/************************************************************************
 * This program is Copyright (C) 1986-1996 by Jonathan Payne.  JOVE is  *
 * provided to you without charge, and with no warranty.  You may give  *
 * away copies of JOVE, including sources, provided that this notice is *
 * included in all the files.                                           *
 ************************************************************************/

#include "jove.h"
#include "fp.h"
#include "jctype.h"
#include "chars.h"
#include "commands.h"
#include "disp.h"
#include "re.h"
#include "ask.h"
#include "extend.h"
#include "fmt.h"
#include "insert.h"
#include "move.h"
#include "sysprocs.h"
#include "proc.h"
/* #include "util.h" */
#include "vars.h"

#ifdef SUBSHELL
# include <errno.h>
#endif

#ifdef MAC
# include "mac.h"
#endif

#ifdef MSDOS_PROCS
# include <process.h>
#endif

private void
	DefAutoExec proto((data_obj *(*proc) ptrproto((const char *))));

int	InJoverc = 0;

/* Auto execute code */

#define NEXECS	20

private struct AutoExec {
	char	*a_pattern;
	data_obj	*a_cmd;
	int	a_arg_state,
		a_arg_count;
} AutoExecs[NEXECS];	/* must be initialized by system to 0 */

private int	ExecIndex = 0;

/* Command auto-execute. */

void
CAutoExec()
{
	DefAutoExec(findcom);
}

/* Macro auto-execute. */

void
MAutoExec()
{
	DefAutoExec(findmac);
}

private void
DefAutoExec(proc)
data_obj	*(*proc) ptrproto((const char *));
{
	data_obj	*d = (*proc)(ProcFmt);
	char	*pattern;
	register struct AutoExec	*p;

	pattern = do_ask("\r\n", NULL_ASK_EXT, (char *) NULL, ": %f %s ", d->Name);
	for (p = AutoExecs; p != &AutoExecs[ExecIndex]; p++)
		if (p->a_cmd == d
		&& ((pattern == NULL || p->a_pattern == NULL)?
			(pattern == p->a_pattern) : (strcmp(pattern, p->a_pattern) == 0))
		&& p->a_arg_state == arg_state
		&& p->a_arg_count == arg_count)
			return;		/* eliminate duplicates */
	if (ExecIndex >= NEXECS)
		complain("Too many auto-executes, max %d.", NEXECS);
	p->a_pattern = copystr(pattern);
	p->a_cmd = d;
	p->a_arg_state = arg_state;
	p->a_arg_count = arg_count;
	ExecIndex += 1;
}

/* DoAutoExec: NEW and OLD are file names, and if NEW and OLD aren't the
   same kind of file (i.e., match the same pattern) or OLD is NULL and it
   matches, OR if the pattern is NULL (none was specified) then, we execute
   the command associated with that kind of file. */

void
DoAutoExec(new, old)
register char	*new,
		*old;
{
	register struct AutoExec	*p;

	for (p = AutoExecs; p != &AutoExecs[ExecIndex]; p++) {
		if (p->a_pattern == NULL
		|| ((new != NULL && LookingAt(p->a_pattern, new, 0))
		   && !(old != NULL && LookingAt(p->a_pattern, old, 0))))
		{
			arg_state = p->a_arg_state;
			arg_count = p->a_arg_count;
			ExecCmd(p->a_cmd);
			clr_arg_value();
		}
	}
}

ZXchar
addgetc()	/* NOTE: can return EOF */
{
	ZXchar	c;

	if (!InJoverc) {
		Asking = YES;
		AskingWidth = strlen(mesgbuf);
		c = getch();
		Asking = NO;
		add_mess("%p ", c);
	} else {
		c = getch();
		switch (c) {
		case '\n':
			c = EOF;	/* this isn't part of the sequence */
			break;
		case '\\':
		case '^':
			c = DecodePair(c, getch());
			break;
		}
	}
	return c;
}

void
Extend()
{
	ExecCmd(findcom(": "));
}

/* Read a positive integer from CP.  It must be in base BASE, and
   complains if it isn't.  If allints, all the characters
   in the string must be integers or we return NO (failure); otherwise
   we stop reading at the first nondigit and return YES (success). */

