Fix decoration drift during animated transitions; checkpoint IPC/global-menu/output-management work

Border/titlebar decoration was built from Window.geometry (the animation's
final target) in both wayland backends' render loops, while sync_geometry
already draws a window's actual content at window_anims' interpolated rect
during any maximize/fullscreen/open-slide tween. Border and content read two
different rectangles for the whole transition, so the border visibly
detached from the window it was outlining - reported as "borders aren't
flush." Both udev.rs and winit.rs now read the same animated rect for
titlebar placement, border-strip placement, and the occlusion test against
later windows in stacking order. Verified: cargo build --workspace, cargo
clippy (0 new warnings), cargo test -p srdwm-core (111/111).

Also checkpoints substantial protocol/IPC work from prior sessions that had
accumulated uncommitted: gtk-shell1 support (gtk_shell.rs, the vendored
gtk-shell.xml, xwayland.rs's X11-side mirror) backing the global app menu;
zwlr_foreign_toplevel_manager_v1 (foreign_toplevel.rs) broadcasting distinct
maximized/minimized/fullscreen/activated state per window; output_management
(ext-output-management + layer-shell exclusive-zone reservation tracking);
workspace.rs and context_menu.rs; a Unix-socket IPC crate (platform/src/
ipc.rs) and a `srd` control-CLI crate (crates/ctl); xkb_config.rs; and a
theme module (core/src/theme.rs). A peer session working the AGS shell
concurrently verified several of these live against a running srdwm: the
global menu rendering a real app's File/Edit menu over gtk-shell1, and
foreign-toplevel correctly reporting maximized and fullscreen as independent,
non-simultaneous states with the geometry each implies (maximize stops at a
reserved top bar and past a dock; fullscreen reaches the true monitor edge).

1 files changed, 518 insertions, 14 deletions

diff --git a/crates/wayland/src/protocols.rs b/crates/wayland/src/protocols.rs
index f51b35d..a0aed3f 100644
--- a/crates/wayland/src/protocols.rs
+++ b/crates/wayland/src/protocols.rs
@@ -7,34 +7,44 @@
 //! session-lock handler is the one exception, living in [`crate::lock`]
 //! alongside the rest of that feature.
 
-use smithay::desktop::{layer_map_for_output, LayerSurface as DesktopLayerSurface};
-use smithay::input::pointer::CursorImageStatus;
+use smithay::desktop::{find_popup_root_surface, layer_map_for_output, LayerSurface as DesktopLayerSurface, PopupKeyboardGrab, PopupKind, PopupPointerGrab};
+use smithay::input::pointer::{CursorImageStatus, Focus};
 use smithay::input::{Seat, SeatHandler, SeatState};
 use smithay::reexports::wayland_protocols::xdg::decoration::zv1::server::zxdg_toplevel_decoration_v1::Mode as DecorationMode;
+use smithay::reexports::wayland_protocols::xdg::shell::server::xdg_toplevel;
 use smithay::reexports::wayland_server::protocol::wl_buffer::WlBuffer;
 use smithay::reexports::wayland_server::protocol::wl_output::WlOutput;
 use smithay::reexports::wayland_server::protocol::wl_seat;
 use smithay::reexports::wayland_server::protocol::wl_surface::WlSurface;
 use smithay::reexports::wayland_server::Client;
+use smithay::reexports::wayland_server::Resource;
+use smithay::backend::allocator::dmabuf::Dmabuf;
+use smithay::backend::renderer::ImportDma;
 use smithay::utils::Serial;
 use smithay::wayland::buffer::BufferHandler;
 use smithay::wayland::compositor::{CompositorClientState, CompositorHandler, CompositorState};
+use smithay::wayland::dmabuf::{DmabufGlobal, DmabufHandler, DmabufState, ImportNotifier};
+use smithay::wayland::xdg_activation::{XdgActivationHandler, XdgActivationState, XdgActivationToken, XdgActivationTokenData};
+use smithay::wayland::input_method::PopupSurface as ImePopupSurface;
 use smithay::wayland::selection::data_device::{
     ClientDndGrabHandler, DataDeviceHandler, DataDeviceState, ServerDndGrabHandler,
 };
 use smithay::wayland::selection::primary_selection::{PrimarySelectionHandler, PrimarySelectionState};
 use smithay::wayland::selection::wlr_data_control::{DataControlHandler, DataControlState};
+use smithay::wayland::compositor::{add_pre_commit_hook, with_states};
 use smithay::wayland::selection::SelectionHandler;
 use smithay::wayland::shell::wlr_layer::{
-    Layer, LayerSurface as WlrLayerSurface, WlrLayerShellHandler, WlrLayerShellState,
+    Layer, LayerSurface as WlrLayerSurface, LayerSurfaceCachedState, WlrLayerShellHandler, WlrLayerShellState,
 };
 use smithay::wayland::shell::xdg::decoration::XdgDecorationHandler;
 use smithay::wayland::shell::xdg::{PopupSurface, PositionerState, ToplevelSurface, XdgShellHandler, XdgShellState};
 use smithay::wayland::shm::{ShmHandler, ShmState};
+use smithay::wayland::tablet_manager::TabletSeatHandler;
 use smithay::{
-    delegate_compositor, delegate_data_control, delegate_data_device, delegate_layer_shell, delegate_output,
-    delegate_primary_selection, delegate_seat, delegate_session_lock, delegate_shm, delegate_xdg_decoration,
-    delegate_xdg_shell,
+    delegate_compositor, delegate_cursor_shape, delegate_data_control, delegate_data_device, delegate_dmabuf,
+    delegate_layer_shell, delegate_output, delegate_primary_selection, delegate_seat, delegate_session_lock,
+    delegate_shm, delegate_xdg_activation, delegate_xdg_decoration, delegate_xdg_shell,
+    delegate_input_method_manager, delegate_text_input_manager,
 };
 
