From 9b2eec24c2ba94886f1f196d99f2ffe9ac0b6d3b Mon Sep 17 00:00:00 2001
From: "Devin J. Pohly" <djpohly@gmail.com>
Date: Thu, 23 Apr 2020 00:27:53 -0500
Subject: [PATCH] add selclient() helper

This may get inlined later, but it's nice for now.  The focused client
if any should always be both at the top of fstack and visible on selmon.
---
 dwl.c | 24 ++++++++++++++++--------
 1 file changed, 16 insertions(+), 8 deletions(-)

diff --git a/dwl.c b/dwl.c
index 6a11390..737b71c 100644
--- a/dwl.c
+++ b/dwl.c
@@ -141,6 +141,7 @@ static void rendermon(struct wl_listener *listener, void *data);
 static void resize(Client *c, int x, int y, int w, int h);
 static void resizemouse(const Arg *arg);
 static void run(char *startup_cmd);
+static Client *selclient(void);
 static void setcursor(struct wl_listener *listener, void *data);
 static void setlayout(const Arg *arg);
 static void setup(void);
@@ -410,18 +411,16 @@ focus(Client *c, struct wlr_surface *surface)
 void
 focusnext(const Arg *arg)
 {
-	/* XXX will need more logic with clients on different monitors */
-	if (wl_list_length(&clients) < 2) {
+	Client *sel = selclient();
+	if (!sel)
 		return;
-	}
 	/* Find the selected client (top of fstack) and focus the client
 	 * following it in tiling order */
-	Client *c = wl_container_of(fstack.next, c, flink);
-	Client *n = wl_container_of(c->link.next, n, link);
+	Client *c = wl_container_of(sel->link.next, c, link);
 	/* Skip the sentinel node if we wrap around the end of the list */
-	if (&n->link == &clients)
-		n = wl_container_of(n->link.next, n, link);
-	focus(n, n->xdg_surface->surface);
+	if (&c->link == &clients)
+		c = wl_container_of(c->link.next, c, link);
+	focus(c, c->xdg_surface->surface);
 }
 
 void
@@ -849,6 +848,15 @@ run(char *startup_cmd)
 	}
 }
 
+Client *
+selclient(void)
+{
+	Client *c = wl_container_of(fstack.next, c, flink);
+	if (wl_list_empty(&fstack) || !VISIBLEON(c, selmon))
+		return NULL;
+	return c;
+}
+
 void
 setcursor(struct wl_listener *listener, void *data)
 {