Highlight matching cursor symbol

3 files changed, 41 insertions, 16 deletions

diff --git a/text-motions.c b/text-motions.c
index 00e3cc8..d2f272c 100644
--- a/text-motions.c
+++ b/text-motions.c
@@ -329,12 +329,17 @@ size_t text_paragraph_prev(Text *txt, size_t pos) {
 }
 
 size_t text_bracket_match(Text *txt, size_t pos) {
+	return text_bracket_match_except(txt, pos, NULL);
+}
+
+size_t text_bracket_match_except(Text *txt, size_t pos, const char *except) {
 	int direction, count = 1;
 	char search, current, c;
 	Iterator it = text_iterator_get(txt, pos);
 	if (!text_iterator_byte_get(&it, &current))
 		return pos;
-
+	if (except && memchr(except, current, strlen(except)))
+		return pos;
 	switch (current) {
 	case '(': search = ')'; direction =  1; break;
 	case ')': search = '('; direction = -1; break;
@@ -347,7 +352,7 @@ size_t text_bracket_match(Text *txt, size_t pos) {
 	case '"':
 	case '`':
 	case '\'': {
-		char special[] = " \n)}]>.,";
+		char special[] = " \n)}]>.,:;";
 		search = current;
 		direction = 1;
 		if (text_iterator_byte_next(&it, &c)) {
diff --git a/text-motions.h b/text-motions.h
index dca9fac..e2dc064 100644
--- a/text-motions.h
+++ b/text-motions.h
@@ -76,6 +76,8 @@ size_t text_section_prev(Text*, size_t pos);
 */
 /* search coresponding '(', ')', '{', '}', '[', ']', '>', '<', '"', ''' */
 size_t text_bracket_match(Text*, size_t pos);
+/* same as above but ignore symbols contained in last argument */
+size_t text_bracket_match_except(Text*, size_t pos, const char *except);
 
 /* search the given regex pattern in either forward or backward direction,
  * starting from pos. does wrap around if no match was found. */
diff --git a/window.c b/window.c
index fe5eac3..1f22988 100644
--- a/window.c
+++ b/window.c
@@ -30,6 +30,7 @@ typedef struct {            /* cursor position */
 	Filepos pos;        /* in bytes from the start of the file */
 	int row, col;       /* in terms of zero based screen coordinates */
 	Line *line;         /* screen line on which cursor currently resides */
+	bool highlighted;   /* true e.g. when cursor is on a bracket */
 } Cursor;
 
 struct Win {                /* window showing part of a file */
@@ -234,20 +235,6 @@ CursorPos window_cursor_getpos(Win *win) {
 	return pos;
 }
 
-/* place the cursor according to the screen coordinates in win->{row,col} and
- * fire user callback. if a selection is active, redraw the window to reflect
- * its changes. */
-static size_t window_cursor_update(Win *win) {
-	Cursor *cursor = &win->cursor;
-	if (win->sel.start != EPOS) {
-		win->sel.end = cursor->pos;
-		window_draw(win);
-	}
-	if (win->ui)
-		win->ui->cursor_to(win->ui, cursor->col, cursor->row);
-	return cursor->pos;
-}
-
 /* snyc current cursor position with internal Line/Cell structures */
 static void window_cursor_sync(Win *win) {
 	int row = 0, col = 0;
@@ -279,6 +266,37 @@ static void window_cursor_sync(Win *win) {
 	win->cursor.col = col;
 }
 
+/* place the cursor according to the screen coordinates in win->{row,col} and
+ * fire user callback. if a selection is active, redraw the window to reflect
+ * its changes. */
+static size_t window_cursor_update(Win *win) {
+	Cursor *cursor = &win->cursor;
+	if (win->sel.start != EPOS) {
+		win->sel.end = cursor->pos;
+		window_draw(win);
+	} else if (win->ui && win->syntax) {
+		size_t pos = cursor->pos;
+		size_t pos_match = text_bracket_match_except(win->text, pos, "<>");
+		if (pos != pos_match && win->start <= pos_match && pos_match < win->end) {
+			if (cursor->highlighted)
+				window_draw(win); /* clear active highlighting */
+			cursor->pos = pos_match;
+			window_cursor_sync(win);
+			cursor->line->cells[cursor->col].attr |= A_REVERSE;
+			cursor->pos = pos;
+			window_cursor_sync(win);
+			win->ui->draw_text(win->ui, win->topline);
+			cursor->highlighted = true;
+		} else if (cursor->highlighted) {
+			cursor->highlighted = false;
+			window_draw(win);
+		}
+	}
+	if (win->ui)
+		win->ui->cursor_to(win->ui, cursor->col, cursor->row);
+	return cursor->pos;
+}
+
 /* move the cursor to the character at pos bytes from the begining of the file.
  * if pos is not in the current viewport, redraw the window to make it visible */
 void window_cursor_to(Win *win, size_t pos) {