 use crate::state::{ClientState, CompState};
@@ -55,6 +65,52 @@ impl CompositorHandler for CompState {
         &client.get_data::<smithay::xwayland::XWaylandClientData>().expect("client is neither ours nor XWayland's").compositor_state
     }
 
+    /// Workaround for a real smithay bug (see docs/PANEL_SUPPORT_TODO.md and
+    /// `layer_destroyed` below): destroying a `zwlr_layer_surface_v1` role
+    /// resets the surface's `LayerSurfaceCachedState` to
+    /// `Default::default()` (size 0x0, no anchor) rather than removing it,
+    /// but the pre-commit hook smithay itself registers at
+    /// `get_layer_surface` time keeps validating that state against every
+    /// future commit regardless of whether the role still exists --
+    /// tripping its own `width/height 0 requested without ... anchors`
+    /// check and posting `invalid_size`, which kills the client's whole
+    /// connection over what is protocol-legal (committing a now-roleless
+    /// surface).
+    ///
+    /// Fixed by registering our own pre-commit hook here, in `new_surface`
+    /// - called at `wl_compositor.create_surface`, strictly before any
+    /// later `get_layer_surface` on the same surface could register
+    /// smithay's own hook. Hooks run in registration order (`tree.rs`:
+    /// `pre_commit_hooks` is a plain `Vec`, pushed and iterated in order),
+    /// so ours always runs first and can neutralize the stale reset state
+    /// before smithay's hook ever inspects it. This depends on that
+    /// ordering guarantee holding in future smithay versions - it isn't
+    /// documented as an API contract, just an implementation detail
+    /// confirmed against 0.7.0's source - so re-check this file against
+    /// whatever smithay version replaces it.
+    ///
+    /// Cost: one closure registered per `wl_surface` (not just layer
+    /// surfaces, since we don't know in advance which ones will become
+    /// one), each a no-op unless that exact surface is in
+    /// `dead_layer_surfaces`.
+    fn new_surface(&mut self, surface: &WlSurface) {
+        add_pre_commit_hook::<CompState, _>(surface, |state, _dh, surface| {
+            if !state.dead_layer_surfaces.contains(surface) {
+                return;
+            }
+            with_states(surface, |states| {
+                let mut cached = states.cached_state.get::<LayerSurfaceCachedState>();
+                let pending = cached.pending();
+                if pending.size.w == 0 && !pending.anchor.anchored_horizontally() {
+                    pending.size.w = 1;
+                }
+                if pending.size.h == 0 && !pending.anchor.anchored_vertically() {
+                    pending.size.h = 1;
+                }
+            });
+        });
+    }
+
     fn commit(&mut self, surface: &WlSurface) {
         smithay::backend::renderer::utils::on_commit_buffer_handler::<CompState>(surface);
         // XWayland's association of an X11 window with this wl_surface can
@@ -67,8 +123,16 @@ impl CompositorHandler for CompState {
             if let Some(w) = self.id_to_window.get(&id) {
                 w.on_commit();
             }
+            crate::state::sync_toplevel_metadata(self, id, surface);
         }
         self.ensure_layer_initial_configure(surface);
+        // Advances a just-created popup from unmapped to mapped (needed for
+        // `PopupManager::popups_for_surface`, which `popup_render_elements`
+        // reads at render time) and prunes dead ones. Cheap and only does
+        // real work on a popup-role surface, so doing it on every commit
+        // rather than throttling is not worth the extra bookkeeping.
+        self.popups.commit(surface);
+        self.popups.cleanup();
     }
 }
 
