From 90d80c0de900b03d36c081423855b18c5fa02f56 Mon Sep 17 00:00:00 2001
From: "Devin J. Pohly" <djpohly@gmail.com>
Date: Fri, 31 Jul 2020 13:53:33 -0500
Subject: [PATCH] simplify focusclient

This arranges the function into some logical tasks: deactivate the old
client, update wlroots' keyboard focus, update our data structures, and
activate the new client.  The last two only need to be done when
focusing something new, so an early return saves some horizontal space.
---
 dwl.c | 79 ++++++++++++++++++++++++-----------------------------------
 1 file changed, 32 insertions(+), 47 deletions(-)

diff --git a/dwl.c b/dwl.c
index 7cc022d..a8ce00c 100644
--- a/dwl.c
+++ b/dwl.c
@@ -681,62 +681,47 @@ dirtomon(int dir)
 void
 focusclient(Client *c, struct wlr_surface *surface, int lift)
 {
-	Client *sel = selclient();
-	struct wlr_keyboard *kb;
-	/* Previously focused surface */
-	struct wlr_surface *psurface = seat->keyboard_state.focused_surface;
+	Client *old = selclient();
+	struct wlr_keyboard *kb = wlr_seat_get_keyboard(seat);
 
-	if (c) {
-		/* assert(VISIBLEON(c, c->mon)); ? */
-		/* Use top-level wlr_surface if nothing more specific given */
-		if (!surface)
-			surface = WLR_SURFACE(c);
+	/* Use top-level wlr_surface if nothing more specific is given */
+	if (c && !surface)
+		surface = WLR_SURFACE(c);
 
-		/* Focus the correct monitor (must come after selclient!) */
-		selmon = c->mon;
-
-		/* Move the client to the front of the focus stack */
-		wl_list_remove(&c->flink);
-		wl_list_insert(&fstack, &c->flink);
-
-		/* Also raise client in stacking order if requested */
-		if (lift) {
-			wl_list_remove(&c->slink);
-			wl_list_insert(&stack, &c->slink);
-		}
+	/* Deactivate old client if focus is changing */
+	if (c != old && old) {
+		if (old->type != XDGShell)
+			wlr_xwayland_surface_activate(old->xwayland_surface, 0);
+		else
+			wlr_xdg_toplevel_set_activated(old->xdg_surface, 0);
 	}
 
-	/*
-	 * If the focused surface has changed, tell the seat to have the
-	 * keyboard enter the new surface.  wlroots will keep track of this and
-	 * automatically send key events to the appropriate clients.  If surface
-	 * is NULL, we clear the focus instead.
-	 */
-	if (!surface) {
+	/* Update wlroots' keyboard focus */
+	if (!c) {
+		/* With no client, all we have left is to clear focus */
 		wlr_seat_keyboard_notify_clear_focus(seat);
-	} else if (surface != psurface) {
-		kb = wlr_seat_get_keyboard(seat);
+		return;
+	}
+	/* Otherwise, update the focus if it has changed */
+	if (surface != seat->keyboard_state.focused_surface)
 		wlr_seat_keyboard_notify_enter(seat, surface,
 				kb->keycodes, kb->num_keycodes, &kb->modifiers);
+
+	/* Select client's monitor, move it to the top of the focus stack, and
+	 * raise it in the stacking order if requested. */
+	selmon = c->mon;
+	wl_list_remove(&c->flink);
+	wl_list_insert(&fstack, &c->flink);
+	if (lift) {
+		wl_list_remove(&c->slink);
+		wl_list_insert(&stack, &c->slink);
 	}
 
-	/*
-	 * If the focused toplevel has changed, deactivate the old one. Always
-	 * activate the current one.  This lets the clients know to repaint
-	 * accordingly, e.g. show/hide a caret.
-	 */
-	if (c != sel && sel) {
-		if (sel->type != XDGShell)
-			wlr_xwayland_surface_activate(sel->xwayland_surface, 0);
-		else
-			wlr_xdg_toplevel_set_activated(sel->xdg_surface, 0);
-	}
-	if (c) {
-		if (c->type != XDGShell)
-			wlr_xwayland_surface_activate(c->xwayland_surface, 1);
-		else
-			wlr_xdg_toplevel_set_activated(c->xdg_surface, 1);
-	}
+	/* Activate the new client */
+	if (c->type != XDGShell)
+		wlr_xwayland_surface_activate(c->xwayland_surface, 1);
+	else
+		wlr_xdg_toplevel_set_activated(c->xdg_surface, 1);
 }
 
 void