/*
 *	File commands.
 */

#include "def.h"

static char	*itos	__P((char *, unsigned int));

/*
 * Insert a file into the current buffer.  Real easy - just call the
 * insertfile routine with the file name.
 */
/* ARGSUSED */
int
fileinsert(f, n)
	int f, n;
{
	int	 s;
	char	 fname[NFILEN];

	s = eread("Insert file: ", fname, NFILEN, EFNEW | EFCR | EFFILE);
	if (s != TRUE)
		return (s);
	return insertfile(adjustname(fname), (char *)NULL, FALSE);
	/* don't set buffer name */
}

/*
 * Select a file for editing.  Look around to see if you can find the file 
 * in another buffer; if you can find it, just switch to the buffer.  If
 * you cannot find the file, create a new buffer, read in the text, and 
 * switch to the new buffer.
 */
/* ARGSUSED */
int
filevisit(f, n)
	int f, n;
{
	BUFFER	*bp;
	int	 s;
	char	 fname[NFILEN];
	char	*adjf;

	s = eread("Find file: ", fname, NFILEN, EFNEW | EFCR | EFFILE);
	if (s != TRUE)
		return s;
	adjf = adjustname(fname);
	if ((bp = findbuffer(adjf)) == NULL)
		return FALSE;
	curbp = bp;
	if (showbuffer(bp, curwp, WFHARD) != TRUE)
		return FALSE;
	if (bp->b_fname[0] == 0)
		return readin(adjf);
	return TRUE;
}

/*
 * Pop to a file in the other window.  Same as the last function, but uses
 * popbuf instead of showbuffer.
 */
/* ARGSUSED */
int
poptofile(f, n)
	int f, n;
{
	BUFFER	*bp;
	MGWIN	*wp;
	int	 s;
	char	 fname[NFILEN];
	char	*adjf;

	if ((s = eread("Find file in other window: ", fname, NFILEN,
		       EFNEW | EFCR | EFFILE)) != TRUE)
		return s;
	adjf = adjustname(fname);
	if ((bp = findbuffer(adjf)) == NULL)
		return FALSE;
	if ((wp = popbuf(bp)) == NULL)
		return FALSE;
	curbp = bp;
	curwp = wp;
	if (bp->b_fname[0] == 0)
		return readin(adjf);
	return TRUE;
}

/*
 * given a file name, either find the buffer it uses, or create a new
 * empty buffer to put it in.
 */
BUFFER *
findbuffer(fname)
	char *fname;
{
	BUFFER		*bp;
	char		 bname[NBUFN], *cp;
	unsigned int	 count = 1;

	for (bp = bheadp; bp != NULL; bp = bp->b_bufp) {
		if (fncmp(bp->b_fname, fname) == 0)
			return bp;
	}
	/* new buffer name */
	makename(bname, fname);
	cp = bname + strlen(bname);
	while (bfind(bname, FALSE) != NULL) {
		/* add "<count>" to the name */
		*cp = '<';
		(VOID)strcpy(itos(cp, ++count) + 1, ">");
	}
	return bfind(bname, TRUE);
}

/*
 * Put the decimal representation of num into a buffer.  Hacked to be
 * faster, smaller, and less general.
 */
static char *
itos(bufp, num)
	char		*bufp;
	unsigned int	 num;
{
	if (num >= 10) {
		bufp = itos(bufp, num / 10);
		num %= 10;
	}
	*++bufp = '0' + num;
	return bufp;
}

/*
 * Read the file "fname" into the current buffer.  Make all of the text 
 * in the buffer go away, after checking for unsaved changes.  This is 
 * called by the "read" command, the "visit" command, and the mainline 
 * (for "uemacs file").
 */
int
readin(fname)
	char *fname;
{
	MGWIN	*wp;
	int	 status;

	/* might be old */
	if (bclear(curbp) != TRUE)
		return TRUE;
	status = insertfile(fname, fname, TRUE);

