# continuum-proxy

Edge gateway daemon for the Continuum print farm platform. Runs on a Linux SBC
on-site, discovers and talks to printers over the LAN, and maintains a
resilient uplink to the cloud control plane (`continuum-backend`).

## Responsibilities

- **Uplink** (`src/uplink/`): persistent WebSocket connection to
  `wss://api.domain.com/ws/edge/v1` with exponential-backoff reconnects,
  heartbeat ping/pong, and inbound task dispatch.
- **Printer adapters** (`src/adapters/`): protocol clients per printer vendor —
  Bambu Lab (MQTT 8883 + FTPS 990), PrusaLink (REST), Klipper (Moonraker WS).
- **Plate changer** (`src/plate_changer/`): mechanical cycle execution and
  sensor validation over GPIO/serial for automated plate-swap hardware.
- **Local cache** (`rusqlite`): buffers telemetry and job state through
  connectivity gaps so nothing is lost if the uplink drops.
- **go2rtc watchdog**: supervises the bundled `go2rtc` process for camera
  restreaming (RTSP/USB → WebRTC).

## Getting started

```bash
cp .env.example .env
cargo run
```

## Structure

```
src/
  main.rs            Multi-threaded async engine: uplink, discovery, go2rtc watchdog
  uplink/             Cloud WebSocket client (reconnect, heartbeat, dispatch)
  adapters/           bambu.rs, prusalink.rs, moonraker.rs — wire-protocol clients
  printer/            Domain model: Printer trait + PrinterBase + PrinterHandle enum
  plate_changer/      Mechanical cycle control + sensor validation
  discovery/          LAN printer discovery (SSDP / mDNS / static config)
```

`src/adapters/` talks the raw wire protocols (MQTT, FTPS, HTTP, WS).
`src/printer/` is the vendor-agnostic domain model layered on top: a
`Printer` trait plus one struct per vendor (`BambuPrinter`, `PrusaPrinter`,
`KlipperPrinter`) wrapped in a closed `PrinterHandle` enum. Rust has no class
inheritance, so this trait+enum combo is what stands in for a
`GenericPrinter -> BambuPrinter` hierarchy — composition for shared fields,
a trait for shared/overridable behavior, an enum for the closed set of
vendors. See `examples/printer_polymorphism.rs`:

```bash
cargo run --example printer_polymorphism
```