From 83cebf33749d940b2919af98816fd7deeb5b981f Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Marco=20Diego=20Aur=C3=A9lio=20Mesquita?=
 <address@hidden>
Date: Sun, 26 Apr 2020 15:25:15 -0300
Subject: [PATCH 2/2] Initial softwrap support for scrollbar

---
 src/cut.c   |  3 +++
 src/nano.c  | 23 ++++++++++++++++-------
 src/nano.h  |  2 ++
 src/winio.c | 29 +++++++++++++++++++++++------
 4 files changed, 44 insertions(+), 13 deletions(-)

diff --git a/src/cut.c b/src/cut.c
index fbc145c3..cc42dd3e 100644
--- a/src/cut.c
+++ b/src/cut.c
@@ -112,6 +112,9 @@ void do_deletion(undo_type action)
 #endif
 
 	set_modified();
+
+	if (old_amount != number_of_chunks_in(openfile->current))
+		renumber_from(openfile->current);
 }
 
 /* Delete the character under the cursor. */
diff --git a/src/nano.c b/src/nano.c
index 5ede45bb..fbc06986 100644
--- a/src/nano.c
+++ b/src/nano.c
@@ -75,6 +75,9 @@ linestruct *make_new_node(linestruct *prevnode)
 	newnode->multidata = NULL;
 #endif
 	newnode->lineno = (prevnode) ? prevnode->lineno + 1 : 1;
+	newnode->chunk_nr = (prevnode) ?
+		number_of_chunks_in(prevnode) + prevnode->chunk_nr + 1
+		: 1;
 #ifndef NANO_TINY
 	newnode->has_anchor = FALSE;
 #endif
@@ -150,6 +153,7 @@ linestruct *copy_node(const linestruct *src)
 	dst->multidata = NULL;
 #endif
 	dst->lineno = src->lineno;
+	dst->chunk_nr = src->chunk_nr;
 #ifndef NANO_TINY
 	dst->has_anchor = FALSE;
 #endif
@@ -188,6 +192,9 @@ void renumber_from(linestruct *line)
 
 	while (line != NULL) {
 		line->lineno = ++number;
+		line->chunk_nr = (line->prev) ?
+			number_of_chunks_in(line->prev) + line->prev->chunk_nr + 1
+			: 1;
 		line = line->next;
 	}
 }
@@ -1042,7 +1049,7 @@ void regenerate_screen(void)
 	LINES = win.ws_row;
 #endif
 #ifndef NANO_TINY
-	thebar = (LINES > 5 && COLS > 9 && !ISSET(SOFTWRAP)) ? 1 : 0;
+	thebar = (LINES > 5 && COLS > 9) ? 1 : 0;
 	bardata = nrealloc(bardata, LINES * sizeof(int));
 #endif
 	editwincols = COLS - margin - thebar;
@@ -1086,12 +1093,11 @@ void do_toggle(int flag)
 			signal_init();
 			break;
 		case SOFTWRAP:
-			if (!ISSET(SOFTWRAP)) {
-				thebar = (LINES > 5 && COLS > 9) ? 1 : 0;
-				bardata = nrealloc(bardata, LINES * sizeof(int));
+			if (!ISSET(SOFTWRAP))
 				openfile->firstcolumn = 0;
-			} else
-				thebar  = 0;
+
+			thebar = (LINES > 5 && COLS > 9) ? 1 : 0;
+			bardata = nrealloc(bardata, LINES * sizeof(int));
 			editwincols = COLS - margin - thebar;
 			refresh_needed = TRUE;
 			break;
@@ -1502,6 +1508,9 @@ void inject(char *burst, size_t count)
 #endif
 	if (!refresh_needed)
 		update_line(openfile->current, openfile->current_x);
+
+	if (number_of_chunks_in(openfile->current) != old_amount)
+		renumber_from(openfile->current);
 }
 
 /* Read in a keystroke, and execute its command or insert it into the buffer. */
@@ -2289,7 +2298,7 @@ int main(int argc, char **argv)
 	curs_set(0);
 
 #ifndef NANO_TINY
-	thebar = (LINES > 5 && COLS > 9 && !ISSET(SOFTWRAP)) ? 1 : 0;
+	thebar = (LINES > 5 && COLS > 9) ? 1 : 0;
 	bardata = nrealloc(bardata, LINES * sizeof(int));
 #endif
 	editwincols = COLS - thebar;
diff --git a/src/nano.h b/src/nano.h
index dffabe70..88201da3 100644
--- a/src/nano.h
+++ b/src/nano.h
@@ -284,6 +284,8 @@ typedef struct linestruct {
 		/* The text of this line. */
 	ssize_t lineno;
 		/* The number of this line. */
+	ssize_t chunk_nr;
+		/* The number of this logical line. */
 	struct linestruct *next;
 		/* Next node. */
 	struct linestruct *prev;
diff --git a/src/winio.c b/src/winio.c
index aae1b8bd..8d1550f6 100644
--- a/src/winio.c
+++ b/src/winio.c
@@ -2412,7 +2412,7 @@ void draw_row(int row, const char *converted, linestruct *line, size_t from_col)
 	if (is_shorter || ISSET(SOFTWRAP))
 		wclrtoeol(edit);
 
-	if (is_shorter && thebar)
+	if (thebar)
 		mvwaddch(edit, row, COLS - 1, bardata[row]);
 
 #ifdef USING_OLD_NCURSES
@@ -2967,12 +2967,24 @@ bool less_than_a_screenful(size_t was_lineno, size_t was_leftedge)
 /* Draw a scroll bar on the righthand side of the screen. */
 void draw_scrollbar(void)
 {
-	int totalrows = openfile->filebot->lineno;
-	int lowest = ((openfile->edittop->lineno - 1) * editwinrows) / totalrows;
-	int highest = lowest + (editwinrows * editwinrows) / totalrows;
+	int rows_above = chunk_for(openfile->firstcolumn, openfile->edittop)
+				+ openfile->edittop->chunk_nr - 1;
+	int totalrows = openfile->filebot->chunk_nr;
+	int rows_below = totalrows - rows_above - editwinrows;
+	int top_row = openfile->edittop->chunk_nr
+			+ chunk_for(openfile->firstcolumn, openfile->edittop);
+
+	int lowest = rows_above;
+	int highest = editwinrows - rows_below - 1;
+
+	if (lowest > highest)
+		lowest = highest = top_row*(editwinrows - 1)/(totalrows - editwinrows);
 
-	if (editwinrows > totalrows)
-		highest = editwinrows;
+	if (lowest > editwinrows - 1)
+		lowest = editwinrows - 1;
+
+	if (totalrows < editwinrows)
+		lowest = highest = -1;
 
 	for (int row = 0; row < editwinrows; row++) {
 		bardata[row] = ' '|((row >= lowest && row <= highest) ? A_REVERSE : 0);
@@ -3034,6 +3046,11 @@ void edit_scroll(bool direction)
 										openfile->current_x : 0);
 		line = line->next;
 	}
+
+#ifndef NANO_TINY
+	if (thebar)
+		draw_scrollbar();
+#endif
 }
 
 #ifndef NANO_TINY
-- 
2.17.1