# uopi

A web-based HMI (Human-Machine Interface) for monitoring and controlling EPICS-based scientific and industrial control systems.

uopi runs as a single portable binary. Access it from any browser — including over an SSH tunnel — with no client-side installation required.

---

## Features

- **Live data** from EPICS (Channel Access / PVAccess) and user-defined synthetic signals
- **Web-based HMI editor** — drag-and-drop widgets, resize, align, undo/redo — saved as XML
- **Rich widget library** — gauges, LEDs, bars, plots (time series, FFT, waterfall, histogram), controls
- **Multiple concurrent clients** sharing the same data subscriptions
- **Historical data** navigation via EPICS Archive Appliance integration
- **Synthetic signals** — compose, filter, and transform existing signals with a DSP pipeline or Lua scripts
- **Single binary** with embedded frontend; no runtime dependencies

---

## Quick Start

### Prerequisites

- EPICS Base installed (for the EPICS data source; `libca` must be linkable)
- Go 1.22+
- Node.js 20+ and npm

### Build

```bash
make all
```

The binary is written to `dist/uopi`.

### Run

```bash
./dist/uopi --config uopi.toml
```

Then open `http://localhost:8080` in your browser.

**SSH tunnel example:**

```bash
ssh -L 8080:localhost:8080 user@controlhost
# then open http://localhost:8080 locally
```

---

## Configuration

Create `uopi.toml` (or copy and edit the example):

```toml
[server]
listen    = ":8080"
storage_dir = "./interfaces"   # where interface XML files are stored

[datasource.epics]
enabled      = true
ca_addr_list = ""              # overrides EPICS_CA_ADDR_LIST if non-empty
archive_url  = ""              # EPICS Archive Appliance base URL

[datasource.synthetic]
enabled          = true
definitions_file = "./synthetic.json"
```

All settings can be overridden with environment variables using the prefix `UOPI_` and double underscores for nesting, e.g. `UOPI_SERVER_LISTEN=":9090"`.

---

## Development

See [`docs/TECHNICAL_SPEC.md`](docs/TECHNICAL_SPEC.md) for full architecture details.

```bash
# Backend only (with stub data source)
go run ./cmd/uopi

# Frontend dev server (proxies /api to backend at :8080)
cd web && npm install && npm run dev

# Run backend tests
go test ./...

# Run a single backend test
go test ./internal/broker/... -run TestFanOut

# Frontend type-check
cd web && npm run check

# Frontend lint
cd web && npm run lint

# Full build (frontend + backend)
make all

# Run all tests
make test
```

---

## Docs

| Document | Description |
|----------|-------------|
| [`docs/FUNCTIONAL_SPEC.md`](docs/FUNCTIONAL_SPEC.md) | User-facing feature specification |
| [`docs/TECHNICAL_SPEC.md`](docs/TECHNICAL_SPEC.md) | Technology choices, architecture, API design |
| [`docs/WORK_PLAN.md`](docs/WORK_PLAN.md) | Phased development plan with milestones |

---

## License

TBD