add capability to restrict remote panel modes

Improve MK2 frames handling

.drone.yml

@@ -0,0 +1,202 @@
+kind: pipeline
+type: docker
+name: ci
+
+trigger:
+  event:
+    - pull_request
+    - push
+    - tag
+
+steps:
+  # - name: lint
+  #   image: cache.coadcorp.com/library/golang:1.26
+  #   environment:
+  #     GOFLAGS: -mod=mod
+  #     GOBIN: /usr/local/bin
+  #   commands:
+  #     - go install github.com/golangci/golangci-lint/cmd/golangci-lint@v1.64.8
+  #     - golangci-lint version
+  #     - golangci-lint run --timeout=5m
+
+  # - name: test
+  #   image: cache.coadcorp.com/library/golang:1.26
+  #   environment:
+  #     GOFLAGS: -mod=mod
+  #   commands:
+  #     - go test -v -race -coverprofile=coverage.txt -covermode=atomic ./...
+
+  - name: build
+    image: cache.coadcorp.com/library/golang:1.26
+    environment:
+      GOFLAGS: -mod=mod
+    commands:
+      - CGO_ENABLED=0 go build -v ./cmd/invertergui
+
+  - name: build-linux-binaries
+    image: cache.coadcorp.com/library/golang:1.26
+    environment:
+      GOFLAGS: -mod=mod
+    commands:
+      - mkdir -p dist
+      - CGO_ENABLED=0 GOOS=linux GOARCH=amd64 go build -v -o dist/invertergui-linux-amd64 ./cmd/invertergui
+      - CGO_ENABLED=0 GOOS=linux GOARCH=arm64 go build -v -o dist/invertergui-linux-arm64 ./cmd/invertergui
+    when:
+      event:
+        - push
+        - tag
+
+  - name: docker-build-validate
+    image: gcr.io/kaniko-project/executor:v1.24.0
+    commands:
+      - /kaniko/executor --context "${DRONE_WORKSPACE}" --dockerfile "${DRONE_WORKSPACE}/Dockerfile" --no-push --destination registry.coadcorp.com/nathan/invertergui:pr-${DRONE_BUILD_NUMBER}
+    when:
+      event:
+        - pull_request
+
+  - name: docker-publish-commit-amd64
+    image: plugins/docker
+    settings:
+      registry: registry.coadcorp.com
+      repo: "registry.coadcorp.com/nathan/invertergui"
+      dockerfile: Dockerfile.publish.amd64
+      username: nathan
+      password:
+        from_secret: registry_password
+      tags:
+        - "${DRONE_COMMIT_SHA}-linux-amd64"
+    when:
+      event:
+        - push
+
+  - name: docker-publish-commit-arm64
+    image: plugins/docker
+    settings:
+      registry: registry.coadcorp.com
+      repo: "registry.coadcorp.com/nathan/invertergui"
+      dockerfile: Dockerfile.publish.arm64
+      username: nathan
+      password:
+        from_secret: registry_password
+      tags:
+        - "${DRONE_COMMIT_SHA}-linux-arm64"
+    when:
+      event:
+        - push
+
+  - name: docker-manifest-commit
+    image: plugins/manifest
+    settings:
+      registry: registry.coadcorp.com
+      username: nathan
+      password:
+        from_secret: registry_password
+      target: "registry.coadcorp.com/nathan/invertergui:${DRONE_COMMIT_SHA}"
+      template: "registry.coadcorp.com/nathan/invertergui:${DRONE_COMMIT_SHA}-OS-ARCH"
+      platforms:
+        - "linux/amd64"
+        - "linux/arm64"
+    when:
+      event:
+        - push
+
+  - name: docker-publish-latest-amd64
+    image: plugins/docker
+    settings:
+      registry: registry.coadcorp.com
+      repo: "registry.coadcorp.com/nathan/invertergui"
+      dockerfile: Dockerfile.publish.amd64
+      username: nathan
+      password:
+        from_secret: registry_password
+      tags:
+        - "latest-linux-amd64"
+    when:
+      event:
+        - push
+      branch:
+        - main
+        - master
+
+  - name: docker-publish-latest-arm64
+    image: plugins/docker
+    settings:
+      registry: registry.coadcorp.com
+      repo: "registry.coadcorp.com/nathan/invertergui"
+      dockerfile: Dockerfile.publish.arm64
+      username: nathan
+      password:
+        from_secret: registry_password
+      tags:
+        - "latest-linux-arm64"
+    when:
+      event:
+        - push
+      branch:
+        - main
+        - master
+
+  - name: docker-manifest-latest
+    image: plugins/manifest
+    settings:
+      registry: registry.coadcorp.com
+      username: nathan
+      password:
+        from_secret: registry_password
+      target: "registry.coadcorp.com/nathan/invertergui:latest"
+      template: "registry.coadcorp.com/nathan/invertergui:latest-OS-ARCH"
+      platforms:
+        - "linux/amd64"
+        - "linux/arm64"
+    when:
+      event:
+        - push
+      branch:
+        - main
+        - master
+
+  - name: docker-publish-release-amd64
+    image: plugins/docker
+    settings:
+      registry: registry.coadcorp.com
+      repo: "registry.coadcorp.com/nathan/invertergui"
+      dockerfile: Dockerfile.publish.amd64
+      username: nathan
+      password:
+        from_secret: registry_password
+      tags:
+        - "${DRONE_TAG}-linux-amd64"
+    when:
+      event:
+        - tag
+
+  - name: docker-publish-release-arm64
+    image: plugins/docker
+    settings:
+      registry: registry.coadcorp.com
+      repo: "registry.coadcorp.com/nathan/invertergui"
+      dockerfile: Dockerfile.publish.arm64
+      username: nathan
+      password:
+        from_secret: registry_password
+      tags:
+        - "${DRONE_TAG}-linux-arm64"
+    when:
+      event:
+        - tag
+
+  - name: docker-manifest-release
+    image: plugins/manifest
+    settings:
+      registry: registry.coadcorp.com
+      username: nathan
+      password:
+        from_secret: registry_password
+      target: "registry.coadcorp.com/nathan/invertergui:${DRONE_TAG}"
+      template: "registry.coadcorp.com/nathan/invertergui:${DRONE_TAG}-OS-ARCH"
+      platforms:
+        - "linux/amd64"
+        - "linux/arm64"
+    when:
+      event:
+        - tag

.gitignore

@@ -22,3 +22,9 @@ _testmain.go
 *.exe
 *.test
 *.prof
+
+vendor/
+
+# Python cache files (for Home Assistant custom component)
+__pycache__/
+*.pyc

.golangci.yml

@@ -1,29 +0,0 @@
-run:
-  deadline: 10m
-
-linters:
-  enable-all: false
-  enable:
-    # Enabled by default in golangci-lint v1.13.2
-    - deadcode
-    - errcheck
-    - govet
-    - ineffassign
-    - typecheck
-    - varcheck
-    # Disabled by default in golangci-lint v1.13.2
-    - dupl
-    - goconst
-    - gofmt
-    - golint
-    - unconvert
-    # The following result in high memory usage (>1GB)
-    # https://github.com/golangci/golangci-lint/issues/337
-    - staticcheck
-    - structcheck
-    - gosimple
-    - unused
-
-issues:
-  max-per-linter: 0
-  max-same-issues: 0

.travis.yml

@@ -1,28 +0,0 @@
-sudo: false
-
-language: go
-
-env:
-  - GO111MODULE=on
-
-go:
-  - 1.12.x
-
-git:
-  depth: 1
-
-install: true
-
-notifications:
-  email: false
-
-before_script:
-  - curl -sfL https://install.goreleaser.com/github.com/golangci/golangci-lint.sh | sh -s -- -b $(go env GOPATH)/bin v1.15.0
-  - go mod vendor
-
-script:
-  - golangci-lint run
-  - go test -v -race  -coverprofile=coverage.txt -covermode=atomic ./...
-
-after_success:
-  - bash <(curl -s https://codecov.io/bash)

.vscode/settings.json

@@ -10,5 +10,13 @@
   "[go]": {
     "editor.insertSpaces": false,
     "editor.tabSize": 4
-  }
+  },
+  "cSpell.words": [
+    "diebietse",
+    "ghaction",
+    "ghcr",
+    "golangci",
+    "invertergui",
+    "semver"
+  ]
 }

Dockerfile

@@ -1,14 +1,24 @@
-FROM golang:alpine as builder
-RUN apk add git
+ARG BUILDPLATFORM=linux/amd64
+FROM --platform=${BUILDPLATFORM} golang:1.26-alpine as builder
+
+ARG TARGETOS=linux
+ARG TARGETARCH=amd64
+ARG TARGETVARIANT
+
 RUN mkdir /build
 COPY . /build/
 WORKDIR /build
-RUN go build -o invertergui ./cmd/invertergui
-FROM alpine
-RUN adduser -S -D -H -h /app inverteruser
-RUN addgroup inverteruser dialout
-USER inverteruser
-COPY --from=builder /build/invertergui /app/
-WORKDIR /app
-ENTRYPOINT [ "./invertergui" ]
-CMD []
+RUN set -eux; \
+    GOARM=""; \
+    if [ "${TARGETARCH}" = "arm" ] && [ -n "${TARGETVARIANT:-}" ]; then GOARM="${TARGETVARIANT#v}"; fi; \
+    CGO_ENABLED=0 GOOS="${TARGETOS}" GOARCH="${TARGETARCH}" GOARM="${GOARM}" go build -o invertergui ./cmd/invertergui
+
+FROM scratch
+
+# Group ID 20 is dialout, needed for tty read/write access
+USER 3000:20
+ENV READ_ONLY=false
+ENV CONTROL_ALLOWED_PANEL_MODES=""
+COPY --from=builder /build/invertergui /bin/
+ENTRYPOINT [ "/bin/invertergui" ]
+EXPOSE 8080

Dockerfile.publish.amd64

@@ -0,0 +1,9 @@
+FROM scratch
+
+# Group ID 20 is dialout, needed for tty read/write access
+USER 3000:20
+ENV READ_ONLY=false
+ENV CONTROL_ALLOWED_PANEL_MODES=""
+COPY dist/invertergui-linux-amd64 /bin/invertergui
+ENTRYPOINT ["/bin/invertergui"]
+EXPOSE 8080

Dockerfile.publish.arm64

@@ -0,0 +1,9 @@
+FROM scratch
+
+# Group ID 20 is dialout, needed for tty read/write access
+USER 3000:20
+ENV READ_ONLY=false
+ENV CONTROL_ALLOWED_PANEL_MODES=""
+COPY dist/invertergui-linux-arm64 /bin/invertergui
+ENTRYPOINT ["/bin/invertergui"]
+EXPOSE 8080

Makefile

@@ -26,7 +26,7 @@
 #OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 #OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-.PHONY: test test-race vet install gofmt docker statik lint clean invertergui
+.PHONY: test test-race vet install gofmt docker statik lint clean invertergui vendor
 
 .DEFAULT_GOAL = invertergui
 
@@ -39,19 +39,24 @@ gofmt:
 	gofmt -l -s -w .
 
 test:
-	go test -v ./...
-
-test-race:
 	go test -v -race ./...
 
 docker:
 	docker build --tag invertergui .
 
-statik:
-	statik -f -p=frontend -src=./frontend/root
-
 lint:
-	golangci-lint run
+	docker run --rm -it \
+		-w /src -v $(shell pwd):/src \
+		golangci/golangci-lint:v1.56 golangci-lint run \
+		-v -c .golangci.yml
 
 clean:
 	rm ./invertergui
+
+vendor:
+	go mod tidy
+	go mod vendor
+
+.PHONY: upgrade-vendor
+upgrade-vendor:
+	go get -u ./...

README.md

@@ -1,39 +1,195 @@
 # Inverter GUI
 
-[![Build Status](https://travis-ci.org/diebietse/invertergui.svg?branch=master)](https://travis-ci.org/diebietse/invertergui)
+[Repository](https://git.coadcorp.com/nathan/invertergui) | [Container Image](https://registry.coadcorp.com/nathan/invertergui)
 
 The invertergui allows the monitoring of a [Victron Multiplus](https://www.victronenergy.com/inverters-chargers/multiplus-12v-24v-48v-800va-3kva) via the [MK3/MK2 USB](https://www.victronenergy.com/accessories/interface-mk3-usb) or the MK2 RS232.
 
-The [`diebietse/invertergui`](https://hub.docker.com/r/diebietse/invertergui) docker image is a build of this repository.
+The [`registry.coadcorp.com/nathan/invertergui`](https://registry.coadcorp.com/nathan/invertergui) container image is a build of this repository.
+
+The code has been updated to support more of the protocol published by Victron at https://www.victronenergy.com/upload/documents/Technical-Information-Interfacing-with-VE-Bus-products-MK2-Protocol-3-14.pdf 
+
+## Acknowledgements
+
+This project is based on the original open source `invertergui` project by Hendrik van Wyk and contributors:
+
+- Original repository: https://github.com/diebietse/invertergui
+- Home Assistant `victron-mk3-hass` inspiration: https://github.com/j9brown/victron-mk3-hass
 
 ## Demo
 
-![demo](https://rawcdn.githack.com/diebietse/invertergui/c856c451cd5c926b588914583bc4ab1498b7da99/invertergui_demo.gif "Invertergui Demo")
+![demo](./invertergui_demo.gif "Invertergui Demo")
 
 ## Quick Start
 
 ```console
-docker run --name invertergui --device /dev/ttyUSB0:/dev/ttyUSB0 -p 8080:8080 diebietse/invertergui
+docker run --name invertergui --device /dev/ttyUSB0:/dev/ttyUSB0 -p 8080:8080 registry.coadcorp.com/nathan/invertergui:latest
 ```
 
 ## Requirements
 
-This project makes use of [Go Modules](https://github.com/golang/go/wiki/Modules). The minimum version for Go is 1.11.x.
+This project makes use of [Go Modules](https://github.com/golang/go/wiki/Modules). The minimum supported version for Go is 1.22
+
+## Driver API: Metadata + Safe Transactions
+
+The MK2 driver now includes a metadata and transaction safety layer via the
+`mk2driver.MetadataControl` interface:
+
+- Register metadata lookup (`RegisterMetadata`, `ListRegisterMetadata`)
+- Generic register reads by kind/id (`ReadRegister`)
+- Transactional writes with retry and verify (`WriteRegister`)
+
+`WriteRegister` supports:
+
+- `ReadBeforeWrite`
+- `VerifyAfterWrite`
+- configurable retry count and delay
+
+This layer is additive and does not replace existing `WriteSetting`, `WriteRAMVar`,
+or panel control APIs.
+
+## Advanced Control + Orchestration Features
+
+The codebase now includes:
+
+- Full MK2 command-path coverage in driver APIs for:
+  - `0x0E` device state read/write
+  - register read by id (`0x30`, `0x31`)
+  - selected read/write flows (`0x32`, `0x33`, `0x34`, `0x35`)
+  - RAM var metadata/info (`0x36`)
+  - write-by-id flows (`0x37`, `0x38`)
+- Register metadata with `unit`, `min/max`, `scale`, `writable`, and `safety_class`.
+- Transaction-safe writes with read-before-write, verify-after-write, retry/backoff, and timeout classes.
+- Snapshot/diff/restore register workflows with rollback on partial restore failure.
+- Alarm engine with LED/state alarms + command-failure alarms, including debounce and clear behavior.
+- Venus-like derived operating state model: `Off`, `Inverter`, `Charger`, `Passthru`, `Fault`.
+- Historical counters for energy and availability:
+  - `energy_in_wh`, `energy_out_wh`
+  - battery charge/discharge Wh
+  - uptime seconds
+  - fault count + last fault timestamp
+- Multi-device orchestration fields and topics:
+  - `device_id`, `instance_id`, `phase`, `phase_group`
+  - per-device topics and phase-group fanout topics
+- Command arbitration/policy layer:
+  - single serialized write path
+  - lockout windows
+  - source tagging (`ui`, `mqtt`, `automation`)
+  - max current guardrail + mode rate limit + maintenance/read-only profiles
+- Venus-compatible MQTT mode (`N/...` + optional `W/...`) for HA/Node-RED/VRM-style workflows.
+- Guide-style Victron ESS MQTT paths (`settings/0/Settings/CGwacs/*`) with `victron/N/...` and `victron/W/...` prefix compatibility.
+- Structured diagnostics bundle topics with protocol traces, recent command history, and health score.
 
 ## Getting started
 
 ```bash
- Usage of ./invertergui:
-  -addr string
-    	TCP address to listen on. (default ":8080")
-  -dev string
-    	TTY device to use. (default "/dev/ttyUSB0")
-  -ip string
-    	IP to connect when using tcp connection. (default "localhost:8139")
-  -tcp
-    	Use TCP instead of TTY
+Usage:
+  invertergui [OPTIONS]
+
+Application Options:
+      --address=        The IP/DNS and port of the machine that the application is running on. (default: :8080) [$ADDRESS]
+      --read_only       Disable all write operations and run in monitoring-only mode. [$READ_ONLY]
+      --data.source=    Set the source of data for the inverter gui. "serial", "tcp" or "mock" (default: serial) [$DATA_SOURCE]
+      --data.host=      Host to connect when source is set to tcp. (default: localhost:8139) [$DATA_HOST]
+      --data.device=    TTY device to use when source is set to serial. (default: /dev/ttyUSB0) [$DATA_DEVICE]
+      --cli.enabled     Enable CLI output. [$CLI_ENABLED]
+      --mqtt.enabled    Enable MQTT publishing. [$MQTT_ENABLED]
+      --mqtt.broker=    Set the host port and scheme of the MQTT broker. (default: tcp://localhost:1883) [$MQTT_BROKER]
+      --mqtt.client_id= Set the client ID for the MQTT connection. (default: inverter-gui) [$MQTT_CLIENT_ID]
+      --mqtt.topic=     Set the MQTT topic updates published to. (default: invertergui/updates) [$MQTT_TOPIC]
+      --mqtt.command_topic= Set the MQTT topic that receives write commands for Victron settings/RAM variables. (default: invertergui/settings/set) [$MQTT_COMMAND_TOPIC]
+      --mqtt.status_topic=  Set the MQTT topic where write command status updates are published. (default: invertergui/settings/status) [$MQTT_STATUS_TOPIC]
+      --mqtt.device_id= Set logical device ID used for per-device orchestration topics. (default: invertergui) [$MQTT_DEVICE_ID]
+      --mqtt.history_size= Number of samples retained for rolling history summaries. (default: 120) [$MQTT_HISTORY_SIZE]
+      --mqtt.instance_id= Device instance ID for multi-device orchestration and Venus compatibility. (default: 0) [$MQTT_INSTANCE_ID]
+      --mqtt.phase=    Electrical phase label for this instance (L1/L2/L3). (default: L1) [$MQTT_PHASE]
+      --mqtt.phase_group= Grouping key for parallel/3-phase system aggregation topics. (default: default) [$MQTT_PHASE_GROUP]
+      --mqtt.ha.enabled Enable Home Assistant MQTT discovery integration. [$MQTT_HA_ENABLED]
+      --mqtt.ha.discovery_prefix= Set Home Assistant MQTT discovery prefix. (default: homeassistant) [$MQTT_HA_DISCOVERY_PREFIX]
+      --mqtt.ha.node_id= Set Home Assistant node ID used for discovery topics and unique IDs. (default: invertergui) [$MQTT_HA_NODE_ID]
+      --mqtt.ha.device_name= Set Home Assistant device display name. (default: Victron Inverter) [$MQTT_HA_DEVICE_NAME]
+      --mqtt.venus.enabled Enable Venus-style MQTT compatibility topics (N/W model). [$MQTT_VENUS_ENABLED]
+      --mqtt.venus.portal_id= Set Venus portal ID segment used in N/W topics. (default: invertergui) [$MQTT_VENUS_PORTAL_ID]
+      --mqtt.venus.service= Set Venus service segment used in N/W topics. (default: vebus/257) [$MQTT_VENUS_SERVICE]
+      --mqtt.venus.subscribe_writes Subscribe to Venus W/... topics and map to MK2 commands. [$MQTT_VENUS_SUBSCRIBE_WRITES]
+      --mqtt.venus.topic_prefix= Optional topic prefix before Venus N/W topics, e.g. victron. [$MQTT_VENUS_TOPIC_PREFIX]
+      --mqtt.venus.guide_compat Enable guide-style settings/0/Settings/CGwacs compatibility paths. [$MQTT_VENUS_GUIDE_COMPAT]
+      --mqtt.username=  Set the MQTT username [$MQTT_USERNAME]
+      --mqtt.password=  Set the MQTT password [$MQTT_PASSWORD]
+      --mqtt.password-file= Path to a file containing the MQTT password [$MQTT_PASSWORD_FILE]
+      --control.profile= Write policy profile: normal, maintenance, or read_only. (default: normal) [$CONTROL_PROFILE]
+      --control.max_current_limit= Optional max AC current limit guardrail in amps (0 disables). (default: 0) [$CONTROL_MAX_CURRENT_LIMIT]
+      --control.mode_change_min_interval= Minimum time between mode changes. (default: 3s) [$CONTROL_MODE_CHANGE_MIN_INTERVAL]
+      --control.lockout_window= Post-command lockout window for command arbitration. (default: 0s) [$CONTROL_LOCKOUT_WINDOW]
+      --control.allowed_panel_modes= Comma-separated allowlist of remote panel modes. Supported values: on, off, charger_only, inverter_only. Empty allows all modes. [$CONTROL_ALLOWED_PANEL_MODES]
+      --loglevel=       The log level to generate logs at. ("panic", "fatal", "error", "warn", "info", "debug", "trace") (default: info) [$LOGLEVEL]
+
+Help Options:
+  -h, --help            Show this help message
 ```
 
