seat: implement per-device keymaps

jay-config/src/_private/client.rs

@@ -818,6 +818,10 @@ impl Client {
         self.send(&ClientMessage::SetSeat { device, seat })
     }
 
+    pub fn set_device_keymap(&self, device: InputDevice, keymap: Keymap) {
+        self.send(&ClientMessage::DeviceSetKeymap { device, keymap })
+    }
+
     pub fn set_left_handed(&self, device: InputDevice, left_handed: bool) {
         self.send(&ClientMessage::SetLeftHanded {
             device,

jay-config/src/_private/ipc.rs

@@ -432,6 +432,10 @@ pub enum ClientMessage<'a> {
         enabled: bool,
     },
     GetSocketPath,
+    DeviceSetKeymap {
+        device: InputDevice,
+        keymap: Keymap,
+    },
 }
 
 #[derive(Serialize, Deserialize, Debug)]

jay-config/src/input.rs

@@ -25,6 +25,16 @@ impl InputDevice {
         get!().set_seat(self, seat)
     }
 
+    /// Sets the keymap of the device.
+    ///
+    /// This overrides the keymap set for the seat. The keymap becomes active when a key
+    /// on the device is pressed.
+    ///
+    /// Setting the invalid keymap reverts to the seat keymap.
+    pub fn set_keymap(self, keymap: Keymap) {
+        get!().set_device_keymap(self, keymap)
+    }
+
     /// Returns whether the device has the specified capability.
     pub fn has_capability(self, cap: Capability) -> bool {
         get!(false).has_capability(self, cap)