WIP: Enable necessary protocols for supporting IMEs

I'm not entirely sure how text input focus should be managed:
Smithay/smithay#1038.

This "works" but is missing a bit of code to actually render the IME
surface, and the code in anvil calling `set_point` (I'm not sure exactly
what that is for or where/how it should be set here).

src/state.rs

@@ -53,14 +53,17 @@ use smithay::{
         compositor::{CompositorClientState, CompositorState},
         data_device::DataDeviceState,
         dmabuf::{DmabufFeedback, DmabufState},
+        input_method::InputMethodManagerState,
         keyboard_shortcuts_inhibit::KeyboardShortcutsInhibitState,
         output::OutputManagerState,
         presentation::PresentationState,
         primary_selection::PrimarySelectionState,
         seat::WaylandFocus,
         shell::{kde::decoration::KdeDecorationState, xdg::decoration::XdgDecorationState},
         shm::ShmState,
+        text_input::TextInputManagerState,
         viewporter::ViewporterState,
+        virtual_keyboard::VirtualKeyboardManagerState,
     },
 };
 use tracing::error;
@@ -261,6 +264,9 @@ impl State {
         let wl_drm_state = WlDrmState;
         let kde_decoration_state = KdeDecorationState::new::<Self>(&dh, Mode::Client);
         let xdg_decoration_state = XdgDecorationState::new::<Self>(&dh);
+        InputMethodManagerState::new::<Self>(&dh);
+        TextInputManagerState::new::<Self>(&dh);
+        VirtualKeyboardManagerState::new::<State, _>(&dh, |_client| true);
 
         let shell = Shell::new(&config, dh);
 

src/wayland/handlers/input_method.rs

@@ -0,0 +1,9 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
+// TODO: Restrict what applications can use protocol? At least don't allow in
+// sandboxed app.
+
+use crate::state::State;
+use smithay::delegate_input_method_manager;
+
+delegate_input_method_manager!(State);

src/wayland/handlers/mod.rs

@@ -5,6 +5,7 @@ pub mod compositor;
 pub mod data_device;
 pub mod decoration;
 pub mod dmabuf;
+pub mod input_method;
 pub mod keyboard_shortcuts_inhibit;
 pub mod layer_shell;
 pub mod output;
@@ -15,9 +16,11 @@ pub mod relative_pointer;
 pub mod screencopy;
 pub mod seat;
 pub mod shm;
+pub mod text_input;
 pub mod toplevel_info;
 pub mod toplevel_management;
 pub mod viewporter;
+pub mod virtual_keyboard;
 pub mod wl_drm;
 pub mod workspace;
 pub mod xdg_shell;

src/wayland/handlers/seat.rs

@@ -10,7 +10,7 @@ use smithay::{
     reexports::wayland_server::Resource,
     wayland::{
         data_device::set_data_device_focus, primary_selection::set_primary_focus,
-        seat::WaylandFocus,
+        seat::WaylandFocus, text_input::TextInputHandle,
     },
 };
 use std::cell::RefCell;
@@ -46,7 +46,12 @@ impl SeatHandler for State {
             .and_then(|s| dh.get_client(s.id()).ok())
         {
             set_data_device_focus(dh, seat, Some(client.clone()));
-            set_primary_focus(dh, seat, Some(client))
+            set_primary_focus(dh, seat, Some(client));
+
+            if let Some(text_input) = seat.user_data().get::<TextInputHandle>() {
+                let surface = focused.and_then(WaylandFocus::wl_surface);
+                text_input.set_focus(surface.as_ref(), || {});
+            }
         }
     }
 }

src/wayland/handlers/text_input.rs

@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
+use crate::state::State;
+use smithay::delegate_text_input_manager;
+
+delegate_text_input_manager!(State);

src/wayland/handlers/virtual_keyboard.rs

@@ -0,0 +1,6 @@
+// SPDX-License-Identifier: GPL-3.0-only
+
+use crate::state::State;
+use smithay::delegate_virtual_keyboard_manager;
+
+delegate_virtual_keyboard_manager!(State);