@@ -81,11 +145,204 @@ impl XdgShellHandler for CompState {
         self.new_managed_window(surface);
     }
 
-    fn new_popup(&mut self, _surface: PopupSurface, _positioner: PositionerState) {}
+    /// `move_request`/`resize_request` were also still smithay's default
+    /// no-op implementations - a much larger gap than the five below:
+    /// this is *how a client-side-decorated window gets dragged or resized
+    /// by its own titlebar/edges at all*. A window we draw our own
+    /// decoration for never needed this (`TitlebarHit::Drag`/`Resize` in
+    /// `input.rs` detect the click directly, since we own those pixels),
+    /// but a window that negotiated client-side decoration and draws its
+    /// own titlebar - Firefox, and most GTK4 apps by default - handles
+    /// the click itself and then asks the compositor to actually perform
+    /// the move/resize via exactly these two requests. Left unimplemented,
+    /// dragging or resizing any such window by its own chrome did
+    /// nothing at all - the only way to reposition it was the
+    /// modifier+drag-anywhere gesture (`bindm`), which most users have no
+    /// reason to know exists and doesn't work for resize-from-a-specific-
+    /// edge at all. Reuses the exact same `WindowManager::start_drag`/
+    /// `start_resize` the pointer-driven titlebar handlers call --
+    /// `handle_pointer_position`/`handle_pointer_button` already drive any
+    /// in-progress drag/resize to completion on subsequent motion/release
+    /// regardless of what started it, so no smithay pointer grab is
+    /// needed here at all, just the same start call from a different
+    /// trigger.
+    fn move_request(&mut self, surface: ToplevelSurface, _seat: wl_seat::WlSeat, _serial: Serial) {
+        if let Some(&id) = self.surface_to_id.get(surface.wl_surface()) {
+            let pos = crate::input::last_pointer_pos(self);
+            self.wm.borrow_mut().start_drag(id, pos.x as i32, pos.y as i32);
+        }
+    }
+
+    fn resize_request(&mut self, surface: ToplevelSurface, _seat: wl_seat::WlSeat, _serial: Serial, edges: xdg_toplevel::ResizeEdge) {
+        let Some(edge) = (match edges {
+            xdg_toplevel::ResizeEdge::Top => Some(srdwm_core::ResizeEdge::Top),
+            xdg_toplevel::ResizeEdge::Bottom => Some(srdwm_core::ResizeEdge::Bottom),
+            xdg_toplevel::ResizeEdge::Left => Some(srdwm_core::ResizeEdge::Left),
+            xdg_toplevel::ResizeEdge::Right => Some(srdwm_core::ResizeEdge::Right),
+            xdg_toplevel::ResizeEdge::TopLeft => Some(srdwm_core::ResizeEdge::TopLeft),
+            xdg_toplevel::ResizeEdge::TopRight => Some(srdwm_core::ResizeEdge::TopRight),
+            xdg_toplevel::ResizeEdge::BottomLeft => Some(srdwm_core::ResizeEdge::BottomLeft),
+            xdg_toplevel::ResizeEdge::BottomRight => Some(srdwm_core::ResizeEdge::BottomRight),
+            // `None` is a valid protocol value (the client leaves the edge
+            // unspecified) but `WindowManager::start_resize` needs one --
+            // there's nothing sensible to default it to that wouldn't be a
+            // guess, so this is a no-op rather than picking one.
+            _ => None,
+        }) else {
+            return;
+        };
+        if let Some(&id) = self.surface_to_id.get(surface.wl_surface()) {
+            let pos = crate::input::last_pointer_pos(self);
+            self.wm.borrow_mut().start_resize(id, edge, pos.x as i32, pos.y as i32);
+        }
+    }
+
+    /// `maximize_request`/`unmaximize_request`/`fullscreen_request`/
+    /// `unfullscreen_request`/`minimize_request` were all still smithay's
+    /// default no-op (or configure-only) implementations - found
+    /// investigating the `toggle_fullscreen` decoration bug above, by
+    /// checking what else routes through the same `WindowManager` calls
+    /// the titlebar-button click handlers in `input.rs` already use.
+    /// These five are the *client-initiated* equivalent of those clicks: a
+    /// client's own window-menu "Maximize", pressing F11, an HTML5 video
+    /// going fullscreen, or (for a client that negotiated client-side
+    /// decoration and draws its own titlebar, like Firefox) that titlebar's
+    /// own maximize button - all ask the compositor to actually perform
+    /// the state change via these requests rather than the compositor
+    /// noticing on its own. Left unimplemented, every one of them was a
+    /// silent no-op: the client's button did nothing, with no error and
+    /// nothing to suggest why, from any app that relies on this instead of
+    /// (or in addition to) a compositor-side keybinding.
+    fn maximize_request(&mut self, surface: ToplevelSurface) {
+        if let Some(&id) = self.surface_to_id.get(surface.wl_surface()) {
+            if !self.wm.borrow().window(id).is_some_and(|w| w.maximized) {
+                self.wm.borrow_mut().toggle_maximize(id);
+                self.sync_geometry(id);
+                crate::foreign_toplevel::send_state(self, id);
+            }
+        }
+        surface.send_configure();
+    }
+
+    fn unmaximize_request(&mut self, surface: ToplevelSurface) {
+        if let Some(&id) = self.surface_to_id.get(surface.wl_surface()) {
+            if self.wm.borrow().window(id).is_some_and(|w| w.maximized) {
+                self.wm.borrow_mut().toggle_maximize(id);
+                self.sync_geometry(id);
+                crate::foreign_toplevel::send_state(self, id);
+            }
+        }
+        surface.send_configure();
+    }
+
+    /// `_output` (the client's requested target output) is ignored --
+    /// single-seat, and every other fullscreen entry point (the titlebar
+    /// button, `srd.window.fullscreen()`) already fullscreens on whatever
+    /// monitor the window is already on, so this matches that instead of
+    /// introducing an output-aware fullscreen path only this one request
+    /// would use.
+    fn fullscreen_request(&mut self, surface: ToplevelSurface, _output: Option<WlOutput>) {
+        if let Some(&id) = self.surface_to_id.get(surface.wl_surface()) {
+            if !self.wm.borrow().is_fullscreen(id) {
+                // `redraw_decoration_buffer` first, same reason
+                // `set_decorated_from_mode` calls it before `sync_geometry`:
+                // fullscreen also flips `Window.decorated`, and dropping
+                // the decoration needs the buffer actually removed, not
+                // just left stale for `sync_geometry`'s own resize-only
+                // redraw check to skip.
+                self.wm.borrow_mut().toggle_fullscreen(id);
+                self.redraw_decoration_buffer(id);
+                self.sync_geometry(id);
+                crate::foreign_toplevel::send_state(self, id);
+            }
+        }
+        surface.send_configure();
+    }
+
+    fn unfullscreen_request(&mut self, surface: ToplevelSurface) {
+        if let Some(&id) = self.surface_to_id.get(surface.wl_surface()) {
+            if self.wm.borrow().is_fullscreen(id) {
+                self.wm.borrow_mut().toggle_fullscreen(id);
+                self.redraw_decoration_buffer(id);
+                self.sync_geometry(id);
+                crate::foreign_toplevel::send_state(self, id);
+            }
+        }
+        surface.send_configure();
+    }
 
