/**************************************************************************
 * This program is Copyright (C) 1986-2002 by Jonathan Payne.  JOVE is    *
 * provided by Jonathan and Jovehacks without charge and without          *
 * warranty.  You may copy, modify, and/or distribute JOVE, provided that *
 * this notice is included in all the source files and documentation.     *
 **************************************************************************/

#include "jove.h"
#include "fmt.h"
#include "marks.h"
#include "disp.h"

private Mark	*FreeMarksList = NULL;

#define RecycleMark(m)	{ \
	(m)->m_next = FreeMarksList; \
	FreeMarksList = (m); \
	(m)->m_line = NULL; /* DEBUG */ \
}

Mark *
MakeMark(line, column)
register LinePtr	line;
int	column;
{
	register Mark	*newmark;

	if ((newmark = FreeMarksList) != NULL)
		FreeMarksList = newmark->m_next;
	else
		newmark = (Mark *) emalloc(sizeof *newmark);
	MarkSet(newmark, line, column);
	newmark->m_big_delete = NO;
	newmark->m_next = curbuf->b_marks;
	curbuf->b_marks = newmark;
	return newmark;
}

void
flush_marks(b)
Buffer	*b;
{
	register Mark	*m,
			*next;

	for (m = b->b_marks; m != NULL; m = next) {
		next = m->m_next;
		RecycleMark(m)
	}
}

private void
DelBufMark(b, m)
Buffer	*b;
register Mark	*m;
{
	register Mark	*mp = b->b_marks;

	if (MarkHighlighting)
		makedirty(m->m_line);
	if (m == mp)
		b->b_marks = m->m_next;
	else {
		while (mp != NULL && mp->m_next != m)
			mp = mp->m_next;
		if (mp == NULL)
			complain("Unknown mark!");
		mp->m_next = m->m_next;
	}
	RecycleMark(m);
}

void
DelMark(m)
register Mark	*m;
{
	DelBufMark(curbuf, m);
}

/* AllMarkReset is used when a buffer is completely replaced.
 * We delete the marks in the mark ring, but we cannot find
 * the references to other marks, so those we make point
 * to the start of the buffer.
 */

void
AllMarkReset(b, line)
Buffer	*b;
register LinePtr	line;
{
	{
		register Mark	**mpp;

		for (mpp = &b->b_markring[0]; mpp != &b->b_markring[NMARKS]; mpp++) {
			if (*mpp != NULL) {
				DelBufMark(b, *mpp);
				*mpp = NULL;
			}
		}
		b->b_themark = 0;
	}

	{
		register Mark	*mp;

		for (mp = b->b_marks; mp != NULL; mp = mp->m_next)
			MarkSet(mp, line, 0);
	}
}

void
MarkSet(m, line, column)
Mark	*m;
LinePtr	line;
int	column;
{
	m->m_line = line;
	m->m_char = column;
	m->m_big_delete = NO;
	if (MarkHighlighting)
		makedirty(line);
}

void
PopMark()
{
	int	pmark;

	if (curmark == NULL)
		return;

	ExchPtMark();
	pmark = curbuf->b_themark;
	do {
		if (--pmark < 0)
			pmark = NMARKS - 1;
	} while (curbuf->b_markring[pmark] == NULL);
	curbuf->b_themark = pmark;
	if (MarkHighlighting)
		makedirty(curmark->m_line);
}

void
SetMark()
{
	if (is_an_arg())
		PopMark();
	else
		set_mark();
}

void
set_mark()
{
	do_set_mark(curline, curchar);
}

void
do_set_mark(l, c)
LinePtr	l;
int	c;
{
	Mark	**mr = curbuf->b_markring;
	int	tm = curbuf->b_themark;

	if (mr[tm] != NULL) {
		if (MarkHighlighting)
			makedirty(mr[tm]->m_line);
		curbuf->b_themark = tm = (tm + 1) % NMARKS;
		if (mr[NMARKS-1] == NULL) {
			/* there is an empty slot: make sure one is here */
			int	i;

			for (i = NMARKS-1; i != tm; i--)
				mr[i] = mr[i-1];
			mr[i] = NULL;
		}
	}
	if (mr[tm] == NULL)
		mr[tm] = MakeMark(l, c);
	else
		MarkSet(mr[tm], l, c);
	s_mess("[Point pushed]");
}

/* Move point to Mark */

void
ToMark(m)
Mark	*m;
{
	int	len;

	if (m == NULL)
		return;

	DotTo(m->m_line, m->m_char);
	if (curchar > (len = length(curline)))
		curchar = len;
}

Mark *
CurMark()
{
	if (curmark == NULL)
		complain("No mark.");
	return curmark;
}

void
ExchPtMark()
{
	LinePtr	mline;
	int	mchar;
	Mark	*m = CurMark();

	mline = curline;
	mchar = curchar;

	ToMark(m);
	if (MarkHighlighting)
		makedirty(m->m_line);
	MarkSet(m, mline, mchar);
}

/* Fix marks after a deletion. */

void
DFixMarks(line1, char1, line2, char2)
register LinePtr	line1,
		line2;
int	char1,
	char2;
{
	register Mark	*m;
	LinePtr	lp;

	if (curbuf->b_marks == NULL)
		return;

	for (lp = line1; lp != line2->l_next; lp = lp->l_next) {
		for (m = curbuf->b_marks; m != NULL; m = m->m_next) {
			if (m->m_line == lp
			&& (lp != line1 || m->m_char > char1))
			{
				if (lp == line2 && m->m_char > char2) {
					m->m_char -= char2-char1;
				} else {
					m->m_char = char1;
					if (line1 != line2)
						m->m_big_delete = YES;
				}
				m->m_line = line1;
			}
		}
	}
}

/* Fix marks after an insertion. */

void
IFixMarks(line1, char1, line2, char2)
register LinePtr	line1,
		line2;
int	char1,
	char2;
{
	register Mark	*m;

	for (m = curbuf->b_marks; m != NULL; m = m->m_next) {
		if (m->m_line == line1 && m->m_char > char1) {
			m->m_line = line2;
			m->m_char += char2 - char1;
		}
	}
}