static char rcsid[] = "$Id: cutbuf.c,v 1.1 1992/09/05 01:13:32 mike Exp $";

/* $Log: cutbuf.c,v $
 * Revision 1.1  1992/09/05  01:13:32  mike
 * Initial revision
 *
 */

/*
 * CUTBUF.C : handle cut buffer
 */

/* Copyright 1990, 1991, 1992 Craig Durland
 *   Distributed under the terms of the GNU General Public License.
 *   Distributed "as is", without warranties of any kind, but comments,
 *     suggestions and bug reports are welcome.
 */

#include "me2.h"

Bag *cut_buffer;	/* must be initialized very early! */

/*
 * Yank text back from the cut buffer. This is really easy.
 * Bound to "C-y".
 */
yank(f,n) int f,n;
{
  if (n < 0) return FALSE;
  while (n--) if (!insert_bag(cut_buffer)) return FALSE;
  return TRUE;
}

/* Cut line(s) of text.
 * If called without an argument, it cuts from dot to the end of the line,
 *   unless it is at the end of the line, where it cuts the newline.
 * If called with an argument:
 *   0:         Cut from the start of the line to dot.
 *   Positive:  Cut from dot forward over that number of newlines.
 *   Negative:  Cut backwards that number of newlines.
 * Bound to "C-k".
 * Notes:
 *   If n > number of lines left in the buffer, just cut those.  This means
 *     you can use a real big n to delete all text to the end of the buffer.
 *     This also fixes a problem for Mutt programs that got a region (that
 *     included the end-of-buffer) and tried to use cut-line to delete the
 *     region.
 *   Some of the end of buffer checking is pretty sloppy.  I can get away
 *     with this because ldelete() does good checking.  For example, if you
 *     try a big delete on the last line of the buffer, the code will roll
 *     around to the top of the buffer and get a big delete count.  Not a
 *     big deal but it might be slow.
 */
cut_line(f,n) int f,n;
{
  register int32 chunk;
  Line *nextp;

	/* Clear cut buffer if last wasn't a cut */
  if (!(lastflag & CFCUT)) clear_bag(cut_buffer);

  thisflag |= CFCUT;

  if (f == FALSE)
  {
    chunk = llength(the_dot->line) -the_dot->offset;
    if (chunk == 0) chunk = 1;
  }
  else
    if (n == 0) { chunk = the_dot->offset; the_dot->offset = 0; }
    else
      if (n > 0)
      {
        chunk = llength(the_dot->line) -the_dot->offset +1;
        nextp = lforw(the_dot->line);
        while (--n)
        {
          if (nextp == BUFFER_LAST_LINE(curbp)) break;
          chunk += llength(nextp) +1;
          nextp = lforw(nextp);
        }
      }
      else { mlwrite("neg cut"); return FALSE; }

  return ldelete(chunk,TRUE);
}