+### Read-Only Mode
+
+Set `READ_ONLY=true` (or `--read_only`) to disable all write operations.
+When read-only mode is enabled, the app still monitors and publishes telemetry, but it will not send commands to the Victron device.
+
+This affects:
+
+- MQTT command handling (`--mqtt.command_topic` commands are ignored)
+- Web UI control actions (`POST /api/remote-panel/state` and `POST /api/remote-panel/standby`)
+
+### Remote Panel Mode Allowlist
+
+Set `CONTROL_ALLOWED_PANEL_MODES` (or `--control.allowed_panel_modes`) to restrict which
+remote panel modes can be selected from Web UI, MQTT, Home Assistant, and Venus-compatible
+write paths.
+
+Supported values:
+
+- `on`
+- `off`
+- `charger_only`
+- `inverter_only`
+
+Use a comma-separated list. Empty means all modes are allowed.
+
+Example:
+
+- `CONTROL_ALLOWED_PANEL_MODES=off,charger_only`
+
+Example `docker-compose.yml` snippet:
+
+```yaml
+services:
+  invertergui:
+    image: registry.coadcorp.com/nathan/invertergui:latest
+    environment:
+      READ_ONLY: "true"
+      CONTROL_ALLOWED_PANEL_MODES: "off,charger_only"
+    devices:
+      - "/dev/ttyUSB0:/dev/ttyUSB0"
+    command: ["--mqtt.enabled", "--mqtt.broker=tcp://192.168.1.1:1883", "--loglevel=info"]      
+```
+
+### Home Assistant Guide-Style ESS Control
+
+To mimic the Victron community ESS control approach (MQTT `N/...` state + `W/...` writes under `settings/0/Settings/CGwacs/...`):
+
+1. Start invertergui with:
+   - `MQTT_VENUS_ENABLED=true`
+   - `MQTT_VENUS_GUIDE_COMPAT=true`
+   - `MQTT_VENUS_TOPIC_PREFIX=victron`
+   - `MQTT_VENUS_PORTAL_ID=invertergui` (or your chosen portal id)
+2. In Home Assistant:
+   - Use the included custom integration (`custom_components/victron_mk2_mqtt`) which now exposes ESS-style entities and service calls.
+   - Or use `homeassistant/packages/invertergui_mqtt.yaml`, which includes guide-style MQTT entities:
+     - `number.victron_ess_grid_setpoint`
+     - `number.victron_ess_max_charge_power`
+     - `number.victron_ess_max_discharge_power`
+     - `switch.victron_ess_optimized_mode`
+
+Compatibility note:
+- MK2/VE.Bus does not expose every Venus ESS feature one-to-one. This project maps ESS-style commands onto available MK2 controls (mode/current-limit/policy-safe behavior) to provide similar Home Assistant control flow.
+
 ## Port 8080
 
 The default HTTP server port is hosted on port 8080. This exposes the HTTP server that hosts the:
@@ -69,6 +225,20 @@ Battery Power: -0.659 W
 Battery Charge: 100.000 %
 ```
 
+The web UI also includes a **Remote Panel Control** section for:
+
+- Remote Panel Mode (`on`, `off`, `charger_only`, `inverter_only`)
+- Remote Panel Current Limit (AC input current limit in amps)
+- Remote Panel Standby (prevent sleep while turned off)
+
+The combined mode + current limit action maps to the same behavior as
+`set_remote_panel_state` in `victron-mk3`.
+
+The backing HTTP API endpoints are:
+
+- `GET/POST /api/remote-panel/state`
+- `GET/POST /api/remote-panel/standby`
+
 ### Munin
 
 The Munin plugin location is at /munin (http://localhost:8080/munin).
@@ -259,6 +429,285 @@ process_start_time_seconds 1.54506833485e+09
 process_virtual_memory_bytes 1.15101696e+08
 ```
 
+### MQTT
+
+The MQTT client will publish updates to the given broker at the set topic.
+
+#### MQTT Configuration Options
+
+```bash
+--mqtt.enabled    Enable MQTT publishing. [$MQTT_ENABLED]
+--mqtt.broker=    Set the host port and scheme of the MQTT broker. (default: tcp://localhost:1883) [$MQTT_BROKER]
+--mqtt.client_id= Set the client ID for the MQTT connection. (default: inverter-gui) [$MQTT_CLIENT_ID]
+--mqtt.topic=     Set the MQTT topic updates published to. (default: invertergui/updates) [$MQTT_TOPIC]
+--mqtt.command_topic= Set the MQTT topic that receives write commands for Victron settings/RAM variables. (default: invertergui/settings/set) [$MQTT_COMMAND_TOPIC]
+--mqtt.status_topic=  Set the MQTT topic where write command status updates are published. (default: invertergui/settings/status) [$MQTT_STATUS_TOPIC]
+--mqtt.device_id= Set logical device ID used for per-device orchestration topics. (default: invertergui) [$MQTT_DEVICE_ID]
+--mqtt.history_size= Number of samples retained for rolling history summaries. (default: 120) [$MQTT_HISTORY_SIZE]
+--mqtt.ha.enabled Enable Home Assistant MQTT discovery integration. [$MQTT_HA_ENABLED]
+--mqtt.ha.discovery_prefix= Set Home Assistant MQTT discovery prefix. (default: homeassistant) [$MQTT_HA_DISCOVERY_PREFIX]
+--mqtt.ha.node_id= Set Home Assistant node ID used for discovery topics and unique IDs. (default: invertergui) [$MQTT_HA_NODE_ID]
+--mqtt.ha.device_name= Set Home Assistant device display name. (default: Victron Inverter) [$MQTT_HA_DEVICE_NAME]
+--mqtt.venus.enabled Enable Venus-style MQTT compatibility topics (N/W model). [$MQTT_VENUS_ENABLED]
+--mqtt.venus.portal_id= Set Venus portal ID segment used in N/W topics. (default: invertergui) [$MQTT_VENUS_PORTAL_ID]
+--mqtt.venus.service= Set Venus service segment used in N/W topics. (default: vebus/257) [$MQTT_VENUS_SERVICE]
+--mqtt.venus.subscribe_writes Subscribe to Venus W/... topics and map to MK2 commands. [$MQTT_VENUS_SUBSCRIBE_WRITES]
+--mqtt.username=  Set the MQTT username [$MQTT_USERNAME]
+--mqtt.password=  Set the MQTT password [$MQTT_PASSWORD]
+--mqtt.password-file= Path to a file containing the MQTT password [$MQTT_PASSWORD_FILE]
+```
+
+Related global option:
+
+```bash
+--read_only Disable all write operations and run in monitoring-only mode. [$READ_ONLY]
+```
+
+The MQTT client can be enabled by setting the environment variable `MQTT_ENABLED=true` or flag `--mqtt.enabled`.
+All MQTT configuration can be done via flags or as environment variables.
+The URI for the broker can be configured format should be `scheme://host:port`, where "scheme" is one of "tcp", "ssl", or "ws".
+
+When `--mqtt.command_topic` is configured, the application subscribes to that topic and accepts JSON write commands.
+The recommended command for inverter control follows the same model used by `victron-mk3`:
+
+```json
+{
+  "request_id": "optional-correlation-id",
+  "kind": "panel_state",
+  "switch": "on",
+  "current_limit": 16.5
+}
+```
+
+`switch` supports `charger_only`, `inverter_only`, `on`, and `off` (or numeric values `1..4`).
+`current_limit` is in amps and optional. If omitted, only the switch state is changed.
+To update only the current limit (while preserving the last known mode), send:
+
+```json
+{
+  "kind": "panel_state",
+  "current_limit": 12.0
+}
+```
+
+If no prior mode is known (for example on a fresh broker state), this command is rejected until a mode command is sent once.
+
+Standby can be controlled with:
+
+```json
+{
+  "kind": "standby",
+  "standby": true
+}
+```
+
+Low-level writes are still supported:
+
+```json
+{
+  "kind": "setting",
+  "id": 15,
+  "value": 1
+}
+```
+
+`kind` supports `panel_state`, `setting`, and `ram_var` (with aliases for each).  
+The result is published to `--mqtt.status_topic` with status `ok` or `error`.
+
+### MQTT Device Orchestration Topics
+
+For multi-device deployments on one MQTT broker, `invertergui` now also publishes
+device-scoped orchestration topics under:
+
+- `{topic-root}/devices/{device_id}/state`
+- `{topic-root}/devices/{device_id}/history/summary`
+- `{topic-root}/devices/{device_id}/alarms/active`
+
+Set `--mqtt.device_id` (or `MQTT_DEVICE_ID`) per inverter instance so each instance
+publishes to a unique device path.
+
+Rolling history depth for the summary window is set by `--mqtt.history_size`.
+
+### Venus-Style MQTT Compatibility
+
+Enable Venus-compatible topics with:
+
+```bash
+--mqtt.venus.enabled
+```
+
+When enabled, `invertergui` publishes Venus-style notifications to:
+
+- `N/{portal_id}/{service}/...`
+
+Defaults:
+
+- `portal_id`: `invertergui` (`--mqtt.venus.portal_id`)
+- `service`: `vebus/257` (`--mqtt.venus.service`)
+
+Published paths include common VE.Bus style values such as:
+
+- `Dc/0/Voltage`, `Dc/0/Current`, `Dc/0/Power`, `Soc`
+- `Ac/ActiveIn/L1/V`, `Ac/ActiveIn/L1/I`, `Ac/ActiveIn/L1/F`, `Ac/ActiveIn/L1/P`
+- `Ac/Out/L1/V`, `Ac/Out/L1/I`, `Ac/Out/L1/F`, `Ac/Out/L1/P`
+- alarm paths (`Alarms/LowBattery`, `Alarms/HighTemperature`, `Alarms/Overload`, `Alarms/Communication`)
+
+Optional write compatibility can be enabled with:
+
+```bash
+--mqtt.venus.subscribe_writes
+```
+
+This subscribes to:
+
+- `W/{portal_id}/{service}/#`
+
+and maps supported write paths to MK2 control operations:
+
+- `Mode` -> remote panel mode
+- `Ac/ActiveIn/CurrentLimit` -> remote panel current limit
+- `Settings/Standby` / `RemotePanel/Standby` -> standby control
+
+### Home Assistant
+
+Enable Home Assistant auto-discovery with:
+
+```bash
+--mqtt.ha.enabled
+```
+
+When enabled, `invertergui` publishes retained discovery payloads and availability under:
+
+- `{topic-root}/homeassistant/availability` (`online`/`offline`)
+- `{discovery_prefix}/sensor/{node_id}/.../config`
+- `{discovery_prefix}/binary_sensor/{node_id}/.../config`
+- `{discovery_prefix}/select/{node_id}/remote_panel_mode/config` (if command topic is configured)
+- `{discovery_prefix}/number/{node_id}/remote_panel_current_limit/config` (if command topic is configured)
+- `{discovery_prefix}/switch/{node_id}/remote_panel_standby/config` (if command topic is configured)
+
+The discovered entities include battery/input/output sensors, a data-valid diagnostic binary sensor,
+plus remote panel controls for:
+
+- `Remote Panel Mode` (`on`, `off`, `charger_only`, `inverter_only`)
+- `Remote Panel Current Limit` (AC input current limit in amps)
+- `Remote Panel Standby` (prevent device sleep while off)
+
+The combined mode + current limit behavior is provided through the `panel_state` MQTT command kind,
+which mirrors `victron_mk3.set_remote_panel_state`.
+
+### Home Assistant Custom Component (MQTT)
+
+This repository also includes a custom Home Assistant integration at:
+
+- `custom_components/victron_mk2_mqtt`
+
+This component is useful if you want HA entities/services that are explicitly tied to
+`invertergui` MQTT topics, instead of relying only on MQTT auto-discovery entities.
+
+If you use this custom component, you can disable `--mqtt.ha.enabled` in `invertergui`
+to avoid duplicate entities created by MQTT discovery.
+
+Install via HACS:
+
+1. Add the integration repository in Home Assistant:
+   [![Open your Home Assistant instance and open this repository inside the Home Assistant Community Store.](https://my.home-assistant.io/badges/hacs_repository.svg)](https://my.home-assistant.io/redirect/hacs_repository/?owner=nathan&repository=invertergui&category=integration)
+2. Install `Victron MK2 MQTT` from HACS.
+3. Restart Home Assistant.
+4. Add the YAML configuration shown below.
+
+If you are not mirroring this repo to GitHub, use the manual install method below.
+
+Manual install (alternative):
+
+```text
+<home-assistant-config>/custom_components/victron_mk2_mqtt
+```
+
+Then add YAML config:
+
+```yaml
+victron_mk2_mqtt:
+  name: Victron Inverter
+  state_topic: invertergui/updates
+  command_topic: invertergui/settings/set
+  status_topic: invertergui/settings/status
+  # topic_root is optional; defaults to state_topic root (for example "invertergui")
+  # topic_root: invertergui
+```
+
+Provided entities include:
+
+- Telemetry sensors (battery/input/output voltage/current/frequency and derived power)
+- `Remote Panel Mode` (`charger_only`, `inverter_only`, `on`, `off`)
+- `Remote Panel Current Limit` (A)
+- `Remote Panel Standby`
+- Diagnostic entities (`Data Valid`, `Last Command Error`)
+
+Service exposed by the integration:
+
+- `victron_mk2_mqtt.set_remote_panel_state`
+
+Example service call:
+
+```yaml
+service: victron_mk2_mqtt.set_remote_panel_state
+data:
+  mode: on
+  current_limit: 16.0
+```
+
+### Home Assistant MQTT-Only Dashboard (No Duplicate Entities)
+
+If you want the same control/telemetry experience but only via MQTT (without duplicate
+entities from discovery/custom integrations), use the packaged Home Assistant files:
+
+- MQTT entity + control package: `homeassistant/packages/invertergui_mqtt.yaml`
+- Lovelace dashboard: `homeassistant/dashboards/invertergui_mqtt_dashboard.yaml`
+
+The package assumes default topics (`invertergui/updates`, `invertergui/settings/set`,
+`invertergui/settings/status`). If you use custom MQTT topics, update those values in
+`homeassistant/packages/invertergui_mqtt.yaml`.
+
+Recommended for this mode:
+
+- Disable MQTT discovery output from `invertergui` (`--mqtt.ha.enabled=false`)
+- Do not enable the `victron_mk2_mqtt` custom component at the same time
+
+1. Ensure HA packages are enabled (if not already):
+
+```yaml
+homeassistant:
+  packages: !include_dir_named packages
+```
+
+2. Copy package file to your HA config:
+
+```text
+<home-assistant-config>/packages/invertergui_mqtt.yaml
+```
+
+3. Copy dashboard file to your HA config:
+
+```text
+<home-assistant-config>/dashboards/invertergui_mqtt_dashboard.yaml
+```
+
+4. Register the dashboard (YAML mode example):
+
+```yaml
+lovelace:
+  mode: storage
+  dashboards:
+    invertergui-victron:
+      mode: yaml
+      title: Victron MQTT
+      icon: mdi:flash
+      show_in_sidebar: true
+      filename: dashboards/invertergui_mqtt_dashboard.yaml
+```
+
+5. Restart Home Assistant.
+
 ## TTY Device
 
 The intertergui application makes use of a serial tty device to monitor the Multiplus.
@@ -320,4 +769,4 @@ The last four lines are optional, but is useful when debugging and logging conne
 
 This repos includes a [Grafana](https://grafana.com/) dashboard in the [grafana folder](./grafana/prometheus-dashboard.json) that you can import. This is useful if you are using prometheus to log your data and want to display it in a nice way.
 
-![grafana](https://rawcdn.githack.com/diebietse/invertergui/e20f8fb9161758cd12de95d675aee0ed2e044d8e/grafana/dashboard.png "Grafana Dashboard")
+![grafana](./grafana/dashboard.png "Grafana Dashboard")

cmd/invertergui/config.go

@@ -0,0 +1,98 @@
+package main
+
+import (
+	"fmt"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/jessevdk/go-flags"
+)
+
+type config struct {
+	Address  string `long:"address" env:"ADDRESS" default:":8080" description:"The IP/DNS and port of the machine that the application is running on."`
+	ReadOnly bool   `long:"read_only" env:"READ_ONLY" description:"Disable all write operations and run in monitoring-only mode."`
+	Control  struct {
+		Profile               string        `long:"control.profile" env:"CONTROL_PROFILE" default:"normal" description:"Write policy profile: normal, maintenance, or read_only."`
+		MaxCurrentLimit       float64       `long:"control.max_current_limit" env:"CONTROL_MAX_CURRENT_LIMIT" default:"0" description:"Optional max AC current limit guardrail in amps (0 disables)."`
+		ModeChangeMinInterval time.Duration `long:"control.mode_change_min_interval" env:"CONTROL_MODE_CHANGE_MIN_INTERVAL" default:"3s" description:"Minimum time between mode changes."`
+		LockoutWindow         time.Duration `long:"control.lockout_window" env:"CONTROL_LOCKOUT_WINDOW" default:"0s" description:"Post-command lockout window for command arbitration."`
+		AllowedPanelModes     string        `long:"control.allowed_panel_modes" env:"CONTROL_ALLOWED_PANEL_MODES" default:"" description:"Comma-separated allowlist of remote panel modes. Supported values: on, off, charger_only, inverter_only. Empty allows all modes."`
+	}
+	Data struct {
+		Source string `long:"data.source" env:"DATA_SOURCE" default:"serial" description:"Set the source of data for the inverter gui. \"serial\", \"tcp\" or \"mock\""`
+		Host   string `long:"data.host" env:"DATA_HOST" default:"localhost:8139" description:"Host to connect when source is set to tcp."`
+		Device string `long:"data.device" env:"DATA_DEVICE" default:"/dev/ttyUSB0" description:"TTY device to use when source is set to serial."`
+	}
+	Cli struct {
+		Enabled bool `long:"cli.enabled" env:"CLI_ENABLED" description:"Enable CLI output."`
+	}
+	MQTT struct {
+		Enabled      bool   `long:"mqtt.enabled" env:"MQTT_ENABLED" description:"Enable MQTT publishing."`
+		Broker       string `long:"mqtt.broker" env:"MQTT_BROKER" default:"tcp://localhost:1883" description:"Set the host port and scheme of the MQTT broker."`
+		ClientID     string `long:"mqtt.client_id" env:"MQTT_CLIENT_ID" default:"inverter-gui" description:"Set the client ID for the MQTT connection."`
+		Topic        string `long:"mqtt.topic" env:"MQTT_TOPIC" default:"invertergui/updates" description:"Set the MQTT topic updates published to."`
+		CommandTopic string `long:"mqtt.command_topic" env:"MQTT_COMMAND_TOPIC" default:"invertergui/settings/set" description:"Set the MQTT topic that receives write commands for Victron settings/RAM variables."`
+		StatusTopic  string `long:"mqtt.status_topic" env:"MQTT_STATUS_TOPIC" default:"invertergui/settings/status" description:"Set the MQTT topic where write command status updates are published."`
+		DeviceID     string `long:"mqtt.device_id" env:"MQTT_DEVICE_ID" default:"invertergui" description:"Set the logical device ID used for per-device orchestration topics."`
+		HistorySize  int    `long:"mqtt.history_size" env:"MQTT_HISTORY_SIZE" default:"120" description:"Number of telemetry samples retained for rolling history summaries."`
+		InstanceID   int    `long:"mqtt.instance_id" env:"MQTT_INSTANCE_ID" default:"0" description:"Device instance ID for multi-device orchestration and Venus compatibility."`
+		Phase        string `long:"mqtt.phase" env:"MQTT_PHASE" default:"L1" description:"Electrical phase label for this instance (L1/L2/L3)."`
+		PhaseGroup   string `long:"mqtt.phase_group" env:"MQTT_PHASE_GROUP" default:"default" description:"Grouping key for parallel/3-phase system aggregation topics."`
+		HA           struct {
+			Enabled         bool   `long:"mqtt.ha.enabled" env:"MQTT_HA_ENABLED" description:"Enable Home Assistant MQTT discovery integration."`
+			DiscoveryPrefix string `long:"mqtt.ha.discovery_prefix" env:"MQTT_HA_DISCOVERY_PREFIX" default:"homeassistant" description:"Set Home Assistant MQTT discovery prefix."`
+			NodeID          string `long:"mqtt.ha.node_id" env:"MQTT_HA_NODE_ID" default:"invertergui" description:"Set Home Assistant node ID used for discovery topics and unique IDs."`
+			DeviceName      string `long:"mqtt.ha.device_name" env:"MQTT_HA_DEVICE_NAME" default:"Victron Inverter" description:"Set Home Assistant device display name."`
+		}
+		Venus struct {
+			Enabled         bool   `long:"mqtt.venus.enabled" env:"MQTT_VENUS_ENABLED" description:"Enable Venus-style MQTT compatibility topics (N/W topic model)."`
+			PortalID        string `long:"mqtt.venus.portal_id" env:"MQTT_VENUS_PORTAL_ID" default:"invertergui" description:"Set Venus portal ID segment used in N/W topics."`
+			Service         string `long:"mqtt.venus.service" env:"MQTT_VENUS_SERVICE" default:"vebus/257" description:"Set Venus service segment used in N/W topics."`
+			SubscribeWrites bool   `long:"mqtt.venus.subscribe_writes" env:"MQTT_VENUS_SUBSCRIBE_WRITES" description:"Subscribe to Venus write topics and map them to MK2 control commands."`
+			TopicPrefix     string `long:"mqtt.venus.topic_prefix" env:"MQTT_VENUS_TOPIC_PREFIX" default:"" description:"Optional topic prefix before Venus N/W topics, for example 'victron'."`
+			GuideCompat     bool   `long:"mqtt.venus.guide_compat" env:"MQTT_VENUS_GUIDE_COMPAT" description:"Enable guide-style settings/0/Settings/CGwacs compatibility paths for Home Assistant controls."`
+		}
+		Username     string `long:"mqtt.username" env:"MQTT_USERNAME" default:"" description:"Set the MQTT username"`
+		Password     string `long:"mqtt.password" env:"MQTT_PASSWORD" default:"" description:"Set the MQTT password"`
+		PasswordFile string `long:"mqtt.password-file" env:"MQTT_PASSWORD_FILE" default:"" description:"Path to a file containing the MQTT password"`
+	}
+	Loglevel string `long:"loglevel" env:"LOGLEVEL" default:"info" description:"The log level to generate logs at. (\"panic\", \"fatal\", \"error\", \"warn\", \"info\", \"debug\", \"trace\")"`
+}
+
+func parseConfig() (*config, error) {
+	conf := &config{}
+	// go-flags bool options cannot use struct-tag defaults; keep intended behavior via struct initialization.
+	conf.MQTT.Venus.SubscribeWrites = true
+	conf.MQTT.Venus.GuideCompat = true
+	parser := flags.NewParser(conf, flags.Default)
+	if _, err := parser.Parse(); err != nil {
+		return nil, err
+	}
+	if err := resolvePasswordFile(conf); err != nil {
+		return nil, err
+	}
+	return conf, nil
+}
+
+func resolvePasswordFile(conf *config) error {
+	if conf.MQTT.PasswordFile != "" && conf.MQTT.Password != "" {
+		return fmt.Errorf("mqtt.password and mqtt.password-file are mutually exclusive")
+	}
+	if conf.MQTT.PasswordFile != "" {
+		password, err := readPasswordFile(conf.MQTT.PasswordFile)
+		if err != nil {
+			return err
+		}
+		conf.MQTT.Password = password
+	}
+	return nil
+}
+
+func readPasswordFile(path string) (string, error) {
+	data, err := os.ReadFile(path)
+	if err != nil {
+		return "", fmt.Errorf("could not read MQTT password file: %w", err)
+	}
+	return strings.TrimRight(string(data), "\n\r"), nil
+}

