/*	$NetBSD: menu_sys.def,v 1.30 2003/01/10 20:00:50 christos 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 post_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 (void *)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':  /* Contnrol-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:
			return REQ_SCROLLUP;
		case '\026':
		case '>':
		case ' ':
		case KEY_NPAGE:
			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))
			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 (char) c;
}

static void
post_menu (struct menudesc *m)
{
	int i;
	int hasbox, cury, maxy, selrow, lastopt;
	int tadd;
	char optstr[5];
	
	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, cury, cury, " ");
		mvwaddstr(m->mw, cury, cury + 1, m->title);
		cury += 2;
		maxy += 2;
	}

	/* Set defaults, calculate lastopt. */
	selrow = -1;
	if (m->mopt & MC_SCROLL) {
		lastopt = MIN(m->numopts, m->topline+m->h-1);
		maxy -= 1;
	} else
		lastopt = m->numopts;

	for (i=m->topline; i<lastopt; i++, cury++) {
		if (m->cursel == i) {
			mvwaddstr (m->mw, cury, hasbox, ">");
			wstandout(m->mw);
			selrow = cury;
		} else
			mvwaddstr (m->mw, cury, hasbox, " ");
		if (!(m->mopt & MC_NOSHORTCUT)) {
			(void) sprintf (optstr, "%c: ", opt_ch(i));
		    	waddstr (m->mw, optstr);
		}
		waddstr (m->mw, m->opts[i].opt_name);
		if (m->cursel == i)
			wstandend(m->mw);
	}

	/* Add the exit option. */
	if (!(m->mopt & MC_NOEXITOPT) && cury < maxy) {
		if (m->cursel >= m->numopts) {
			mvwaddstr (m->mw, cury, hasbox, ">");
			wstandout(m->mw);
			selrow = cury;
		} else
			mvwaddstr (m->mw, cury, hasbox, " ");
		if (!(m->mopt & MC_NOSHORTCUT))
			waddstr (m->mw, "x: ");
		waddstr (m->mw, m->exitstr);
		if (m->cursel >= m->numopts)
			wstandend(m->mw);
		cury++;
	}

	/* Add the scroll line */
	if (m->mopt & MC_SCROLL) {
		mvwaddstr (m->mw, cury, hasbox, scrolltext);
		if (selrow < 0)
			selrow = cury;
	}

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

	wmove(m->mw, selrow, hasbox);
}

static void
/*ARGSUSED*/
process_help (struct menudesc *m, int num)
{
	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 );
	int refr = 0;
	int scroll_sel = 0;

	if (req == REQ_EXECUTE)
		return;

	else if (req == REQ_NEXT_ITEM) {
		if (m->cursel < m->numopts + hasexit - 1) {
			m->cursel++;
			scroll_sel = 1;
			refr = 1;
			if (m->mopt & MC_SCROLL && 
			    m->cursel >= m->topline + m->h -1 )
				m->topline += 1;
		} else
			mbeep();

	} else if (req == REQ_PREV_ITEM) {
		if (m->cursel > 0) {
			m->cursel--;
			scroll_sel = 1;
			refr = 1;
			if (m->cursel < m->topline )
				m->topline -= 1;
		} else
			mbeep();

	} else if (req == REQ_REDISPLAY) {
		wclear(stdscr);
		wrefresh(stdscr);
		if (m->post_act)
			(*m->post_act)();
		refr = 1;

	} else if (req == REQ_HELP) {
		process_help (m, num);
		refr = 1;

	} else if (req == REQ_SCROLLUP) {
		if (!(m->mopt & MC_SCROLL))
			mbeep();
		else if (m->topline == 0)
			mbeep();
		else {
			m->topline = MAX(0,m->topline-m->h+1);
			m->cursel = MAX(0, m->cursel-m->h+1);
			wclear (m->mw);
			refr = 1;
		}

	} else if (req == REQ_SCROLLDOWN) {
		if (!(m->mopt & MC_SCROLL))
			mbeep();
		else if (m->topline + m->h - 1 >= m->numopts + hasexit)
			mbeep();
		else {
			m->topline = MIN(m->topline+m->h-1,
					 m->numopts+hasexit-m->h+1);
			m->cursel = MIN(m->numopts-1, m->cursel+m->h-1);
			wclear (m->mw);
			refr = 1;
		}

	} else {
		ch = req;
		if (ch == 'x' && hasexit) {
			m->cursel = m->numopts;
			scroll_sel = 1;
			refr = 1;
		} else 
			if (!(m->mopt & MC_NOSHORTCUT)) {
				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();
				else {
					m->cursel = ch;
					scroll_sel = 1;
					refr = 1;
				}
			} else 
				mbeep();
	}

	if (m->mopt & MC_SCROLL && scroll_sel) {
		while (m->cursel >= m->topline + m->h -1 )
			m->topline = MIN(m->topline+m->h-1,
					 m->numopts+hasexit-m->h+1);
		while (m->cursel < m->topline)
			m->topline = MAX(0,m->topline-m->h+1);
	}

	if (refr) {
		post_menu (m);
		wrefresh (m->mw);
	}
}

int
menu_init (void)
{

	if (__menu_init)
		return 0;

	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 = (menudesc *) malloc(sizeof(menudesc)*num_menus);
	if (menus == NULL)
		return 2;
	(void) memset ((void *)menus, 0, sizeof(menudesc)*num_menus);
	(void) memcpy ((void *)menus, (void *)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)
{
	int sel = 0;
	int req, done;
	int last_num;

	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)();
		post_menu (m);
		wrefresh (m->mw);

		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) {
			if (m->opts[sel].opt_flags & OPT_ENDWIN) {
				endwin();
				__m_endwin = 1;
			}
			if (m->opts[sel].opt_action)
				done = (*m->opts[sel].opt_action)(m);
			if (m->opts[sel].opt_menu != -1) {
				if (m->opts[sel].opt_flags & OPT_SUB)
					process_menu (m->opts[sel].opt_menu);
				else
					num = m->opts[sel].opt_menu;
			}

                        if (m->opts[sel].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. */

/* local prototypes */
static int double_menus (void);

static int 
double_menus (void)
{
	menudesc *temp;

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