bool
chr_to_int(cp, base, allints, result)
register char	*cp;
int	base;
bool	allints;
register int	*result;
{
	register char	c;
	int	value = 0,
		sign;

	if ((c = *cp) == '-') {
		sign = -1;
		cp += 1;
	} else
		sign = 1;
	while ((c = *cp++) != '\0') {
		if (!jisdigit(c)) {
			if (allints)
				return NO;
			break;
		}
		c = c - '0';
		if (c >= base)
			complain("You must specify in base %d.", base);
		value = value * base + c;
	}
	*result = value * sign;
	return YES;
}

int
ask_int(def, prompt, base)
char	*def;
char	*prompt;
int	base;
{
	char	*val = ask(def, prompt);
	int	value;

	if (!chr_to_int(val, base, YES, &value))
		complain("That's not a number!");
	return value;
}

void
vpr_aux(vp, buf, size)
register const struct variable	*vp;
char	*buf;
size_t	size;
{
	switch (vp->v_flags & V_TYPEMASK) {
	case V_INT:
	case V_WHOLEX:
	case V_WHOLE:
	case V_NAT:
		swritef(buf, size, (vp->v_flags & V_FMODE)? "%03o" : "%d",
			*((int *) vp->v_value));
		break;

	case V_BOOL:
		swritef(buf, size, (*((int *) vp->v_value)) ? "on" : "off");
		break;

	case V_STRING:
	case V_FILENAME:
		swritef(buf, size, "%s", vp->v_value);
		break;

	case V_CHAR:
		swritef(buf, size, "%p", *((ZXchar *) vp->v_value));
		break;
	}
}

void
PrVar()
{
	struct variable	*vp = (struct variable *) findvar(ProcFmt);
	char	prbuf[MAXCOLS];

	vpr_aux(vp, prbuf, sizeof(prbuf));
	f_mess(": %f %s => %s", vp->Name, prbuf);
	stickymsg = YES;
}

void
vset_aux(vp, prompt)
const struct variable	*vp;
char	*prompt;
{
	switch (vp->v_flags & V_TYPEMASK) {
	case V_INT:
	case V_WHOLEX:
	case V_WHOLE:
	case V_NAT:
	    {
		char	def[30];
		static const int	lwbt[] = {
			~0,	/* V_INT -- I hope we are two's complement */
			-1,	/* V_WHOLEX */
			0,	/* V_WHOLE */
			1,	/* V_NAT */
			};
		int
			val,
			lwb = lwbt[(vp->v_flags & V_TYPEMASK) - V_INT];

		vpr_aux(vp, def, sizeof(def));
		val = ask_int(def, prompt, (vp->v_flags & V_FMODE)? 8 : 10);
		if (val < lwb)
			complain("[%s must not be less than %d]", vp->Name, lwb);
		*((int *) vp->v_value) = val;
		break;
	    }

	case V_BOOL:
	    {
		static char	*possible[/*bool*/] = {"off", "on", NULL };
		bool	*valp = (bool *) vp->v_value;
		int	newval = complete(possible, possible[!*valp], prompt,
			CASEIND | ALLOW_OLD | ALLOW_EMPTY);

		if (newval < 0)
			newval = !*valp;
		*valp = newval;
#ifdef MAC
		MarkVar(vp, -1, 0);	/* mark the menu item */
#endif
		s_mess("%s%s", prompt, possible[newval]);
		break;
	    }

	case V_FILENAME:
	    {
		char	fbuf[FILESIZE];

		strcpy((char *) vp->v_value,
			ask_file(prompt, (char *) vp->v_value, fbuf));
		break;
	    }

	case V_STRING:
	    {
		char	*str;