cmd/invertergui/config_test.go

@@ -0,0 +1,107 @@
+package main
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+)
+
+const testInlineSecret = "inline-secret"
+
+func TestReadPasswordFile(t *testing.T) {
+	tests := []struct {
+		name     string
+		content  string
+		expected string
+	}{
+		{
+			name:     "plain password",
+			content:  "secret",
+			expected: "secret",
+		},
+		{
+			name:     "password with trailing newline",
+			content:  "secret\n",
+			expected: "secret",
+		},
+		{
+			name:     "password with trailing carriage return and newline",
+			content:  "secret\r\n",
+			expected: "secret",
+		},
+		{
+			name:     "empty file",
+			content:  "",
+			expected: "",
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			path := filepath.Join(t.TempDir(), "password")
+			if err := os.WriteFile(path, []byte(tt.content), 0o600); err != nil {
+				t.Fatalf("failed to write test file: %v", err)
+			}
+
+			got, err := readPasswordFile(path)
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			if got != tt.expected {
+				t.Errorf("got %q, want %q", got, tt.expected)
+			}
+		})
+	}
+}
+
+func TestReadPasswordFile_NotFound(t *testing.T) {
+	_, err := readPasswordFile("/nonexistent/path/password")
+	if err == nil {
+		t.Fatal("expected error for missing file, got nil")
+	}
+}
+
+func TestResolvePassword_MutuallyExclusive(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "password")
+	if err := os.WriteFile(path, []byte("secret"), 0o600); err != nil {
+		t.Fatalf("failed to write test file: %v", err)
+	}
+
+	conf := &config{}
+	conf.MQTT.Password = testInlineSecret
+	conf.MQTT.PasswordFile = path
+
+	err := resolvePasswordFile(conf)
+	if err == nil {
+		t.Fatal("expected error when both mqtt.password and mqtt.password-file are set, got nil")
+	}
+}
+
+func TestResolvePassword_FromFile(t *testing.T) {
+	path := filepath.Join(t.TempDir(), "password")
+	if err := os.WriteFile(path, []byte("file-secret\n"), 0o600); err != nil {
+		t.Fatalf("failed to write test file: %v", err)
+	}
+
+	conf := &config{}
+	conf.MQTT.PasswordFile = path
+
+	if err := resolvePasswordFile(conf); err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if conf.MQTT.Password != "file-secret" {
+		t.Errorf("got %q, want %q", conf.MQTT.Password, "file-secret")
+	}
+}
+
+func TestResolvePassword_NoFile(t *testing.T) {
+	conf := &config{}
+	conf.MQTT.Password = testInlineSecret
+
+	if err := resolvePasswordFile(conf); err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if conf.MQTT.Password != testInlineSecret {
+		t.Errorf("got %q, want %q", conf.MQTT.Password, testInlineSecret)
+	}
+}

cmd/invertergui/main.go

@@ -31,90 +31,287 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 package main
 
 import (
-	"flag"
+	"fmt"
 	"io"
-	"log"
 	"net"
 	"net/http"
 	"os"
+	"sort"
+	"strings"
 
-	"github.com/diebietse/invertergui/mk2core"
-	"github.com/diebietse/invertergui/mk2driver"
-	"github.com/diebietse/invertergui/plugins/cli"
-	"github.com/diebietse/invertergui/plugins/munin"
-	"github.com/diebietse/invertergui/plugins/prometheus"
-	"github.com/diebietse/invertergui/plugins/webui"
-	"github.com/diebietse/invertergui/plugins/webui/static"
+	"git.coadcorp.com/nathan/invertergui/mk2core"
+	"git.coadcorp.com/nathan/invertergui/mk2driver"
+	"git.coadcorp.com/nathan/invertergui/plugins/cli"
+	"git.coadcorp.com/nathan/invertergui/plugins/mqttclient"
+	"git.coadcorp.com/nathan/invertergui/plugins/munin"
+	"git.coadcorp.com/nathan/invertergui/plugins/prometheus"
+	"git.coadcorp.com/nathan/invertergui/plugins/webui"
+	"git.coadcorp.com/nathan/invertergui/plugins/webui/static"
 	"github.com/prometheus/client_golang/prometheus/promhttp"
+	"github.com/sirupsen/logrus"
 	"github.com/tarm/serial"
 )
 
-func main() {
-	source := flag.String("source", "serial", "Set the source of data for the inverter gui. \"serial\", \"tcp\" or \"mock\"")
-	addr := flag.String("addr", ":8080", "TCP address to listen on.")
-	ip := flag.String("ip", "localhost:8139", "IP to connect when using tcp connection.")
-	dev := flag.String("dev", "/dev/ttyUSB0", "TTY device to use.")
-	cliEnable := flag.Bool("cli", false, "Enable CLI output")
-	flag.Parse()
+var log = logrus.WithField("ctx", "inverter-gui")
 
-	mk2 := getMk2Device(*source, *ip, *dev)
+func main() {
+	conf, err := parseConfig()
+	if err != nil {
+		log.WithError(err).Error("Could not parse configuration")
+		os.Exit(1)
+	}
+	log.Info("Starting invertergui")
+	logLevel, err := logrus.ParseLevel(conf.Loglevel)
+	if err != nil {
+		log.Fatalf("Could not parse log level: %v", err)
+	}
+	logrus.SetLevel(logLevel)
+	log.WithFields(logrus.Fields{
+		"loglevel":           conf.Loglevel,
+		"address":            conf.Address,
+		"read_only":          conf.ReadOnly,
+		"data_source":        conf.Data.Source,
+		"data_host":          conf.Data.Host,
+		"data_device":        conf.Data.Device,
+		"cli_enabled":        conf.Cli.Enabled,
+		"mqtt_enabled":       conf.MQTT.Enabled,
+		"mqtt_broker":        conf.MQTT.Broker,
+		"mqtt_topic":         conf.MQTT.Topic,
+		"mqtt_command_topic": conf.MQTT.CommandTopic,
+		"mqtt_status_topic":  conf.MQTT.StatusTopic,
+		"mqtt_device_id":     conf.MQTT.DeviceID,
+		"mqtt_history_size":  conf.MQTT.HistorySize,
+		"mqtt_ha_enabled":    conf.MQTT.HA.Enabled,
+		"mqtt_venus_enabled": conf.MQTT.Venus.Enabled,
+		"mqtt_venus_portal":  conf.MQTT.Venus.PortalID,
+		"mqtt_venus_service": conf.MQTT.Venus.Service,
+		"mqtt_venus_prefix":  conf.MQTT.Venus.TopicPrefix,
+		"mqtt_venus_guide":   conf.MQTT.Venus.GuideCompat,
+		"control_profile":    conf.Control.Profile,
+		"control_modes":      conf.Control.AllowedPanelModes,
+	}).Info("Configuration loaded")
+
+	mk2, err := getMk2Device(conf.Data.Source, conf.Data.Host, conf.Data.Device)
+	if err != nil {
+		log.Fatalf("Could not open data source: %v", err)
+	}
 	defer mk2.Close()
+	log.Info("MK2 device connection established")
 
 	core := mk2core.NewCore(mk2)
 
-	if *cliEnable {
+	if conf.Cli.Enabled {
+		log.Info("CLI plugin enabled")
 		cli.NewCli(core.NewSubscription())
 	}
 
 	// Webgui
-	gui := webui.NewWebGui(core.NewSubscription())
+	var writer mk2driver.SettingsWriter
+	if w, ok := mk2.(mk2driver.SettingsWriter); ok {
+		writer = w
+		log.Info("MK2 data source supports settings writes")
+	} else {
+		log.Warn("MK2 data source does not support settings writes")
+	}
+	if conf.ReadOnly {
+		if writer != nil {
+			log.Warn("READ_ONLY enabled; disabling all write operations")
+		} else {
+			log.Info("READ_ONLY enabled")
+		}
+		writer = nil
+	} else if writer != nil {
+		allowedPanelStates, allowedPanelModeNames, parseErr := parseAllowedPanelModes(conf.Control.AllowedPanelModes)
+		if parseErr != nil {
+			log.WithError(parseErr).Fatal("Invalid control.allowed_panel_modes configuration")
+		}
+
+		policyProfile := mk2driver.WriterProfile(strings.ToLower(strings.TrimSpace(conf.Control.Profile)))
+		if policyProfile == "" {
+			policyProfile = mk2driver.WriterProfileNormal
+		}
+		if policyProfile != mk2driver.WriterProfileNormal &&
+			policyProfile != mk2driver.WriterProfileMaintenance &&
+			policyProfile != mk2driver.WriterProfileReadOnly {
+			log.WithField("profile", conf.Control.Profile).Warn("Unknown control profile; defaulting to normal")
+			policyProfile = mk2driver.WriterProfileNormal
+		}
+
+		var maxCurrentLimit *float64
+		if conf.Control.MaxCurrentLimit > 0 {
+			limit := conf.Control.MaxCurrentLimit
+			maxCurrentLimit = &limit
+		}
+
+		writer = mk2driver.NewManagedWriter(writer, mk2driver.WriterPolicy{
+			Profile:               policyProfile,
+			MaxCurrentLimitA:      maxCurrentLimit,
+			ModeChangeMinInterval: conf.Control.ModeChangeMinInterval,
+			LockoutWindow:         conf.Control.LockoutWindow,
+			AllowedPanelStates:    allowedPanelStates,
+		})
+
+		allowedModes := "all"
+		if len(allowedPanelModeNames) > 0 {
+			allowedModes = strings.Join(allowedPanelModeNames, ",")
+		}
+		log.WithFields(logrus.Fields{
+			"profile":                  policyProfile,
+			"max_current_limit":        conf.Control.MaxCurrentLimit,
+			"mode_change_min_interval": conf.Control.ModeChangeMinInterval,
+			"lockout_window":           conf.Control.LockoutWindow,
+			"allowed_panel_modes":      allowedModes,
+		}).Info("Write policy/arbitration layer enabled")
+	}
+	gui := webui.NewWebGui(core.NewSubscription(), writer)
 	http.Handle("/", static.New())
 	http.Handle("/ws", http.HandlerFunc(gui.ServeHub))
+	http.Handle("/api/remote-panel/state", http.HandlerFunc(gui.ServeRemotePanelState))
+	http.Handle("/api/remote-panel/standby", http.HandlerFunc(gui.ServeRemotePanelStandby))
+	log.Info("Web UI routes registered")
 
 	// Munin
 	mu := munin.NewMunin(core.NewSubscription())
 	http.Handle("/munin", http.HandlerFunc(mu.ServeMuninHTTP))
 	http.Handle("/muninconfig", http.HandlerFunc(mu.ServeMuninConfigHTTP))
+	log.Info("Munin routes registered")
 
 	// Prometheus
 	prometheus.NewPrometheus(core.NewSubscription())
 	http.Handle("/metrics", promhttp.Handler())
+	log.Info("Prometheus route registered")
 
-	log.Fatal(http.ListenAndServe(*addr, nil))
+	// MQTT
+	if conf.MQTT.Enabled {
+		mqttConf := mqttclient.Config{
+			Broker:       conf.MQTT.Broker,
+			Topic:        conf.MQTT.Topic,
+			CommandTopic: conf.MQTT.CommandTopic,
+			StatusTopic:  conf.MQTT.StatusTopic,
+			ClientID:     conf.MQTT.ClientID,
+			DeviceID:     conf.MQTT.DeviceID,
+			HistorySize:  conf.MQTT.HistorySize,
+			InstanceID:   conf.MQTT.InstanceID,
+			Phase:        conf.MQTT.Phase,
+			PhaseGroup:   conf.MQTT.PhaseGroup,
+			HomeAssistant: mqttclient.HomeAssistantConfig{
+				Enabled:         conf.MQTT.HA.Enabled,
+				DiscoveryPrefix: conf.MQTT.HA.DiscoveryPrefix,
+				NodeID:          conf.MQTT.HA.NodeID,
+				DeviceName:      conf.MQTT.HA.DeviceName,
+			},
+			Venus: mqttclient.VenusConfig{
+				Enabled:         conf.MQTT.Venus.Enabled,
+				PortalID:        conf.MQTT.Venus.PortalID,
+				Service:         conf.MQTT.Venus.Service,
+				SubscribeWrites: conf.MQTT.Venus.SubscribeWrites,
+				TopicPrefix:     conf.MQTT.Venus.TopicPrefix,
+				GuideCompat:     conf.MQTT.Venus.GuideCompat,
+			},
+			Username: conf.MQTT.Username,
+			Password: conf.MQTT.Password,
+		}
+		if writer == nil {
+			log.Warn("MK2 data source does not support write commands; MQTT command topic will be ignored")
+		}
+		if err := mqttclient.New(core.NewSubscription(), writer, mqttConf); err != nil {
+			log.Fatalf("Could not setup MQTT client: %v", err)
+		}
+		log.Info("MQTT client initialized")
+	}
+	log.Infof("Invertergui web server starting on: %v", conf.Address)
+
+	if err := http.ListenAndServe(conf.Address, nil); err != nil {
+		log.Fatal(err)
+	}
 }
 
-func getMk2Device(source, ip, dev string) mk2driver.Mk2 {
+func getMk2Device(source, ip, dev string) (mk2driver.Mk2, error) {
 	var p io.ReadWriteCloser
 	var err error
 	var tcpAddr *net.TCPAddr
 
 	switch source {
 	case "serial":
+		log.WithField("device", dev).Info("Opening serial MK2 source")
 		serialConfig := &serial.Config{Name: dev, Baud: 2400}
 		p, err = serial.OpenPort(serialConfig)
 		if err != nil {
-			panic(err)
+			return nil, err
 		}
 	case "tcp":
+		log.WithField("host", ip).Info("Opening TCP MK2 source")
 		tcpAddr, err = net.ResolveTCPAddr("tcp", ip)
 		if err != nil {
-			panic(err)
+			return nil, err
 		}
 		p, err = net.DialTCP("tcp", nil, tcpAddr)
 		if err != nil {
-			panic(err)
+			return nil, err
 		}
 	case "mock":
-		return mk2driver.NewMk2Mock()
+		log.Info("Using mock MK2 data source")
+		return mk2driver.NewMk2Mock(), nil
 	default:
-		log.Printf("Invalid source selection: %v\nUse \"serial\", \"tcp\" or \"mock\"", source)
-		os.Exit(1)
+		return nil, fmt.Errorf("Invalid source selection: %v\nUse \"serial\", \"tcp\" or \"mock\"", source)
 	}
 
 	mk2, err := mk2driver.NewMk2Connection(p)
 	if err != nil {
-		panic(err)
+		return nil, err
+	}
+	log.WithField("source", source).Info("MK2 connection ready")
+
+	return mk2, nil
+}
+
+func parseAllowedPanelModes(raw string) (map[mk2driver.PanelSwitchState]struct{}, []string, error) {
+	if strings.TrimSpace(raw) == "" {
+		return nil, nil, nil
 	}
 
-	return mk2
+	out := make(map[mk2driver.PanelSwitchState]struct{})
+	names := make([]string, 0, 4)
+
+	for _, token := range strings.Split(raw, ",") {
+		mode := strings.ToLower(strings.TrimSpace(token))
+		if mode == "" {
+			continue
+		}
+
+		var state mk2driver.PanelSwitchState
+		var canonical string
+
+		switch mode {
+		case "on":
+			state = mk2driver.PanelSwitchOn
+			canonical = "on"
+		case "off":
+			state = mk2driver.PanelSwitchOff
+			canonical = "off"
+		case "charger_only", "charger-only":
+			state = mk2driver.PanelSwitchChargerOnly
+			canonical = "charger_only"
+		case "inverter_only", "inverter-only":
+			state = mk2driver.PanelSwitchInverterOnly
+			canonical = "inverter_only"
+		default:
+			return nil, nil, fmt.Errorf(
+				"unsupported panel mode %q in control.allowed_panel_modes; supported values: on, off, charger_only, inverter_only",
+				token,
+			)
+		}
+
+		if _, exists := out[state]; !exists {
+			out[state] = struct{}{}
+			names = append(names, canonical)
+		}
+	}
+
+	if len(out) == 0 {
+		return nil, nil, fmt.Errorf("control.allowed_panel_modes is set but no valid modes were provided")
+	}
+
+	sort.Strings(names)
+	return out, names, nil
 }

cmd/invertergui/main_test.go

@@ -0,0 +1,46 @@
+package main
+
+import (
+	"testing"
+
+	"git.coadcorp.com/nathan/invertergui/mk2driver"
+)
+
+func TestParseAllowedPanelModesEmpty(t *testing.T) {
+	states, names, err := parseAllowedPanelModes("")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if states != nil {
+		t.Fatalf("expected nil state map for empty input, got %#v", states)
+	}
+	if names != nil {
+		t.Fatalf("expected nil names for empty input, got %#v", names)
+	}
+}
+
+func TestParseAllowedPanelModesValid(t *testing.T) {
+	states, names, err := parseAllowedPanelModes("off, charger-only,off")
+	if err != nil {
+		t.Fatalf("unexpected error: %v", err)
+	}
+	if len(states) != 2 {
+		t.Fatalf("expected 2 allowed states, got %d", len(states))
+	}
+	if _, ok := states[mk2driver.PanelSwitchOff]; !ok {
+		t.Fatalf("off should be allowed")
+	}
+	if _, ok := states[mk2driver.PanelSwitchChargerOnly]; !ok {
+		t.Fatalf("charger_only should be allowed")
+	}
+	if len(names) != 2 {
+		t.Fatalf("expected 2 names, got %d", len(names))
+	}
+}
+
+func TestParseAllowedPanelModesInvalid(t *testing.T) {
+	_, _, err := parseAllowedPanelModes("off,invalid_mode")
+	if err == nil {
+		t.Fatal("expected error for invalid mode")
+	}
+}