-    fn grab(&mut self, _surface: PopupSurface, _seat: wl_seat::WlSeat, _serial: Serial) {}
+    /// No `send_configure` here, matching the pointer-driven
+    /// `TitlebarHit::Minimize` handler in `input.rs`: minimizing doesn't
+    /// change the window's own size, only whether it's currently shown, so
+    /// there's nothing new to tell the client about its own geometry.
+    fn minimize_request(&mut self, surface: ToplevelSurface) {
+        if let Some(&id) = self.surface_to_id.get(surface.wl_surface()) {
+            self.wm.borrow_mut().minimize_window(id);
+            crate::foreign_toplevel::send_state(self, id);
+        }
+    }
 
-    fn reposition_request(&mut self, _surface: PopupSurface, _positioner: PositionerState, _token: u32) {}
+    /// Was a bare no-op - no `send_configure` at all. Per xdg-shell,
+    /// `xdg_surface.configure` is required before a popup's first commit;
+    /// real toolkits (confirmed live: GTK4's Wayland backend) block that
+    /// commit in a synchronous roundtrip waiting for it, so every popup
+    /// hung its client forever. GTK4 implements tooltips *and*
+    /// `Gtk.Popover` as `xdg_popup`, so this fired on hovering almost any
+    /// widget with a tooltip - confirmed by a peer session's gdb backtrace
+    /// (blocked in `wl_display_dispatch_queue` under `gtk_widget_show`)
+    /// after AGS wedged.
+    ///
+    /// Geometry is `positioner.get_geometry()` un-constrained - no
+    /// on-screen clamping yet (`PositionerState::get_unconstrained_geometry`
+    /// needs a target rect in the parent's surface-local space, which is a
+    /// real follow-up, not this fix); an occasional popup placed near a
+    /// screen edge may render partly off it, which is cosmetic, not a hang.
+    fn new_popup(&mut self, surface: PopupSurface, positioner: PositionerState) {
+        surface.with_pending_state(|state| {
+            state.geometry = positioner.get_geometry();
+            state.positioner = positioner;
+        });
+        if surface.send_configure().is_err() {
+            return;
+        }
+        let _ = self.popups.track_popup(smithay::desktop::PopupKind::Xdg(surface));
+    }
+
+    /// Implicit grab + dismiss-on-outside-click. Previously believed
+    /// blocked on `CompState`'s `SeatHandler` associated types not
+    /// satisfying `PopupManager::grab_popup`'s `WaylandFocus +
+    /// From<PopupKind>` bound - rechecked while implementing
+    /// `move_request`/`resize_request` (same trait, adjacent methods) and
+    /// it turns out they already do: `KeyboardFocus`/`PointerFocus` are
+    /// both plain `WlSurface`, smithay provides `impl From<PopupKind> for
+    /// WlSurface` itself, and `WlSurface: From<WlSurface>` trivially. No
+    /// blocker ever existed by the time of this pass; the bound just
+    /// hadn't been rechecked since being noted as unmet.
+    ///
+    /// `self.seat.clone()` rather than resolving `_seat` (the client's
+    /// `wl_seat` resource) via `Seat::from_resource` - this compositor
+    /// only ever has the one seat, matching how `move_request`/
+    /// `resize_request` already ignore the same parameter.
+    fn grab(&mut self, surface: PopupSurface, _seat: wl_seat::WlSeat, serial: Serial) {
+        let popup = PopupKind::Xdg(surface);
+        let Ok(root) = find_popup_root_surface(&popup) else { return };
+        let seat = self.seat.clone();
+        let Ok(grab) = self.popups.grab_popup(root, popup, &seat, serial) else { return };
+        if let Some(keyboard) = seat.get_keyboard() {
+            keyboard.set_grab(self, PopupKeyboardGrab::new(&grab), serial);
+        }
+        if let Some(pointer) = seat.get_pointer() {
+            pointer.set_grab(self, PopupPointerGrab::new(&grab), serial, Focus::Keep);
+        }
+    }
+
+    fn reposition_request(&mut self, surface: PopupSurface, positioner: PositionerState, token: u32) {
+        surface.with_pending_state(|state| {
+            state.geometry = positioner.get_geometry();
+            state.positioner = positioner;
+        });
+        surface.send_repositioned(token);
+    }
 
     fn toplevel_destroyed(&mut self, surface: ToplevelSurface) {
         self.remove_window(surface.wl_surface());
@@ -99,14 +356,42 @@ impl XdgDecorationHandler for CompState {
         });
     }
 
-    fn request_mode(&mut self, toplevel: ToplevelSurface, _mode: DecorationMode) {
+    /// Honors whichever mode the client actually asked for, rather than
+    /// always forcing server-side - and mirrors the result into our own
+    /// `Window.decorated`, so a client drawing its own titlebar doesn't
+    /// *also* get one drawn on top of it by us.
+    ///
+    /// Always forcing `ServerSide` (what this used to do) is why some
+    /// clients ended up with two sets of window buttons: Firefox requests
+    /// client-side decoration when its own "use system titlebar" setting
+    /// is off, and draws its own close/minimize/maximize row regardless of
+    /// what the compositor grants - so forcing server-side just added
+    /// srdwm's row on top of the one Firefox was drawing anyway, instead
+    /// of preventing it. Respecting the request means srdwm steps out of
+    /// the way for exactly those clients, while everything that accepts
+    /// (or has no preference and gets offered) server-side still gets our
+    /// titlebar as before.
+    fn request_mode(&mut self, toplevel: ToplevelSurface, mode: DecorationMode) {
         toplevel.with_pending_state(|state| {
-            state.decoration_mode = Some(DecorationMode::ServerSide);
+            state.decoration_mode = Some(mode);
         });
         toplevel.send_configure();
+        self.set_decorated_from_mode(toplevel.wl_surface(), mode == DecorationMode::ServerSide);
     }
 
-    fn unset_mode(&mut self, _toplevel: ToplevelSurface) {}
+    /// The client dropped its decoration-mode preference. `new_decoration`
+    /// already offered `ServerSide` as the default the next configure will
+    /// carry, so mirror that same default here rather than leaving
+    /// whatever mode was negotiated before this - otherwise a client that
+    /// requests `ClientSide`, then later unsets it expecting the default
+    /// back, would stay undecorated by us forever.
+    fn unset_mode(&mut self, toplevel: ToplevelSurface) {
+        toplevel.with_pending_state(|state| {
+            state.decoration_mode = Some(DecorationMode::ServerSide);
+        });
+        toplevel.send_configure();
+        self.set_decorated_from_mode(toplevel.wl_surface(), true);
+    }
 }
 
 impl ShmHandler for CompState {
@@ -119,8 +404,167 @@ impl BufferHandler for CompState {
     fn buffer_destroyed(&mut self, _buffer: &WlBuffer) {}
 }
 
