x11: add nested x11 backend

src/state.rs

@@ -1,19 +1,44 @@
 // SPDX-License-Identifier: GPL-3.0-only
 
-use std::{cell::RefCell, rc::Rc};
-
-use smithay::reexports::wayland_server::Display;
+use crate::backend::x11::X11State;
+use smithay::{desktop::Space, reexports::wayland_server::Display};
+use std::{cell::RefCell, rc::Rc, time::Instant};
 
 pub struct State {
     pub display: Rc<RefCell<Display>>,
+    pub spaces: Space, //TODO: Multiple workspaces
+
+    pub start_time: Instant,
     pub should_stop: bool,
+    pub backend: BackendData,
+}
+
+pub enum BackendData {
+    X11(X11State),
+    // TODO
+    // Wayland(WaylandState),
+    // Udev(UdevState),
+    Unset,
+}
+
+impl BackendData {
+    pub fn x11(&mut self) -> &mut X11State {
+        match self {
+            BackendData::X11(ref mut x11_state) => x11_state,
+            _ => unreachable!("Called x11 in non x11 backend"),
+        }
+    }
 }
 
 impl State {
     pub fn new(display: Display) -> State {
         State {
             display: Rc::new(RefCell::new(display)),
+            spaces: Space::new(slog_scope::logger() /*TODO*/),
+
+            start_time: Instant::now(),
             should_stop: false,
+            backend: BackendData::Unset,
         }
     }
 }