commit 4dd664cea4f1c5745dac573900e48c1fee5ab151
from: Omar Polo <op@omarpolo.com>
date: Sat Mar 06 18:56:53 2021 UTC

update cmd_{previous,next}_line

cmd_{previous,next}_line used COLS and LINES, this adapts them to
body_{cols,lines}.

While there, also add the ability to scroll when trying to go past the
beginning/end of the screen.

commit - bef915e1bacbb9d875ac9f5019838eb51be56d5f
commit + 4dd664cea4f1c5745dac573900e48c1fee5ab151
blob - 5e63c85183b2ce46f30bc05c4ef898a8477dd153
blob + 9624f972f1373e83d8466b059f74691d240a326c
--- ui.c
+++ ui.c
@@ -190,7 +190,12 @@ cmd_previous_line(int k)
 	struct tab	*tab;
 
 	tab = current_tab();
-	tab->s->curs_y = MAX(0, tab->s->curs_y-1);
+
+	if (--tab->s->curs_y < 0) {
+		tab->s->curs_y = 0;
+		cmd_scroll_up(k);
+	}
+
 	restore_cursor(tab);
 }
 
@@ -200,7 +205,12 @@ cmd_next_line(int k)
 	struct tab	*tab;
 
 	tab = current_tab();
-	tab->s->curs_y = MIN(LINES-1, tab->s->curs_y+1);
+
+	if (++tab->s->curs_y > body_lines-1) {
+		tab->s->curs_y = body_lines-1;
+		cmd_scroll_down(k);
+	}
+
 	restore_cursor(tab);
 }
 
@@ -210,7 +220,7 @@ cmd_forward_char(int k)
 	struct tab	*tab;
 
 	tab = current_tab();
-	tab->s->curs_x = MIN(COLS-1, tab->s->curs_x+1);
+	tab->s->curs_x = MIN(body_cols-1, tab->s->curs_x+1);
 	restore_cursor(tab);
 }