+impl DmabufHandler for CompState {
+    fn dmabuf_state(&mut self) -> &mut DmabufState {
+        &mut self.dmabuf_state
+    }
+
+    /// Validates a client's dmabuf by actually importing it wherever a
+    /// renderer is reachable from here, so a genuinely bad buffer (wrong
+    /// modifier, format the renderer doesn't support) gets the protocol
+    /// error instead of silently rendering garbage later.
+    ///
+    /// That's only the udev backend: its `PixmanRenderer` lives inside
+    /// `self.udev` (`UdevState`), a field of this same struct.
+    /// `PixmanRenderer` supports dmabuf import despite being a pure
+    /// software renderer - `dmabuf_formats()` only advertises the Linear
+    /// modifier, which it imports by mmap'ing the buffer and reading it
+    /// directly as pixels, no GPU involved. This is what actually answers
+    /// `docs/PANEL_SUPPORT_TODO.md`'s P0.3: GTK4 allocates via its own
+    /// EGL/gbm path against the real DRM render node (untouched by this
+    /// compositor either way) and hands the result here as a Linear-
+    /// modifier dmabuf, which pixman can read straight off.
+    ///
+    /// The winit (nested/dev) backend's `GlesRenderer` lives on
+    /// `WaylandPlatform`, a sibling of `CompState`, not reachable from a
+    /// method on `CompState` itself. Accepted there without eager
+    /// validation - the buffer still gets imported the same way every
+    /// other buffer type already is, lazily, the first time it is actually
+    /// rendered via `render_elements_from_surface_tree`. Real hardware,
+    /// where P0.3 actually bites, always goes through the udev path.
+    fn dmabuf_imported(&mut self, _global: &DmabufGlobal, dmabuf: Dmabuf, notifier: ImportNotifier) {
+        match self.udev.as_mut() {
+            Some(udev) => match udev.renderer.import_dmabuf(&dmabuf, None) {
+                Ok(_) => {
+                    let _ = notifier.successful::<CompState>();
+                }
+                Err(e) => {
+                    log::warn!("udev: rejecting dmabuf import: {e}");
+                    notifier.failed();
+                }
+            },
+            None => {
+                let _ = notifier.successful::<CompState>();
+            }
+        }
+    }
+}
+
+impl XdgActivationHandler for CompState {
+    fn activation_state(&mut self) -> &mut XdgActivationState {
+        &mut self.xdg_activation_state
+    }
+
+    /// A launcher spawns an app after first getting a token
+    /// (`get_activation_token`) and handing it to the new process (usually
+    /// via `XDG_ACTIVATION_TOKEN`); the app's own first window then
+    /// presents that same token back here via `activate`, asking to be
+    /// raised. Without this, that request was silently ignored - the new
+    /// window opened and just sat there unfocused behind everything,
+    /// exactly the gap `docs/PANEL_SUPPORT_TODO.md`'s P1 flagged.
+    ///
+    /// No token bookkeeping of our own: `token_created`'s default already
+    /// accepts every token (fine for a single-user session with no
+    /// cross-client trust boundary to enforce), so all that's left is
+    /// mapping the activating `surface` to a `WindowId` and reusing the
+    /// exact same `focus_window` path a dock's "activate" request already
+    /// goes through (`foreign_toplevel.rs`). If the surface isn't tracked
+    /// yet - the activation raced ahead of this window's own mapping --
+    /// there is nothing to focus yet, so this is a no-op rather than an
+    /// error; the protocol doesn't require honoring every activation.
+    fn request_activation(&mut self, _token: XdgActivationToken, _token_data: XdgActivationTokenData, surface: WlSurface) {
+        if let Some(&id) = self.surface_to_id.get(&surface) {
