/**************************************************************************
 *   folding.c  --  This file is part of GNU nano.                        *
 *                                                                        *
 *   Copyright (C) 2022 rexy712                                           *
 *                                                                        *
 *   GNU nano is free software: you can redistribute it and/or modify     *
 *   it under the terms of the GNU General Public License as published    *
 *   by the Free Software Foundation, either version 3 of the License,    *
 *   or (at your option) any later version.                               *
 *                                                                        *
 *   GNU nano is distributed in the hope that it will be useful,          *
 *   but WITHOUT ANY WARRANTY; without even the implied warranty          *
 *   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.              *
 *   See the GNU General Public License for more details.                 *
 *                                                                        *
 *   You should have received a copy of the GNU General Public License    *
 *   along with this program.  If not, see http://www.gnu.org/licenses/.  *
 *                                                                        *
 **************************************************************************/

#include "prototypes.h"

#include <ctype.h>
	/* isspace */

#ifdef ENABLE_FOLDING

/* Remove a folded segment from the given line until end of segment */
void unfold_folded_segment_from(linestruct *line)
{
	if (line != NULL)
		refresh_needed = TRUE;
	for(;line != NULL && line->folded;line = line->next)
		line->folded = FALSE;
}

/* Remove a folded segment containing the given line */
void unfold_folded_segment(linestruct *line)
{
	unfold_folded_segment_from(get_start_of_folded_segment(line));
}

/* Get the first member of the folded segment */
linestruct *get_start_of_folded_segment(linestruct *line)
{
	if (!line->folded)
		return line;

	while (line->prev != NULL && line->prev->folded)
		line = line->prev;

	return line;
}
/* Get the last member of the folded segment */
linestruct *get_end_of_folded_segment(linestruct *line)
{
	if (!line->folded)
		return line;

	while (line->next != NULL && line->next->folded)
		line = line->next;

	return line;
}

/* Get the span length of a folded_segment */
int get_folded_segment_length(linestruct *line)
{
	int i = 1;

	if (!line->folded)
		return 0;

	line = get_start_of_folded_segment(line);
	for (;line->next != NULL && line->next->folded;line = line->next)
		++i;
	return i;
}


/* Remove any folded_segments within the range [top, bottom].
 * Returns true if any segments are removed. */
bool do_unfold_segment(linestruct *line)
{
	/* Attempt to find a bracketed region first.
	 * If not, top is unmodified. */
	if (!line->folded) {
		linestruct *bot;
		find_bracketed_region(openfile->current, &line, &bot);
	}

	if (line->folded) {
		unfold_folded_segment(line);
		move_cursor_to_proper_column();
		return TRUE;
	}

	return FALSE;
}

/* Fold the currently selected lines unless the current selection
 * already contains a folded_segment. In that case, remove any
 * segments that are selected. */
void do_fold_segment(void)
{
	linestruct *top, *bot;
	get_range(&top, &bot);

	if (top == bot) {
		/* First try to unfold if this line/bracketed region is folded */
		if (do_unfold_segment(top))
			return;

		/* When not selecting multiple lines, try to find bounding
		 * brackets to act as top and bot. */
		if (!find_bracketed_region(openfile->current, &top, &bot)) {
			statusline(AHEM, _("No valid region found for automatic fold"));
			return;
		}
	}

	for (linestruct* line = top;line != bot->next;line = line->next)
		line->folded = TRUE;

	if (top->lineno < openfile->edittop->lineno &&
	    bot->lineno > openfile->edittop->lineno)
		openfile->edittop = top;

	/* Place the cursor at the start of the fold segment.
	 * Anywhere else within the segment is invalid. */
	if (openfile->current->folded)
		openfile->current = get_start_of_folded_segment(top);
	openfile->mark = NULL;

	refresh_needed = TRUE;
}

#endif /* ENABLE_FOLDING */