/*	$OpenBSD: random.c,v 1.4 2001/01/29 01:58:09 niklas Exp $	*/

/*
 *		Assorted commands.
 * This file contains the command processors for a large assortment of 
 * unrelated commands.  The only thing they have in common is that they 
 * are all command processors.
 */

#include "def.h"

/*
 * Display a bunch of useful information about the current location of dot. 
 * The character under the cursor (in octal), the current line, row, and 
 * column, and approximate position of the cursor in the file (as a 
 * percentage) is displayed.  The column position assumes an infinite 
 * position display; it does not truncate just because the screen does.
 * This is normally bound to "C-X =".
 */
/* ARGSUSED */
int
showcpos(f, n)
	int f, n;
{
	LINE	*clp;
	long	 nchar; 
	long	 cchar;
	int	 nline, row;
	int	 cline, cbyte;		/* Current line/char/byte */
	int	 ratio;

	/* collect the data */
	clp = lforw(curbp->b_linep);
	cchar = 0;
	cline = 0;
	cbyte = 0;
	nchar = 0;
	nline = 0;
	for (;;) {	
		/* count this line */
		++nline;
		if (clp == curwp->w_dotp) {
			/* mark line */
			cline = nline;
			cchar = nchar + curwp->w_doto;
			if (curwp->w_doto == llength(clp))
				cbyte = '\n';
			else
				cbyte = lgetc(clp, curwp->w_doto);
		}
		/* now count the chars */
		nchar += llength(clp);
		clp = lforw(clp);
		if (clp == curbp->b_linep)
			break;
		/* count the newline */
		nchar++;
	}
	/* determine row */
	row = curwp->w_toprow + 1;
	clp = curwp->w_linep;
	while (clp != curbp->b_linep && clp != curwp->w_dotp) {
		++row;
		clp = lforw(clp);
	}
	/* NOSTRICT */
	ratio = nchar ? (100L * cchar) / nchar : 100;
	ewprintf("Char: %c (0%o)  point=%ld(%d%%)  line=%d  row=%d  col=%d",
	    cbyte, cbyte, cchar, ratio, cline, row, getcolpos());
	return TRUE;
}

int
getcolpos()
{
	int	col, i, c;

	/* determine column */
	col = 1;

	for (i = 0; i < curwp->w_doto; ++i) {
		c = lgetc(curwp->w_dotp, i);
		if (c == '\t'
#ifdef NOTAB
		    && !(curbp->b_flag & BFNOTAB)
#endif /* NOTAB */
			) {
			col |= 0x07;
			++col;
		} else if (ISCTRL(c) != FALSE)
			++col;
		++col;
	}
	return col;
}

/*
 * Twiddle the two characters on either side of dot.  If dot is at the end 
 * of the line twiddle the two characters before it.  Return with an error 
 * if dot is at the beginning of line; it seems to be a bit pointless to 
 * make this work.  This fixes up a very common typo with a single stroke. 
 * Normally bound to "C-T".  This always works within a line, so "WFEDIT" 
 * is good enough.
 */
/* ARGSUSED */
int
twiddle(f, n)
	int f, n;
{
	LINE	*dotp;
	int	 doto, cr;

	dotp = curwp->w_dotp;
	doto = curwp->w_doto;
	if (doto == llength(dotp)) {
		if (--doto <= 0)
			return FALSE;
	} else {
		if (doto == 0)
			return FALSE;
		++curwp->w_doto;
	}
	cr = lgetc(dotp, doto--);
	lputc(dotp, doto + 1, lgetc(dotp, doto));
	lputc(dotp, doto, cr);
	lchange(WFEDIT);
	return TRUE;
}

/*
 * Open up some blank space.  The basic plan is to insert a bunch of 
 * newlines, and then back up over them.  Everything is done by the 
 * subcommand procerssors.  They even handle the looping.  Normally this 
 * is bound to "C-O".
 */
/* ARGSUSED */
int
openline(f, n)
	int f, n;
{
	int	i;
	int	s;

	if (n < 0)
		return FALSE;
	if (n == 0)
		return TRUE;

	/* insert newlines */
	i = n;
	do {
		s = lnewline();
	} while (s == TRUE && --i);

	/* then go back up overtop of them all */
	if (s == TRUE)
		s = backchar(f | FFRAND, n);
	return s;
}