custom_components/victron_mk2_mqtt/__init__.py

@@ -0,0 +1,186 @@
+"""Home Assistant integration for invertergui MQTT topics."""
+
+from __future__ import annotations
+
+from typing import Any
+
+import voluptuous as vol
+from homeassistant.const import CONF_NAME
+from homeassistant.core import HomeAssistant, ServiceCall
+from homeassistant.exceptions import HomeAssistantError
+from homeassistant.helpers import config_validation as cv, discovery
+from homeassistant.helpers.typing import ConfigType
+
+from .const import (
+    ATTR_ESS_MAX_CHARGE_POWER,
+    ATTR_ESS_MAX_DISCHARGE_POWER,
+    ATTR_ESS_MODE,
+    ATTR_ESS_SETPOINT,
+    ATTR_CURRENT_LIMIT,
+    ATTR_MODE,
+    CONF_COMMAND_TOPIC,
+    CONF_STATE_TOPIC,
+    CONF_STATUS_TOPIC,
+    CONF_TOPIC_ROOT,
+    CONF_VENUS_GUIDE_COMPAT,
+    CONF_VENUS_PORTAL_ID,
+    CONF_VENUS_TOPIC_PREFIX,
+    DATA_BRIDGE,
+    DEFAULT_COMMAND_TOPIC,
+    DEFAULT_NAME,
+    DEFAULT_STATE_TOPIC,
+    DEFAULT_STATUS_TOPIC,
+    DEFAULT_TOPIC_ROOT,
+    DEFAULT_VENUS_GUIDE_COMPAT,
+    DEFAULT_VENUS_PORTAL_ID,
+    DEFAULT_VENUS_TOPIC_PREFIX,
+    DOMAIN,
+    PANEL_MODES,
+    PLATFORMS,
+    SERVICE_SET_ESS_CONTROL,
+    SERVICE_SET_REMOTE_PANEL_STATE,
+)
+from .coordinator import VictronMqttBridge
+
+CONFIG_SCHEMA = vol.Schema(
+    {
+        DOMAIN: vol.Schema(
+            {
+                vol.Optional(CONF_NAME, default=DEFAULT_NAME): cv.string,
+                vol.Optional(CONF_STATE_TOPIC, default=DEFAULT_STATE_TOPIC): cv.string,
+                vol.Optional(
+                    CONF_COMMAND_TOPIC, default=DEFAULT_COMMAND_TOPIC
+                ): cv.string,
+                vol.Optional(CONF_STATUS_TOPIC, default=DEFAULT_STATUS_TOPIC): cv.string,
+                vol.Optional(CONF_TOPIC_ROOT): cv.string,
+                vol.Optional(CONF_VENUS_PORTAL_ID, default=DEFAULT_VENUS_PORTAL_ID): cv.string,
+                vol.Optional(CONF_VENUS_TOPIC_PREFIX, default=DEFAULT_VENUS_TOPIC_PREFIX): cv.string,
+                vol.Optional(CONF_VENUS_GUIDE_COMPAT, default=DEFAULT_VENUS_GUIDE_COMPAT): cv.boolean,
+            }
+        )
+    },
+    extra=vol.ALLOW_EXTRA,
+)
+
+SERVICE_SET_REMOTE_PANEL_STATE_SCHEMA = vol.Schema(
+    {
+        vol.Optional(ATTR_MODE): vol.In(PANEL_MODES),
+        vol.Optional(ATTR_CURRENT_LIMIT): vol.Coerce(float),
+    },
+    extra=vol.PREVENT_EXTRA,
+)
+
+SERVICE_SET_ESS_CONTROL_SCHEMA = vol.Schema(
+    {
+        vol.Optional(ATTR_ESS_SETPOINT): vol.Coerce(float),
+        vol.Optional(ATTR_ESS_MAX_CHARGE_POWER): vol.Coerce(float),
+        vol.Optional(ATTR_ESS_MAX_DISCHARGE_POWER): vol.Coerce(float),
+        vol.Optional(ATTR_ESS_MODE): vol.Coerce(int),
+    },
+    extra=vol.PREVENT_EXTRA,
+)
+
+
+def mqtt_topic_root(topic: str) -> str:
+    """Match invertergui MQTT root behavior."""
+    cleaned = topic.strip().strip("/")
+    if not cleaned:
+        return DEFAULT_TOPIC_ROOT
+    if cleaned.endswith("/updates"):
+        root = cleaned[: -len("/updates")]
+        if root:
+            return root
+    return cleaned
+
+
+async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
+    """Set up Victron MK2 MQTT integration from YAML."""
+    conf = config.get(DOMAIN)
+    if conf is None:
+        return True
+
+    setup_conf: dict[str, Any] = dict(conf)
+    if not setup_conf.get(CONF_TOPIC_ROOT):
+        setup_conf[CONF_TOPIC_ROOT] = mqtt_topic_root(setup_conf[CONF_STATE_TOPIC])
+
+    bridge = VictronMqttBridge(hass, setup_conf)
+    await bridge.async_setup()
+
+    hass.data.setdefault(DOMAIN, {})
+    hass.data[DOMAIN][DATA_BRIDGE] = bridge
+
+    await _register_services(hass, bridge)
+
+    for platform in PLATFORMS:
+        hass.async_create_task(
+            discovery.async_load_platform(hass, platform, DOMAIN, {}, config)
+        )
+
+    return True
+
+
+async def _register_services(hass: HomeAssistant, bridge: VictronMqttBridge) -> None:
+    """Register integration services."""
+    if hass.services.has_service(DOMAIN, SERVICE_SET_REMOTE_PANEL_STATE):
+        return
+
+    async def handle_set_remote_panel_state(call: ServiceCall) -> None:
+        mode = call.data.get(ATTR_MODE)
+        current_limit = call.data.get(ATTR_CURRENT_LIMIT)
+
+        if mode is None and current_limit is None:
+            raise HomeAssistantError("Provide at least one of mode or current_limit")
+        if current_limit is not None and current_limit < 0:
+            raise HomeAssistantError("current_limit must be >= 0")
+
+        payload: dict[str, Any] = {"kind": "panel_state"}
+        if mode is not None:
+            payload["switch"] = mode
+        if current_limit is not None:
+            payload["current_limit"] = float(current_limit)
+
+        await bridge.async_publish_command(payload)
+
+    hass.services.async_register(
+        DOMAIN,
+        SERVICE_SET_REMOTE_PANEL_STATE,
+        handle_set_remote_panel_state,
+        schema=SERVICE_SET_REMOTE_PANEL_STATE_SCHEMA,
+    )
+
+    async def handle_set_ess_control(call: ServiceCall) -> None:
+        setpoint = call.data.get(ATTR_ESS_SETPOINT)
+        max_charge = call.data.get(ATTR_ESS_MAX_CHARGE_POWER)
+        max_discharge = call.data.get(ATTR_ESS_MAX_DISCHARGE_POWER)
+        ess_mode = call.data.get(ATTR_ESS_MODE)
+
+        if all(value is None for value in (setpoint, max_charge, max_discharge, ess_mode)):
+            raise HomeAssistantError(
+                "Provide at least one of ess_setpoint, ess_max_charge_power, ess_max_discharge_power, or ess_mode"
+            )
+        if max_charge is not None and max_charge < 0:
+            raise HomeAssistantError("ess_max_charge_power must be >= 0")
+        if max_discharge is not None and max_discharge < 0:
+            raise HomeAssistantError("ess_max_discharge_power must be >= 0")
+        if ess_mode is not None and ess_mode not in (9, 10):
+            raise HomeAssistantError("ess_mode must be 9 or 10")
+
+        commands: list[dict[str, Any]] = []
+        if setpoint is not None:
+            commands.append({"kind": "ess_setpoint", "value": float(setpoint)})
+        if max_charge is not None:
+            commands.append({"kind": "ess_max_charge_power", "value": float(max_charge)})
+        if max_discharge is not None:
+            commands.append({"kind": "ess_max_discharge_power", "value": float(max_discharge)})
+        if ess_mode is not None:
+            commands.append({"kind": "ess_mode", "value": int(ess_mode)})
+
+        for payload in commands:
+            await bridge.async_publish_command(payload)
+
+    hass.services.async_register(
+        DOMAIN,
+        SERVICE_SET_ESS_CONTROL,
+        handle_set_ess_control,
+        schema=SERVICE_SET_ESS_CONTROL_SCHEMA,
+    )

custom_components/victron_mk2_mqtt/binary_sensor.py

@@ -0,0 +1,48 @@
+"""Binary sensors for Victron MK2 MQTT integration."""
+
+from __future__ import annotations
+
+from typing import Any
+
+from homeassistant.components.binary_sensor import BinarySensorEntity
+from homeassistant.const import EntityCategory
+from homeassistant.core import HomeAssistant
+
+from .const import DATA_BRIDGE, DOMAIN
+from .coordinator import VictronMqttBridge
+from .entity import VictronMqttEntity
+
+
+async def async_setup_platform(
+    hass: HomeAssistant,
+    config: dict[str, Any],
+    async_add_entities,
+    discovery_info: dict[str, Any] | None = None,
+) -> None:
+    """Set up Victron binary sensors."""
+    bridge: VictronMqttBridge = hass.data[DOMAIN][DATA_BRIDGE]
+    async_add_entities([VictronDataValidBinarySensor(bridge)])
+
+
+class VictronDataValidBinarySensor(VictronMqttEntity, BinarySensorEntity):
+    """MQTT data validity sensor."""
+
+    _attr_name = "Data Valid"
+    _attr_entity_category = EntityCategory.DIAGNOSTIC
+    _attr_icon = "mdi:check-network-outline"
+
+    def __init__(self, bridge: VictronMqttBridge) -> None:
+        super().__init__(bridge)
+        self._attr_unique_id = f"{bridge.topic_root}_data_valid"
+
+    @property
+    def is_on(self) -> bool:
+        value = self.bridge.metric("Valid")
+        if isinstance(value, bool):
+            return value
+        if isinstance(value, (int, float)):
+            return value != 0
+        if isinstance(value, str):
+            normalized = value.strip().lower()
+            return normalized in {"1", "true", "on", "yes"}
+        return False

custom_components/victron_mk2_mqtt/const.py

@@ -0,0 +1,48 @@
+"""Constants for the Victron MK2 MQTT integration."""
+
+from __future__ import annotations
+
+DOMAIN = "victron_mk2_mqtt"
+
+CONF_STATE_TOPIC = "state_topic"
+CONF_COMMAND_TOPIC = "command_topic"
+CONF_STATUS_TOPIC = "status_topic"
+CONF_TOPIC_ROOT = "topic_root"
+CONF_NAME = "name"
+CONF_VENUS_PORTAL_ID = "venus_portal_id"
+CONF_VENUS_TOPIC_PREFIX = "venus_topic_prefix"
+CONF_VENUS_GUIDE_COMPAT = "venus_guide_compat"
+
+DEFAULT_STATE_TOPIC = "invertergui/updates"
+DEFAULT_COMMAND_TOPIC = "invertergui/settings/set"
+DEFAULT_STATUS_TOPIC = "invertergui/settings/status"
+DEFAULT_TOPIC_ROOT = "invertergui"
+DEFAULT_NAME = "Victron Inverter"
+DEFAULT_VENUS_PORTAL_ID = "invertergui"
+DEFAULT_VENUS_TOPIC_PREFIX = ""
+DEFAULT_VENUS_GUIDE_COMPAT = True
+
+PLATFORMS = ("sensor", "binary_sensor", "select", "number", "switch")
+
+DATA_BRIDGE = "bridge"
+
+ATTR_MODE = "mode"
+ATTR_CURRENT_LIMIT = "current_limit"
+ATTR_ESS_SETPOINT = "ess_setpoint"
+ATTR_ESS_MAX_CHARGE_POWER = "ess_max_charge_power"
+ATTR_ESS_MAX_DISCHARGE_POWER = "ess_max_discharge_power"
+ATTR_ESS_MODE = "ess_mode"
+
+SERVICE_SET_REMOTE_PANEL_STATE = "set_remote_panel_state"
+SERVICE_SET_ESS_CONTROL = "set_ess_control"
+
+PANEL_MODE_CHARGER_ONLY = "charger_only"
+PANEL_MODE_INVERTER_ONLY = "inverter_only"
+PANEL_MODE_ON = "on"
+PANEL_MODE_OFF = "off"
+PANEL_MODES = (
+    PANEL_MODE_CHARGER_ONLY,
+    PANEL_MODE_INVERTER_ONLY,
+    PANEL_MODE_ON,
+    PANEL_MODE_OFF,
+)

custom_components/victron_mk2_mqtt/coordinator.py

@@ -0,0 +1,333 @@
+"""MQTT bridge for Victron MK2 integration."""
+
+from __future__ import annotations
+
+import json
+import logging
+from collections.abc import Callable
+from typing import Any
+
+from homeassistant.components import mqtt
+from homeassistant.core import HomeAssistant, callback
+from homeassistant.exceptions import HomeAssistantError
+from homeassistant.helpers.device_registry import DeviceInfo
+
+from .const import (
+    CONF_COMMAND_TOPIC,
+    CONF_NAME,
+    CONF_STATE_TOPIC,
+    CONF_STATUS_TOPIC,
+    CONF_TOPIC_ROOT,
+    CONF_VENUS_GUIDE_COMPAT,
+    CONF_VENUS_PORTAL_ID,
+    CONF_VENUS_TOPIC_PREFIX,
+    DOMAIN,
+    PANEL_MODES,
+)
+
+_LOGGER = logging.getLogger(__name__)
+
+
+class VictronMqttBridge:
+    """Maintain MQTT state and command publishing for Victron entities."""
+
+    def __init__(self, hass: HomeAssistant, config: dict[str, Any]) -> None:
+        self.hass = hass
+
+        self.name: str = config[CONF_NAME]
+        self.state_topic: str = config[CONF_STATE_TOPIC]
+        self.command_topic: str = config[CONF_COMMAND_TOPIC]
+        self.status_topic: str = config[CONF_STATUS_TOPIC]
+        self.topic_root: str = config[CONF_TOPIC_ROOT]
+        self.venus_portal_id: str = config[CONF_VENUS_PORTAL_ID]
+        self.venus_topic_prefix: str = config[CONF_VENUS_TOPIC_PREFIX]
+        self.venus_guide_compat: bool = bool(config[CONF_VENUS_GUIDE_COMPAT])
+
+        self.panel_mode_state_topic = f"{self.topic_root}/homeassistant/remote_panel_mode/state"
+        self.current_limit_state_topic = (
+            f"{self.topic_root}/homeassistant/remote_panel_current_limit/state"
+        )
+        self.standby_state_topic = f"{self.topic_root}/homeassistant/remote_panel_standby/state"
+
+        self.telemetry: dict[str, Any] = {}
+        self.panel_mode: str | None = None
+        self.current_limit: float | None = None
+        self.standby: bool | None = None
+        self.last_error: str | None = None
+        self.ess_setpoint: float | None = None
+        self.ess_max_charge_power: float | None = None
+        self.ess_max_discharge_power: float | None = None
+        self.ess_mode: int | None = None
+
+        self._listeners: set[Callable[[], None]] = set()
+        self._unsubscribers: list[Callable[[], None]] = []
+
+        venus_base = f"N/{self.venus_portal_id}/settings/0/Settings/CGwacs"
+        prefix = self.venus_topic_prefix.strip().strip("/")
+        if prefix:
+            venus_base = f"{prefix}/{venus_base}"
+        self.ess_setpoint_state_topic = f"{venus_base}/AcPowerSetPoint"
+        self.ess_max_charge_state_topic = f"{venus_base}/MaxChargePower"
+        self.ess_max_discharge_state_topic = f"{venus_base}/MaxDischargePower"
+        self.ess_mode_state_topic = f"{venus_base}/BatteryLife/State"
+
+    @property
+    def device_info(self) -> DeviceInfo:
+        """Return shared Home Assistant device metadata."""
+        return DeviceInfo(
+            identifiers={(DOMAIN, self.topic_root)},
+            name=self.name,
+            manufacturer="Victron Energy",
+            model="VE.Bus via invertergui MQTT",
+        )
+
+    async def async_setup(self) -> None:
+        """Subscribe to required MQTT topics."""
+        _LOGGER.info(
+            "Subscribing Victron MQTT bridge topics state=%s command=%s status=%s",
+            self.state_topic,
+            self.command_topic,
+            self.status_topic,
+        )
+        self._unsubscribers.append(
+            await mqtt.async_subscribe(
+                self.hass, self.state_topic, self._handle_state_message, qos=1
+            )
+        )
+        self._unsubscribers.append(
+            await mqtt.async_subscribe(
+                self.hass,
+                self.panel_mode_state_topic,
+                self._handle_panel_mode_message,
+                qos=1,
+            )
+        )
+        self._unsubscribers.append(
+            await mqtt.async_subscribe(
+                self.hass,
+                self.current_limit_state_topic,
+                self._handle_current_limit_message,
+                qos=1,
+            )
+        )
+        self._unsubscribers.append(
+            await mqtt.async_subscribe(
+                self.hass, self.standby_state_topic, self._handle_standby_message, qos=1
+            )
+        )
+        if self.venus_guide_compat:
+            self._unsubscribers.append(
+                await mqtt.async_subscribe(
+                    self.hass,
+                    self.ess_setpoint_state_topic,
+                    self._handle_ess_setpoint_message,
+                    qos=1,
+                )
+            )
+            self._unsubscribers.append(
+                await mqtt.async_subscribe(
+                    self.hass,
+                    self.ess_max_charge_state_topic,
+                    self._handle_ess_max_charge_message,
+                    qos=1,
+                )
+            )
+            self._unsubscribers.append(
+                await mqtt.async_subscribe(
+                    self.hass,
+                    self.ess_max_discharge_state_topic,
+                    self._handle_ess_max_discharge_message,
+                    qos=1,
+                )
+            )
+            self._unsubscribers.append(
+                await mqtt.async_subscribe(
+                    self.hass,
+                    self.ess_mode_state_topic,
+                    self._handle_ess_mode_message,
+                    qos=1,
+                )
+            )
+        if self.status_topic:
+            self._unsubscribers.append(
+                await mqtt.async_subscribe(
+                    self.hass, self.status_topic, self._handle_status_message, qos=1
+                )
+            )
+
+    async def async_shutdown(self) -> None:
+        """Unsubscribe all MQTT subscriptions."""
+        while self._unsubscribers:
+            unsub = self._unsubscribers.pop()
+            unsub()
+
+    @callback
+    def async_add_listener(self, listener: Callable[[], None]) -> Callable[[], None]:
+        """Register a state listener."""
+        self._listeners.add(listener)
+
+        def remove() -> None:
+            self._listeners.discard(listener)
+
+        return remove
+
+    @callback
+    def _notify_listeners(self) -> None:
+        """Notify all entities that state changed."""
+        for listener in tuple(self._listeners):
+            listener()
+
+    @staticmethod
+    def _payload_text(payload: Any) -> str:
+        if isinstance(payload, bytes):
+            return payload.decode("utf-8", errors="ignore")
+        if isinstance(payload, str):
+            return payload
+        return str(payload)
+
+    @callback
+    def _handle_state_message(self, msg: Any) -> None:
+        raw_payload = self._payload_text(msg.payload)
+        try:
+            payload = json.loads(raw_payload)
+        except json.JSONDecodeError as err:
+            _LOGGER.warning("Ignoring invalid state JSON from %s: %s", msg.topic, err)
+            return
+
+        if not isinstance(payload, dict):
+            _LOGGER.warning("Ignoring state payload from %s: expected object", msg.topic)
+            return
+
+        self.telemetry = payload
+        self._notify_listeners()
+
+    @callback
+    def _handle_panel_mode_message(self, msg: Any) -> None:
+        mode = self._payload_text(msg.payload).strip().lower()
+        if mode not in PANEL_MODES:
+            _LOGGER.debug("Ignoring unknown panel mode payload %r", msg.payload)
+            return
+
+        self.panel_mode = mode
+        self._notify_listeners()
+
+    @callback
+    def _handle_current_limit_message(self, msg: Any) -> None:
+        payload = self._payload_text(msg.payload).strip()
+        if not payload:
+            self.current_limit = None
+            self._notify_listeners()
+            return
+        try:
+            self.current_limit = float(payload)
+        except ValueError:
+            _LOGGER.debug("Ignoring invalid current limit payload %r", msg.payload)
+            return
+
+        self._notify_listeners()
+
+    @callback
+    def _handle_standby_message(self, msg: Any) -> None:
+        value = self._payload_text(msg.payload).strip().lower()
+        if value in {"on", "1", "true"}:
+            self.standby = True
+        elif value in {"off", "0", "false"}:
+            self.standby = False
+        else:
+            _LOGGER.debug("Ignoring invalid standby payload %r", msg.payload)
+            return
+
+        self._notify_listeners()
+
+    @callback
+    def _handle_status_message(self, msg: Any) -> None:
+        raw_payload = self._payload_text(msg.payload)
+        try:
+            payload = json.loads(raw_payload)
+        except json.JSONDecodeError:
+            return
+        if not isinstance(payload, dict):
+            return
+
+        if payload.get("status") == "error":
+            err = payload.get("error")
+            self.last_error = str(err) if err is not None else "unknown error"
+        else:
+            self.last_error = None
+        self._notify_listeners()
+
+    @callback
+    def _handle_ess_setpoint_message(self, msg: Any) -> None:
+        value = self._decode_venus_numeric(msg.payload)
+        if value is None:
+            return
+        self.ess_setpoint = value
+        self._notify_listeners()
+
+    @callback
+    def _handle_ess_max_charge_message(self, msg: Any) -> None:
+        value = self._decode_venus_numeric(msg.payload)
+        if value is None:
+            return
+        self.ess_max_charge_power = value
+        self._notify_listeners()
+
+    @callback
+    def _handle_ess_max_discharge_message(self, msg: Any) -> None:
+        value = self._decode_venus_numeric(msg.payload)
+        if value is None:
+            return
+        self.ess_max_discharge_power = value
+        self._notify_listeners()
+
+    @callback
+    def _handle_ess_mode_message(self, msg: Any) -> None:
+        value = self._decode_venus_numeric(msg.payload)
+        if value is None:
+            return
+        self.ess_mode = int(value)
+        self._notify_listeners()
+
+    def _decode_venus_numeric(self, payload: Any) -> float | None:
+        raw_payload = self._payload_text(payload)
+        try:
+            data = json.loads(raw_payload)
+        except json.JSONDecodeError:
+            _LOGGER.debug("Ignoring invalid Venus payload %r", raw_payload)
+            return None
+
+        value = data.get("value") if isinstance(data, dict) else None
+        if value is None:
+            return None
+        try:
+            return float(value)
+        except (TypeError, ValueError):
+            _LOGGER.debug("Ignoring non-numeric Venus payload value %r", value)
+            return None
+
+    async def async_publish_command(self, payload: dict[str, Any]) -> None:
+        """Publish a control command payload to invertergui command topic."""
+        if not self.command_topic:
+            raise HomeAssistantError("MQTT command topic is not configured")
+
+        mqtt.async_publish(
+            self.hass,
+            self.command_topic,
+            json.dumps(payload, separators=(",", ":")),
+            qos=1,
+            retain=False,
+        )
+
+    def metric(self, key: str) -> Any:
+        """Read a telemetry key."""
+        return self.telemetry.get(key)
+
+    def metric_float(self, key: str) -> float | None:
+        """Read and coerce telemetry value to float."""
+        value = self.metric(key)
+        if value is None:
+            return None
+        try:
+            return float(value)
+        except (TypeError, ValueError):
+            return None

custom_components/victron_mk2_mqtt/entity.py

@@ -0,0 +1,29 @@
+"""Shared entity base for Victron MK2 MQTT."""
+
+from __future__ import annotations
+
+from homeassistant.helpers.entity import Entity
+
+from .coordinator import VictronMqttBridge
+
+
+class VictronMqttEntity(Entity):
+    """Base entity bound to shared MQTT bridge."""
+
+    _attr_should_poll = False
+    _attr_has_entity_name = True
+
+    def __init__(self, bridge: VictronMqttBridge) -> None:
+        self.bridge = bridge
+
+    @property
+    def device_info(self):
+        """Return the shared device info."""
+        return self.bridge.device_info
+
+    async def async_added_to_hass(self) -> None:
+        """Register for coordinator updates."""
+        self.async_on_remove(self.bridge.async_add_listener(self._handle_bridge_update))
+
+    def _handle_bridge_update(self) -> None:
+        self.async_write_ha_state()

custom_components/victron_mk2_mqtt/manifest.json

@@ -0,0 +1,14 @@
+{
+  "domain": "victron_mk2_mqtt",
+  "name": "Victron MK2 MQTT",
+  "version": "0.1.0",
+  "documentation": "https://git.coadcorp.com/nathan/invertergui",
+  "issue_tracker": "https://git.coadcorp.com/nathan/invertergui/issues",
+  "dependencies": [
+    "mqtt"
+  ],
+  "codeowners": [
+    "@nathan"
+  ],
+  "iot_class": "local_push"
+}