		/* Do_ask() so you can set string to "" if you so desire. */
		str = do_ask("\r\n", NULL_ASK_EXT, (char *) vp->v_value, prompt);
		if (str == NULL)
			str = NullStr;
		if (strlen(str) >= vp->v_size)
			complain("string too long");
		strcpy((char *) vp->v_value, str);
		break;
	    }

	case V_CHAR:
		s_mess(prompt);
		*((ZXchar *) vp->v_value) = addgetc();
		break;
	}

	if (vp->v_flags & V_MODELINE)
		UpdModLine = YES;
	if (vp->v_flags & V_CLRSCREEN)
		ClAndRedraw();
	if (vp->v_flags & V_TTY_RESET)
		tty_adjust();
#ifdef UNIX
	if (vp->v_flags & V_UPDFREQ)
		SetClockAlarm(YES);
#endif
#if defined(USE_CTYPE) && !defined(NO_SETLOCALE)
	if (vp->v_flags & V_LOCALE) {
		locale_adjust();
		ClAndRedraw();
	}
#endif
}

void
SetVar()
{
	struct variable	*vp = (struct variable *) findvar(ProcFmt);
	char	prompt[128];

	swritef(prompt, sizeof(prompt), ": %f %s ", vp->Name);
	vset_aux(vp, prompt);
}

/* complete: buffer/command/keymap/macro/variable name completion.
 *
 * possible: an array of strings
 * prompt: the prompt to use
 * flags: a set of flags:
 *   CASEIND: ignore case
 *   ALLOW_OLD: allow answer listed in possible
 *   ALLOW_NEW: allow answer not listed in possible
 *   ALLOW_EMPTY: allow empty answer
 *
 * complete returns an index into possible, or -1 if there is no
 * right answer there, in which case what the user typed is in Minibuf.
 *
 * aux_complete is called by real_ask, on behalf of complete, to handle:
 *
 * ?        Typeout possible completions (does not change the answer)
 *
 * TAB      Extend answer as much as possible (this might actually
 *          involve shrinking the answer until it is the prefix of
 *          at least one Possible; if so, error).
 *
 * SP       If answer is complete (i.e. matches a whole entry in Possible),
 *          accept it.  Otherwise, extend answer as much as possible;
 *          if the result is unique, and we didn't shrink the answer,
 *          accept it.
 *
 * CR or NL If ALLOW_NEW and answer non-empty: accept the answer.
 *          If ALLOW_EMPTY and answer empty: accept the answer.
 *          If ALLOW_OLD and answer is complete: accept it.
 *          If ALLOW_OLD and answer is prefix of a unique Possible: accept that Possible.
 *          If ALLOW_INDEX and answer is a numeral that is a legitimate
 *          index into possible, accept as that possible.
 *          Otherwise: error
 *
 * If we are InJoverc, we cannot be interactive, so ? is forbidden
 * and all the others are treated as CR; an error is fatal.
 *
 * The following file-static variables smuggle values from complete
 * to aux_complete and vice versa, behind the back of do_ask etc.
 * This could be nicer if C supported nested procedures (closures);
 * perhaps we should simulate them.
 */

private char	**Possible;	/* possible arg of complete */
private int
	comp_flags,	/* flags arg of complete */
	comp_value;	/* return value for complete; set by aux_complete */

private bool aux_complete proto((ZXchar c));	/* needed to comfort dumb MS Visual C */

private bool
aux_complete(c)
ZXchar	c;
{
	if (comp_flags & CASEIND) {
		char	lc;
		char	*lp;

		for (lp = linebuf; (lc = *lp) != '\0'; lp++)
			*lp = CharDowncase(lc);
	}
	if (c == '?') {
		int	i;
		size_t	len = strlen(linebuf);

		if (InJoverc)
			complain("[invalid `?']");
		/* kludge: in case we're using UseBuffers, in which case
		   linebuf gets written all over (but restored by TOstop/TOabort) */
		strcpy(Minibuf, linebuf);
		TOstart("Completion");	/* for now ... */
		for (i = 0; Possible[i] != NULL && !TOabort; i++) {
			if ((comp_flags & ALLOW_INDEX) && len == 0)
				Typeout("%2d %s", i+1, Possible[i]);
			else if (strncmp(Possible[i], Minibuf, len) == 0)
				Typeout("%s", Possible[i]);
		}

