feat: manage multiple ssh machines from one client (#3670)

1 files changed, 86 insertions, 0 deletions

diff --git a/src/server/headless/surface_interest.rs b/src/server/headless/surface_interest.rs
new file mode 100644
index 00000000..7270be0d
--- /dev/null
+++ b/src/server/headless/surface_interest.rs
@@ -0,0 +1,86 @@
+use super::*;
+
+impl HeadlessServer {
+    /// Apply a client-shell surface lease and return the resulting projection floor.
+    ///
+    /// Every `active: true` request advances the floor, even if the server already considered
+    /// the connection active. That makes a new client activation epoch distinguishable from a
+    /// delayed same-boot PaneSurface that was prepared for an earlier epoch.
+    pub(super) fn set_client_shell_surface_active(
+        &mut self,
+        client_id: u64,
+        active: bool,
+    ) -> Option<(bool, u64)> {
+        let focus_before = self.shell_focus_targets();
+        let focused_tabs_before = self.focused_shell_tabs();
+        let (changed, projection_revision) = {
+            let client = self.clients.get_mut(&client_id)?;
+            if !client.is_shell_client() {
+                return None;
+            }
+            let changed = client.shell_surface_active != active;
+            if active {
+                client.shell_projection_revision =
+                    client.shell_projection_revision.saturating_add(1);
+                // Force the next control snapshot to carry this new floor instead of reusing a
+                // same-boot cached snapshot from the prior surface epoch.
+                client.shell_snapshot = None;
+            }
+            if !changed && !active {
+                return Some((false, client.shell_projection_revision));
+            }
+            client.shell_surface_active = active;
+            client.request_repaint();
+            client.shell_graphics_delivery = Default::default();
+            // The client drops target effects while its old source frame is frozen. Reset the
+            // dedupe state whenever a viewer is (re)activated so the post-commit replay can
+            // produce mouse/keyboard modes and graphics even when runtime demand is unchanged.
+            if active {
+                client.host_mouse_capture_active = None;
+                client.host_sgr_pixels_active = None;
+                client.host_keyboard_report_all_active = None;
+            }
+            client.clear_deferred_render();
+            if !active {
+                if let Some(writer) = &client.writer {
+                    writer.discard_pending_render();
+                }
+            }
+            (changed, client.shell_projection_revision)
+        };
+        let held_inputs = (!active && changed).then(|| {
+            self.clients
+                .get_mut(&client_id)
+                .expect("checked client")
+                .drain_shell_held_inputs()
+        });
+
+        if let Some(held_inputs) = held_inputs {
+            self.release_client_shell_inputs(client_id, held_inputs);
+            self.retire_direct_graphics_for_client(client_id);
+        }
+        if changed {
+            self.finish_shell_location_reconciliation(focus_before, &focused_tabs_before);
+        }
+
+        if active {
+            self.promote_client_to_foreground(client_id);
+            // Do not emit/cache a title during a frozen target activation. A committed client
+            // explicitly requests the bounded replay after its coherent frame is visible.
+            self.sent_window_title = None;
+            self.resize_shared_runtime_to_effective_size_with_pending_agent_resumes(true);
+            self.claim_shell_tab_geometry(client_id, true);
+        } else {
+            self.tab_geometry_controllers
+                .retain(|_, controller_id| *controller_id != client_id);
+            if self.foreground_client_id == Some(client_id) {
+                self.promote_latest_remaining_client();
+                self.resize_shared_runtime_to_effective_size_with_pending_agent_resumes(true);
+            } else {
+                self.sync_foreground_client_state();
+            }
+            self.reapply_controlled_shell_tab_geometry(true);
+        }
+        Some((changed || active, projection_revision))
+    }
+}