# SuiteLink Client

Cross-platform `.NET 10` C# client for AVEVA SuiteLink tag operations.

## Scope

Current implementation targets the normal SuiteLink tag protocol and supports:

- startup handshake and connect message encoding
- subscribe and unadvise flows
- update decoding for `bool`, `int32`, `float32`, and `string`
- write (`POKE`) encoding for `bool`, `int32`, `float32`, and `string`
- background receive loop for subscription updates without manual polling
- automatic reconnect with durable subscription replay after runtime disconnects
- best-effort latest-value catch-up replay after reconnect when enabled
- policy-based reconnect retry timing with exponential backoff and jitter support
- client/session/transport layers suitable for macOS, Linux, and Windows

## Unsupported

This repository does not currently support:

- AlarmMgr / alarms and events
- secure SuiteLink V3 / TLS transport
- write queuing while reconnecting
- full outage-history replay of every missed value
- validated reconnect behavior against a live AVEVA server deployment
- validated support for richer System Platform data types such as `double`, `int64`, or `DateTime`

## Build

```bash
dotnet build /Users/dohertj2/Desktop/suitelinkclient/SuiteLink.Client.slnx -c Release
```

## Test

Unit tests:

```bash
dotnet test /Users/dohertj2/Desktop/suitelinkclient/SuiteLink.Client.slnx -v minimal
```

Focused protocol tests:

```bash
dotnet test /Users/dohertj2/Desktop/suitelinkclient/SuiteLink.Client.slnx --filter Protocol -v minimal
```

## Integration

Live integration tests are safe by default and only run when explicitly enabled with environment variables.

See [README.md](/Users/dohertj2/Desktop/suitelinkclient/tests/SuiteLink.Client.IntegrationTests/README.md) for:

- required environment variables
- tag configuration
- enabling live round-trip tests for `bool`, `int`, `float`, and `string`

## Notes

- The repository includes fixture-backed protocol tests under [Fixtures](/Users/dohertj2/Desktop/suitelinkclient/tests/SuiteLink.Client.Tests/Fixtures).
- Protocol assumptions derived from reverse engineering are intentionally isolated in codec classes and tests so they can be refined against live captures later.
- Normal subscription use does not require calling `ProcessIncomingAsync`; the runtime loop dispatches updates in the background.
- After a runtime disconnect, the client enters `Reconnecting`, rebuilds the transport/session startup sequence, replays durable subscriptions, and resumes dispatch without caller resubscription.
- Reconnect timing is driven by `SuiteLinkRetryPolicy`; the default policy retries immediately, then uses bounded exponential backoff with jitter.
- Catch-up replay is best-effort latest-value refresh only. It does not represent every value missed during the outage window.
- If the client is reconnecting after a runtime disconnect, `WriteAsync` fails fast until the session is ready again.
- Reconnect behavior is currently verified with fixture-backed and fake-transport tests; live AVEVA validation is still required, especially for mixed-mode deployments and server-specific timing.