From bfcd3527dd7f14ce335ca8da7cf5f641254bd1f3 Mon Sep 17 00:00:00 2001
From: Maarten van Gompel <proycon@anaproy.nl>
Date: Tue, 29 Aug 2023 14:23:19 +0200
Subject: [PATCH] scroll wheel switches layers (as opposed to crashing as it
 did before)

---
 keyboard.c |  2 +-
 main.c     | 11 +++++++++++
 2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/keyboard.c b/keyboard.c
index b3d8819..a1b478e 100644
--- a/keyboard.c
+++ b/keyboard.c
@@ -62,7 +62,7 @@ kbd_next_layer(struct kbd *kb, struct key *k, bool invert) {
 			}
 			layer_index = layercount - 1;
 		}
-		kb->mods ^= Shift;
+		if (!invert) kb->mods ^= Shift;
 	} else {
 		// normal behaviour: switch to the next layout in the layer sequence
 		layer_index++;
diff --git a/main.c b/main.c
index 04a62f5..7921541 100644
--- a/main.c
+++ b/main.c
@@ -8,6 +8,7 @@
 #include <sys/signalfd.h>
 #include <poll.h>
 #include <unistd.h>
+#include <wayland-client-protocol.h>
 #include <wayland-client.h>
 #include <wchar.h>
 
@@ -70,6 +71,8 @@ static void wl_pointer_motion(void *data, struct wl_pointer *wl_pointer,
 static void wl_pointer_button(void *data, struct wl_pointer *wl_pointer,
                               uint32_t serial, uint32_t time, uint32_t button,
                               uint32_t state);
+static void wl_pointer_axis(void *data, struct wl_pointer *wl_pointer,
+                  uint32_t time, uint32_t axis, wl_fixed_t value);
 
 static void wl_touch_down(void *data, struct wl_touch *wl_touch,
                           uint32_t serial, uint32_t time,
@@ -113,6 +116,7 @@ static const struct wl_pointer_listener pointer_listener = {
   .leave = wl_pointer_leave,
   .motion = wl_pointer_motion,
   .button = wl_pointer_button,
+  .axis = wl_pointer_axis,
 };
 
 static const struct wl_touch_listener touch_listener = {
@@ -255,6 +259,13 @@ wl_pointer_button(void *data, struct wl_pointer *wl_pointer, uint32_t serial,
 	}
 }
 
+void
+wl_pointer_axis(void *data, struct wl_pointer *wl_pointer,
+                  uint32_t time, uint32_t axis, wl_fixed_t value) {
+	kbd_next_layer(&keyboard, NULL, (value >= 0));
+	drwsurf_flip(keyboard.surf);
+}
+
 void
 seat_handle_capabilities(void *data, struct wl_seat *wl_seat,
                          enum wl_seat_capability caps) {