# HANDOFF — Session State

## Branch / Commit State

**`main`**, working toward TASK 22 (audio sync offset). Prior milestone **TASK 31**
(SceneGraph + baked-crust compositor) is fully done, committed (`670fe3a`), pushed
(`origin/main` `3bf053a..670fe3a`), and verified by the user on native Windows
PowerShell (only the 2 known pre-existing failures remained).

## What's In Flight

**TASK 22 (audio sync offset) — implemented, uncommitted, awaiting commit + user
verification on Windows.**

Scope (Good-Dog single use-case; user chose positive-only slider at the mixer out):
a global `AudioSyncOffsetMs` (0..500 ms, default 0) that delays the whole
interleaved-stereo mix so audio lands on the video when it runs ahead — OBS's
documented lip-sync fix. Positive-only: advancing audio needs a video-side delay
(out of the audio layer's scope; tracked for v1.1).

Files touched (this work unit):
- `Services/Audio/AudioSyncDelay.cs` (new) — pure delay line, flushed on `Configure`.
- `Services/Audio/AudioMixer.cs` — `Func<int> syncOffsetMs` seam + `_syncDelay`
  applied post-limiter in `FillAndMix`.
- `Services/LayoutStore.Settings.cs` — `LoadAudioSyncOffsetMs`/`SaveAudioSyncOffsetMs`
  (`Audio.SyncOffsetMs`).
- `ViewModels/MainViewModel.cs` — load offset at startup + save in `SaveLayoutNow`.
- `ViewModels/MainViewModel.Audio.cs` — `AudioSyncOffsetMs` property (clamped, `ScheduleSave`).
- `Controls/PreviewPane.xaml` — SYNC slider (0..500) + status dot on the mic bar.
- `Helpers/IntToSyncBrushConverter.cs` (new) + registered in `Themes/Controls.xaml`.
- `ytLive.Tests/AudioSyncDelayTests.cs` (new) — 3 tests.
- `ai.md`, `TASKS.md`, `HANDOFF.md`.

**Verified:** `ytLive.csproj` and `ytLive.Tests.csproj` build with 0 warnings;
`AudioSyncDelayTests` (3/3) pass via vstest filter. The full audio pipeline /
RealAppHost suites hang headless (pre-existing) — must be verified on native
Windows PowerShell by the user.

**Landmine:** a stale `testhost` can lock `ytLive.Tests`'s `ytLive.dll` and break
`dotnet build` of the test project — kill it first (`cmd.exe /c "taskkill /PID N /F"`)
if the build hits MSB3027.

## Next

1. User runs `scripts/verify.sh` (or native Windows vstest) to confirm the full
   suite — expect only the 2 known pre-existing failures.
2. On confirmation, run `scripts/scope-check.sh` with the declared file list,
   commit as one work unit, await the user's push go-ahead (sub-milestone).

## The directive (2026-08-31, user)

Rewrite the project into functional components to aid AI retrieval — the
`Services/ChatOverlayLayer.cs` style (owner-state extraction), not line-count
chasing. TASK 31's `SceneGraph.cs` continued that pattern (an owner object owning
the scene collection + mutation surface).