+            crate::input::focus_window(self, id);
+        }
+    }
+}
+
+/// `zwp_text_input_manager_v3` + `zwp_input_method_manager_v2`: lets a real
+/// input method (fcitx5, ibus, any CJK/dead-key/emoji-picker IME) attach to
+/// whichever surface has keyboard focus and draw its own candidate/
+/// composition popup. Without these two globals a client that only speaks
+/// text-input (most modern toolkits do, GTK4/Qt6 included) has no way to
+/// tell the compositor "I have an editable text field, here is its cursor
+/// rectangle" - every desktop app's search box, address bar, and chat
+/// input silently loses IME support, not just an edge case.
+///
+/// Focus tracking needs *no* wiring here at all: `CompState::KeyboardFocus`
+/// is a plain `WlSurface`, and smithay's own blanket `impl KeyboardTarget
+/// for WlSurface` already calls `seat.text_input().set_focus/.enter()/
+/// .leave()` and `seat.input_method().activate_input_method()/
+/// deactivate_input_method()` from inside `enter`/`leave` - which
+/// `set_keyboard_focus`'s existing `keyboard.set_focus(...)` call already
+/// triggers on every real focus change. The only things actually missing
+/// were the two manager globals and this handler for the popup surface
+/// lifecycle.
+impl smithay::wayland::input_method::InputMethodHandler for CompState {
+    /// A candidate/composition window (an emoji picker, a CJK candidate
+    /// list) just opened. Tracked as a regular [`PopupKind::InputMethod`]
+    /// in the same [`PopupManager`](smithay::desktop::PopupManager) that
+    /// already owns every `xdg_popup` - `elements::popup_render_elements`
+    /// renders both kinds identically, so no separate render path is
+    /// needed for this to actually become visible.
+    fn new_popup(&mut self, surface: ImePopupSurface) {
+        if let Err(e) = self.popups.track_popup(PopupKind::from(surface)) {
+            log::warn!("input-method: failed to track popup: {e}");
+        }
+    }
+
+    fn dismiss_popup(&mut self, surface: ImePopupSurface) {
+        if let Some(parent) = surface.get_parent().map(|p| p.surface.clone()) {
+            let _ = smithay::desktop::PopupManager::dismiss_popup(&parent, &PopupKind::from(surface));
+        }
+    }
+
+    /// The IME moved its own popup (e.g. following the text cursor as the
+    /// user types) - `PopupSurface::location()` already reflects the new
+    /// position; nothing else needs updating on this side, matching every
+    /// other smithay-based compositor's own no-op here.
+    fn popup_repositioned(&mut self, _surface: ImePopupSurface) {}
+
+    /// Where the IME should anchor its popup, in the parent surface's own
+    /// output-independent (logical, window-relative-origin) space - same
+    /// geometry `elements::popup_targets` already computes for xdg popups,
+    /// reused here rather than duplicated. A window not yet tracked (the
+    /// activation raced ahead of its own mapping) gets a default/zero rect,
+    /// same "no-op rather than an error" stance as `request_activation`
+    /// above.
+    fn parent_geometry(&self, parent: &WlSurface) -> smithay::utils::Rectangle<i32, smithay::utils::Logical> {
+        let Some(&id) = self.surface_to_id.get(parent) else {
+            return smithay::utils::Rectangle::default();
+        };
+        let wm = self.wm.borrow();
+        let Some(w) = wm.window(id) else {
+            return smithay::utils::Rectangle::default();
+        };
+        let band = if w.decorated { srdwm_core::TITLEBAR_HEIGHT as i32 } else { 0 };
+        smithay::utils::Rectangle::new((w.geometry.x, w.geometry.y + band).into(), (w.geometry.width as i32, w.geometry.height as i32).into())
+    }
+}
+
 impl smithay::wayland::output::OutputHandler for CompState {}
 
