config: add keyboard-focus window criteria

jay-config/src/_private.rs

@@ -6,6 +6,7 @@ pub(crate) mod string_error;
 use {
     crate::{
         client::ClientMatcher,
+        input::Seat,
         video::Mode,
         window::{WindowMatcher, WindowType},
     },
@@ -113,6 +114,7 @@ pub enum WindowCriterionIpc {
     Floating,
     Visible,
     Urgent,
+    SeatFocus(Seat),
 }
 
 #[derive(Serialize, Deserialize, Clone, Debug, Hash, Eq, PartialEq)]

jay-config/src/_private/client.rs

@@ -1660,6 +1660,7 @@ impl ConfigClient {
             WindowCriterion::Floating => WindowCriterionIpc::Floating,
             WindowCriterion::Visible => WindowCriterionIpc::Visible,
             WindowCriterion::Urgent => WindowCriterionIpc::Urgent,
+            WindowCriterion::Focus(seat) => WindowCriterionIpc::SeatFocus(seat),
         };
         let res = self.send_with_response(&ClientMessage::CreateWindowMatcher { criterion });
         get_response!(

jay-config/src/window.rs

@@ -4,6 +4,7 @@ use {
     crate::{
         Axis, Direction, Workspace,
         client::{Client, ClientCriterion},
+        input::Seat,
     },
     serde::{Deserialize, Serialize},
     std::ops::Deref,
@@ -250,6 +251,8 @@ pub enum WindowCriterion<'a> {
     Visible,
     /// Matches if the window has the urgency flag set.
     Urgent,
+    /// Matches if the window has the keyboard focus of the seat.
+    Focus(Seat),
 }
 
 impl WindowCriterion<'_> {