custom_components/victron_mk2_mqtt/number.py

@@ -0,0 +1,135 @@
+"""Number entities for Victron MK2 MQTT integration."""
+
+from __future__ import annotations
+
+from typing import Any
+
+from homeassistant.components.number import NumberDeviceClass, NumberEntity, NumberMode
+from homeassistant.const import UnitOfElectricCurrent
+from homeassistant.core import HomeAssistant
+
+from .const import DATA_BRIDGE, DOMAIN
+from .coordinator import VictronMqttBridge
+from .entity import VictronMqttEntity
+
+
+async def async_setup_platform(
+    hass: HomeAssistant,
+    config: dict[str, Any],
+    async_add_entities,
+    discovery_info: dict[str, Any] | None = None,
+) -> None:
+    """Set up Victron number entities."""
+    bridge: VictronMqttBridge = hass.data[DOMAIN][DATA_BRIDGE]
+    entities: list[NumberEntity] = [VictronRemotePanelCurrentLimitNumber(bridge)]
+    if bridge.venus_guide_compat:
+        entities.extend(
+            [
+                VictronESSGridSetpointNumber(bridge),
+                VictronESSMaxChargePowerNumber(bridge),
+                VictronESSMaxDischargePowerNumber(bridge),
+            ]
+        )
+    async_add_entities(entities)
+
+
+class VictronRemotePanelCurrentLimitNumber(VictronMqttEntity, NumberEntity):
+    """Remote panel AC input current limit."""
+
+    _attr_name = "Remote Panel Current Limit"
+    _attr_icon = "mdi:current-ac"
+    _attr_native_min_value = 0.0
+    _attr_native_max_value = 100.0
+    _attr_native_step = 0.1
+    _attr_mode = NumberMode.BOX
+    _attr_device_class = NumberDeviceClass.CURRENT
+    _attr_native_unit_of_measurement = UnitOfElectricCurrent.AMPERE
+
+    def __init__(self, bridge: VictronMqttBridge) -> None:
+        super().__init__(bridge)
+        self._attr_unique_id = f"{bridge.topic_root}_remote_panel_current_limit"
+
+    @property
+    def native_value(self) -> float | None:
+        return self.bridge.current_limit
+
+    @property
+    def available(self) -> bool:
+        return bool(self.bridge.command_topic)
+
+    async def async_set_native_value(self, value: float) -> None:
+        await self.bridge.async_publish_command(
+            {"kind": "panel_state", "current_limit": float(value)}
+        )
+
+
+class _VictronESSNumberBase(VictronMqttEntity, NumberEntity):
+    """Base class for ESS compatibility numbers."""
+
+    _attr_mode = NumberMode.BOX
+    _attr_native_step = 1.0
+    _attr_native_min_value = -20000.0
+    _attr_native_max_value = 20000.0
+    _attr_native_unit_of_measurement = "W"
+    _attr_icon = "mdi:transmission-tower-export"
+
+    @property
+    def available(self) -> bool:
+        return bool(self.bridge.command_topic and self.bridge.venus_guide_compat)
+
+
+class VictronESSGridSetpointNumber(_VictronESSNumberBase):
+    """Guide-compatible ESS AC power setpoint."""
+
+    _attr_name = "ESS Grid Setpoint"
+
+    def __init__(self, bridge: VictronMqttBridge) -> None:
+        super().__init__(bridge)
+        self._attr_unique_id = f"{bridge.topic_root}_ess_grid_setpoint"
+
+    @property
+    def native_value(self) -> float | None:
+        return self.bridge.ess_setpoint
+
+    async def async_set_native_value(self, value: float) -> None:
+        await self.bridge.async_publish_command({"kind": "ess_setpoint", "value": float(value)})
+
+
+class VictronESSMaxChargePowerNumber(_VictronESSNumberBase):
+    """Guide-compatible ESS max charge power."""
+
+    _attr_name = "ESS Max Charge Power"
+    _attr_native_min_value = 0.0
+
+    def __init__(self, bridge: VictronMqttBridge) -> None:
+        super().__init__(bridge)
+        self._attr_unique_id = f"{bridge.topic_root}_ess_max_charge_power"
+
+    @property
+    def native_value(self) -> float | None:
+        return self.bridge.ess_max_charge_power
+
+    async def async_set_native_value(self, value: float) -> None:
+        await self.bridge.async_publish_command(
+            {"kind": "ess_max_charge_power", "value": float(value)}
+        )
+
+
+class VictronESSMaxDischargePowerNumber(_VictronESSNumberBase):
+    """Guide-compatible ESS max discharge power."""
+
+    _attr_name = "ESS Max Discharge Power"
+    _attr_native_min_value = 0.0
+
+    def __init__(self, bridge: VictronMqttBridge) -> None:
+        super().__init__(bridge)
+        self._attr_unique_id = f"{bridge.topic_root}_ess_max_discharge_power"
+
+    @property
+    def native_value(self) -> float | None:
+        return self.bridge.ess_max_discharge_power
+
+    async def async_set_native_value(self, value: float) -> None:
+        await self.bridge.async_publish_command(
+            {"kind": "ess_max_discharge_power", "value": float(value)}
+        )

custom_components/victron_mk2_mqtt/select.py

@@ -0,0 +1,46 @@
+"""Select entities for Victron MK2 MQTT integration."""
+
+from __future__ import annotations
+
+from typing import Any
+
+from homeassistant.components.select import SelectEntity
+from homeassistant.core import HomeAssistant
+
+from .const import DATA_BRIDGE, DOMAIN, PANEL_MODES
+from .coordinator import VictronMqttBridge
+from .entity import VictronMqttEntity
+
+
+async def async_setup_platform(
+    hass: HomeAssistant,
+    config: dict[str, Any],
+    async_add_entities,
+    discovery_info: dict[str, Any] | None = None,
+) -> None:
+    """Set up Victron select entities."""
+    bridge: VictronMqttBridge = hass.data[DOMAIN][DATA_BRIDGE]
+    async_add_entities([VictronRemotePanelModeSelect(bridge)])
+
+
+class VictronRemotePanelModeSelect(VictronMqttEntity, SelectEntity):
+    """Remote panel mode select."""
+
+    _attr_name = "Remote Panel Mode"
+    _attr_options = list(PANEL_MODES)
+    _attr_icon = "mdi:transmission-tower-export"
+
+    def __init__(self, bridge: VictronMqttBridge) -> None:
+        super().__init__(bridge)
+        self._attr_unique_id = f"{bridge.topic_root}_remote_panel_mode"
+
+    @property
+    def current_option(self) -> str | None:
+        return self.bridge.panel_mode
+
+    @property
+    def available(self) -> bool:
+        return bool(self.bridge.command_topic)
+
+    async def async_select_option(self, option: str) -> None:
+        await self.bridge.async_publish_command({"kind": "panel_state", "switch": option})

custom_components/victron_mk2_mqtt/sensor.py

@@ -0,0 +1,148 @@
+"""Sensor entities for Victron MK2 MQTT integration."""
+
+from __future__ import annotations
+
+from collections.abc import Callable
+from dataclasses import dataclass
+from typing import Any
+
+from homeassistant.components.sensor import SensorEntity, SensorStateClass
+from homeassistant.const import (
+    EntityCategory,
+    PERCENTAGE,
+    UnitOfElectricCurrent,
+    UnitOfElectricPotential,
+    UnitOfFrequency,
+)
+from homeassistant.core import HomeAssistant
+
+from .const import DATA_BRIDGE, DOMAIN
+from .coordinator import VictronMqttBridge
+from .entity import VictronMqttEntity
+
+
+@dataclass(frozen=True)
+class MetricDescription:
+    """Description for a telemetry-backed sensor."""
+
+    key: str
+    name: str
+    value_fn: Callable[[VictronMqttBridge], Any]
+    unit: str | None = None
+    state_class: SensorStateClass | None = SensorStateClass.MEASUREMENT
+    entity_category: EntityCategory | None = None
+
+
+METRICS: tuple[MetricDescription, ...] = (
+    MetricDescription(
+        key="battery_voltage",
+        name="Battery Voltage",
+        value_fn=lambda bridge: bridge.metric_float("BatVoltage"),
+        unit=UnitOfElectricPotential.VOLT,
+    ),
+    MetricDescription(
+        key="battery_current",
+        name="Battery Current",
+        value_fn=lambda bridge: bridge.metric_float("BatCurrent"),
+        unit=UnitOfElectricCurrent.AMPERE,
+    ),
+    MetricDescription(
+        key="battery_charge",
+        name="Battery Charge",
+        value_fn=lambda bridge: (
+            bridge.metric_float("ChargeState") * 100.0
+            if bridge.metric_float("ChargeState") is not None
+            else None
+        ),
+        unit=PERCENTAGE,
+    ),
+    MetricDescription(
+        key="input_voltage",
+        name="Input Voltage",
+        value_fn=lambda bridge: bridge.metric_float("InVoltage"),
+        unit=UnitOfElectricPotential.VOLT,
+    ),
+    MetricDescription(
+        key="input_current",
+        name="Input Current",
+        value_fn=lambda bridge: bridge.metric_float("InCurrent"),
+        unit=UnitOfElectricCurrent.AMPERE,
+    ),
+    MetricDescription(
+        key="input_frequency",
+        name="Input Frequency",
+        value_fn=lambda bridge: bridge.metric_float("InFrequency"),
+        unit=UnitOfFrequency.HERTZ,
+    ),
+    MetricDescription(
+        key="output_voltage",
+        name="Output Voltage",
+        value_fn=lambda bridge: bridge.metric_float("OutVoltage"),
+        unit=UnitOfElectricPotential.VOLT,
+    ),
+    MetricDescription(
+        key="output_current",
+        name="Output Current",
+        value_fn=lambda bridge: bridge.metric_float("OutCurrent"),
+        unit=UnitOfElectricCurrent.AMPERE,
+    ),
+    MetricDescription(
+        key="output_frequency",
+        name="Output Frequency",
+        value_fn=lambda bridge: bridge.metric_float("OutFrequency"),
+        unit=UnitOfFrequency.HERTZ,
+    ),
+    MetricDescription(
+        key="input_power",
+        name="Input Power",
+        value_fn=lambda bridge: _product(bridge.metric_float("InVoltage"), bridge.metric_float("InCurrent")),
+        unit="VA",
+    ),
+    MetricDescription(
+        key="output_power",
+        name="Output Power",
+        value_fn=lambda bridge: _product(bridge.metric_float("OutVoltage"), bridge.metric_float("OutCurrent")),
+        unit="VA",
+    ),
+    MetricDescription(
+        key="last_command_error",
+        name="Last Command Error",
+        value_fn=lambda bridge: bridge.last_error,
+        state_class=None,
+        entity_category=EntityCategory.DIAGNOSTIC,
+    ),
+)
+
+
+def _product(a: float | None, b: float | None) -> float | None:
+    if a is None or b is None:
+        return None
+    return a * b
+
+
+async def async_setup_platform(
+    hass: HomeAssistant,
+    config: dict[str, Any],
+    async_add_entities,
+    discovery_info: dict[str, Any] | None = None,
+) -> None:
+    """Set up Victron telemetry sensors."""
+    bridge: VictronMqttBridge = hass.data[DOMAIN][DATA_BRIDGE]
+    async_add_entities(VictronMetricSensor(bridge, metric) for metric in METRICS)
+
+
+class VictronMetricSensor(VictronMqttEntity, SensorEntity):
+    """Generic telemetry sensor."""
+
+    def __init__(self, bridge: VictronMqttBridge, description: MetricDescription) -> None:
+        super().__init__(bridge)
+        self.entity_description = description
+        self._attr_unique_id = f"{bridge.topic_root}_{description.key}"
+        self._attr_name = description.name
+        self._attr_native_unit_of_measurement = description.unit
+        self._attr_state_class = description.state_class
+        self._attr_entity_category = description.entity_category
+
+    @property
+    def native_value(self):
+        return self.entity_description.value_fn(self.bridge)

custom_components/victron_mk2_mqtt/services.yaml

@@ -0,0 +1,75 @@
+set_remote_panel_state:
+  name: Set Remote Panel State
+  description: Set the remote panel mode and/or AC input current limit over MQTT.
+  fields:
+    mode:
+      name: Mode
+      description: Remote panel mode.
+      required: false
+      selector:
+        select:
+          mode: dropdown
+          options:
+            - charger_only
+            - inverter_only
+            - on
+            - off
+    current_limit:
+      name: Current Limit
+      description: AC input current limit in amps.
+      required: false
+      selector:
+        number:
+          min: 0
+          max: 100
+          step: 0.1
+          unit_of_measurement: A
+          mode: box
+
+set_ess_control:
+  name: Set ESS Control
+  description: Set ESS-style control values compatible with guide CGwacs paths.
+  fields:
+    ess_setpoint:
+      name: ESS Setpoint
+      description: AC power setpoint in watts. Positive charges/imports, negative discharges/exports.
+      required: false
+      selector:
+        number:
+          min: -20000
+          max: 20000
+          step: 1
+          unit_of_measurement: W
+          mode: box
+    ess_max_charge_power:
+      name: ESS Max Charge Power
+      description: Maximum allowed charge/import power in watts.
+      required: false
+      selector:
+        number:
+          min: 0
+          max: 20000
+          step: 1
+          unit_of_measurement: W
+          mode: box
+    ess_max_discharge_power:
+      name: ESS Max Discharge Power
+      description: Maximum allowed discharge/export power in watts.
+      required: false
+      selector:
+        number:
+          min: 0
+          max: 20000
+          step: 1
+          unit_of_measurement: W
+          mode: box
+    ess_mode:
+      name: ESS Mode
+      description: ESS battery life mode value (10 optimized, 9 keep charged).
+      required: false
+      selector:
+        number:
+          min: 9
+          max: 10
+          step: 1
+          mode: box

custom_components/victron_mk2_mqtt/switch.py

@@ -0,0 +1,76 @@
+"""Switch entities for Victron MK2 MQTT integration."""
+
+from __future__ import annotations
+
+from typing import Any
+
+from homeassistant.components.switch import SwitchEntity
+from homeassistant.core import HomeAssistant
+
+from .const import DATA_BRIDGE, DOMAIN
+from .coordinator import VictronMqttBridge
+from .entity import VictronMqttEntity
+
+
+async def async_setup_platform(
+    hass: HomeAssistant,
+    config: dict[str, Any],
+    async_add_entities,
+    discovery_info: dict[str, Any] | None = None,
+) -> None:
+    """Set up Victron switch entities."""
+    bridge: VictronMqttBridge = hass.data[DOMAIN][DATA_BRIDGE]
+    entities: list[SwitchEntity] = [VictronRemotePanelStandbySwitch(bridge)]
+    if bridge.venus_guide_compat:
+        entities.append(VictronESSOptimizedModeSwitch(bridge))
+    async_add_entities(entities)
+
+
+class VictronRemotePanelStandbySwitch(VictronMqttEntity, SwitchEntity):
+    """Remote panel standby switch."""
+
+    _attr_name = "Remote Panel Standby"
+    _attr_icon = "mdi:power-sleep"
+
+    def __init__(self, bridge: VictronMqttBridge) -> None:
+        super().__init__(bridge)
+        self._attr_unique_id = f"{bridge.topic_root}_remote_panel_standby"
+
+    @property
+    def is_on(self) -> bool:
+        return bool(self.bridge.standby)
+
+    @property
+    def available(self) -> bool:
+        return bool(self.bridge.command_topic)
+
+    async def async_turn_on(self, **kwargs: Any) -> None:
+        await self.bridge.async_publish_command({"kind": "standby", "standby": True})
+
+    async def async_turn_off(self, **kwargs: Any) -> None:
+        await self.bridge.async_publish_command({"kind": "standby", "standby": False})
+
+
+class VictronESSOptimizedModeSwitch(VictronMqttEntity, SwitchEntity):
+    """Guide-compatible ESS optimized mode switch."""
+
+    _attr_name = "ESS Optimized Mode"
+    _attr_icon = "mdi:battery-sync"
+
+    def __init__(self, bridge: VictronMqttBridge) -> None:
+        super().__init__(bridge)
+        self._attr_unique_id = f"{bridge.topic_root}_ess_optimized_mode"
+
+    @property
+    def is_on(self) -> bool:
+        return self.bridge.ess_mode == 10
+
+    @property
+    def available(self) -> bool:
+        return bool(self.bridge.command_topic and self.bridge.venus_guide_compat)
+
+    async def async_turn_on(self, **kwargs: Any) -> None:
+        await self.bridge.async_publish_command({"kind": "ess_mode", "value": 10})
+
+    async def async_turn_off(self, **kwargs: Any) -> None:
+        await self.bridge.async_publish_command({"kind": "ess_mode", "value": 9})

go.mod

@@ -1,10 +1,32 @@
-module github.com/diebietse/invertergui
+module git.coadcorp.com/nathan/invertergui
+
+go 1.26
 
 require (
-	github.com/gorilla/websocket v1.4.0
-	github.com/prometheus/client_golang v0.9.2
-	github.com/rakyll/statik v0.1.5
-	github.com/stretchr/testify v1.3.0
+	github.com/eclipse/paho.mqtt.golang v1.5.1
+	github.com/gorilla/websocket v1.5.3
+	github.com/jessevdk/go-flags v1.6.1
+	github.com/prometheus/client_golang v1.23.2
+	github.com/sirupsen/logrus v1.9.4
+	github.com/stretchr/testify v1.11.1
 	github.com/tarm/serial v0.0.0-20180830185346-98f6abe2eb07
-	golang.org/x/sys v0.0.0-20190312061237-fead79001313 // indirect
+)
+
+require (
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cespare/xxhash/v2 v2.3.0 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/kr/text v0.2.0 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/prometheus/client_model v0.6.2 // indirect
+	github.com/prometheus/common v0.67.5 // indirect
+	github.com/prometheus/procfs v0.19.2 // indirect
+	github.com/rogpeppe/go-internal v1.14.1 // indirect
+	go.yaml.in/yaml/v2 v2.4.3 // indirect
+	golang.org/x/net v0.50.0 // indirect
+	golang.org/x/sync v0.19.0 // indirect
+	golang.org/x/sys v0.41.0 // indirect
+	google.golang.org/protobuf v1.36.11 // indirect
+	gopkg.in/yaml.v3 v3.0.1 // indirect
 )

go.sum

@@ -1,32 +1,60 @@
-github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973 h1:xJ4a3vCFaGF/jqvzLMYoU8P317H5OQ+Via4RmuPwCS0=
-github.com/beorn7/perks v0.0.0-20180321164747-3a771d992973/go.mod h1:Dwedo/Wpr24TaqPxmxbtue+5NUziq4I4S80YR8gNf3Q=
-github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
-github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
-github.com/golang/protobuf v1.2.0 h1:P3YflyNX/ehuJFLhxviNdFxQPkGK5cDcApsge1SqnvM=
-github.com/golang/protobuf v1.2.0/go.mod h1:6lQm79b+lXiMfvg/cZm0SGofjICqVBUtrP5yJMmIC1U=
-github.com/gorilla/websocket v1.4.0 h1:WDFjx/TMzVgy9VdMMQi2K2Emtwi2QcUQsztZ/zLaH/Q=
-github.com/gorilla/websocket v1.4.0/go.mod h1:E7qHFY5m1UJ88s3WnNqhKjPHQ0heANvMoAMk2YaljkQ=
-github.com/matttproud/golang_protobuf_extensions v1.0.1 h1:4hp9jkHxhMHkqkrB3Ix0jegS5sx/RkqARlsWZ6pIwiU=
-github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
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+github.com/beorn7/perks v1.0.1/go.mod h1:G2ZrVWU2WbWT9wwq4/hrbKbnv/1ERSJQ0ibhJ6rlkpw=
+github.com/cespare/xxhash/v2 v2.3.0 h1:UL815xU9SqsFlibzuggzjXhog7bL6oX9BbNZnL2UFvs=
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+github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
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-github.com/prometheus/common v0.0.0-20181126121408-4724e9255275 h1:PnBWHBf+6L0jOqq0gIVUe6Yk0/QMZ640k6NvkxcBf+8=
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homeassistant/dashboards/invertergui_mqtt_dashboard.yaml

