output_configuration: Allow setting xwayland primary output

src/wayland/handlers/output_configuration.rs

@@ -6,6 +6,7 @@ use tracing::{error, warn};
 use crate::{
     config::{OutputConfig, OutputState},
     state::State,
+    utils::prelude::OutputExt,
     wayland::protocols::output_configuration::{
         delegate_output_configuration, ModeConfiguration, OutputConfiguration,
         OutputConfigurationHandler, OutputConfigurationState,
@@ -25,6 +26,17 @@ impl OutputConfigurationHandler for State {
     fn apply_configuration(&mut self, conf: Vec<(Output, OutputConfiguration)>) -> bool {
         self.output_configuration(false, conf)
     }
+
+    fn request_xwayland_primary(&mut self, primary_output: Option<Output>) {
+        for output in self.common.output_configuration_state.outputs() {
+            output.config_mut().xwayland_primary =
+                primary_output.as_ref().is_some_and(|o| *o == output);
+        }
+        self.common.update_xwayland_primary_output();
+        self.common
+            .config
+            .write_outputs(self.common.output_configuration_state.outputs());
+    }
 }
 
 impl State {

src/wayland/protocols/output_configuration/handlers/cosmic.rs

@@ -21,7 +21,7 @@ use cosmic_protocols::output_management::v1::server::{
     zcosmic_output_manager_v1::{self, ZcosmicOutputManagerV1},
 };
 
-use crate::wayland::protocols::output_configuration::*;
+use crate::{config::OutputState as EnabledState, wayland::protocols::output_configuration::*};
 
 impl<D> GlobalDispatch<ZcosmicOutputManagerV1, OutputMngrGlobalData, D>
     for OutputConfigurationState<D>
@@ -109,6 +109,25 @@ where
             } => {
                 data_init.init(extended, config_head.downgrade());
             }
+            zcosmic_output_manager_v1::Request::SetXwaylandPrimary { head } => {
+                let Some(head) = head else {
+                    state.request_xwayland_primary(None);
+                    return;
+                };
+
+                let inner = state.output_configuration_state();
+                if let Some(head_data) = inner.instances.iter_mut().find_map(|instance| {
+                    instance
+                        .heads
+                        .iter()
+                        .find(|instance| instance.extension_obj.as_ref() == Some(&head))
+                }) {
+                    let output = head_data.output.clone();
+                    if output.config().enabled == EnabledState::Enabled {
+                        state.request_xwayland_primary(Some(output));
+                    }
+                }
+            }
             _ => {}
         }
     }

src/wayland/protocols/output_configuration/mod.rs

@@ -58,6 +58,8 @@ pub trait OutputConfigurationHandler: Sized {
 
     fn test_configuration(&mut self, conf: Vec<(Output, OutputConfiguration)>) -> bool;
     fn apply_configuration(&mut self, conf: Vec<(Output, OutputConfiguration)>) -> bool;
+
+    fn request_xwayland_primary(&mut self, output: Option<Output>);
 }
 
 pub struct OutputMngrGlobalData {
@@ -189,7 +191,7 @@ where
         );
 
         let extension_global = dh.create_global::<D, ZcosmicOutputManagerV1, _>(
-            2,
+            3,
             OutputMngrGlobalData {
                 filter: Box::new(client_filter),
             },
@@ -505,6 +507,14 @@ where
             instance.obj.model(physical.model);
         }
     }
+
+    if let Some(extension_obj) = instance.extension_obj.as_ref() {
+        if inner.enabled
+            && extension_obj.version() >= zcosmic_output_head_v1::EVT_XWAYLAND_PRIMARY_SINCE
+        {
+            extension_obj.xwayland_primary(output.config().xwayland_primary as u32);
+        }
+    }
 }
 
 fn remove_global_with_timer<D: 'static>(

src/xwayland.rs

@@ -652,9 +652,12 @@ impl Common {
             if let Some(xwm) = xstate.xwm.as_mut() {
                 if let Err(err) = xwm.set_randr_primary_output(xwayland_primary_output.as_ref()) {
                     warn!("Failed to set xwayland primary output: {}", err);
+                    return;
                 };
             }
         }
+
+        self.output_configuration_state.update();
     }
 }