/*
 * LEVEE, or Captain Video;  A vi clone
 *
 * Copyright (c) 1982-2007 David L Parsons
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, without or
 * without modification, are permitted provided that the above
 * copyright notice and this paragraph are duplicated in all such
 * forms and that any documentation, advertising materials, and
 * other materials related to such distribution and use acknowledge
 * that the software was developed by David L Parsons (orc@pell.chi.il.us).
 * My name may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 * THIS SOFTWARE IS PROVIDED AS IS'' AND WITHOUT ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
 * WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE.
 */

#if TERMCAP_EMULATION
/*
 * Termcap handlers
 *
 * Routines included:
 *   tc_init() -- set up all the terminal stuff levee will need.
 *  *xtract() -- get a field out of the termcap entry.
 *  *parseit() -- parse a termcap field.
 *   tgoto()   -- put a gotoXY string into a buffer.
 *  * -> internal routine.
 */

#if OS_RMX | OS_DOS		/* default to ANSI.SYS termcap */
char termcap[200] = "Ansi subset:CM=\033[%d;%dH,Y,1,1:\
CE=\033[K:CL=\033[H\033[J:LINES=24:COLS=79:HO=\033[H:FkL=\033:\
CurR=C:CurL=D:CurU=A:CurD=B";
#endif

char *
parseit(ptr,savearea)
/* parse a termcap field */
char *ptr;
char **savearea;
{
    char *p = *savearea;
    char *op = *savearea;
    int tmp;

    while (*ptr && *ptr != ':') {
	if (*ptr == '\\' && ptr[1]) {
	    ++ptr;
	    switch (*ptr) {
	      case 'E':
		*p++ = '\033';
		break;
	      case '0': case '1': case '2': case '3': case '4':
	      case '5': case '6': case '7': case '8': case '9':
		  tmp = 0;
		  while (*ptr >= '0' && *ptr <= '9')
		      tmp = (tmp*8)+(*ptr++ - '0');
		  *p++ = tmp;
		  --ptr;
	      default:
		  *p++ = *ptr;
	    }
	}
	else *p++ = *ptr;
	++ptr;
    }
    *p++ = 0;
    *savearea = p;
    return op;
} /* parseit */

char *
xtract(ptr,name,savearea)
/* get something from the termcap
 *
 * arguments: tcentry -- the termcap entry
 *            what    -- the field we want to get (NULL means first field)
 *            savearea-- pointer to static buffer for parsed fields.
 */
char *ptr;
char name[];
char **savearea;
{
    int size;

    if (!ptr)
	return NULL;

    if (!name)	/* return first field of entry -- terminal name? */
	return parseit(ptr,savearea);

    size = strlen(name);
    /*
     * always skip the first (terminal name) field
     */
    while (*ptr) {
	while (*ptr && *ptr != ':') {
	    if (*ptr == '\\')
		ptr++;
	    ptr++;
	}
	if (*ptr)
	    ptr++;
	if (*ptr && strncmp(name,ptr,size) == 0 && ptr[size] == '=')
	    return parseit(&ptr[1+size],savearea);
	puts("\r");
    }
    return NULL;
} /* xtract */

char
charext(tc,what,savearea)
/* get a character field from the termcap */
char *tc, *what, **savearea;
{
    char *p = xtract(tc,what,savearea);
    if (p)
	return *p;
    return 0;
} /* charext */

/* internal variables just for termcap */
static int _Xfirst, _xpad, _ypad;

void
tc_init()
/* get the termcap stuff and go berserk parsing it */
/* if anything horrid goes wrong, levee will crash */
{
#if OS_RMX
    char *p = termcap;
#else
    char *getenv();
    char *p = getenv("TERMCAP");
#endif
    char *lp, *ptr;

#if OS_DOS
    if (!p)
	p = termcap;
#endif
#if !(OS_RMX|OS_DOS)
    if (!p) {
	puts("lv: no termcap\n");
	exit(1);
    }
#endif
    lp = Malloc(strlen(p)+1);
    if (!lp) {
	puts("lv: out of memory\n");
	exit(1);
    }

