From 71b44521ef84fafd5c4bb7c7905b68c3bc7542ad Mon Sep 17 00:00:00 2001
From: Brad Stein <Brad.Stein@gmail.com>
Date: Sun, 26 Apr 2026 12:42:17 -0300
Subject: [PATCH] fix(sync): refresh playout budget after pairing

---
 Cargo.lock                                 |  6 ++---
 client/Cargo.toml                          |  2 +-
 common/Cargo.toml                          |  2 +-
 server/Cargo.toml                          |  2 +-
 server/src/upstream_media_runtime.rs       |  9 +++++--
 server/src/upstream_media_runtime/tests.rs | 28 ++++++++++++++++++++++
 6 files changed, 41 insertions(+), 8 deletions(-)

diff --git a/Cargo.lock b/Cargo.lock
index 0d4045c..5d4b999 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1642,7 +1642,7 @@ checksum = "09edd9e8b54e49e587e4f6295a7d29c3ea94d469cb40ab8ca70b288248a81db2"
 
 [[package]]
 name = "lesavka_client"
-version = "0.14.1"
+version = "0.14.2"
 dependencies = [
  "anyhow",
  "async-stream",
@@ -1676,7 +1676,7 @@ dependencies = [
 
 [[package]]
 name = "lesavka_common"
-version = "0.14.1"
+version = "0.14.2"
 dependencies = [
  "anyhow",
  "base64",
@@ -1688,7 +1688,7 @@ dependencies = [
 
 [[package]]
 name = "lesavka_server"
-version = "0.14.1"
+version = "0.14.2"
 dependencies = [
  "anyhow",
  "base64",
diff --git a/client/Cargo.toml b/client/Cargo.toml
index 2b42fca..53f79cb 100644
--- a/client/Cargo.toml
+++ b/client/Cargo.toml
@@ -4,7 +4,7 @@ path                    = "src/main.rs"
 
 [package]
 name                    = "lesavka_client"
-version                 = "0.14.1"
+version                 = "0.14.2"
 edition                 = "2024"
 
 [dependencies]
diff --git a/common/Cargo.toml b/common/Cargo.toml
index 7922c62..2a2473e 100644
--- a/common/Cargo.toml
+++ b/common/Cargo.toml
@@ -1,6 +1,6 @@
 [package]
 name                    = "lesavka_common"
-version                 = "0.14.1"
+version                 = "0.14.2"
 edition                 = "2024"
 build                   = "build.rs"
 
diff --git a/server/Cargo.toml b/server/Cargo.toml
index 78b123c..c57ee84 100644
--- a/server/Cargo.toml
+++ b/server/Cargo.toml
@@ -10,7 +10,7 @@ bench                   = false
 
 [package]
 name                    = "lesavka_server"
-version                 = "0.14.1"
+version                 = "0.14.2"
 edition                 = "2024"
 autobins                = false
 
diff --git a/server/src/upstream_media_runtime.rs b/server/src/upstream_media_runtime.rs
index f4d1204..5893ef0 100644
--- a/server/src/upstream_media_runtime.rs
+++ b/server/src/upstream_media_runtime.rs
@@ -326,6 +326,7 @@ impl UpstreamMediaRuntime {
         let pairing_deadline = *state
             .pairing_anchor_deadline
             .get_or_insert_with(|| now + upstream_playout_delay());
+        let playout_delay = upstream_playout_delay();
 
         if state.session_base_remote_pts_us.is_none() {
             if state.first_camera_remote_pts_us.is_some()
@@ -337,7 +338,9 @@ impl UpstreamMediaRuntime {
                     state.first_microphone_remote_pts_us.unwrap_or_default();
                 state.session_base_remote_pts_us =
                     Some(first_camera_remote_pts_us.max(first_microphone_remote_pts_us));
-                state.playout_epoch = Some(pairing_deadline);
+                let overlap_epoch = now + playout_delay;
+                state.playout_epoch = Some(overlap_epoch);
+                state.pairing_anchor_deadline = Some(overlap_epoch);
                 if !state.startup_anchor_logged {
                     let startup_delta_us =
                         first_camera_remote_pts_us as i128 - first_microphone_remote_pts_us as i128;
@@ -377,7 +380,9 @@ impl UpstreamMediaRuntime {
                         .unwrap_or(remote_pts_us),
                 };
                 state.session_base_remote_pts_us = Some(single_stream_base_remote_pts_us);
-                state.playout_epoch = Some(pairing_deadline);
+                let one_sided_epoch = now + playout_delay;
+                state.playout_epoch = Some(one_sided_epoch);
+                state.pairing_anchor_deadline = Some(one_sided_epoch);
                 info!(
                     session_id,
                     ?kind,
diff --git a/server/src/upstream_media_runtime/tests.rs b/server/src/upstream_media_runtime/tests.rs
index 5b1deea..480ed8f 100644
--- a/server/src/upstream_media_runtime/tests.rs
+++ b/server/src/upstream_media_runtime/tests.rs
@@ -339,6 +339,34 @@ fn catastrophic_lateness_reanchors_the_shared_playout_epoch() {
     });
 }
 
+#[test]
+fn overlap_anchor_gets_a_fresh_playout_budget_when_pairing_finishes_late() {
+    temp_env::with_var("LESAVKA_UPSTREAM_PLAYOUT_DELAY_MS", Some("20"), || {
+        let runtime = UpstreamMediaRuntime::new();
+        let _camera = runtime.activate_camera();
+        let _microphone = runtime.activate_microphone();
+
+        assert!(matches!(
+            runtime.plan_video_pts(1_000_000, 16_666),
+            super::UpstreamPlanDecision::AwaitingPair
+        ));
+
+        std::thread::sleep(Duration::from_millis(15));
+        let before_pair = tokio::time::Instant::now();
+        let audio_first = play(runtime.plan_audio_pts(1_000_000));
+        let video_first = play(runtime.plan_video_pts(1_000_000, 16_666));
+
+        assert!(
+            audio_first.due_at.saturating_duration_since(before_pair) >= Duration::from_millis(15),
+            "audio should keep most of the configured playout budget after late pairing"
+        );
+        assert!(
+            video_first.due_at.saturating_duration_since(before_pair) >= Duration::from_millis(15),
+            "video should keep most of the configured playout budget after late pairing"
+        );
+    });
+}
+
 #[test]
 fn catastrophic_lateness_reanchors_only_once_per_session() {
     temp_env::with_var("LESAVKA_UPSTREAM_PLAYOUT_DELAY_MS", Some("20"), || {