/*
   =============================================================================
	delnote.c -- MIDAS-VII note deletion
	Version 16 -- 1988-10-27 -- D.N. Lynx Crowe
   =============================================================================
*/

#include "ram.h"

#define	TO_LFT		(TO_BAK + 1)

/*
   =============================================================================
	delnote() -- delete a note
   =============================================================================
*/

int16_t delnote(void)
{
	register struct n_entry *bp, *cp, *ep;
	register int32_t t_left;
	register int16_t tnote, grp;
	register int16_t runtag, scantag;
	int16_t disptag;

	disptag = FALSE;	/* nothing changed yet */

	if (NOT recsw)			/* must be in record mode */
		return(FAILURE);

	/* convert cursor position to note number and time */

	if (pix2mid())
		goto notnote;

	++cflag;
	tnote   = cnote;
	t_left  = t_cur - TO_LFT;
	cp      = (struct n_entry *)frfind(ctime, 0);


	while (cflag--) {	/* handle both naturals and accidentals */

		for (grp = 0; grp < 12; grp++) {	/* for each group ... */

			if ((grpstat[grp] EQ 0) OR	/* ... enabled and ... */
			    (grpmode[grp] NE 2))	/* ... in record mode: */
				continue;

			runtag = TRUE;
			bp = cp;		/* start at cursor */

			while (runtag) {	/* scan left from cursor until: */

				if ((bp->e_time LT t_left) OR
				    (bp->e_type EQ EV_SCORE)) {	/* left edge */

					/* done -- nothing to delete */

					runtag = FALSE;
					continue;

				} else if ((bp->e_type EQ EV_NEND) AND
				    (bp->e_note EQ tnote) AND
				    (bp->e_group EQ grp)) {	/* note end */

					/* done -- overlap */

					runtag = FALSE;
					continue;

				} else if ((bp->e_type EQ EV_NBEG) AND
				    (bp->e_note EQ tnote) AND
				    (bp->e_group EQ grp)) {	/* note begin */

					/* possible deletion */

					/* scan right from note begin until: */

					ep = (struct n_entry *)bp->e_fwd;
					scantag = TRUE;

					while (scantag) {

						/* note begin -- done -- overlap */

						if ((ep->e_type EQ EV_NBEG) AND
						    (ep->e_note EQ tnote) AND
						    (ep->e_group EQ grp)) {

								scantag = FALSE;
								runtag  = FALSE;
								continue;

						} else if ((ep->e_type EQ EV_NEND) AND
						    (ep->e_note EQ tnote) AND
						    (ep->e_group EQ grp)) {

							/* note end */

							/* delete note end */

							if (cp EQ ep)
								cp = (struct n_entry *)cp->e_bak;

							if (p_ctr EQ (struct s_entry *)ep)
								p_ctr = p_ctr->e_bak;

							if (p_bak EQ (struct s_entry *)ep)
								p_bak = p_bak->e_bak;

							if (p_fwd EQ (struct s_entry *)ep)
								p_fwd = p_fwd->e_bak;

							if (p_cur EQ (struct s_entry *)ep)
								p_cur = p_cur->e_bak;

							e_del(e_rmv((struct s_entry *)ep));

							/* delete note begin */

							if (cp EQ bp)
								cp = (struct n_entry *)cp->e_bak;

							if (p_ctr EQ (struct s_entry *)bp)
								p_ctr = p_ctr->e_bak;

							if (p_bak EQ (struct s_entry *)bp)
								p_bak = p_bak->e_bak;

							if (p_fwd EQ (struct s_entry *)bp)
								p_fwd = p_fwd->e_bak;

							if (p_cur EQ (struct s_entry *)bp)
								p_cur = p_cur->e_bak;

							e_del(e_rmv((struct s_entry *)bp));

							disptag = TRUE;
							runtag  = FALSE;
							scantag = FALSE;
							continue;

						} else if (ep->e_type EQ EV_FINI) {

							/* score end */

							/* delete note begin */

							if (cp EQ bp)
								cp = (struct n_entry *)cp->e_bak;

							if (p_ctr EQ (struct s_entry *)bp)
								p_ctr = p_ctr->e_bak;

							if (p_bak EQ (struct s_entry *)bp)
								p_bak = p_bak->e_bak;

							if (p_fwd EQ (struct s_entry *)bp)
								p_fwd = p_fwd->e_bak;

							if (p_cur EQ (struct s_entry *)bp)
								p_cur = p_cur->e_bak;

							e_del(e_rmv((struct s_entry *)bp));

							disptag = TRUE;
							runtag  = FALSE;
							scantag = FALSE;
							continue;
						}

						/* scan right */

						ep = (struct n_entry *)ep->e_fwd;

					}	/* end while (scantag) */

				}	/* end if */

				/* scan left */

				bp = (struct n_entry *)bp->e_bak;

			}	/* end while (runtag) */

		}	/* end for (grp) */

		/* handle accidentals */

		if (ac_code EQ N_SHARP)
			++tnote;	/* treat accidentals as sharps */
		else
			--tnote;	/* treat accidentals as flats */

	}	/* end while (cflag) */

notnote:	/* jumped to if pix2mid() returned FAILURE (not on a note) */

	/* check for a bar marker delete operation */

	if (NOT disptag) {	/* if no notes were deleted, try for a bar */

		if (ctime < 0L)	/* time has to be good */
			return(FAILURE);

		/* search current time for a bar marker - delete any found */

		ep = (struct n_entry *)ep_adj(p_cur, 1, ctime);

		while (ctime EQ ep->e_time) {

			bp = (struct n_entry *)ep->e_fwd;

			if (EV_BAR EQ ep->e_type) {

				if (ep EQ (struct n_entry *)p_bak)
					p_bak = p_bak->e_bak;

				if (ep EQ (struct n_entry *)p_ctr)
					p_ctr = p_ctr->e_bak;

				if (ep EQ (struct n_entry *)p_cur)
					p_cur = p_cur->e_bak;

				if (ep EQ (struct n_entry *)p_fwd)
					p_fwd = p_fwd->e_bak;

				e_del(e_rmv((struct s_entry *)ep));
				disptag = TRUE;
			}

			ep = bp;
		}
	}

	if (disptag)
		sc_refr(t_cur);

	return(disptag ? SUCCESS : FAILURE);
}