# PeerSpeak Codebase Layout and Architecture Rules

When working in the PeerSpeak repository, adhere to the following architectural boundaries and layout:

## Code Layout
- `src/main.rs`: The application entry point (initializes Tokio and the Iced GUI).
- `src/app/`: The UI layer (Iced). Handles themes, views (Home, Room, Settings), and visual state. Must communicate with the core via message passing (`UiEvent`/`CoreCommand`), not direct function calls.
- `src/core/`: The central orchestrator. 
  - `mod.rs`: Manages the session lifecycle, ties together network and UI, and manages the async mixer tasks.
  - `jitter.rs`: Houses the adaptive playout delay JitterBuffer and Packet Loss Concealment (PLC) logic.
- `src/network/`: The "Dual-Plane" transport layer.
  - `gossip.rs` (Control Plane): Built on `iroh-gossip`. Manages room rosters, verified membership, presence, and chat via cryptographically signed envelopes.
  - `iroh_impl.rs` (Data Plane): Manages raw QUIC endpoints and peer connections. Forwards UDP voice datagrams directly to peers for minimum latency.
- `src/audio/`: Hardware audio backends.
  - Interfaces heavily with `cpal_impl.rs` (Windows/WASAPI) and `pipewire_impl.rs` (Linux). 
  - **CRITICAL RULE**: The RT audio callbacks are strictly lock-free. They communicate with the async core exclusively via Single-Producer Single-Consumer (SPSC) ring buffers (`HeapRb`). Never allocate memory, log to stdout, or lock Mutexes on the RT threads.
- `src/codec/`: Audio compression abstractions, standardizing on Opus at 48kHz mono (`opus_impl.rs`).

## General Directives
- **Security**: Audio admission is strictly derived from the verified gossip roster (S8). Never trust raw UDP sender IDs without validating against gossip.
- **Latency**: Preserve the deterministic dialer vs acceptor logic in the QUIC layer to prevent connection loops.