	/* no change */
	curbp->b_flag &= ~BFCHG;
	for (wp = wheadp; wp != NULL; wp = wp->w_wndp) {
		if (wp->w_bufp == curbp) {
			wp->w_dotp = wp->w_linep = lforw(curbp->b_linep);
			wp->w_doto = 0;
			wp->w_markp = NULL;
			wp->w_marko = 0;
		}
	}
	return status;
}

/*
 * NB, getting file attributes is done here under control of a flag
 * rather than in readin, which would be cleaner.  I was concerned
 * that some operating system might require the file to be open
 * in order to get the information.  Similarly for writing.
 */

/*
 * Insert a file in the current buffer, after dot.  Set mark at the end of 
 * the text inserted; point at the beginning.  Return a standard status. 
 * Print a summary (lines read, error message) out as well.  If the BACKUP 
 * conditional is set, then this routine also does the read end of backup 
 * processing.  The BFBAK flag, if set in a buffer, says that a backup 
 * should be taken.  It is set when a file is read in, but not on a new 
 * file.  (You don't need to make a backup copy of nothing.)
 */
static char    *line = NULL;
static int      linesize = 0;

int
insertfile(fname, newname, needinfo)
	char *fname, *newname;
	int   needinfo;
{
	BUFFER	*bp;
	LINE	*lp1, *lp2;
	LINE	*olp;			/* line we started at */
	MGWIN	*wp;
	int	 nbytes, s, nline;
	int	 opos;			/* and offset into it */

	lp1 = NULL;

	if (line == NULL) {
		line = malloc(NLINE);
		linesize = NLINE;
	}

	/* cheap */
	bp = curbp;
	if (newname != (char *)NULL)
		(VOID)strcpy(bp->b_fname, newname);

	/* hard file open */
	if ((s = ffropen(fname, needinfo ? bp : (BUFFER *) NULL)) == FIOERR)
		goto out;
	if (s == FIOFNF) {
		/* file not found */
		if (newname != NULL)
			ewprintf("(New file)");
		else
			ewprintf("(File not found)");
		goto out;
	}
	opos = curwp->w_doto;

	/* open a new line, at point, and start inserting after it */
	(VOID)lnewline();
	olp = lback(curwp->w_dotp);
	if (olp == curbp->b_linep) {
		/* if at end of buffer, create a line to insert before */
		(VOID)lnewline();
		curwp->w_dotp = lback(curwp->w_dotp);
	}

	/* don't count fake lines at the end */
	nline = 0;
	while ((s = ffgetline(line, linesize, &nbytes)) != FIOERR) {
doneread:
		switch (s) {
		case FIOSUC:
			++nline;
			/* and continue */
		case FIOEOF:
			/* the last line of the file */
			if ((lp1 = lalloc(nbytes)) == NULL) {
				/* keep message on the display */
				s = FIOERR;
				goto endoffile;
			}
			bcopy(line, &ltext(lp1)[0], nbytes);
			lp2 = lback(curwp->w_dotp);
			lp2->l_fp = lp1;
			lp1->l_fp = curwp->w_dotp;
			lp1->l_bp = lp2;
			curwp->w_dotp->l_bp = lp1;
			if (s == FIOEOF)
				goto endoffile;
			break;
		case FIOLONG:{
				/* a line too long to fit in our buffer */
				char           *cp;
				int             newsize;

