Add support for wlr-layer-shell ON_DEMAND keyboard interactivity

This allows for layer shell surfaces to receive focus while the surface is explicitly focused, i.e allowing
text fields to receive keyboard input just like a regular surface.

6 files changed, 80 insertions, 13 deletions

diff --git a/include/sway/input/seat.h b/include/sway/input/seat.h
index 5ef8e2f3..35a96ace 100644
--- a/include/sway/input/seat.h
+++ b/include/sway/input/seat.h
@@ -104,8 +104,9 @@ struct sway_seat {
         struct sway_workspace *workspace;
         char *prev_workspace_name; // for workspace back_and_forth
 
-        // If the focused layer is set, views cannot receive keyboard focus
         struct wlr_layer_surface_v1 *focused_layer;
+        // If the exclusive layer is set, views cannot receive keyboard focus
+        bool has_exclusive_layer;
 
         // If exclusive_client is set, no other clients will receive input events
         struct wl_client *exclusive_client;
diff --git a/include/sway/layers.h b/include/sway/layers.h
index f8508493..9220bdb5 100644
--- a/include/sway/layers.h
+++ b/include/sway/layers.h
@@ -55,6 +55,10 @@ struct sway_layer_subsurface {
 };
 
 struct sway_output;
+
+struct wlr_layer_surface_v1 *toplevel_layer_surface_from_surface(
+                struct wlr_surface *surface);
+
 void arrange_layers(struct sway_output *output);
 
 struct sway_layer_surface *layer_from_wlr_layer_surface_v1(
diff --git a/sway/desktop/layer_shell.c b/sway/desktop/layer_shell.c
index 50aa6938..d990d92a 100644
--- a/sway/desktop/layer_shell.c
+++ b/sway/desktop/layer_shell.c
@@ -17,6 +17,39 @@
 #include "sway/tree/arrange.h"
 #include "sway/tree/workspace.h"
 
+struct wlr_layer_surface_v1 *toplevel_layer_surface_from_surface(
+                struct wlr_surface *surface) {
+        struct wlr_layer_surface_v1 *layer;
+        do {
+                if (!surface) {
+                        return NULL;
+                }
+                // Topmost layer surface
+                if ((layer = wlr_layer_surface_v1_try_from_wlr_surface(surface))) {
+                        return layer;
+                }
+                // Layer subsurface
+                if (wlr_subsurface_try_from_wlr_surface(surface)) {
+                        surface = wlr_surface_get_root_surface(surface);
+                        continue;
+                }
+
+                // Layer surface popup
+                struct wlr_xdg_surface * xdg_popup = NULL;
+                if ((xdg_popup = wlr_xdg_surface_try_from_wlr_surface(surface)) &&
+                                xdg_popup->role == WLR_XDG_SURFACE_ROLE_POPUP) {
+                        if (!xdg_popup->popup->parent) {
+                                return NULL;
+                        }
+                        surface = wlr_surface_get_root_surface(xdg_popup->popup->parent);
+                        continue;
+                }
+
+                // Return early if the surface is not a layer/xdg_popup/sub surface
+                return NULL;
+        } while (true);
+}
+
 static void apply_exclusive(struct wlr_box *usable_area,
                 uint32_t anchor, int32_t exclusive,
                 int32_t margin_top, int32_t margin_right,
@@ -218,7 +251,8 @@ void arrange_layers(struct sway_output *output) {
         for (size_t i = 0; i < nlayers; ++i) {
                 wl_list_for_each_reverse(layer,
                                 &output->layers[layers_above_shell[i]], link) {
-                        if (layer->layer_surface->current.keyboard_interactive &&
+                        if (layer->layer_surface->current.keyboard_interactive
+                                        == ZWLR_LAYER_SURFACE_V1_KEYBOARD_INTERACTIVITY_EXCLUSIVE &&
                                         layer->layer_surface->surface->mapped) {
                                 topmost = layer;
                                 break;
@@ -231,10 +265,12 @@ void arrange_layers(struct sway_output *output) {
 
         struct sway_seat *seat;
         wl_list_for_each(seat, &server.input->seats, link) {
+                seat->has_exclusive_layer = false;
                 if (topmost != NULL) {
                         seat_set_focus_layer(seat, topmost->layer_surface);
                 } else if (seat->focused_layer &&
-                                !seat->focused_layer->current.keyboard_interactive) {
+                                seat->focused_layer->current.keyboard_interactive
+                                        != ZWLR_LAYER_SURFACE_V1_KEYBOARD_INTERACTIVITY_EXCLUSIVE) {
                         seat_set_focus_layer(seat, NULL);
                 }
         }
diff --git a/sway/input/seat.c b/sway/input/seat.c
index 5795f40f..fdd21057 100644
--- a/sway/input/seat.c
+++ b/sway/input/seat.c
@@ -1295,11 +1295,15 @@ static void seat_set_workspace_focus(struct sway_seat *seat, struct sway_node *n
 }
 