		TOstop();
	} else {
		/* let's do some completion! */
		int
			i,
			numeral,
			len = strlen(linebuf),
			minmatch = 1000,	/* init with dummy to placate picky compilers */
			maxmatch = 0,
			numfound = 0,
			lastmatch = -1;	/* init with dummy to placate picky compilers */

		if (InJoverc || c == '\n')
			c = '\r';	/* NL is synonym for CR; InJoverc, all are treated as CR */
		for (i = 0; Possible[i] != NULL; i++) {
			int	this_len = *Possible[i] == *linebuf
				? numcomp(Possible[i], linebuf) : 0;

			if (maxmatch < this_len)
				maxmatch = this_len;
			if (this_len >= len) {
				if (Possible[i][len] == '\0' && c != '\t') {
					/* an exact match */
					if (comp_flags & ALLOW_OLD) {
						comp_value = i;	/* good: done */
						return NO;
					} else {
						if (InJoverc)
							complain("[%s already exists]");
						add_mess(" [already exists]");
						SitFor(7);
						return YES;
					}
				}
				minmatch = numfound == 0
					? strlen(Possible[i])
					: min(minmatch, numcomp(Possible[lastmatch], Possible[i]));
				numfound += 1;
				lastmatch = i;
			}
		}

		if (c == '\r' && len > 0
		&& (comp_flags & ALLOW_INDEX)
		&& chr_to_int(linebuf, 10, YES, &numeral)
		&& 0 < numeral && numeral <= i
		) {
			comp_value = numeral - 1;	/* accept as an index into possible */
			return NO;
		}

		if (c == '\r' && (comp_flags & (len == 0? ALLOW_EMPTY : ALLOW_NEW))) {
			comp_value = -1;	/* accept as new value (perhaps empty) */
			return NO;
		}
		if (numfound == 1 && c != '\t' && (comp_flags & ALLOW_OLD)) {
			comp_value = lastmatch;
			return NO;
		}
		if (InJoverc)
			complain("[\"%s\" %s]", linebuf,
				numfound == 0? "unknown" : "ambiguous");
		if (numfound == 0) {
			/* Unknown: either not ALLOW_NEW (bad) or not CR (not good enough) */
			add_mess(" [unknown]");
			SitFor(7);
			if (maxmatch < len && (comp_flags & ALLOW_NEW) == 0) {
				linebuf[maxmatch] = '\0';
				Eol();
			}
		} else {
			/* Ambiguous (or unique, but TAB): extend as much as
			 * possible without precluding any of the ambiguous matches.
			 * Explain if we were expected to be done (CR)
			 * or if we made no progress.
			 */
			null_ncpy(linebuf, Possible[lastmatch], (size_t) minmatch);
			Eol();
			if (c == '\r' || minmatch == len) {
				add_mess(numfound == 1? " [complete]" : " [ambiguous]");
				SitFor(7);
			}
		}
	}
	return YES;
}

int
complete(possible, def, prompt, flags)
register char	*possible[];
const char	*def;
const char	*prompt;
int	flags;
{
	/* protect static "Possible" etc. from being overwritten due to recursion */
	if (InRealAsk)
		complain((char *) NULL);

	Possible = possible;
	comp_flags = flags;
	(void) do_ask("\r\n \t?", aux_complete, def, prompt);
	return comp_value;
}

void
Source()
{
	char
		fnamebuf[FILESIZE];
	bool	silence = is_an_arg();

	swritef(fnamebuf, sizeof(fnamebuf),
#ifdef MSFILESYSTEM
		"%s/jove.rc",
#else
		"%s/.joverc",
#endif
		HomeDir);
	(void) ask_file((char *)NULL, fnamebuf, fnamebuf);
	if (!joverc(fnamebuf) && !silence) {
		message(IOerr("read", fnamebuf));
		complain((char *)NULL);
	}
}

void
BufPos()
{
	register LinePtr	lp = curbuf->b_first;
	register int
		i,
		dotline = 0;	/* avoid uninitialized complaint from gcc -W */
	long	dotchar = 0;	/* avoid uninitialized complaint from gcc -W */
	long	nchars;

