add click on title_bar to focus a container

include/sway/container.h

@@ -243,6 +243,10 @@ swayc_t *swayc_active_workspace_for(swayc_t *view);
  * Finds the container currently underneath the pointer.
  */
 swayc_t *container_under_pointer(void);
+/**
+ * Finds the first container following a callback.
+ */
+swayc_t *container_find(swayc_t *container, bool (*f)(swayc_t *, const void *), const void *data);
 
 /**
  * Returns true if a container is fullscreen.

sway/container.c

@@ -722,6 +722,25 @@ swayc_t *container_under_pointer(void) {
 	return lookup;
 }
 
+swayc_t *container_find(swayc_t *container, bool (*f)(swayc_t *, const void *), const void *data) {
+	if (container->children == NULL || container->children->length == 0) {
+		return NULL;
+	}
+
+	for (int i = 0; i < container->children->length; ++i) {
+		if (f(container->children->items[i], data)) {
+			return container->children->items[i];
+		}
+
+		swayc_t *find = container_find(container->children->items[i], f, data);
+		if (find != NULL) {
+			return find;
+		}
+	}
+
+	return NULL;
+}
+
 // Container information
 
 bool swayc_is_fullscreen(swayc_t *view) {

sway/handlers.c

@@ -776,6 +776,14 @@ static bool handle_pointer_motion(wlc_handle handle, uint32_t time, const struct
 	return EVENT_PASSTHROUGH;
 }
 
+bool swayc_border_check(swayc_t *c, const void *_origin) {
+	const struct wlc_point *origin = _origin;
+	if (origin->x >= c->title_bar_geometry.origin.x && origin->y >= c->title_bar_geometry.origin.y
+		&& origin->x < (c->title_bar_geometry.origin.x + (int)c->title_bar_geometry.size.w) && origin->y < (c->title_bar_geometry.origin.y + (int)c->title_bar_geometry.size.h)) {
+		return true;
+	}
+	return false;
+}
 
 static bool handle_pointer_button(wlc_handle view, uint32_t time, const struct wlc_modifiers *modifiers,
 		uint32_t button, enum wlc_button_state state, const struct wlc_point *origin) {
@@ -840,6 +848,13 @@ static bool handle_pointer_button(wlc_handle view, uint32_t time, const struct w
 	// Check whether to change focus
 	swayc_t *pointer = pointer_state.view;
 	if (pointer) {
+		swayc_t *ws = swayc_parent_by_type(focused, C_WORKSPACE);
+		swayc_t *find = container_find(ws, &swayc_border_check, origin);
+		if (find != NULL) {
+			set_focused_container(find);
+			return EVENT_HANDLED;
+		}
+
 		if (focused != pointer) {
 			set_focused_container(pointer_state.view);
 		}