+/// `wp_cursor_shape_v1`: lets a client ask for a *named* cursor (text,
+/// grab, resize edges, ...) instead of rendering and attaching its own
+/// surface. Its requests route straight into `SeatHandler::cursor_image`
+/// below, same as a client-drawn cursor surface does - no extra state on
+/// our side. Without this global at all, a client that only speaks this
+/// (increasingly the norm - recent GTK4/Firefox use it for most cursor
+/// changes) has no way to tell us the pointer should look like anything
+/// but whatever it last was, which reads as the cursor going stale, wrong,
+/// or simply disappearing depending on what was showing when the client
+/// gave up trying.
+///
+/// `TabletSeatHandler` is a supertrait bound of this protocol's `Dispatch`
+/// impl (cursor-shape covers tablet tools too); srdwm has no tablet
+/// support to speak of, so every method is left at its no-op default.
+impl TabletSeatHandler for CompState {}
+
+/// Fractional scaling. srdwm runs every output at scale 1, so there is
+/// nothing to compute - but the global has to exist, because clients that
+/// use it (notably wallpaper daemons) treat it as mandatory.
+impl smithay::wayland::fractional_scale::FractionalScaleHandler for CompState {}
+
 impl SeatHandler for CompState {
     type KeyboardFocus = WlSurface;
     type PointerFocus = WlSurface;
@@ -145,6 +589,13 @@ impl WlrLayerShellHandler for CompState {
     }
 