	for (i = nchars = 0; lp != NULL; i++, lp = lp->l_next) {
		if (lp == curline) {
			dotchar = nchars + curchar;
			dotline = i + 1;
		}
		nchars += length(lp) + (lp->l_next != NULL);	/* include the NL */
	}

	f_mess("[\"%s\" line %d/%d, char %D/%D (%d%%), cursor = %d/%d]",
	       filename(curbuf), dotline, i, dotchar, nchars,
	       (nchars == 0) ? 100 : (int) (((long) dotchar * 100) / nchars),
	       calc_pos(linebuf, curchar),
	       calc_pos(linebuf, (int)strlen(linebuf)));
	stickymsg = YES;
}

#ifdef SUBSHELL

private bool
do_if(cmd)
char	*cmd;
{
	char	*args[12];

	/* Parse cmd into an argv.  Handle various quotes
	 * but not environment variable references.
	 */
	{
		char
			*ip = cmd,
			*op = cmd,
			**ap = args;

		for (;;) {
			while (jiswhite(*ip))
			    ip++;
			if (*ip == '\0')
				break;
			if (ap == &args[elemsof(args)])
				complain("Too many args for IF shell command");
			*ap++ = op;
			for (;;) {
				char
					c = *ip++,
					c2;

				switch (c) {
				case '\0':
					ip -= 1;
					/*FALLTHROUGH*/
				case ' ':
				case '\t':
					break;
				case '"':
				case '\'':
					while ((c2 = *ip++) != c) {
						switch (c2) {
						case '\0':
							complain("Unpaired quote in IF command");
							/*NOTREACHED*/
						case '\\':
							if (c == '"') {
								c2 = *ip++;
								if (c2 == '\0')
									complain("Misplaced \\ in IF command");
							}
							/*FALLTHROUGH*/
						default:
							*op++ = c2;
							break;
						}
					}
					continue;
				case '\\':
					c = *ip++;
					if (c == '\0')
						complain("Misplaced \\ in IF command");
					/*FALLTHROUGH*/
				default:
					*op++ = c;
					continue;
				}
				break;
			}
			*op++ = '\0';
		}
		*ap = NULL;
	}

	/* Exec the parsed command */
# ifdef UNIX
	{
		wait_status_t status;

		switch (ChildPid = fork()) {
		case -1:
			complain("[Fork failed for IF: %s]", strerror(errno));
			/*NOTREACHED*/

		case 0:
			close(0);	/*	we want reads to fail */
			/* close(1);	 but not writes or ioctl's */
			/* close(2); */
			(void) execvp(args[0], args);
			_exit(errno);
			/*NOTREACHED*/
		}
		dowait(&status);
		if (!WIFEXITED(status))
			complain("[no status returned from child in IF test]");
		if (WIFSIGNALED(status))
			complain("[IF test terminated by signal %d]", WTERMSIG(status));
		return WEXITSTATUS(status)==0;
	}
# else
#  ifdef MSDOS_PROCS
	{
		int	status;

		if ((status = spawnvp(0, args[0], args)) < 0)
			complain("[Spawn failed: IF]");
		return (status == 0);	/* 0 means successful */
	}
#  else /* !MSDOS_PROCS */
	I do not know how to do this
#  endif /* !MSDOS_PROCS */
# endif /* !UNIX */
}
#endif /* SUBSHELL */

private bool
cmdmatch(inp, verb, oppat)
char	*inp;
char	*verb;
char	*oppat;
{
	int	len = strlen(verb);

	if (caseeqn(inp, verb, (size_t)len) && LookingAt("[ \\t]\\|$", inp, len)) {
		if (!LookingAt(oppat, inp, len))
			complain("[malformed %s]", verb);
		return YES;
	}
	return NO;
}

bool
joverc(file)
char	*file;
{
	char	buf[LBSIZE],
		lbuf[LBSIZE];

	jmp_buf	savejmp;
	volatile int	lnum = 0;
	File	*volatile fp;
	volatile bool	eof = NO;
	volatile unsigned int	/* bitstrings */
			finger = 1,
			skipping = 0,
			inelse = 0;

	fp = open_file(file, buf, F_READ, NO);
	if (fp == NULL)
		return NO;