@@ -0,0 +1,132 @@
+title: Victron Inverter MQTT
+views:
+  - title: Inverter
+    path: victron-inverter
+    icon: mdi:flash
+    badges:
+      - entity: binary_sensor.victron_online
+      - entity: binary_sensor.victron_data_valid
+      - entity: sensor.victron_last_command_status
+    cards:
+      - type: vertical-stack
+        cards:
+          - type: markdown
+            content: |
+              ## Remote Panel Control
+              Mode and current limit are published together over MQTT, matching `set_remote_panel_state`.
+          - type: entities
+            title: Current Remote State
+            state_color: true
+            show_header_toggle: false
+            entities:
+              - entity: select.victron_remote_panel_mode
+                name: Mode
+              - entity: number.victron_remote_panel_current_limit
+                name: AC Input Current Limit
+              - entity: switch.victron_remote_panel_standby
+                name: Prevent Sleep While Off
+              - entity: sensor.victron_last_command_error
+                name: Last Command Error
+          - type: entities
+            title: Apply Mode + Current Limit
+            show_header_toggle: false
+            entities:
+              - entity: input_select.victron_remote_panel_mode_target
+                name: Target Mode
+              - entity: input_number.victron_remote_panel_current_limit_target
+                name: Target Current Limit
+              - entity: script.victron_mqtt_set_remote_panel_state
+                name: Apply Mode + Current Limit
+          - type: entities
+            title: Apply Standby
+            show_header_toggle: false
+            entities:
+              - entity: input_boolean.victron_remote_panel_standby_target
+                name: Target Standby
+              - entity: script.victron_mqtt_set_remote_panel_standby
+                name: Apply Standby
+          - type: entities
+            title: ESS Guide-Style Control (MQTT)
+            show_header_toggle: false
+            entities:
+              - entity: number.victron_ess_grid_setpoint
+                name: Grid Setpoint (W)
+              - entity: number.victron_ess_max_charge_power
+                name: Max Charge Power (W)
+              - entity: number.victron_ess_max_discharge_power
+                name: Max Discharge Power (W)
+              - entity: switch.victron_ess_optimized_mode
+                name: Optimized Mode (10 on / 9 off)
+
+      - type: grid
+        columns: 3
+        square: false
+        cards:
+          - type: entities
+            title: Output
+            show_header_toggle: false
+            entities:
+              - entity: sensor.victron_output_current
+                name: Output Current
+              - entity: sensor.victron_output_voltage
+                name: Output Voltage
+              - entity: sensor.victron_output_frequency
+                name: Output Frequency
+              - entity: sensor.victron_output_power
+                name: Output Power
+          - type: entities
+            title: Input
+            show_header_toggle: false
+            entities:
+              - entity: sensor.victron_input_current
+                name: Input Current
+              - entity: sensor.victron_input_voltage
+                name: Input Voltage
+              - entity: sensor.victron_input_frequency
+                name: Input Frequency
+              - entity: sensor.victron_input_power
+                name: Input Power
+              - entity: sensor.victron_input_minus_output_power
+                name: Input - Output Power
+          - type: entities
+            title: Battery
+            show_header_toggle: false
+            entities:
+              - entity: sensor.victron_battery_current
+                name: Battery Current
+              - entity: sensor.victron_battery_voltage
+                name: Battery Voltage
+              - entity: sensor.victron_battery_power
+                name: Battery Power
+              - entity: sensor.victron_battery_charge
+                name: Battery Charge
+
+      - type: entities
+        title: LED Status
+        show_header_toggle: false
+        entities:
+          - entity: sensor.victron_led_mains
+            name: Mains
+          - entity: sensor.victron_led_absorb
+            name: Absorb
+          - entity: sensor.victron_led_bulk
+            name: Bulk
+          - entity: sensor.victron_led_float
+            name: Float
+          - entity: sensor.victron_led_inverter
+            name: Inverter
+          - entity: sensor.victron_led_overload
+            name: Overload
+          - entity: sensor.victron_led_low_battery
+            name: Low Battery
+          - entity: sensor.victron_led_over_temp
+            name: Over Temperature
+
+      - type: history-graph
+        title: Power (Last 2 Hours)
+        hours_to_show: 2
+        refresh_interval: 60
+        entities:
+          - entity: sensor.victron_input_power
+          - entity: sensor.victron_output_power
+          - entity: sensor.victron_battery_power

homeassistant/packages/invertergui_mqtt.yaml

@@ -0,0 +1,401 @@
+# MQTT-only Home Assistant package for invertergui.
+# This avoids duplicate entities from MQTT auto-discovery/custom integration.
+#
+# Requirements:
+# - invertergui started with MQTT publishing enabled.
+# - invertergui MQTT discovery disabled (`--mqtt.ha.enabled=false`) when using this package.
+# - for guide-style ESS controls below, enable:
+#   `MQTT_VENUS_ENABLED=true`
+#   `MQTT_VENUS_GUIDE_COMPAT=true`
+#   `MQTT_VENUS_TOPIC_PREFIX=victron`
+#   `MQTT_VENUS_PORTAL_ID=invertergui`
+
+mqtt:
+  sensor:
+    - name: Victron Battery Voltage
+      unique_id: invertergui_mqtt_battery_voltage
+      state_topic: invertergui/updates
+      value_template: "{{ value_json.BatVoltage }}"
+      unit_of_measurement: V
+      device_class: voltage
+      state_class: measurement
+    - name: Victron Battery Current
+      unique_id: invertergui_mqtt_battery_current
+      state_topic: invertergui/updates
+      value_template: "{{ value_json.BatCurrent }}"
+      unit_of_measurement: A
+      device_class: current
+      state_class: measurement
+    - name: Victron Battery Charge
+      unique_id: invertergui_mqtt_battery_charge
+      state_topic: invertergui/updates
+      value_template: "{{ ((value_json.ChargeState | float(0)) * 100) | round(1) }}"
+      unit_of_measurement: "%"
+      device_class: battery
+      state_class: measurement
+    - name: Victron Input Voltage
+      unique_id: invertergui_mqtt_input_voltage
+      state_topic: invertergui/updates
+      value_template: "{{ value_json.InVoltage }}"
+      unit_of_measurement: V
+      device_class: voltage
+      state_class: measurement
+    - name: Victron Input Current
+      unique_id: invertergui_mqtt_input_current
+      state_topic: invertergui/updates
+      value_template: "{{ value_json.InCurrent }}"
+      unit_of_measurement: A
+      device_class: current
+      state_class: measurement
+    - name: Victron Input Frequency
+      unique_id: invertergui_mqtt_input_frequency
+      state_topic: invertergui/updates
+      value_template: "{{ value_json.InFrequency }}"
+      unit_of_measurement: Hz
+      device_class: frequency
+      state_class: measurement
+    - name: Victron Output Voltage
+      unique_id: invertergui_mqtt_output_voltage
+      state_topic: invertergui/updates
+      value_template: "{{ value_json.OutVoltage }}"
+      unit_of_measurement: V
+      device_class: voltage
+      state_class: measurement
+    - name: Victron Output Current
+      unique_id: invertergui_mqtt_output_current
+      state_topic: invertergui/updates
+      value_template: "{{ value_json.OutCurrent }}"
+      unit_of_measurement: A
+      device_class: current
+      state_class: measurement
+    - name: Victron Output Frequency
+      unique_id: invertergui_mqtt_output_frequency
+      state_topic: invertergui/updates
+      value_template: "{{ value_json.OutFrequency }}"
+      unit_of_measurement: Hz
+      device_class: frequency
+      state_class: measurement
+    - name: Victron Input Power
+      unique_id: invertergui_mqtt_input_power
+      state_topic: invertergui/updates
+      value_template: "{{ ((value_json.InVoltage | float(0)) * (value_json.InCurrent | float(0))) | round(1) }}"
+      unit_of_measurement: VA
+      state_class: measurement
+    - name: Victron Output Power
+      unique_id: invertergui_mqtt_output_power
+      state_topic: invertergui/updates
+      value_template: "{{ ((value_json.OutVoltage | float(0)) * (value_json.OutCurrent | float(0))) | round(1) }}"
+      unit_of_measurement: VA
+      state_class: measurement
+    - name: Victron Last Command Status
+      unique_id: invertergui_mqtt_last_command_status
+      state_topic: invertergui/settings/status
+      value_template: "{{ value_json.status | default('unknown') }}"
+      icon: mdi:message-alert-outline
+    - name: Victron Last Command Error
+      unique_id: invertergui_mqtt_last_command_error
+      state_topic: invertergui/settings/status
+      value_template: >-
+        {% if value_json.status == 'error' %}
+          {{ value_json.error | default('unknown error') }}
+        {% else %}
+          none
+        {% endif %}
+      icon: mdi:alert-circle-outline
+    - name: Victron LED Mains
+      unique_id: invertergui_mqtt_led_mains
+      state_topic: invertergui/updates
+      value_template: >-
+        {% set leds = value_json.LEDs | default({}) %}
+        {% set v = leds['0'] | default(0) | int(0) %}
+        {% if v == 1 %}on{% elif v == 2 %}blink{% else %}off{% endif %}
+      icon: mdi:transmission-tower
+    - name: Victron LED Absorb
+      unique_id: invertergui_mqtt_led_absorb
+      state_topic: invertergui/updates
+      value_template: >-
+        {% set leds = value_json.LEDs | default({}) %}
+        {% set v = leds['1'] | default(0) | int(0) %}
+        {% if v == 1 %}on{% elif v == 2 %}blink{% else %}off{% endif %}
+      icon: mdi:water-outline
+    - name: Victron LED Bulk
+      unique_id: invertergui_mqtt_led_bulk
+      state_topic: invertergui/updates
+      value_template: >-
+        {% set leds = value_json.LEDs | default({}) %}
+        {% set v = leds['2'] | default(0) | int(0) %}
+        {% if v == 1 %}on{% elif v == 2 %}blink{% else %}off{% endif %}
+      icon: mdi:battery-plus
+    - name: Victron LED Float
+      unique_id: invertergui_mqtt_led_float
+      state_topic: invertergui/updates
+      value_template: >-
+        {% set leds = value_json.LEDs | default({}) %}
+        {% set v = leds['3'] | default(0) | int(0) %}
+        {% if v == 1 %}on{% elif v == 2 %}blink{% else %}off{% endif %}
+      icon: mdi:battery-heart-variant
+    - name: Victron LED Inverter
+      unique_id: invertergui_mqtt_led_inverter
+      state_topic: invertergui/updates
+      value_template: >-
+        {% set leds = value_json.LEDs | default({}) %}
+        {% set v = leds['4'] | default(0) | int(0) %}
+        {% if v == 1 %}on{% elif v == 2 %}blink{% else %}off{% endif %}
+      icon: mdi:power-plug
+    - name: Victron LED Overload
+      unique_id: invertergui_mqtt_led_overload
+      state_topic: invertergui/updates
+      value_template: >-
+        {% set leds = value_json.LEDs | default({}) %}
+        {% set v = leds['5'] | default(0) | int(0) %}
+        {% if v == 1 %}on{% elif v == 2 %}blink{% else %}off{% endif %}
+      icon: mdi:alert-octagon
+    - name: Victron LED Low Battery
+      unique_id: invertergui_mqtt_led_low_battery
+      state_topic: invertergui/updates
+      value_template: >-
+        {% set leds = value_json.LEDs | default({}) %}
+        {% set v = leds['6'] | default(0) | int(0) %}
+        {% if v == 1 %}on{% elif v == 2 %}blink{% else %}off{% endif %}
+      icon: mdi:battery-alert-variant-outline
+    - name: Victron LED Over Temp
+      unique_id: invertergui_mqtt_led_over_temp
+      state_topic: invertergui/updates
+      value_template: >-
+        {% set leds = value_json.LEDs | default({}) %}
+        {% set v = leds['7'] | default(0) | int(0) %}
+        {% if v == 1 %}on{% elif v == 2 %}blink{% else %}off{% endif %}
+      icon: mdi:thermometer-alert
+
+  binary_sensor:
+    - name: Victron Online
+      unique_id: invertergui_mqtt_online
+      state_topic: invertergui/updates
+      value_template: "ON"
+      payload_on: "ON"
+      payload_off: "OFF"
+      expire_after: 120
+      device_class: connectivity
+    - name: Victron Data Valid
+      unique_id: invertergui_mqtt_data_valid
+      state_topic: invertergui/updates
+      value_template: "{{ value_json.Valid }}"
+      payload_on: "true"
+      payload_off: "false"
+      entity_category: diagnostic
+
+  select:
+    - name: Victron Remote Panel Mode
+      unique_id: invertergui_mqtt_remote_panel_mode
+      state_topic: invertergui/homeassistant/remote_panel_mode/state
+      command_topic: invertergui/settings/set
+      command_template: '{"kind":"panel_state","switch":"{{ value }}"}'
+      options:
+        - charger_only
+        - inverter_only
+        - on
+        - off
+      icon: mdi:transmission-tower-export
+
+  number:
+    - name: Victron Remote Panel Current Limit
+      unique_id: invertergui_mqtt_remote_panel_current_limit
+      state_topic: invertergui/homeassistant/remote_panel_current_limit/state
+      command_topic: invertergui/settings/set
+      command_template: '{"kind":"panel_state","current_limit":{{ value | float(0) }}}'
+      unit_of_measurement: A
+      device_class: current
+      mode: box
+      min: 0
+      max: 100
+      step: 0.1
+      icon: mdi:current-ac
+    - name: Victron ESS Grid Setpoint
+      unique_id: invertergui_mqtt_ess_grid_setpoint
+      state_topic: victron/N/invertergui/settings/0/Settings/CGwacs/AcPowerSetPoint
+      value_template: "{{ value_json.value | float(0) }}"
+      command_topic: victron/W/invertergui/settings/0/Settings/CGwacs/AcPowerSetPoint
+      command_template: '{"value":{{ value | float(0) | round(0) }}}'
+      unit_of_measurement: W
+      mode: box
+      min: -20000
+      max: 20000
+      step: 1
+      icon: mdi:transmission-tower-export
+    - name: Victron ESS Max Charge Power
+      unique_id: invertergui_mqtt_ess_max_charge_power
+      state_topic: victron/N/invertergui/settings/0/Settings/CGwacs/MaxChargePower
+      value_template: "{{ value_json.value | float(0) }}"
+      command_topic: victron/W/invertergui/settings/0/Settings/CGwacs/MaxChargePower
+      command_template: '{"value":{{ value | float(0) | round(0) }}}'
+      unit_of_measurement: W
+      mode: box
+      min: 0
+      max: 20000
+      step: 1
+      icon: mdi:battery-plus
+    - name: Victron ESS Max Discharge Power
+      unique_id: invertergui_mqtt_ess_max_discharge_power
+      state_topic: victron/N/invertergui/settings/0/Settings/CGwacs/MaxDischargePower
+      value_template: "{{ value_json.value | float(0) }}"
+      command_topic: victron/W/invertergui/settings/0/Settings/CGwacs/MaxDischargePower
+      command_template: '{"value":{{ value | float(0) | round(0) }}}'
+      unit_of_measurement: W
+      mode: box
+      min: 0
+      max: 20000
+      step: 1
+      icon: mdi:battery-minus
+
+  switch:
+    - name: Victron Remote Panel Standby
+      unique_id: invertergui_mqtt_remote_panel_standby
+      state_topic: invertergui/homeassistant/remote_panel_standby/state
+      command_topic: invertergui/settings/set
+      payload_on: '{"kind":"standby","standby":true}'
+      payload_off: '{"kind":"standby","standby":false}'
+      state_on: "ON"
+      state_off: "OFF"
+      icon: mdi:power-sleep
+    - name: Victron ESS Optimized Mode
+      unique_id: invertergui_mqtt_ess_optimized_mode
+      state_topic: victron/N/invertergui/settings/0/Settings/CGwacs/BatteryLife/State
+      value_template: "{{ value_json.value | int(9) }}"
+      command_topic: victron/W/invertergui/settings/0/Settings/CGwacs/BatteryLife/State
+      payload_on: '{"value":10}'
+      payload_off: '{"value":9}'
+      state_on: "10"
+      state_off: "9"
+      icon: mdi:battery-sync
+
+input_select:
+  victron_remote_panel_mode_target:
+    name: Victron Target Mode
+    options:
+      - charger_only
+      - inverter_only
+      - on
+      - off
+    icon: mdi:transmission-tower-export
+
+input_number:
+  victron_remote_panel_current_limit_target:
+    name: Victron Target Current Limit
+    min: 0
+    max: 100
+    step: 0.1
+    unit_of_measurement: A
+    mode: box
+    icon: mdi:current-ac
+
+input_boolean:
+  victron_remote_panel_standby_target:
+    name: Victron Target Standby
+    icon: mdi:power-sleep
+
+script:
+  victron_mqtt_set_remote_panel_state:
+    alias: Victron MQTT Set Remote Panel State
+    description: Set panel mode and current limit in one MQTT command.
+    mode: single
+    icon: mdi:send
+    sequence:
+      - service: mqtt.publish
+        data:
+          topic: invertergui/settings/set
+          qos: 1
+          payload: >-
+            {"kind":"panel_state","switch":"{{ states('input_select.victron_remote_panel_mode_target') }}","current_limit":{{ states('input_number.victron_remote_panel_current_limit_target') | float(0) | round(1) }}}
+
+  victron_mqtt_set_remote_panel_standby:
+    alias: Victron MQTT Set Remote Panel Standby
+    description: Set standby state from helper input.
+    mode: single
+    icon: mdi:send-circle
+    sequence:
+      - service: mqtt.publish
+        data:
+          topic: invertergui/settings/set
+          qos: 1
+          payload: >-
+            {"kind":"standby","standby":{% if is_state('input_boolean.victron_remote_panel_standby_target', 'on') %}true{% else %}false{% endif %}}
+
+template:
+  - sensor:
+      - name: Victron Battery Power
+        unique_id: invertergui_mqtt_battery_power
+        unit_of_measurement: W
+        state_class: measurement
+        icon: mdi:battery-charging
+        state: >-
+          {{ ((states('sensor.victron_battery_voltage') | float(0)) * (states('sensor.victron_battery_current') | float(0))) | round(1) }}
+      - name: Victron Input Minus Output Power
+        unique_id: invertergui_mqtt_input_minus_output_power
+        unit_of_measurement: VA
+        state_class: measurement
+        icon: mdi:flash-triangle
+        state: >-
+          {{ (states('sensor.victron_input_power') | float(0) - states('sensor.victron_output_power') | float(0)) | round(1) }}
+
+automation:
+  - id: victron_mqtt_sync_target_mode
+    alias: Victron MQTT Sync Mode Target
+    trigger:
+      - platform: state
+        entity_id: select.victron_remote_panel_mode
+      - platform: homeassistant
+        event: start
+    condition:
+      - condition: template
+        value_template: >-
+          {{ states('select.victron_remote_panel_mode') in ['charger_only', 'inverter_only', 'on', 'off'] }}
+    action:
+      - service: input_select.select_option
+        target:
+          entity_id: input_select.victron_remote_panel_mode_target
+        data:
+          option: "{{ states('select.victron_remote_panel_mode') }}"
+
+  - id: victron_mqtt_sync_target_current_limit
+    alias: Victron MQTT Sync Current Limit Target
+    trigger:
+      - platform: state
+        entity_id: number.victron_remote_panel_current_limit
+      - platform: homeassistant
+        event: start
+    condition:
+      - condition: template
+        value_template: >-
+          {{ states('number.victron_remote_panel_current_limit') not in ['unknown', 'unavailable'] }}
+    action:
+      - service: input_number.set_value
+        target:
+          entity_id: input_number.victron_remote_panel_current_limit_target
+        data:
+          value: "{{ states('number.victron_remote_panel_current_limit') | float(0) }}"
+
+  - id: victron_mqtt_sync_target_standby
+    alias: Victron MQTT Sync Standby Target
+    trigger:
+      - platform: state
+        entity_id: switch.victron_remote_panel_standby
+      - platform: homeassistant
+        event: start
+    action:
+      - choose:
+          - conditions:
+              - condition: state
+                entity_id: switch.victron_remote_panel_standby
+                state: "on"
+            sequence:
+              - service: input_boolean.turn_on
+                target:
+                  entity_id: input_boolean.victron_remote_panel_standby_target
+          - conditions:
+              - condition: state
+                entity_id: switch.victron_remote_panel_standby
+                state: "off"
+            sequence:
+              - service: input_boolean.turn_off
+                target:
+                  entity_id: input_boolean.victron_remote_panel_standby_target

mk2core/core.go

@@ -1,9 +1,12 @@
 package mk2core
 
 import (
-	"github.com/diebietse/invertergui/mk2driver"
+	"git.coadcorp.com/nathan/invertergui/mk2driver"
+	"github.com/sirupsen/logrus"
 )
 
+var log = logrus.WithField("ctx", "inverter-gui-core")
+
 type Core struct {
 	mk2driver.Mk2
 	plugins  map[*subscription]bool
@@ -16,6 +19,7 @@ func NewCore(m mk2driver.Mk2) *Core {
 		register: make(chan *subscription, 255),
 		plugins:  map[*subscription]bool{},
 	}
+	log.Info("Core initialized")
 	go core.run()
 	return core
 }
@@ -25,6 +29,7 @@ func (c *Core) NewSubscription() mk2driver.Mk2 {
 		send: make(chan *mk2driver.Mk2Info),
 	}
 	c.register <- sub
+	log.Debug("New plugin subscription registered")
 	return sub
 }
 