     fn new_layer_surface(&mut self, surface: WlrLayerSurface, wl_output: Option<WlOutput>, _layer: Layer, namespace: String) {
+        // Logged before anything else can early-return or panic: the
+        // question this answers (see docs/PANEL_SUPPORT_TODO.md) is
+        // whether this handler is reached AT ALL for a later
+        // `get_layer_surface` request in a create -> commit -> destroy ->
+        // commit-again -> create sequence, or whether the client's
+        // dispatch is already dead by then and this never runs.
+        log::debug!("layer-shell: new_layer_surface entered, surface={:?} namespace={namespace:?} output_named={}", surface.wl_surface().id(), wl_output.is_some());
         // A client may name the output it wants (a bar on a specific
         // monitor); if it doesn't, or names one we don't drive, it lands on
         // the primary output.
@@ -157,14 +608,28 @@ impl WlrLayerShellHandler for CompState {
             log::warn!("wayland: layer surface requested but no output exists yet");
             return;
         };
+        // Paired with the debug log in `ensure_layer_initial_configure`'s
+        // early return - see docs/PANEL_SUPPORT_TODO.md's P0. This is the
+        // other half of "did map_layer actually succeed, and on which
+        // output": logged unconditionally (not just on the error paths
+        // that already existed) so a real reproduction shows both sides of
+        // the handoff instead of just the failure.
+        let surface_id = surface.wl_surface().id();
         let layer_surface = DesktopLayerSurface::new(surface, namespace);
         let result = layer_map_for_output(&output).map_layer(&layer_surface);
-        if let Err(e) = result {
-            log::warn!("wayland: failed to map layer surface: {e}");
+        match &result {
+            Ok(()) => log::debug!("layer-shell: mapped surface {surface_id:?} onto output {}", output.name()),
+            Err(e) => log::warn!("wayland: failed to map layer surface {surface_id:?}: {e}"),
         }
     }
 
     fn layer_destroyed(&mut self, surface: WlrLayerSurface) {
+        // See the matching top-of-function log in `new_layer_surface`.
+        log::debug!("layer-shell: layer_destroyed entered, surface={:?}", surface.wl_surface().id());
+        // Marks this surface for the pre-commit-hook workaround in
+        // `new_surface` - see that function's doc comment for the bug
+        // this exists to route around.
+        self.dead_layer_surfaces.insert(surface.wl_surface().clone());
         // The surface belongs to exactly one output's map, but which one is
         // the client's choice, so unmap from whichever holds it.
         for output in self.outputs().cloned().collect::<Vec<_>>() {
@@ -229,10 +694,44 @@ impl DataControlHandler for CompState {
     }
 }
 
+/// `ext_idle_notify_v1`. All the real logic (per-notification timers,
+/// resetting them on activity, honouring inhibition) already lives in
+/// smithay's own `IdleNotifierState` - this is just the getter it needs.
+/// See `input.rs`'s `notify_idle_activity` for the other half: nothing
+/// calls `notify_activity` on its own, that has to happen from every real
+/// input path.
+impl smithay::wayland::idle_notify::IdleNotifierHandler for CompState {
+    fn idle_notifier_state(&mut self) -> &mut smithay::wayland::idle_notify::IdleNotifierState<Self> {
+        &mut self.idle_notifier_state
+    }
+}
+
+/// `zwp_idle_inhibit_manager_v1`. A video player (or anything else that
+/// wants the screen to stay on/unlocked while it runs) creates one of
+/// these tied to its own surface; as long as at least one is alive,
+/// `IdleNotifierState::set_is_inhibited` stops idle timers from firing at
+/// all - see `idle_inhibiting_surfaces`'s doc comment on `CompState` for
+/// the one simplification (not workspace-visibility-aware) this takes.
+impl smithay::wayland::idle_inhibit::IdleInhibitHandler for CompState {
+    fn inhibit(&mut self, surface: WlSurface) {
+        self.idle_inhibiting_surfaces.push(surface);
+        self.idle_notifier_state.set_is_inhibited(true);
+    }
+
+    fn uninhibit(&mut self, surface: WlSurface) {
+        self.idle_inhibiting_surfaces.retain(|s| s != &surface);
+        self.idle_notifier_state.set_is_inhibited(!self.idle_inhibiting_surfaces.is_empty());
+    }
+}
+
 delegate_compositor!(CompState);
 delegate_xdg_shell!(CompState);
 delegate_xdg_decoration!(CompState);
 delegate_shm!(CompState);
+delegate_dmabuf!(CompState);
+delegate_xdg_activation!(CompState);
+delegate_text_input_manager!(CompState);
+delegate_input_method_manager!(CompState);
 delegate_seat!(CompState);
 delegate_output!(CompState);
 delegate_layer_shell!(CompState);
@@ -240,3 +739,8 @@ delegate_data_device!(CompState);
 delegate_primary_selection!(CompState);
 delegate_data_control!(CompState);
 delegate_session_lock!(CompState);
+delegate_cursor_shape!(CompState);
+smithay::delegate_viewporter!(CompState);
+smithay::delegate_fractional_scale!(CompState);
+smithay::delegate_idle_notify!(CompState);
+smithay::delegate_idle_inhibit!(CompState);