 void seat_set_focus(struct sway_seat *seat, struct sway_node *node) {
-        if (seat->focused_layer) {
+        // Prevents the layer from losing focus if it has keyboard exclusivity
+        if (seat->has_exclusive_layer) {
                 struct wlr_layer_surface_v1 *layer = seat->focused_layer;
                 seat_set_focus_layer(seat, NULL);
                 seat_set_workspace_focus(seat, node);
                 seat_set_focus_layer(seat, layer);
+        } else if (seat->focused_layer) {
+                seat_set_focus_layer(seat, NULL);
+                seat_set_workspace_focus(seat, node);
         } else {
                 seat_set_workspace_focus(seat, node);
         }
@@ -1347,14 +1351,20 @@ void seat_set_focus_layer(struct sway_seat *seat,
                         seat_set_focus(seat, previous);
                 }
                 return;
-        } else if (!layer || seat->focused_layer == layer) {
+        } else if (!layer) {
                 return;
         }
         assert(layer->surface->mapped);
-        seat_set_focus_surface(seat, layer->surface, true);
-        if (layer->current.layer >= ZWLR_LAYER_SHELL_V1_LAYER_TOP) {
-                seat->focused_layer = layer;
+        if (layer->current.layer >= ZWLR_LAYER_SHELL_V1_LAYER_TOP &&
+                        layer->current.keyboard_interactive
+                        == ZWLR_LAYER_SURFACE_V1_KEYBOARD_INTERACTIVITY_EXCLUSIVE) {
+                seat->has_exclusive_layer = true;
+        }
+        if (seat->focused_layer == layer) {
+                return;
         }
+        seat_set_focus_surface(seat, layer->surface, true);
+        seat->focused_layer = layer;
 }
 
 void seat_set_exclusive_client(struct sway_seat *seat,
diff --git a/sway/input/seatop_default.c b/sway/input/seatop_default.c
index 5a55c186..f4c63808 100644
--- a/sway/input/seatop_default.c
+++ b/sway/input/seatop_default.c
@@ -2,6 +2,7 @@
 #include <float.h>
 #include <libevdev/libevdev.h>
 #include <wlr/types/wlr_cursor.h>
+#include <wlr/types/wlr_subcompositor.h>
 #include <wlr/types/wlr_tablet_v2.h>
 #include <wlr/types/wlr_xcursor_manager.h>
 #include "gesture.h"
@@ -9,6 +10,7 @@
 #include "sway/input/cursor.h"
 #include "sway/input/seat.h"
 #include "sway/input/tablet.h"
+#include "sway/layers.h"
 #include "sway/output.h"
 #include "sway/tree/view.h"
 #include "sway/tree/workspace.h"
@@ -365,10 +367,9 @@ static void handle_button(struct sway_seat *seat, uint32_t time_msec,
                 return;
         }
 
-        // Handle clicking a layer surface
-        struct wlr_layer_surface_v1 *layer;
-        if (surface &&
-                        (layer = wlr_layer_surface_v1_try_from_wlr_surface(surface))) {
+        // Handle clicking a layer surface and its popups/subsurfaces
+        struct wlr_layer_surface_v1 *layer = NULL;
+        if ((layer = toplevel_layer_surface_from_surface(surface))) {
                 if (layer->current.keyboard_interactive) {
                         seat_set_focus_layer(seat, layer);
                         transaction_commit_dirty();
@@ -544,6 +545,21 @@ static void check_focus_follows_mouse(struct sway_seat *seat,
                 if (wlr_output == NULL) {
                         return;
                 }
+
+                struct wlr_surface *surface = NULL;
+                double sx, sy;
+                node_at_coords(seat, seat->cursor->cursor->x, seat->cursor->cursor->y,
+                                &surface, &sx, &sy);
+
+                // Focus topmost layer surface
+                struct wlr_layer_surface_v1 *layer = NULL;
+                if ((layer = toplevel_layer_surface_from_surface(surface)) &&
+                                layer->current.keyboard_interactive) {
+                        seat_set_focus_layer(seat, layer);
+                        transaction_commit_dirty();
+                        return;
+                }
+
                 struct sway_output *hovered_output = wlr_output->data;
                 if (focus && hovered_output != node_get_output(focus)) {
                         struct sway_workspace *ws = output_get_active_workspace(hovered_output);
diff --git a/sway/server.c b/sway/server.c
index 0cf767b7..c87e30fd 100644
--- a/sway/server.c
+++ b/sway/server.c
@@ -55,7 +55,7 @@
 #endif
 
 #define SWAY_XDG_SHELL_VERSION 2
-#define SWAY_LAYER_SHELL_VERSION 3
+#define SWAY_LAYER_SHELL_VERSION 4
 
 #if WLR_HAS_DRM_BACKEND
 static void handle_drm_lease_request(struct wl_listener *listener, void *data) {