@@ -33,11 +38,13 @@ func (c *Core) run() {
 		select {
 		case r := <-c.register:
 			c.plugins[r] = true
+			log.WithField("subscribers", len(c.plugins)).Debug("Subscription added")
 		case e := <-c.C():
 			for plugin := range c.plugins {
 				select {
 				case plugin.send <- e:
 				default:
+					log.WithField("subscribers", len(c.plugins)).Warn("Dropping update for a slow subscriber")
 				}
 			}
 		}

mk2driver/managed_writer.go

@@ -0,0 +1,232 @@
+package mk2driver
+
+import (
+	"errors"
+	"fmt"
+	"sort"
+	"sync"
+	"time"
+)
+
+type WriterProfile string
+
+const (
+	WriterProfileNormal      WriterProfile = "normal"
+	WriterProfileMaintenance WriterProfile = "maintenance"
+	WriterProfileReadOnly    WriterProfile = "read_only"
+)
+
+type WriterPolicy struct {
+	Profile               WriterProfile
+	MaxCurrentLimitA      *float64
+	ModeChangeMinInterval time.Duration
+	LockoutWindow         time.Duration
+	AllowedPanelStates    map[PanelSwitchState]struct{}
+}
+
+type CommandEvent struct {
+	Timestamp time.Time     `json:"timestamp"`
+	Source    CommandSource `json:"source"`
+	Kind      string        `json:"kind"`
+	Allowed   bool          `json:"allowed"`
+	Error     string        `json:"error,omitempty"`
+}
+
+type ManagedWriter struct {
+	writer SettingsWriter
+	policy WriterPolicy
+
+	mu             sync.Mutex
+	lastModeChange time.Time
+	lockoutUntil   time.Time
+	events         []CommandEvent
+}
+
+var _ SettingsWriter = (*ManagedWriter)(nil)
+var _ SourceAwareSettingsWriter = (*ManagedWriter)(nil)
+
+func NewManagedWriter(writer SettingsWriter, policy WriterPolicy) *ManagedWriter {
+	if policy.Profile == "" {
+		policy.Profile = WriterProfileNormal
+	}
+	return &ManagedWriter{
+		writer: writer,
+		policy: policy,
+		events: make([]CommandEvent, 0, 100),
+	}
+}
+
+func (m *ManagedWriter) WriteRAMVar(id uint16, value int16) error {
+	return m.WriteRAMVarWithSource(CommandSourceUnknown, id, value)
+}
+
+func (m *ManagedWriter) WriteSetting(id uint16, value int16) error {
+	return m.WriteSettingWithSource(CommandSourceUnknown, id, value)
+}
+
+func (m *ManagedWriter) SetPanelState(switchState PanelSwitchState, currentLimitA *float64) error {
+	return m.SetPanelStateWithSource(CommandSourceUnknown, switchState, currentLimitA)
+}
+
+func (m *ManagedWriter) SetStandby(enabled bool) error {
+	return m.SetStandbyWithSource(CommandSourceUnknown, enabled)
+}
+
+func (m *ManagedWriter) WriteRAMVarWithSource(source CommandSource, id uint16, value int16) error {
+	return m.apply(source, "write_ram_var", func() error {
+		if err := m.ensureProfileAllows("write_ram_var"); err != nil {
+			return err
+		}
+		return m.baseWriter().WriteRAMVar(id, value)
+	})
+}
+
+func (m *ManagedWriter) WriteSettingWithSource(source CommandSource, id uint16, value int16) error {
+	return m.apply(source, "write_setting", func() error {
+		if err := m.ensureProfileAllows("write_setting"); err != nil {
+			return err
+		}
+		return m.baseWriter().WriteSetting(id, value)
+	})
+}
+
+func (m *ManagedWriter) SetPanelStateWithSource(source CommandSource, switchState PanelSwitchState, currentLimitA *float64) error {
+	return m.apply(source, "set_panel_state", func() error {
+		if err := m.ensureProfileAllows("set_panel_state"); err != nil {
+			return err
+		}
+		if len(m.policy.AllowedPanelStates) > 0 {
+			if _, ok := m.policy.AllowedPanelStates[switchState]; !ok {
+				return fmt.Errorf(
+					"panel switch mode %s denied by allowlist policy; allowed modes: %s",
+					panelStateLabel(switchState),
+					stringsForAllowedPanelStates(m.policy.AllowedPanelStates),
+				)
+			}
+		}
+		if m.policy.MaxCurrentLimitA != nil && currentLimitA != nil && *currentLimitA > *m.policy.MaxCurrentLimitA {
+			return fmt.Errorf("current limit %.2fA exceeds configured policy max %.2fA", *currentLimitA, *m.policy.MaxCurrentLimitA)
+		}
+		if m.policy.Profile == WriterProfileMaintenance && switchState != PanelSwitchOff {
+			return errors.New("maintenance profile only allows panel switch off")
+		}
+		if m.policy.ModeChangeMinInterval > 0 && !m.lastModeChange.IsZero() && time.Since(m.lastModeChange) < m.policy.ModeChangeMinInterval {
+			return fmt.Errorf("mode change denied due to rate limit; wait %s", m.policy.ModeChangeMinInterval-time.Since(m.lastModeChange))
+		}
+		if err := m.baseWriter().SetPanelState(switchState, currentLimitA); err != nil {
+			return err
+		}
+		m.lastModeChange = time.Now().UTC()
+		return nil
+	})
+}
+
+func (m *ManagedWriter) SetStandbyWithSource(source CommandSource, enabled bool) error {
+	return m.apply(source, "set_standby", func() error {
+		if err := m.ensureProfileAllows("set_standby"); err != nil {
+			return err
+		}
+		return m.baseWriter().SetStandby(enabled)
+	})
+}
+
+func (m *ManagedWriter) History(limit int) []CommandEvent {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	if limit <= 0 || limit > len(m.events) {
+		limit = len(m.events)
+	}
+	out := make([]CommandEvent, limit)
+	if limit > 0 {
+		copy(out, m.events[len(m.events)-limit:])
+	}
+	return out
+}
+
+func (m *ManagedWriter) apply(source CommandSource, kind string, fn func() error) error {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+
+	if m.writer == nil {
+		err := errors.New("settings writer is not available")
+		m.recordLocked(source, kind, false, err)
+		return err
+	}
+	if m.policy.LockoutWindow > 0 && time.Now().UTC().Before(m.lockoutUntil) {
+		err := fmt.Errorf("command denied during lockout window until %s", m.lockoutUntil.Format(time.RFC3339))
+		m.recordLocked(source, kind, false, err)
+		return err
+	}
+
+	if err := fn(); err != nil {
+		m.recordLocked(source, kind, false, err)
+		return err
+	}
+	if m.policy.LockoutWindow > 0 {
+		m.lockoutUntil = time.Now().UTC().Add(m.policy.LockoutWindow)
+	}
+	m.recordLocked(source, kind, true, nil)
+	return nil
+}
+
+func (m *ManagedWriter) ensureProfileAllows(kind string) error {
+	switch m.policy.Profile {
+	case WriterProfileReadOnly:
+		return errors.New("write denied by read-only profile")
+	case WriterProfileMaintenance:
+		if kind == "set_standby" || kind == "set_panel_state" {
+			return nil
+		}
+		return fmt.Errorf("maintenance profile blocks %s", kind)
+	default:
+		return nil
+	}
+}
+
+func (m *ManagedWriter) recordLocked(source CommandSource, kind string, allowed bool, err error) {
+	event := CommandEvent{
+		Timestamp: time.Now().UTC(),
+		Source:    source,
+		Kind:      kind,
+		Allowed:   allowed,
+	}
+	if err != nil {
+		event.Error = err.Error()
+	}
+	m.events = append(m.events, event)
+	if len(m.events) > 100 {
+		m.events = m.events[len(m.events)-100:]
+	}
+}
+
+func (m *ManagedWriter) baseWriter() SettingsWriter {
+	return m.writer
+}
+
+func panelStateLabel(state PanelSwitchState) string {
+	switch state {
+	case PanelSwitchOn:
+		return "on"
+	case PanelSwitchOff:
+		return "off"
+	case PanelSwitchChargerOnly:
+		return "charger_only"
+	case PanelSwitchInverterOnly:
+		return "inverter_only"
+	default:
+		return fmt.Sprintf("unknown(0x%02x)", byte(state))
+	}
+}
+
+func stringsForAllowedPanelStates(states map[PanelSwitchState]struct{}) string {
+	if len(states) == 0 {
+		return "<none>"
+	}
+	labels := make([]string, 0, len(states))
+	for state := range states {
+		labels = append(labels, panelStateLabel(state))
+	}
+	sort.Strings(labels)
+	return fmt.Sprintf("%v", labels)
+}

mk2driver/managed_writer_test.go

@@ -0,0 +1,97 @@
+package mk2driver
+
+import (
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+type writerStub struct {
+	settingWrites int
+	ramWrites     int
+	panelWrites   int
+	standbyWrites int
+}
+
+func (w *writerStub) WriteRAMVar(id uint16, value int16) error {
+	w.ramWrites++
+	return nil
+}
+
+func (w *writerStub) WriteSetting(id uint16, value int16) error {
+	w.settingWrites++
+	return nil
+}
+
+func (w *writerStub) SetPanelState(switchState PanelSwitchState, currentLimitA *float64) error {
+	w.panelWrites++
+	return nil
+}
+
+func (w *writerStub) SetStandby(enabled bool) error {
+	w.standbyWrites++
+	return nil
+}
+
+func TestManagedWriterReadOnlyProfile(t *testing.T) {
+	base := &writerStub{}
+	managed := NewManagedWriter(base, WriterPolicy{
+		Profile: WriterProfileReadOnly,
+	})
+
+	err := managed.WriteSettingWithSource(CommandSourceMQTT, 1, 1)
+	assert.Error(t, err)
+	assert.Equal(t, 0, base.settingWrites)
+	history := managed.History(10)
+	if assert.Len(t, history, 1) {
+		assert.False(t, history[0].Allowed)
+		assert.Equal(t, CommandSourceMQTT, history[0].Source)
+	}
+}
+
+func TestManagedWriterCurrentLimitGuard(t *testing.T) {
+	base := &writerStub{}
+	max := 16.0
+	managed := NewManagedWriter(base, WriterPolicy{
+		Profile:          WriterProfileNormal,
+		MaxCurrentLimitA: &max,
+	})
+
+	limit := 20.0
+	err := managed.SetPanelStateWithSource(CommandSourceUI, PanelSwitchOn, &limit)
+	assert.Error(t, err)
+	assert.Equal(t, 0, base.panelWrites)
+}
+
+func TestManagedWriterModeRateLimit(t *testing.T) {
+	base := &writerStub{}
+	managed := NewManagedWriter(base, WriterPolicy{
+		Profile:               WriterProfileNormal,
+		ModeChangeMinInterval: 10 * time.Second,
+	})
+
+	err := managed.SetPanelStateWithSource(CommandSourceAutomation, PanelSwitchOn, nil)
+	assert.NoError(t, err)
+	err = managed.SetPanelStateWithSource(CommandSourceAutomation, PanelSwitchOff, nil)
+	assert.Error(t, err)
+	assert.Equal(t, 1, base.panelWrites)
+}
+
+func TestManagedWriterPanelModeAllowlist(t *testing.T) {
+	base := &writerStub{}
+	managed := NewManagedWriter(base, WriterPolicy{
+		Profile: WriterProfileNormal,
+		AllowedPanelStates: map[PanelSwitchState]struct{}{
+			PanelSwitchOff: {},
+		},
+	})
+
+	err := managed.SetPanelStateWithSource(CommandSourceMQTT, PanelSwitchOn, nil)
+	assert.Error(t, err)
+	assert.Equal(t, 0, base.panelWrites)
+
+	err = managed.SetPanelStateWithSource(CommandSourceMQTT, PanelSwitchOff, nil)
+	assert.NoError(t, err)
+	assert.Equal(t, 1, base.panelWrites)
+}

mk2driver/metadata.go

@@ -0,0 +1,332 @@
+package mk2driver
+
+import (
+	"fmt"
+	"math"
+	"sort"
+	"time"
+)
+
+const (
+	defaultTransactionRetries    = 2
+	defaultTransactionRetryDelay = 200 * time.Millisecond
+	defaultTransactionBackoff    = 1.5
+	fastCommandTimeout           = 1500 * time.Millisecond
+	standardCommandTimeout       = 3 * time.Second
+	slowCommandTimeout           = 6 * time.Second
+)
+
+type registerKey struct {
+	kind RegisterKind
+	id   uint16
+}
+
+func int16Ptr(v int16) *int16 {
+	return &v
+}
+
+var knownRegisterMetadata = map[registerKey]RegisterMetadata{
+	{kind: RegisterKindRAMVar, id: ramVarVMains}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarVMains,
+		Name:        "mains_voltage",
+		Description: "AC input mains voltage (scaled)",
+		Unit:        "V",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarIMains}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarIMains,
+		Name:        "mains_current",
+		Description: "AC input mains current (scaled)",
+		Unit:        "A",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarVInverter}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarVInverter,
+		Name:        "inverter_voltage",
+		Description: "AC output inverter voltage (scaled)",
+		Unit:        "V",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarIInverter}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarIInverter,
+		Name:        "inverter_current",
+		Description: "AC output inverter current (scaled)",
+		Unit:        "A",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarVBat}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarVBat,
+		Name:        "battery_voltage",
+		Description: "Battery voltage (scaled)",
+		Unit:        "V",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarIBat}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarIBat,
+		Name:        "battery_current",
+		Description: "Battery current (scaled)",
+		Unit:        "A",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarVBatRipple}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarVBatRipple,
+		Name:        "battery_voltage_ripple",
+		Description: "Battery ripple voltage (scaled)",
+		Unit:        "V",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarInverterPeriod}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarInverterPeriod,
+		Name:        "inverter_period",
+		Description: "Inverter period source value",
+		Unit:        "ticks",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarMainPeriod}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarMainPeriod,
+		Name:        "mains_period",
+		Description: "Mains period source value",
+		Unit:        "ticks",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarIACLoad}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarIACLoad,
+		Name:        "ac_load_current",
+		Description: "AC load current (scaled)",
+		Unit:        "A",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarVirSwitchPos}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarVirSwitchPos,
+		Name:        "virtual_switch_position",
+		Description: "Virtual switch position",
+		Unit:        "state",
+		Scale:       1,
+		Writable:    true,
+		Signed:      false,
+		MinValue:    int16Ptr(0),
+		MaxValue:    int16Ptr(255),
+		SafetyClass: RegisterSafetyGuarded,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarIgnACInState}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarIgnACInState,
+		Name:        "ignored_ac_input_state",
+		Description: "AC input state as seen by firmware",
+		Unit:        "state",
+		Scale:       1,
+		Writable:    false,
+		Signed:      false,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarMultiFuncRelay}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarMultiFuncRelay,
+		Name:        "multifunction_relay",
+		Description: "Multifunction relay state",
+		Unit:        "state",
+		Scale:       1,
+		Writable:    true,
+		Signed:      false,
+		MinValue:    int16Ptr(0),
+		MaxValue:    int16Ptr(1),
+		SafetyClass: RegisterSafetyOperational,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarChargeState}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarChargeState,
+		Name:        "battery_charge_state",
+		Description: "Battery charge state fraction",
+		Unit:        "fraction",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarInverterPower1}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarInverterPower1,
+		Name:        "inverter_power_1",
+		Description: "Inverter power source register 1",
+		Unit:        "W",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarInverterPower2}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarInverterPower2,
+		Name:        "inverter_power_2",
+		Description: "Inverter power source register 2",
+		Unit:        "W",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+	{kind: RegisterKindRAMVar, id: ramVarOutPower}: {
+		Kind:        RegisterKindRAMVar,
+		ID:          ramVarOutPower,
+		Name:        "output_power",
+		Description: "Output power source register",
+		Unit:        "W",
+		Scale:       1,
+		Writable:    false,
+		Signed:      true,
+		SafetyClass: RegisterSafetyReadOnly,
+	},
+}
+
+func normalizeTransactionOptions(opts TransactionOptions) TransactionOptions {
+	if opts.Retries < 0 {
+		opts.Retries = 0
+	}
+	if opts.RetryDelay < 0 {
+		opts.RetryDelay = 0
+	}
+	if opts.BackoffFactor <= 0 {
+		opts.BackoffFactor = defaultTransactionBackoff
+	}
+	if opts.Retries == 0 && opts.RetryDelay == 0 && !opts.ReadBeforeWrite && !opts.VerifyAfterWrite {
+		opts.Retries = defaultTransactionRetries
+		opts.RetryDelay = defaultTransactionRetryDelay
+		opts.BackoffFactor = defaultTransactionBackoff
+		opts.ReadBeforeWrite = true
+		opts.VerifyAfterWrite = true
+		opts.TimeoutClass = TimeoutClassStandard
+		return opts
+	}
+	if opts.RetryDelay == 0 {
+		opts.RetryDelay = defaultTransactionRetryDelay
+	}
+	if opts.TimeoutClass == "" {
+		opts.TimeoutClass = TimeoutClassStandard
+	}
+	return opts
+}
+
+func lookupRegisterMetadata(kind RegisterKind, id uint16) (RegisterMetadata, bool) {
+	meta, ok := knownRegisterMetadata[registerKey{kind: kind, id: id}]
+	if ok {
+		meta = withMetadataDefaults(meta)
+	}
+	return meta, ok
+}
+
+func listRegisterMetadata() []RegisterMetadata {
+	out := make([]RegisterMetadata, 0, len(knownRegisterMetadata))
+	for _, meta := range knownRegisterMetadata {
+		out = append(out, withMetadataDefaults(meta))
+	}
+	sort.Slice(out, func(i, j int) bool {
+		if out[i].Kind != out[j].Kind {
+			return out[i].Kind < out[j].Kind
+		}
+		return out[i].ID < out[j].ID
+	})
+	return out
+}
+
+func validateValueAgainstMetadata(meta RegisterMetadata, value int16) error {
+	if meta.MinValue != nil && value < *meta.MinValue {
+		return fmt.Errorf("value %d is below minimum %d for %s:%d", value, *meta.MinValue, meta.Kind, meta.ID)
+	}
+	if meta.MaxValue != nil && value > *meta.MaxValue {
+		return fmt.Errorf("value %d is above maximum %d for %s:%d", value, *meta.MaxValue, meta.Kind, meta.ID)
+	}
+	return nil
+}
+
+func withMetadataDefaults(meta RegisterMetadata) RegisterMetadata {
+	if meta.Scale == 0 {
+		meta.Scale = 1
+	}
+	if meta.SafetyClass == "" {
+		if meta.Writable {
+			meta.SafetyClass = RegisterSafetyGuarded
+		} else {
+			meta.SafetyClass = RegisterSafetyReadOnly
+		}
+	}
+	return meta
+}
+
+func resolveCommandTimeout(opts TransactionOptions) time.Duration {
+	if opts.CommandTimeout > 0 {
+		return opts.CommandTimeout
+	}
+	switch opts.TimeoutClass {
+	case TimeoutClassFast:
+		return fastCommandTimeout
+	case TimeoutClassSlow:
+		return slowCommandTimeout
+	default:
+		return standardCommandTimeout
+	}
+}
+
+func retryDelayForAttempt(opts TransactionOptions, attempt int) time.Duration {
+	if opts.RetryDelay <= 0 || attempt <= 1 {
+		return opts.RetryDelay
+	}
+	factor := math.Pow(opts.BackoffFactor, float64(attempt-1))
+	delay := float64(opts.RetryDelay) * factor
+	return time.Duration(delay)
+}
+
+func defaultWritableRegisterAddresses() []RegisterAddress {
+	metas := listRegisterMetadata()
+	out := make([]RegisterAddress, 0, len(metas))
+	for _, meta := range metas {
+		if !meta.Writable {
+			continue
+		}
+		out = append(out, RegisterAddress{
+			Kind: meta.Kind,
+			ID:   meta.ID,
+		})
+	}
+	return out
+}

