Scene/source builder with image overlays, reuse dialog, and SQLite layout persistence

ai.md

@@ -1,4 +1,4 @@
-# ytLive — AI Guide
+# ytLlive — AI Guide
 
 ## Run
 
@@ -21,8 +21,8 @@ C# / WPF (.NET 8) following MVVM:
 |------|------|
 | `Models/` | Plain data types — Scene, Source, StreamConfig, StreamHealth, YouTubeChannel, ChatMessage |
 | `ViewModels/` | MainViewModel — exposes collections + commands for the UI |
-| `Services/` | YouTube OAuth2, stream/broadcast management, live chat polling |
-| `Helpers/` | ViewModelBase (INotifyPropertyChanged), RelayCommand |
+| `Services/` | YouTube OAuth2, stream/broadcast management, live chat polling, LayoutStore (SQLite) |
+| `Helpers/` | ViewModelBase (INotifyPropertyChanged), RelayCommand, ImageCache |
 | `MainWindow.xaml` | Dark theme; layout: top bar (controls), center (preview), left (scenes/sources), right (chat), bottom (health) |
 
 ### Key patterns
@@ -31,15 +31,17 @@ C# / WPF (.NET 8) following MVVM:
 - `RelayCommand` for all button actions; commands gate on state (e.g. Start only when Offline)
 - ViewModels are constructed in XAML (`<vm:MainViewModel/>` as DataContext)
 - Services are currently instantiated in MainViewModel's constructor — no DI container yet
+- Layout persists to SQLite (`Microsoft.Data.Sqlite`); scenes/sources/asset bytes stored in the DB, asset identity is a SHA-256 content hash (1:M reuse, no file paths — assets are always available)
 
 ### Current limitations / TODOs
 
-- `YouTubeAuthService` constructor takes empty client ID/secret strings — needs Google Cloud credentials
-- `StartStream` is a stub (Task.Delay simulation)
-- `ConnectYouTube` is a stub
-- Preview panel is placeholder text
+- `OAuthCredentials.ClientId` / `ClientSecret` in `Helpers/OAuthCredentials.cs` are empty — the app
+  owner fills them in once (developer task, baked into the binary; creators never configure anything)
+- `GoLiveViewModel.SignIn`/`ChangeAccount` removed — Connect (OAuth) is the only entry to streaming
+- No token persistence yet (Windows DPAPI planned) — scene/source/asset layout *does* persist (SQLite)
+- `YouTubeStreamService` uses hardcoded `1080p`/`60fps` and per-broadcast streams — must switch to the v3 `variable` reusable stream
 - No capture/encoding/RTMP yet
-- No persistence layer (tokens, scenes, stream config all in-memory)
+- Stream config (title/description/visibility/quality) still in-memory
 
 ## Design Principle
 
@@ -51,9 +53,58 @@ Apply this to every UI decision:
 - Visual/drag-and-drop scene building over property panels
 - Every action produces a visible outcome — no dead ends
 
+## Monetization (design decision — the watermark is the sword)
+
+Free forever: all streams unlimited, no time caps, no subscription, no per-feature paywalls. The
+**one paid line is a one-time unlock** (delivered via itch.io — they handle hosting, payment, and key
+delivery; we never own a server or a key shop):
+
+- **Free:** a small "made with ytLlive" watermark is always on, every frame, every stream — the sword
+  of Damocles. Standard practice; only Streamlabs runs watermark-nagging to a capitalist extreme.
+- **Paid (one-time):** watermark removed + **Alerts** (Super Chat / membership / subscribe pop-ins).
+
+Deliberately rejected: hard stream-time cutoffs (the worst dead end — a stream dying mid-broadcast
+reads as broken, and YouTube streams routinely run 2-4 hours), soft-limit nagging, freemium tiers,
+and donation-only (relies on the kindness of strangers). Resolution/quality ceilings are **deferred** —
+that decision belongs to the resolution & streaming-constraints conversation, not monetization.
+
 ## Auth gates Go Live, but not exploration
 
 The app is fully usable without authentication: users can build scenes, add sources, compose
 previews, and audition the software with zero commitment. But **going live requires authentication** —
 it's the one capability gated behind YouTube sign-in. The sign-in button should never pressure the
 user ("sign in (optional)", not a modal wall), but "Go Live" only appears once connected.
+
+## Account assumption (do not build an account setup flow)
+
+Connecting uses Google OAuth ("Sign in with Google") to link an **existing** YouTube creator
+account. ytLlive **never creates or sets up accounts** — that is YouTube's job. If the creator has no
+YouTube channel, they go to YouTube first. This assumption is explicit and must never be silently
+replaced by an in-app account-creation step. Zero state = a Connect button that starts OAuth; going
+live is unreachable until the account is connected.
+
+## YouTube Live API — design constraints (do not violate)
+
+These are the hard facts behind every decision. Full list in `TASKS.md`.
+
+- **One-click go-live** — never call `transition(live)`. Insert the broadcast with
+  `enableAutoStart=true`, `enableAutoStop=true`, `enableMonitorStream=false`,
+  `selfDeclaredMadeForKids=false`, `latencyPreference=low`. The encoder starting brings YouTube live.
+  `enableMonitorStream=false` is what lets us skip the testing stage.
+- **Variable reusable stream** — `liveStreams.insert` once per channel with
+  `cdn.resolution=variable`, `cdn.frameRate=variable`, `isReusable=true`; cache the ingestion URL +
+  stream name and reuse for every broadcast. Any quality tier works without recreating the stream,
+  and auto step-down is done by us dropping bitrate on the fly (zero API calls).
+- **Quality is greyed out while live** — resolution/frameRate/ingestionType are immutable after
+  stream creation; editing title/description/privacy is fine at any time.
+- **Report-by-exception health** — poll `liveStreams.list`; render nothing on `good`/`ok`, surface a
+  banner only on `configurationIssues[]` with `warning`/`error` severity. Bottom strip = YouTube logo
+  + green/red connection dot (clickable → opens the dialog).
+- **One dialog, three states** — not connected / connected-offline (all editable) / live
+  (title + description + visibility editable; quality + account greyed out). Both entry points
+  (Start Stream button + bottom strip) open it; prefilled from saved session profile.
+- **End stream** — stop encoder → `transition(complete)`, `enableAutoStop` as the safety net.
+- **Encoder compliance** — keyframes ≤ 4s (gopSizeLong), closed GOP, H.264, AAC/MP3 @ 44.1/48kHz,
+  mono/stereo only. YouTube flags violations via health status.
+- **Broadcast ID == Video ID** — one ID tracks status, health, and the auto-created VOD
+  (`recordFromStart` + `enableDvr` default true).