	/* Catch any errors, here, and do the right thing with them,
	   and then restore the error handle to whoever did a setjmp
	   last. */

	InJoverc += 1;
	push_env(savejmp);
	if (setjmp(mainjmp)) {
		Buffer	*savebuf = curbuf;

		SetBuf(do_select((Window *)NULL, "RC errors"));
		ins_str(sprint("%s:%d:%s", pr_name(file, YES), lnum, lbuf));
		ins_str(sprint("\t%s\n", mesgbuf));
		unmodify();
		SetBuf(savebuf);
		Asking = NO;
	}
	while (!eof) {
		/* This peculiar delayed EOF testing allows the last line to
		 * end without a NL.  We add NL later, so we leave room for it.
		 */
		eof = f_gets(fp, lbuf, sizeof(lbuf)-1);
		lnum += 1;
		Inputp = lbuf;
		while (jiswhite(*Inputp))
			Inputp += 1;	/* skip white space */
		if (*Inputp == '#' || *Inputp == '\0') {
			/* a comment */
#ifdef SUBSHELL
		} else if (cmdmatch(Inputp, "if", "[ \t]*\\(.*\\)$")) {
			char	cmd[128];

			finger <<= 1;
			if (finger == 0)
				complain("[`if' nested too deeply]");

			putmatch(1, cmd, sizeof cmd);
			if (skipping == 0 && !do_if(cmd))
				skipping |= finger;
#endif /* SUBSHELL */
#ifndef MAC	/* no environment in MacOS */
		} else if (cmdmatch(Inputp, "ifenv", "\\>[ \t]*\\<\\([^ \t][^ \t]*\\)\\>[ \t]\\(.*\\)$")) {
			finger <<= 1;
			if (finger == 0)
				complain("[`ifenv' nested too deeply]");
			if (skipping == 0) {
				char	envname[128],
					envpat[128],
					*envval;

				putmatch(1, envname, sizeof envname);
				putmatch(2, envpat, sizeof envpat);
				envval = getenv(envname);
				if (envval==NULL || !LookingAt(envpat, envval, 0))
					skipping |= finger;
			}
#endif
		} else if (cmdmatch(Inputp, "else", "[ \\t]*$")) {
			if (finger == 1 || (inelse & finger))
				complain("[Unexpected `else']");
			inelse |= finger;
			skipping ^= finger;
		} else if (cmdmatch(Inputp, "endif", "[ \\t]*$")) {
			if (finger == 1)
				complain("[Unexpected `endif']");
			inelse &= ~finger;
			skipping &= ~finger;
			finger >>= 1;
		} else if (skipping == 0) {
			(void) strcat(Inputp, "\n");
			for (;;) {
				ZXchar	c;

				cmd_sync();
				this_cmd = OTHER_CMD;

				if ((c = ZXC(*Inputp)) == '-' || jisdigit(c)) {
					LastKeyStruck = c;
					Inputp += 1;
					Digit();
				} else {
					Extend();
				}

				/* get any pending input hiding in the peek buffer */

				if ((c = peekchar) != EOF) {
					peekchar = EOF;
					if (Inputp != NULL && ZXRC(Inputp[-1]) == c)
						Inputp -= 1;
					else if (!jiswhite(c) && c != '\n' && c != '\0')
						complain("[junk at end of line]");
				}

				if (Inputp == NULL)
					break;
				while (jiswhite(*Inputp))
					Inputp += 1;	/* skip white space */
				if (*Inputp == '\0' || *Inputp == '\n')
					break;
				if (this_cmd != ARG_CMD)
					complain("[junk at end of line]");
			}
		}
	}

#ifdef SUBSHELL
	if (finger != 1) {
		finger = 1;
		complain("[Missing endif]");
	}
#endif
	f_close(fp);
	pop_env(savejmp);
	Inputp = NULL;
	Asking = NO;
	InJoverc -= 1;
	return YES;
}