/*
 * Insert a newline.  [following "feature" not present in current version of
 * Gnu, and now disabled here too] If you are at the end of the line and the
 * next line is a blank line, just move into the blank line.  This makes 
 * "C-O" and "C-X C-O" work nicely, and reduces the ammount of screen update 
 * that has to be done.  This would not be as critical if screen update were a 
 * lot more efficient.
 */
/* ARGSUSED */
int
newline(f, n)
	int f, n;
{
	LINE	*lp;
	int	 s;

	if (n < 0)
		return FALSE;

	while (n--) {
		lp = curwp->w_dotp;
#ifdef undef
		if (llength(lp) == curwp->w_doto
		    && lforw(lp) != curbp->b_linep
		    && llength(lforw(lp)) == 0) {
			if ((s = forwchar(FFRAND, 1)) != TRUE)
				return s;
		} else
#endif /* undef */
		if ((s = lnewline()) != TRUE)
			return s;
	}
	return TRUE;
}

/*
 * Delete blank lines around dot. What this command does depends if dot is
 * sitting on a blank line. If dot is sitting on a blank line, this command 
 * deletes all the blank lines above and below the current line. If it is 
 * sitting on a non blank line then it deletes all of the blank lines after 
 * the line. Normally this command is bound to "C-X C-O". Any argument is 
 * ignored.
 */
/* ARGSUSED */
int
deblank(f, n)
	int f, n;
{
	LINE	*lp1, *lp2;
	RSIZE	 nld;

	lp1 = curwp->w_dotp;
	while (llength(lp1) == 0 && (lp2 = lback(lp1)) != curbp->b_linep)
		lp1 = lp2;
	lp2 = lp1;
	nld = (RSIZE)0;
	while ((lp2 = lforw(lp2)) != curbp->b_linep && llength(lp2) == 0)
		++nld;
	if (nld == 0)
		return (TRUE);
	curwp->w_dotp = lforw(lp1);
	curwp->w_doto = 0;
	return ldelete((RSIZE)nld, KNONE);
}

/*
 * Delete any whitespace around dot, then insert a space.
 */
int
justone(f, n)
	int f, n;
{
	(VOID)delwhite(f, n);
	return linsert(1, ' ');
}

/*
 * Delete any whitespace around dot.
 */
/* ARGSUSED */
int
delwhite(f, n)
	int f, n;
{
	int	col, c, s;

	col = curwp->w_doto;

	while (((c = lgetc(curwp->w_dotp, col)) == ' ' || c == '\t')
	       && col < llength(curwp->w_dotp))
		++col;
	do {
		if (curwp->w_doto == 0) {
			s = FALSE;
			break;
		}
		if ((s = backchar(FFRAND, 1)) != TRUE)
			break;
	} while ((c = lgetc(curwp->w_dotp, curwp->w_doto)) == ' ' || c == '\t');

	if (s == TRUE)
		(VOID)forwchar(FFRAND, 1);
	(VOID)ldelete((RSIZE)(col - curwp->w_doto), KNONE);
	return TRUE;
}

/*
 * Insert a newline, then enough tabs and spaces to duplicate the indentation
 * of the previous line.  Assumes tabs are every eight characters.  Quite 
 * simple.  Figure out the indentation of the current line.  Insert a newline 
 * by calling the standard routine.  Insert the indentation by inserting the 
 * right number of tabs and spaces.  Return TRUE if all ok.  Return FALSE if 
 * one of the subcomands failed. Normally bound to "C-J".
 */
/* ARGSUSED */
int
indent(f, n)
	int f, n;
{
	int	nicol;
	int	c;
	int	i;

	if (n < 0)
		return (FALSE);

	while (n--) {
		nicol = 0;
		for (i = 0; i < llength(curwp->w_dotp); ++i) {
			c = lgetc(curwp->w_dotp, i);
			if (c != ' ' && c != '\t')
				break;
			if (c == '\t')
				nicol |= 0x07;
			++nicol;
		}
		if (lnewline() == FALSE || ((
#ifdef	NOTAB
		    curbp->b_flag & BFNOTAB) ? linsert(nicol, ' ') == FALSE : (
#endif /* NOTAB */
		    ((i = nicol / 8) != 0 && linsert(i, '\t') == FALSE) ||
		    ((i = nicol % 8) != 0 && linsert(i, ' ') == FALSE))))
			return FALSE;
	}
	return TRUE;
}

/*
 * Delete forward.  This is real easy, because the basic delete routine does
 * all of the work.  Watches for negative arguments, and does the right thing. 
 * If any argument is present, it kills rather than deletes, to prevent loss 
 * of text if typed with a big argument.  Normally bound to "C-D".
 */
/* ARGSUSED */
int
forwdel(f, n)
	int f, n;
{
	if (n < 0)
		return backdel(f | FFRAND, -n);