				newsize = linesize * 2;
				if (newsize < 0 ||
				    (cp = malloc((unsigned)newsize)) == NULL) {
					ewprintf("Could not allocate %d bytes",
					    newsize);
						s = FIOERR;
						goto endoffile;
				}
				bcopy(line, cp, linesize);
				free(line);
				line = cp;
				s = ffgetline(line + linesize, linesize, 
				    &nbytes);
				nbytes += linesize;
				linesize = newsize;
				if (s == FIOERR)
					goto endoffile;
				goto doneread;
			}
		default:
			ewprintf("Unknown code %d reading file", s);
			s = FIOERR;
			break;
		}
	}
endoffile:
	/* ignore errors */
	(VOID)ffclose((BUFFER *)NULL);
	/* don't zap an error */
	if (s == FIOEOF) {
		if (nline == 1)
			ewprintf("(Read 1 line)");
		else
			ewprintf("(Read %d lines)", nline);
	}
	/* set mark at the end of the text */
	curwp->w_dotp = curwp->w_markp = lback(curwp->w_dotp);
	curwp->w_marko = llength(curwp->w_markp);
	(VOID)ldelnewline();
	curwp->w_dotp = olp;
	curwp->w_doto = opos;
	if (olp == curbp->b_linep)
		curwp->w_dotp = lforw(olp);
#ifndef NO_BACKUP
	if (newname != NULL)
		bp->b_flag |= BFCHG | BFBAK;	/* Need a backup.	 */
	else
		bp->b_flag |= BFCHG;
#else /* !NO_BACKUP */
	bp->b_flag |= BFCHG;
#endif /* !NO_BACKUP */
	/*
	 * if the insert was at the end of buffer, set lp1 to the end of
	 * buffer line, and lp2 to the beginning of the newly inserted text.
	 * (Otherwise lp2 is set to NULL.)  This is used below to set
	 * pointers in other windows correctly if they are also at the end of
	 * buffer.
	 */
	lp1 = bp->b_linep;
	if (curwp->w_markp == lp1) {
		lp2 = curwp->w_dotp;
	} else {
		/* delete extraneous newline */
		(VOID)ldelnewline();
out:		lp2 = NULL;
	}
	for (wp = wheadp; wp != NULL; wp = wp->w_wndp) {
		if (wp->w_bufp == curbp) {
			wp->w_flag |= WFMODE | WFEDIT;
			if (wp != curwp && lp2 != NULL) {
				if (wp->w_dotp == lp1)
					wp->w_dotp = lp2;
				if (wp->w_markp == lp1)
					wp->w_markp = lp2;
				if (wp->w_linep == lp1)
					wp->w_linep = lp2;
			}
		}
	}
	/* return false if error */
	return s != FIOERR;
}

/*
 * Fabriacte a buffer name from a given filename.  This routing knows
 * about the syntax of file names on the target system.
 * BDC1		left scan delimiter.
 * BDC2		optional second left scan delimiter.
 * BDC3		optional right scan delimiter.
 */
VOID
makename(bname, fname)
	char *bname, *fname;
{
	char *cp1, *cp2;

	cp1 = &fname[0];
	while (*cp1 != 0)
		++cp1;

	/* insure at least 1 character */
	--cp1;
#ifdef BDC2
	while (cp1 != &fname[0] && cp1[-1] != BDC1 && cp1[-1] != BDC2)
		--cp1;
#else /* BDC2 */
	while (cp1 != &fname[0] && cp1[-1] != BDC1)
		--cp1;
#endif /* BDC2 */
	cp2 = &bname[0];

#ifdef BDC3
	while (cp2 != &bname[NBUFN - 1] && *cp1 != 0 && *cp1 != BDC3)
		*cp2++ = *cp1++;
#else /* BDC3 */
	while (cp2 != &bname[NBUFN - 1] && *cp1 != 0)
		*cp2++ = *cp1++;
#endif /* BDC3 */
	*cp2 = 0;
}

/*
 * Ask for a file name and write the contents of the current buffer to that 
 * file.  Update the remembered file name and clear the buffer changed flag. 
 * This handling of file names is different from the earlier versions and
 * is more compatable with Gosling EMACS than with ITS EMACS.
 */
/* ARGSUSED */
int
filewrite(f, n)
	int f, n;
{
	int	 s;
	char	 fname[NFILEN];
	char	*adjfname;

	if ((s = eread("Write file: ", fname, NFILEN,
		       EFNEW | EFCR | EFFILE)) != TRUE)
		return (s);
	adjfname = adjustname(fname);
	/* old attributes are no longer current */
	bzero(&curbp->b_fi, sizeof(curbp->b_fi));
	if ((s = writeout(curbp, adjfname)) == TRUE) {
		(VOID)strcpy(curbp->b_fname, adjfname);
#ifndef NO_BACKUP
		curbp->b_flag &= ~(BFBAK | BFCHG);
#else /* !NO_BACKUP */
		curbp->b_flag &= ~BFCHG;
#endif /* !NO_BACKUP */
		upmodes(curbp);
	}
	return s;
}

