
			return;
		}
		m->cursel--;
		if (m->cursel < m->topline)
			m->topline -= 1;
		break;

	case REQ_REDISPLAY:
		wclear(stdscr);
		wrefresh(stdscr);
		if (m->post_act)
			(*m->post_act)();
		break;

	case REQ_HELP:
		process_help(m, num);
		break;

	case REQ_SCROLLUP:
		if (m->cursel == 0) {
			mbeep();
			return;
		}
		m->topline = MAX(0, m->topline - m->h);
		m->cursel = MAX(0, m->cursel - m->h);
		wclear(m->mw);
		break;

	case REQ_SCROLLDOWN:
		if (m->cursel >= m->numopts + hasexit - 1) {
			mbeep();
			return;
		}
		m->topline = MIN(m->topline + m->h,
				 m->numopts + hasexit - m->h);
		m->cursel = MIN(m->numopts + hasexit - 1, m->cursel + m->h);
		wclear(m->mw);
		break;

	default:
		ch = req;
		if (ch == 'x' && hasexit) {
			m->cursel = m->numopts;
			break;
		}
		if (m->mopt & MC_NOSHORTCUT) {
			mbeep();
			return;
		}
		if (ch > 'z')
			ch = 255;
		if (ch >= 'a') {
			if (ch > 'x')
				ch--;
			ch = ch - 'a';
		} else
			ch = 25 + ch - 'A';
		if (ch < 0 || ch >= m->numopts) {
			mbeep();
			return;
		}
		m->cursel = ch;
	}

	while (m->cursel >= m->topline + m->h)
		m->topline = MIN(m->topline + m->h,
				 m->numopts + hasexit - m->h);
	while (m->cursel < m->topline)
		m->topline = MAX(0, m->topline - m->h);

	draw_menu(m);
}

int
menu_init(void)
{

	if (__menu_init)
		return 0;

#ifdef	USER_MENU_INIT
	if (USER_MENU_INIT)
		return 1;
#endif

	if (initscr() == NULL)
		return 1;

	cbreak();
	noecho();

	/* XXX Should be configurable but it almost isn't worth it. */
	if (has_colors()) {
		start_color();
		init_pair(1, COLOR_WHITE, COLOR_BLUE);
		bkgd(COLOR_PAIR(1));
		attrset(COLOR_PAIR(1));
	}

	max_lines = getmaxy(stdscr);
	max_cols = getmaxx(stdscr);
	keypad(stdscr, TRUE);
#ifdef DYNAMIC_MENUS
	num_menus = DYN_INIT_NUM;
	while (num_menus < DYN_MENU_START)
		num_menus *= 2;
	menus = malloc(sizeof(menudesc) * num_menus);
	if (menus == NULL)
		return 2;
	(void)memset(menus, 0, sizeof(menudesc) * num_menus);
	(void)memcpy(menus, menu_def, sizeof(menudesc) * DYN_MENU_START);
	num_avail = num_menus - DYN_MENU_START;
#endif

	__menu_init = 1;
	return 0;
}

void
process_menu(int num, void *arg)
{
	int sel = 0;
	int req, done;
	int last_num;
	menu_ent *opt;

	struct menudesc *m;

	m = &menus[num];

	done = FALSE;

	/* Initialize? */
	if (menu_init()) {
		__menu_initerror();
		return;
	}

	if (__m_endwin) {
     		wclear(stdscr);
		wrefresh(stdscr);
		__m_endwin = 0;
	}
	if (m->mw == NULL)
		init_menu(m);

	/* Always preselect option 0 and display from 0! */
	m->cursel = 0;
	m->topline = 0;

	while (!done) {
		last_num = num;
		if (__m_endwin) {
			wclear(stdscr);
			wrefresh(stdscr);
			__m_endwin = 0;
		}
		/* Process the display action */
		if (m->post_act)
			(*m->post_act)();
		draw_menu(m);

		while ((req = menucmd(m->mw)) != REQ_EXECUTE)
			process_req(m, num, req);

		sel = m->cursel;
		wclear(m->mw);
		wrefresh(m->mw);

		/* Process the items */
		if (sel < m->numopts) {
			opt = &m->opts[sel];
			if (opt->opt_flags & OPT_ENDWIN) {
				endwin();
				__m_endwin = 1;
			}
			if (opt->opt_action)
				done = (*opt->opt_action)(m, opt, arg);
			if (opt->opt_menu != -1) {
				if (opt->opt_flags & OPT_SUB)
					process_menu(opt->opt_menu, arg);
				else
					num = opt->opt_menu;
			}

                        if (opt->opt_flags & OPT_EXIT) 
                                done = TRUE;
 				
		} else
			done = TRUE;

		/* Reselect m just in case */
		if (num != last_num) {
			m = &menus[num];

			/* Initialize? */
			if (m->mw == NULL)
				init_menu(m);
			if (m->post_act)
				(*m->post_act)();
		}
	}

	/* Process the exit action */
	if (m->exit_act)
		(*m->exit_act)();
}

/* Control L is end of standard routines, remaining only for dynamic. */

/* Beginning of routines for dynamic menus. */

static int 
double_menus(void)
{
	menudesc *temp;

	temp  = malloc(sizeof(menudesc) * num_menus * 2);
	if (temp == NULL)
		return 0;
	(void)memset(temp, 0, sizeof(menudesc) * num_menus * 2);
	(void)memcpy(temp, menus, sizeof(menudesc) * num_menus);
	free(menus);
	menus = temp;
	num_avail = num_menus;
	num_menus *= 2;

	return 1;
}

int
new_menu(char * title, menu_ent * opts, int numopts, 
	int x, int y, int h, int w, int mopt,
	void (*post_act)(void), void (*exit_act)(void), char * help)
{
	int ix;

	/* Check for free menu entry. */
	if (num_avail == 0)
		if (!double_menus())
			return -1;

	/* Find free menu entry. */
	for (ix = DYN_MENU_START; ix < num_menus && menus[ix].mopt & MC_VALID;
		ix++) /* do  nothing */;

	/* if ix == num_menus ... panic */

	/* Set Entries */
	menus[ix].title = title ? title : "";
	menus[ix].opts = opts;
	menus[ix].numopts = numopts;
	menus[ix].x = x;
	menus[ix].y = y;
	menus[ix].h = h;
	menus[ix].w = w;
	menus[ix].mopt = mopt | MC_VALID;
	menus[ix].post_act = post_act;
	menus[ix].exit_act = exit_act;
	menus[ix].helpstr  = help;
	menus[ix].exitstr  = "Exit";

	init_menu(&menus[ix]);

	return ix;
}

void
free_menu(int menu_no)
{
	if (menu_no < num_menus) {
		menus[menu_no].mopt &= ~MC_VALID;
		if (menus[menu_no].mw != NULL)
			delwin(menus[menu_no].mw);
	}
}