# Changelog

## 0.2.0

Precedence between strategies is now a first-class object instead of an if/else
ladder, ahead of there being more than three of them.

Every strategy returns a CLAIM each cycle - `set` ("I want X") or `limit` ("the
result must stay within these bounds") - and `arbiter.py` resolves them by one
rule:

  1. Highest-priority `set` wins; no claim at all means 0 W.
  2. Then every `limit` whose priority is >= that set's priority applies, most
     restrictive first.
  3. Contradictory limits are a BUG: command 0 W and say so.

Clause 2 is why "money outranks maintenance" is now a consequence of the
priorities rather than a special case in a Jinja template: the maintenance
charge-only limit binds the loop, but will not bind a higher-priority peak
shaving claim when one exists.

- Maintenance shaping (charge-only, cheap-window floor) moved out of the control
  law. `control.py` is once again only a controller that tracks the meter.
- The loop computes from the ARBITER's last output, not its own last wish. If
  something outranked it, that is what the hardware actually did, and tracking
  anything else makes it jump when it regains control.
- Every decision is explainable: "loop -> 0 W, limited by maintenance
  (charge-only)" now appears in the UI and the log, instead of a bare number.
- Safety limits (device rating, supervised max_w) bind every strategy including
  the highest, and are still enforced a second time at the point of writing.

## 0.1.6

Findings from installing this on a live system, replacing a working YAML
implementation. Every one of these was silent - the add-on looked healthy while
being completely unable to do its job.

- **`run.sh` must use `#!/usr/bin/with-contenv sh`.** The HA base images run
  s6-overlay, which starts services with a SANITISED environment. With a plain
  shebang, SUPERVISOR_TOKEN is simply absent and every Home Assistant call
  returns 401 - while `homeassistant_api: true` makes the permissions look
  correctly granted. Startup now logs the token length and probes the Core API,
  so the next person sees it in one line.
- **Bump `version:` for every change.** Supervisor keys the built image by
  version, so editing source and rebuilding silently reuses the old image. Two
  fixes appeared not to work because of this.
- **Dependencies come from apk, not pip.** Alpine is musl and there are no musl
  wheels for aiohttp; pip would compile it on the client's Pi.
- **paho-mqtt 1.x and 2.x are both supported.** Alpine ships 1.x, which has no
  `CallbackAPIVersion`; that raised and took the whole add-on down with it.
- **MQTT can no longer take down control.** Publisher construction is wrapped -
  observability must never stop the controller.
- **MQTT discovery is published from `on_connect`.** paho drops QoS-0 publishes
  issued before the CONNACK, so announcing straight after `connect()` published
  nothing at all while logging "MQTT connected".
- **Repeated failures log at most once a minute.** The control loop retries every
  second; unthrottled warnings rolled the log buffer and destroyed the startup
  diagnostics needed to debug the 401 above.
- **`auto_start` works.** The store's defaults supplied `auto: False`, so the
  fallback to the option could never fire.

Known issue: after deleting the MQTT entities from the registry during
development, Home Assistant would not re-adopt them from retained discovery -
not even after clearing the retained topics and reconnecting. The add-on
publishes correct discovery and live state (verified on the broker); this is an
HA-side adoption problem and affects status entities only, never control.

## 0.1.0

First packaged release. Ports the control loop and the monthly maintenance
cycle from the reference Home Assistant implementation into an add-on.

- Grid-following control: gain/slew/clamp/deadband with anti-windup, all tuned
  against measured hardware behaviour (see FIELD-GUIDE.md §14).
- Saturation freeze **with the duration term** — three consecutive diverging
  cycles, not one. The instantaneous test fires on every large correction,
  because the plant itself needs 3-6 s to settle.
- Monthly maintenance cycle as an ownership state machine: drain / charge /
  hold, with exactly one writer of the setpoint at any moment.
- Capacity-tariff awareness: the maintenance charge is capped by quarter-hour
  peak headroom, and peak shaving outranks the maintenance schedule.
- Failsafe behaviour: commands 0 W on missing inputs, on stop, and on shutdown.
  Never replays a stale setpoint - the reference implementation did, and the
  hardware watchdog cannot catch that.
- Ingress UI with a commissioning checklist that names problems in words.
- Optional MQTT discovery for status entities.

Known limits:

- Home Assistant OS / Supervised only (add-ons cannot run on Container/Core).
- The inverter protocol is reverse-engineered; no vendor contract.
- Without the optional RS485 e-stop, nothing covers the host machine dying.