/*
 * Save the contents of the current buffer back into its associated file.
 */
#ifndef NO_BACKUP
#ifndef	MAKEBACKUP
#define	MAKEBACKUP TRUE
#endif /* !MAKEBACKUP */
static int      makebackup = MAKEBACKUP;
#endif /* !NO_BACKUP */

/* ARGSUSED */
int
filesave(f, n)
	int f, n;
{
	return buffsave(curbp);
}

/*
 * Save the contents of the buffer argument into its associated file.  Do 
 * nothing if there have been no changes (is this a bug, or a feature?). 
 * Error if there is no remembered file name. If this is the first write 
 * since the read or visit, then a backup copy of the file is made.
 * Allow user to select whether or not to make backup files by looking at 
 * the value of makebackup.
 */
int
buffsave(bp)
	BUFFER *bp;
{
	int	 s;

	/* return, no changes */
	if ((bp->b_flag & BFCHG) == 0) {
		ewprintf("(No changes need to be saved)");
		return TRUE;
	}

	/* must have a name */
	if (bp->b_fname[0] == '\0') {
		ewprintf("No file name");
		return (FALSE);
	}

#ifndef NO_BACKUP
	if (makebackup && (bp->b_flag & BFBAK)) {
		s = fbackupfile(bp->b_fname);
		/* hard error */
		if (s == ABORT)
			return FALSE;
		/* softer error */
		if (s == FALSE && 
		    (s = eyesno("Backup error, save anyway")) != TRUE)
			return s;
	}
#endif /* !NO_BACKUP */
	if ((s = writeout(bp, bp->b_fname)) == TRUE) {
#ifndef NO_BACKUP
		bp->b_flag &= ~(BFCHG | BFBAK);
#else /* !NO_BACKUP */
		bp->b_flag &= ~BFCHG;
#endif /* !NO_BACKUP */
		upmodes(bp);
	}
	return s;
}

#ifndef NO_BACKUP
/*
 * Since we don't have variables (we probably should) this is a command
 * processor for changing the value of the make backup flag.  If no argument
 * is given, sets makebackup to true, so backups are made.  If an argument is
 * given, no backup files are made when saving a new version of a file. Only
 * used when BACKUP is #defined.
 */
/* ARGSUSED */
int
makebkfile(f, n)
	int f, n;
{
	if (f & FFARG)
		makebackup = n > 0;
	else
		makebackup = !makebackup;
	ewprintf("Backup files %sabled", makebackup ? "en" : "dis");
	return TRUE;
}
#endif /* !NO_BACKUP */

/*
 * NB: bp is passed to both ffwopen and ffclose because some
 * attribute information may need to be updated at open time
 * and others after the close.  This is OS-dependent.  Note
 * that the ff routines are assumed to be able to tell whether
 * the attribute information has been set up in this buffer
 * or not.
 */

/*
 * This function performs the details of file writing; writing the file 
 * in buffer bp to file fn. Uses the file management routines in the 
 * "fileio.c" package. Most of the grief is checking of some sort.
 */
int
writeout(bp, fn)
	BUFFER *bp;
	char   *fn;
{
	int	 s;

	/* open writes message */
	if ((s = ffwopen(fn, bp)) != FIOSUC)
		return (FALSE);
	s = ffputbuf(bp);
	if (s == FIOSUC) {
		/* no write error */
		s = ffclose(bp);
		if (s == FIOSUC)
			ewprintf("Wrote %s", fn);
	} else
		/* ignore close error if it is a write error */
		(VOID)ffclose(bp);
	return s == FIOSUC;
}

/*
 * Tag all windows for bp (all windows if bp == NULL) as needing their
 * mode line updated.
 */
VOID
upmodes(bp)
	BUFFER *bp;
{
	MGWIN	*wp;

	for (wp = wheadp; wp != NULL; wp = wp->w_wndp)
		if (bp == NULL || curwp->w_bufp == bp)
			wp->w_flag |= WFMODE;
}