    TERMNAME = xtract(p,NULL,&lp);
    CM   = xtract(p,"CM",&lp);
    HO   = xtract(p,"HO",&lp);
    UP   = xtract(p,"UP",&lp);
    CE   = xtract(p,"CE",&lp);
    CL   = xtract(p,"CL",&lp);
    BELL = xtract(p,"BELL",&lp);
    if (!BELL)
	BELL = "\007";
    OL   = xtract(p,"OL",&lp);
    UpS  = xtract(p,"UpS",&lp);
    CURon= xtract(p,"CURon",&lp);
    CURoff=xtract(p,"CURoff",&lp);

    FkL  = charext(p,"FkL",&lp);
    CurRT= charext(p,"CurR",&lp);
    CurLT= charext(p,"CurL",&lp);
    CurUP= charext(p,"CurU",&lp);
    CurDN= charext(p,"CurD",&lp);

    canUPSCROLL = (UpS != NULL);
    CA = (CM != NULL);

    if ((LINES=atoi(ptr=xtract(p,"LINES",&lp))) <= 0) {
	puts("lv: bad termcap");
	exit(1);
    }
    dofscroll = LINES/2;
    if ((COLS=atoi(ptr=xtract(p,"COLS",&lp))-1) <= 0 || COLS >= MAXCOLS) {
	puts("lv: bad termcap");
	exit(1);
    }

    _ypad = _xpad = 0;
    _Xfirst = 1;

    p = CM;

    while (*p && *p != ',')
	p++;
    if (!*p)
	return;
    *p++ = 0;
    if (*p != ',')
	_Xfirst = (*p++ == 'X');
    if (!*p)
	return;
    ++p;
    while (*p && *p != ',')
	_xpad = (_xpad*10) + (*p++ - '0');
    if (!*p)
	return;
    ++p;
    while (*p)
	_ypad = (_ypad*10) + (*p++ - '0');
}

#define tgoto(s,y,x)	(_Xfirst?sprintf(s,CM,x+_xpad,y+_ypad):\
				sprintf(s,CM,y+_ypad,x+_xpad))
#else

#include <stdlib.h>
#include <termcap.h>
#include <string.h>
#include <sys/ioctl.h>

void
tc_init()
/* read in the termcap entry for this terminal.
 */
{
    static char tcbuf[2048+1024];
    char *bufp;
    char *term = getenv("TERM");

    if (( term ? tgetent(tcbuf, term) : 0) != 0) {
	TERMNAME = term;
	bufp = tcbuf + 2048;
	CM = tgetstr("cm", &bufp);
	UP = tgetstr("up", &bufp);
	HO = tgetstr("ho", &bufp);
	if (!HO) {
	    char *goto0 = tgoto(CM, 0, 0);

	    if (goto0)
		HO = strdup(goto0);
	}

	CL = tgetstr("cl", &bufp);
	CE = tgetstr("ce", &bufp);
	BELL = tgetstr("vb", &bufp);
	if (!BELL)
	    BELL = "\007";
	OL = tgetstr("al", &bufp);
	UpS = tgetstr("sr", &bufp);
	CURon = tgetstr("ve", &bufp);
	CURoff = tgetstr("vi", &bufp);

	LINES = tgetnum("li");
	COLS  = tgetnum("co");

	/* don't trust li & co, because we might actually
	 * be on a console or gui instead of the tinned
	 * tty that termcap expects
	 */
#if defined(TIOCGSIZE)
	{   struct ttysize tty;
	    if (ioctl(0, TIOCGSIZE, &tty) == 0) {
		if (tty.ts_lines) LINES=tty.ts_lines;
		if (tty.ts_cols)  COLS=tty.ts_cols;
	    }
	}
#elif defined(TIOCGWINSZ)
	{   struct winsize tty;
	    if (ioctl(0, TIOCGWINSZ, &tty) == 0) {
		if (tty.ws_row) LINES=tty.ws_row;
		if (tty.ws_col) COLS=tty.ws_col;
	    }
	}
#endif

	dofscroll = LINES/2;

	/* set cursor movement keys to zero for now */
	FkL = CurRT = CurLT = CurUP = CurDN = EOF;

	canUPSCROLL = (UpS != NULL);
	CA = (CM != NULL);
    }
}
#endif