	/* really a kill */
	if (f & FFARG) {
		if ((lastflag & CFKILL) == 0)
			kdelete();
		thisflag |= CFKILL;
	}

	return ldelete((RSIZE) n, (f & FFARG) ? KFORW : KNONE);
}

/*
 * Delete backwards.  This is quite easy too, because it's all done with 
 * other functions.  Just move the cursor back, and delete forwards.  Like 
 * delete forward, this actually does a kill if presented with an argument.
 */
/* ARGSUSED */
int
backdel(f, n)
	int f, n;
{
	int	s;

	if (n < 0)
		return forwdel(f | FFRAND, -n);

	/* really a kill */
	if (f & FFARG) {
		if ((lastflag & CFKILL) == 0)
			kdelete();
		thisflag |= CFKILL;
	}
	if ((s = backchar(f | FFRAND, n)) == TRUE)
		s = ldelete((RSIZE)n, (f & FFARG) ? KFORW : KNONE);

	return s;
}

/*
 * Kill line.  If called without an argument, it kills from dot to the end 
 * of the line, unless it is at the end of the line, when it kills the 
 * newline.  If called with an argument of 0, it kills from the start of the 
 * line to dot.  If called with a positive argument, it kills from dot 
 * forward over that number of newlines.  If called with a negative argument 
 * it kills any text before dot on the current line, then it kills back 
 * abs(arg) lines.
 */
/* ARGSUSED */
int
killline(f, n)
	int f, n;
{
	LINE	*nextp;
	RSIZE	 chunk;
	int	 i, c;

	/* clear kill buffer if last wasn't a kill */
	if ((lastflag & CFKILL) == 0)
		kdelete();
	thisflag |= CFKILL;
	if (!(f & FFARG)) {
		for (i = curwp->w_doto; i < llength(curwp->w_dotp); ++i)
			if ((c = lgetc(curwp->w_dotp, i)) != ' ' && c != '\t')
				break;
		if (i == llength(curwp->w_dotp))
			chunk = llength(curwp->w_dotp) - curwp->w_doto + 1;
		else {
			chunk = llength(curwp->w_dotp) - curwp->w_doto;
			if (chunk == 0)
				chunk = 1;
		}
	} else if (n > 0) {
		chunk = llength(curwp->w_dotp) - curwp->w_doto + 1;
		nextp = lforw(curwp->w_dotp);
		i = n;
		while (--i) {
			if (nextp == curbp->b_linep)
				break;
			chunk += llength(nextp) + 1;
			nextp = lforw(nextp);
		}
	} else {
		/* n <= 0 */
		chunk = curwp->w_doto;
		curwp->w_doto = 0;
		i = n;
		while (i++) {
			if (lback(curwp->w_dotp) == curbp->b_linep)
				break;
			curwp->w_dotp = lback(curwp->w_dotp);
			curwp->w_flag |= WFMOVE;
			chunk += llength(curwp->w_dotp) + 1;
		}
	}
	/*
	 * KFORW here is a bug.  Should be KBACK/KFORW, but we need to
	 * rewrite the ldelete code (later)?
	 */
	return (ldelete(chunk, KFORW));
}

/*
 * Yank text back from the kill buffer.  This is really easy.  All of the work 
 * is done by the standard insert routines.  All you do is run the loop, and 
 * check for errors.  The blank lines are inserted with a call to "newline"
 * instead of a call to "lnewline" so that the magic stuff that happens when 
 * you type a carriage return also happens when a carriage return is yanked 
 * back from the kill buffer.  An attempt has been made to fix the cosmetic 
 * bug associated with a yank when dot is on the top line of the window 
 * (nothing moves, because all of the new text landed off screen).
 */
/* ARGSUSED */
int
yank(f, n)
	int f, n;
{
	LINE	*lp;
	int	 c, i, nline;

	if (n < 0)
		return FALSE;

	/* newline counting */
	nline = 0;

	while (n--) {
		/* mark around last yank */
		isetmark();
		i = 0;
		while ((c = kremove(i)) >= 0) {
			if (c == '\n') {
				if (newline(FFRAND, 1) == FALSE)
					return FALSE;
				++nline;
			} else {
				if (linsert(1, c) == FALSE)
					return FALSE;
			}
			++i;
		}
	}
	/* cosmetic adjustment */
	lp = curwp->w_linep;

	/* if offscreen insert */
	if (curwp->w_dotp == lp) {
		while (nline-- && lback(lp) != curbp->b_linep)
			lp = lback(lp);
		/* adjust framing */
		curwp->w_linep = lp;
		curwp->w_flag |= WFHARD;
	}
	return TRUE;
}

#ifdef	NOTAB
/* ARGSUSED */
int
space_to_tabstop(f, n)
	int f, n;
{
	if (n < 0)
		return FALSE;
	if (n == 0)
		return TRUE;
	return linsert((n << 3) - (curwp->w_doto & 7), ' ');
}
#endif /* NOTAB */