# ytLlive — AI Guide
> Memory map entry point. Conventions live in [`schema.md`](schema.md); task
> status and YouTube API research in [`TASKS.md`](TASKS.md); directory maps in
> each folder's `index.md`. Reading order: this file → `TASKS.md` → `
/index.md` → source.
## Response style
No default "Plans & Pitfalls" / planning boilerplate. Respond directly and
concisely: **do the queued work, then report what changed and what's next.**
Skip feature pitch, step-by-step implementation plans, pros/cons tables, and
"potential pitfalls" sections unless the user explicitly asks for a plan first.
A short diff-style summary beats a proposal document every time.
### No-Fluff Mode (on demand)
Invoke with "no-fluff mode" (or similar) when you want ruthless review instead
of reassurance. In that mode:
- Strip all polite pleasantries, emojis, transitions, and conversational padding.
- Treat the user's input as a draft to be methodically deconstructed or
strengthened — argue, correct, and sharpen rather than agree.
- Give unvarnished truth, not reassurance.
This is an occasional, explicitly-invoked mode — **never the default**. The
default response style above stays in effect unless invoked.
## Run
```bash
dotnet build # Windows only — WPF requires Windows target
dotnet run
```
Note: `EnableWindowsTargeting=true` is set in `ytLive.csproj`, so the project can be restored/built from WSL, but running requires Windows.
## Tests
No test framework set up yet. When added: `dotnet test`.
## Architecture
C# / WPF (.NET 8) following MVVM:
| Path | Role |
|------|------|
| `Models/` | Plain data types — Scene, Source, QualityOption, StreamConfig, StreamHealth, YouTubeChannel, ChatMessage |
| `ViewModels/` | MainViewModel — exposes collections + commands for the UI; GoLiveViewModel, ReuseImageViewModel |
| `Services/` | YouTube OAuth2, stream/broadcast management, live chat polling, LayoutStore (SQLite) |
| `Helpers/` | ViewModelBase (INotifyPropertyChanged), RelayCommand, ImageCache, AppLog (file logger), FocusPreservingListBox, OAuthCredentials, visibility converters |
| `Themes/` | `Controls.xaml` — the single dark-theme source, merged once in `App.xaml` (see `Themes/index.md`) |
| `MainWindow.xaml` | Dark theme; layout: top bar (controls), center (preview), left (scenes/sources), right (chat), bottom (health) |
### Key patterns
- `ViewModelBase.SetProperty()` for property change notifications
- `RelayCommand` for all button actions; commands gate on state (e.g. Start only when Offline)
- ViewModels are constructed in XAML (`` 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)
- Theming: all custom styles live in `Themes/Controls.xaml`, merged in `App.xaml` — never duplicate styles per-window (dialog duplicates were consolidated into this dictionary)
- Resolution tiers (bottom bar): 1080p60@8 → 1080p30@8 → 720p60@6 → 480p30@2.5 Mbps; default = first. A **tooltip** explains finding upload bandwidth — an in-app speed test was deliberately dropped (unreliable)
- Crash diagnosis: `AppLog` writes startup checkpoints to `%APPDATA%\ytLlive\startup.log`; `App.xaml.cs` logs `DispatcherUnhandledException`/`AppDomain.UnhandledException`. When WPF won't run from WSL, this log is how you find the failure (it caught the `MenuItemRole.Separator` XAML crash and the ComboBox SelectionBoxItem bug)
### Current limitations / TODOs
- `Helpers/OAuthCredentials.cs` now contains the real ClientId/ClientSecret — auth service is implemented, but **tokens still don't persist** (Windows DPAPI planned; account UI in the GoLive dialog is simulated)
- `GoLiveViewModel.SignIn`/`ChangeAccount` removed — Connect (OAuth) is the only entry to streaming
- Scene/source/asset layout *does* persist (SQLite); token persistence does not (yet)
- `YouTubeStreamService` uses hardcoded `1080p`/`60fps` and per-broadcast streams — must switch to the v3 `variable` reusable stream
- No capture/encoding/RTMP yet
- `StreamConfig` defaults (`TargetBitrate=6000`, `Resolution="1920x1080"`) are stale — the live dropdown drives `StreamHealth.CurrentBitrate`/`FPS` instead
## Design Principle
> This software is so intuitive that even the most right-brained person can easily intuit and use it.
Apply this to every UI decision:
- One-click go-live with working defaults
- Prefilled YouTube defaults (RTMP URL, bitrate, resolution, latency)
- Visual/drag-and-drop scene building over property panels
- Every action produces a visible outcome — no dead ends
## Monetization (design decision — the branding flash 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 periodic full-frame branding flash — "made with ytLlive!" rendered big and centered at
~25% opacity for about one second (soft 250ms fade in/out), repeated every 300s, on the live output
(and on v0.2 local recordings). Implemented as `BrandFlashLayer` in the preview compositor
(`MainWindow.xaml` CanvasGrid) + `BrandFlashTimer` in `MainViewModel` — cadence 300s, first flash
~5s after go-live, only while live or recording. An always-on watermark can be cropped or covered;
an intermittent full-frame flash can't be cropped and is impractical to edit around on a live feed.
- **Paid (one-time):** branding flash removed (flips `BrandFlashEnabled` off) + **Alerts**
(Super Chat / membership / subscribe pop-ins).
Deliberately rejected: always-on watermark (obscurable — replaced by the flash), 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).