mk2driver/mk2interface.go

@@ -76,3 +76,277 @@ type Mk2 interface {
 	C() chan *Mk2Info
 	Close()
 }
+
+type PanelSwitchState byte
+
+const (
+	// PanelSwitchChargerOnly enables charging only.
+	PanelSwitchChargerOnly PanelSwitchState = 0x01
+	// PanelSwitchInverterOnly enables inverter output and disables charging.
+	PanelSwitchInverterOnly PanelSwitchState = 0x02
+	// PanelSwitchOn enables both inverter and charger.
+	PanelSwitchOn PanelSwitchState = 0x03
+	// PanelSwitchOff disables inverter and charger.
+	PanelSwitchOff PanelSwitchState = 0x04
+)
+
+type SettingsWriter interface {
+	// WriteRAMVar writes a signed 16-bit value to a RAM variable id.
+	WriteRAMVar(id uint16, value int16) error
+	// WriteSetting writes a signed 16-bit value to a setting id.
+	WriteSetting(id uint16, value int16) error
+	// SetPanelState sends the MK2 "S" command using a virtual panel switch state.
+	// If currentLimitA is nil, the command does not update the AC current limit.
+	SetPanelState(switchState PanelSwitchState, currentLimitA *float64) error
+	// SetStandby configures the remote panel standby line.
+	// When enabled, the inverter is prevented from sleeping while switched off.
+	SetStandby(enabled bool) error
+}
+
+type DeviceState byte
+
+const (
+	// DeviceStateChargerOnly enables charging only.
+	DeviceStateChargerOnly DeviceState = 0x02
+	// DeviceStateInverterOnly enables inverter output and disables charging.
+	DeviceStateInverterOnly DeviceState = 0x03
+	// DeviceStateOn enables both inverter and charger.
+	DeviceStateOn DeviceState = 0x04
+	// DeviceStateOff disables inverter and charger.
+	DeviceStateOff DeviceState = 0x05
+)
+
+var DeviceStateNames = map[DeviceState]string{
+	DeviceStateChargerOnly:  "charger_only",
+	DeviceStateInverterOnly: "inverter_only",
+	DeviceStateOn:           "on",
+	DeviceStateOff:          "off",
+}
+
+type RAMVarInfo struct {
+	ID        uint16
+	Scale     int16
+	Offset    int16
+	Factor    float64
+	Signed    bool
+	Supported bool
+}
+
+// ProtocolControl exposes protocol 3.14 command paths for direct MK2 control.
+type ProtocolControl interface {
+	SettingsWriter
+	// GetDeviceState returns the current VE.Bus state using command 0x0E.
+	GetDeviceState() (DeviceState, error)
+	// SetDeviceState sets the VE.Bus state using command 0x0E.
+	SetDeviceState(state DeviceState) error
+	// ReadRAMVarByID reads a RAM variable via command 0x30.
+	ReadRAMVarByID(id uint16) (int16, error)
+	// ReadSettingByID reads a setting via command 0x31.
+	ReadSettingByID(id uint16) (int16, error)
+	// SelectRAMVar selects a RAM variable for follow-up read-selected/write-selected paths.
+	SelectRAMVar(id uint16) error
+	// SelectSetting selects a setting for follow-up read-selected/write-selected paths.
+	SelectSetting(id uint16) error
+	// ReadSelected reads the currently selected value via command 0x35.
+	ReadSelected() (int16, error)
+	// ReadRAMVarInfo reads RAM variable metadata via command 0x36.
+	ReadRAMVarInfo(id uint16) (RAMVarInfo, error)
+	// WriteSelectedData writes to the currently selected register via command 0x34.
+	WriteSelectedData(value int16) error
+	// WriteSettingBySelection performs 0x33 (select setting) followed by 0x34 (write data).
+	WriteSettingBySelection(id uint16, value int16) error
+	// WriteRAMVarBySelection performs 0x32 (select RAM var) followed by 0x34 (write data).
+	WriteRAMVarBySelection(id uint16, value int16) error
+	// WriteSettingByID writes a setting via command 0x37.
+	WriteSettingByID(id uint16, value int16) error
+	// WriteRAMVarByID writes a RAM variable via command 0x38.
+	WriteRAMVarByID(id uint16, value int16) error
+}
+
+type RegisterKind string
+
+const (
+	RegisterKindSetting RegisterKind = "setting"
+	RegisterKindRAMVar  RegisterKind = "ram_var"
+)
+
+type RegisterSafetyClass string
+
+const (
+	// RegisterSafetyReadOnly indicates no write path should be exposed.
+	RegisterSafetyReadOnly RegisterSafetyClass = "read_only"
+	// RegisterSafetyOperational indicates normal runtime write usage is expected.
+	RegisterSafetyOperational RegisterSafetyClass = "operational"
+	// RegisterSafetyGuarded indicates writes should be policy-guarded.
+	RegisterSafetyGuarded RegisterSafetyClass = "guarded"
+	// RegisterSafetyCritical indicates high-impact settings that need stricter controls.
+	RegisterSafetyCritical RegisterSafetyClass = "critical"
+)
+
+type TimeoutClass string
+
+const (
+	TimeoutClassFast     TimeoutClass = "fast"
+	TimeoutClassStandard TimeoutClass = "standard"
+	TimeoutClassSlow     TimeoutClass = "slow"
+)
+
+// RegisterMetadata documents known MK2 register IDs and expected value behavior.
+type RegisterMetadata struct {
+	Kind        RegisterKind
+	ID          uint16
+	Name        string
+	Description string
+	Unit        string
+	Scale       float64
+	Writable    bool
+	Signed      bool
+	MinValue    *int16
+	MaxValue    *int16
+	SafetyClass RegisterSafetyClass
+}
+
+// TransactionOptions controls retry and verification semantics for safe writes.
+type TransactionOptions struct {
+	// Retries is the number of additional write attempts after the first try.
+	Retries int
+	// RetryDelay is slept between retries. Zero uses a sensible default.
+	RetryDelay time.Duration
+	// BackoffFactor multiplies retry delay for each additional attempt (1 disables backoff).
+	BackoffFactor float64
+	// ReadBeforeWrite captures previous value before writing when possible.
+	ReadBeforeWrite bool
+	// VerifyAfterWrite reads the register back and compares with written value.
+	VerifyAfterWrite bool
+	// TimeoutClass applies standard timeout buckets when CommandTimeout is not set.
+	TimeoutClass TimeoutClass
+	// CommandTimeout overrides timeout class for each protocol command inside the transaction.
+	CommandTimeout time.Duration
+}
+
+// RegisterTransactionResult reports details about a transactional register write.
+type RegisterTransactionResult struct {
+	Kind          RegisterKind
+	ID            uint16
+	TargetValue   int16
+	PreviousValue *int16
+	VerifiedValue *int16
+	Attempts      int
+	Timeout       time.Duration
+	Duration      time.Duration
+}
+
+// MetadataControl adds register metadata and transactional safety helpers.
+type MetadataControl interface {
+	ProtocolControl
+	// RegisterMetadata returns metadata for a known register.
+	RegisterMetadata(kind RegisterKind, id uint16) (RegisterMetadata, bool)
+	// ListRegisterMetadata returns all known register metadata.
+	ListRegisterMetadata() []RegisterMetadata
+	// ReadRegister reads a setting or RAM var by kind and id.
+	ReadRegister(kind RegisterKind, id uint16) (int16, error)
+	// WriteRegister performs a safe transactional write with optional retry/verify.
+	WriteRegister(kind RegisterKind, id uint16, value int16, opts TransactionOptions) (RegisterTransactionResult, error)
+}
+
+type RegisterAddress struct {
+	Kind RegisterKind `json:"kind"`
+	ID   uint16       `json:"id"`
+}
+
+type RegisterSnapshotEntry struct {
+	Kind       RegisterKind        `json:"kind"`
+	ID         uint16              `json:"id"`
+	Name       string              `json:"name,omitempty"`
+	Value      int16               `json:"value"`
+	Writable   bool                `json:"writable"`
+	Safety     RegisterSafetyClass `json:"safety_class,omitempty"`
+	CapturedAt time.Time           `json:"captured_at"`
+}
+
+type RegisterSnapshot struct {
+	CapturedAt time.Time               `json:"captured_at"`
+	Entries    []RegisterSnapshotEntry `json:"entries"`
+}
+
+type SnapshotDiff struct {
+	Kind      RegisterKind        `json:"kind"`
+	ID        uint16              `json:"id"`
+	Name      string              `json:"name,omitempty"`
+	Current   int16               `json:"current"`
+	Target    int16               `json:"target"`
+	Changed   bool                `json:"changed"`
+	Writable  bool                `json:"writable"`
+	Safety    RegisterSafetyClass `json:"safety_class,omitempty"`
+	DiffValue int32               `json:"diff_value"`
+}
+
+type SnapshotRestoreResult struct {
+	Applied        []RegisterTransactionResult `json:"applied"`
+	RolledBack     bool                        `json:"rolled_back"`
+	RollbackErrors []string                    `json:"rollback_errors,omitempty"`
+}
+
+// SnapshotControl provides register snapshot, diff preview, and rollback-aware restore.
+type SnapshotControl interface {
+	MetadataControl
+	// CaptureSnapshot reads the provided register list. Empty addresses captures known writable registers.
+	CaptureSnapshot(addresses []RegisterAddress) (RegisterSnapshot, error)
+	// DiffSnapshot compares current values against a snapshot.
+	DiffSnapshot(snapshot RegisterSnapshot) ([]SnapshotDiff, error)
+	// RestoreSnapshot applies snapshot target values; if restore fails mid-way it attempts rollback.
+	RestoreSnapshot(snapshot RegisterSnapshot, opts TransactionOptions) (SnapshotRestoreResult, error)
+}
+
+type TraceDirection string
+
+const (
+	TraceDirectionTX TraceDirection = "tx"
+	TraceDirectionRX TraceDirection = "rx"
+)
+
+type ProtocolTrace struct {
+	Timestamp time.Time      `json:"timestamp"`
+	Direction TraceDirection `json:"direction"`
+	Frame     string         `json:"frame"`
+	Command   string         `json:"command,omitempty"`
+	BytesHex  string         `json:"bytes_hex"`
+}
+
+type DriverDiagnostics struct {
+	GeneratedAt      time.Time       `json:"generated_at"`
+	HealthScore      int             `json:"health_score"`
+	LastFrameAt      *time.Time      `json:"last_frame_at,omitempty"`
+	CommandTimeouts  uint64          `json:"command_timeouts"`
+	CommandFailures  uint64          `json:"command_failures"`
+	ChecksumFailures uint64          `json:"checksum_failures"`
+	RecentErrors     []string        `json:"recent_errors,omitempty"`
+	Traces           []ProtocolTrace `json:"traces"`
+}
+
+// DiagnosticsControl exposes recent protocol traces and health information for troubleshooting bundles.
+type DiagnosticsControl interface {
+	DriverDiagnostics(limit int) DriverDiagnostics
+}
+
+type CommandSource string
+
+const (
+	CommandSourceUnknown    CommandSource = "unknown"
+	CommandSourceUI         CommandSource = "ui"
+	CommandSourceMQTT       CommandSource = "mqtt"
+	CommandSourceAutomation CommandSource = "automation"
+)
+
+// SourceAwareSettingsWriter accepts source tags for arbitration and diagnostics.
+type SourceAwareSettingsWriter interface {
+	SettingsWriter
+	WriteRAMVarWithSource(source CommandSource, id uint16, value int16) error
+	WriteSettingWithSource(source CommandSource, id uint16, value int16) error
+	SetPanelStateWithSource(source CommandSource, switchState PanelSwitchState, currentLimitA *float64) error
+	SetStandbyWithSource(source CommandSource, enabled bool) error
+}
+
+type CommandHistoryProvider interface {
+	History(limit int) []CommandEvent
+}

mk2driver/mockmk2.go

@@ -8,6 +8,8 @@ type mock struct {
 	c chan *Mk2Info
 }
 
+var _ ProtocolControl = (*mock)(nil)
+
 func NewMk2Mock() Mk2 {
 	tmp := &mock{
 		c: make(chan *Mk2Info, 1),
@@ -37,6 +39,77 @@ func (m *mock) Close() {
 
 }
 
+func (m *mock) WriteRAMVar(_ uint16, _ int16) error {
+	return nil
+}
+
+func (m *mock) WriteSetting(_ uint16, _ int16) error {
+	return nil
+}
+
+func (m *mock) SetPanelState(_ PanelSwitchState, _ *float64) error {
+	return nil
+}
+
+func (m *mock) SetStandby(_ bool) error {
+	return nil
+}
+
+func (m *mock) GetDeviceState() (DeviceState, error) {
+	return DeviceStateOn, nil
+}
+
+func (m *mock) SetDeviceState(_ DeviceState) error {
+	return nil
+}
+
+func (m *mock) ReadRAMVarByID(_ uint16) (int16, error) {
+	return 0, nil
+}
+
+func (m *mock) ReadSettingByID(_ uint16) (int16, error) {
+	return 0, nil
+}
+
+func (m *mock) SelectRAMVar(_ uint16) error {
+	return nil
+}
+
+func (m *mock) SelectSetting(_ uint16) error {
+	return nil
+}
+
+func (m *mock) ReadSelected() (int16, error) {
+	return 0, nil
+}
+
+func (m *mock) ReadRAMVarInfo(id uint16) (RAMVarInfo, error) {
+	return RAMVarInfo{
+		ID:        id,
+		Supported: false,
+	}, nil
+}
+
+func (m *mock) WriteSettingByID(_ uint16, _ int16) error {
+	return nil
+}
+
+func (m *mock) WriteRAMVarByID(_ uint16, _ int16) error {
+	return nil
+}
+
+func (m *mock) WriteSelectedData(_ int16) error {
+	return nil
+}
+
+func (m *mock) WriteSettingBySelection(_ uint16, _ int16) error {
+	return nil
+}
+
+func (m *mock) WriteRAMVarBySelection(_ uint16, _ int16) error {
+	return nil
+}
+
 func (m *mock) genMockValues() {
 	mult := 1.0
 	ledState := LedOff

plugins/cli/cli.go

@@ -1,12 +1,12 @@
 package cli
 
 import (
-	"fmt"
-	"log"
-
-	"github.com/diebietse/invertergui/mk2driver"
+	"git.coadcorp.com/nathan/invertergui/mk2driver"
+	"github.com/sirupsen/logrus"
 )
 
+var log = logrus.WithField("ctx", "inverter-gui-cli")
+
 type Cli struct {
 	mk2driver.Mk2
 }
@@ -27,21 +27,21 @@ func (c *Cli) run() {
 }
 
 func printInfo(info *mk2driver.Mk2Info) {
-	out := fmt.Sprintf("Version: %v\n", info.Version)
-	out += fmt.Sprintf("Bat Volt: %.2fV Bat Cur: %.2fA \n", info.BatVoltage, info.BatCurrent)
-	out += fmt.Sprintf("In Volt: %.2fV In Cur: %.2fA In Freq %.2fHz\n", info.InVoltage, info.InCurrent, info.InFrequency)
-	out += fmt.Sprintf("Out Volt: %.2fV Out Cur: %.2fA Out Freq %.2fHz\n", info.OutVoltage, info.OutCurrent, info.OutFrequency)
-	out += fmt.Sprintf("In Power %.2fW Out Power %.2fW\n", info.InVoltage*info.InCurrent, info.OutVoltage*info.OutCurrent)
-	out += fmt.Sprintf("Charge State: %.2f%%\n", info.ChargeState*100)
-	out += "LEDs state:"
+	log.Infof("Version: %v", info.Version)
+	log.Infof("Bat Volt: %.2fV Bat Cur: %.2fA", info.BatVoltage, info.BatCurrent)
+	log.Infof("In Volt: %.2fV In Cur: %.2fA In Freq %.2fHz", info.InVoltage, info.InCurrent, info.InFrequency)
+	log.Infof("Out Volt: %.2fV Out Cur: %.2fA Out Freq %.2fHz", info.OutVoltage, info.OutCurrent, info.OutFrequency)
+	log.Infof("In Power %.2fW Out Power %.2fW", info.InVoltage*info.InCurrent, info.OutVoltage*info.OutCurrent)
+	log.Infof("Charge State: %.2f%%", info.ChargeState*100)
+	log.Info("LEDs state:")
 	for k, v := range info.LEDs {
-		out += fmt.Sprintf(" %s %s", mk2driver.LedNames[k], mk2driver.StateNames[v])
+		log.Infof(" %s %s", mk2driver.LedNames[k], mk2driver.StateNames[v])
 	}
 
-	out += "\nErrors:"
-	for _, v := range info.Errors {
-		out += " " + v.Error()
+	if len(info.Errors) != 0 {
+		log.Info("Errors:")
+		for _, err := range info.Errors {
+			log.Error(err)
+		}
 	}
-	out += "\n"
-	log.Printf("System Info: \n%v", out)
 }

plugins/mqttclient/mqtt_test.go

@@ -0,0 +1,503 @@
+package mqttclient
+
+import (
+	"testing"
+	"time"
+
+	"git.coadcorp.com/nathan/invertergui/mk2driver"
+	"github.com/stretchr/testify/assert"
+)
+
+type fakeWriter struct {
+	lastKind         string
+	lastID           uint16
+	lastValue        int16
+	lastSwitchState  mk2driver.PanelSwitchState
+	lastCurrentLimit *float64
+	lastStandby      *bool
+	err              error
+}
+
+func (f *fakeWriter) WriteRAMVar(id uint16, value int16) error {
+	f.lastKind = commandKindRAMVar
+	f.lastID = id
+	f.lastValue = value
+	return f.err
+}
+
+func (f *fakeWriter) WriteSetting(id uint16, value int16) error {
+	f.lastKind = commandKindSetting
+	f.lastID = id
+	f.lastValue = value
+	return f.err
+}
+
+func (f *fakeWriter) SetPanelState(switchState mk2driver.PanelSwitchState, currentLimitA *float64) error {
+	f.lastKind = commandKindPanel
+	f.lastSwitchState = switchState
+	f.lastCurrentLimit = currentLimitA
+	return f.err
+}
+
+func (f *fakeWriter) SetStandby(standby bool) error {
+	f.lastKind = commandKindStandby
+	f.lastStandby = &standby
+	return f.err
+}
+
+func Test_decodeWriteCommand(t *testing.T) {
+	currentLimit := 16.5
+	tests := []struct {
+		name    string
+		payload string
+		check   func(*testing.T, writeCommand)
+		wantErr string
+	}{
+		{
+			name:    "setting",
+			payload: `{"request_id":"abc","kind":"setting","id":15,"value":-5}`,
+			check: func(t *testing.T, got writeCommand) {
+				assert.Equal(t, writeCommand{
+					Source:    mk2driver.CommandSourceMQTT,
+					RequestID: "abc",
+					Kind:      commandKindSetting,
+					ID:        15,
+					Value:     -5,
+				}, got)
+			},
+		},
+		{
+			name:    "ram_var alias from type",
+			payload: `{"type":"ramvar","id":2,"value":7}`,
+			check: func(t *testing.T, got writeCommand) {
+				assert.Equal(t, writeCommand{
+					Source: mk2driver.CommandSourceMQTT,
+					Kind:   commandKindRAMVar,
+					ID:     2,
+					Value:  7,
+				}, got)
+			},
+		},
+		{
+			name:    "panel state",
+			payload: `{"kind":"panel_state","switch":"on","current_limit":16.5}`,
+			check: func(t *testing.T, got writeCommand) {
+				assert.Equal(t, commandKindPanel, got.Kind)
+				assert.True(t, got.HasSwitch)
+				assert.Equal(t, mk2driver.PanelSwitchOn, got.SwitchState)
+				assert.Equal(t, "on", got.SwitchName)
+				if assert.NotNil(t, got.CurrentLimitA) {
+					assert.Equal(t, currentLimit, *got.CurrentLimitA)
+				}
+			},
+		},
+		{
+			name:    "panel current limit only",
+			payload: `{"kind":"panel_state","current_limit":12.0}`,
+			check: func(t *testing.T, got writeCommand) {
+				assert.Equal(t, commandKindPanel, got.Kind)
+				assert.False(t, got.HasSwitch)
+				assert.Nil(t, got.Standby)
+				if assert.NotNil(t, got.CurrentLimitA) {
+					assert.Equal(t, 12.0, *got.CurrentLimitA)
+				}
+			},
+		},
+		{
+			name:    "standby bool",
+			payload: `{"kind":"standby","standby":true}`,
+			check: func(t *testing.T, got writeCommand) {
+				assert.Equal(t, commandKindStandby, got.Kind)
+				if assert.NotNil(t, got.Standby) {
+					assert.True(t, *got.Standby)
+				}
+			},
+		},
+		{
+			name:    "standby using value string",
+			payload: `{"kind":"standby","value":"OFF"}`,
+			check: func(t *testing.T, got writeCommand) {
+				assert.Equal(t, commandKindStandby, got.Kind)
+				if assert.NotNil(t, got.Standby) {
+					assert.False(t, *got.Standby)
+				}
+			},
+		},
+		{
+			name:    "missing id",
+			payload: `{"kind":"setting","value":1}`,
+			wantErr: `missing required field "id"`,
+		},
+		{
+			name:    "missing panel switch and current limit",
+			payload: `{"kind":"panel_state"}`,
+			wantErr: `missing required field "switch"`,
+		},
+		{
+			name:    "invalid standby",
+			payload: `{"kind":"standby","value":"banana"}`,
+			wantErr: `field "standby" must be true/false`,
+		},
+		{
+			name:    "invalid kind",
+			payload: `{"kind":"unknown","id":1,"value":1}`,
+			wantErr: `unsupported write command kind "unknown"`,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, err := decodeWriteCommand([]byte(tt.payload))
+			if tt.wantErr != "" {
+				assert.Error(t, err)
+				assert.ErrorContains(t, err, tt.wantErr)
+				return
+			}
+
+			assert.NoError(t, err)
+			tt.check(t, got)
+		})
+	}
+}
+
+func Test_executeWriteCommand(t *testing.T) {
+	limit := 8.0
+	standby := true
+	tests := []struct {
+		name string
+		cmd  writeCommand
+		want string
+	}{
+		{
+			name: "setting",
+			cmd: writeCommand{
+				Kind:  commandKindSetting,
+				ID:    9,
+				Value: 2,
+			},
+			want: commandKindSetting,
+		},
+		{
+			name: "ram_var",
+			cmd: writeCommand{
+				Kind:  commandKindRAMVar,
+				ID:    3,
+				Value: -1,
+			},
+			want: commandKindRAMVar,
+		},
+		{
+			name: "panel_state",
+			cmd: writeCommand{
+				Kind:          commandKindPanel,
+				HasSwitch:     true,
+				SwitchState:   mk2driver.PanelSwitchInverterOnly,
+				CurrentLimitA: &limit,
+			},
+			want: commandKindPanel,
+		},
+		{
+			name: "standby",
+			cmd: writeCommand{
+				Kind:    commandKindStandby,
+				Standby: &standby,
+			},
+			want: commandKindStandby,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			writer := &fakeWriter{}
+			err := executeWriteCommand(writer, tt.cmd)
+			assert.NoError(t, err)
+			assert.Equal(t, tt.want, writer.lastKind)
+			switch tt.want {
+			case commandKindPanel:
+				assert.Equal(t, tt.cmd.SwitchState, writer.lastSwitchState)
+				if assert.NotNil(t, writer.lastCurrentLimit) {
+					assert.Equal(t, *tt.cmd.CurrentLimitA, *writer.lastCurrentLimit)
+				}
+			case commandKindStandby:
+				if assert.NotNil(t, writer.lastStandby) {
+					assert.Equal(t, *tt.cmd.Standby, *writer.lastStandby)
+				}
+			default:
+				assert.Equal(t, tt.cmd.ID, writer.lastID)
+				assert.Equal(t, tt.cmd.Value, writer.lastValue)
+			}
+		})
+	}
+}
+
+func Test_buildHADiscoveryDefinitions(t *testing.T) {
+	cfg := Config{
+		Topic:        "invertergui/updates",
+		CommandTopic: "invertergui/settings/set",
+		HomeAssistant: HomeAssistantConfig{
+			Enabled:         true,
+			DiscoveryPrefix: "homeassistant",
+			NodeID:          "victron_main",
+			DeviceName:      "Shed Victron",
+		},
+	}
+
+	definitions := buildHADiscoveryDefinitions(cfg)
+	assert.NotEmpty(t, definitions)
+
+	var panelMode *haDiscoveryDefinition
+	var panelCurrentLimit *haDiscoveryDefinition
+	var panelStandby *haDiscoveryDefinition
+	var batteryVoltage *haDiscoveryDefinition
+	for i := range definitions {
+		def := &definitions[i]
+		if def.Component == "select" && def.ObjectID == "remote_panel_mode" {
+			panelMode = def
+		}
+		if def.Component == "number" && def.ObjectID == "remote_panel_current_limit" {
+			panelCurrentLimit = def
+		}
+		if def.Component == "switch" && def.ObjectID == "remote_panel_standby" {
+			panelStandby = def
+		}
+		if def.Component == "sensor" && def.ObjectID == "battery_voltage" {
+			batteryVoltage = def
+		}
+	}
+
+	if assert.NotNil(t, panelMode) {
+		assert.Equal(t, cfg.CommandTopic, panelMode.Config["command_topic"])
+		assert.Equal(t, haPanelSwitchStateTopic(cfg), panelMode.Config["state_topic"])
+	}
+	if assert.NotNil(t, panelCurrentLimit) {
+		assert.Equal(t, cfg.CommandTopic, panelCurrentLimit.Config["command_topic"])
+		assert.Equal(t, haCurrentLimitStateTopic(cfg), panelCurrentLimit.Config["state_topic"])
+	}
+	if assert.NotNil(t, panelStandby) {
+		assert.Equal(t, cfg.CommandTopic, panelStandby.Config["command_topic"])
+		assert.Equal(t, haStandbyStateTopic(cfg), panelStandby.Config["state_topic"])
+	}
+	if assert.NotNil(t, batteryVoltage) {
+		assert.Equal(t, cfg.Topic, batteryVoltage.Config["state_topic"])
+	}
+}
+
+func Test_panelStateCacheResolvePanelCommand(t *testing.T) {
+	cache := &panelStateCache{}
+
+	_, err := cache.resolvePanelCommand(writeCommand{
+		Kind:          commandKindPanel,
+		CurrentLimitA: float64Ptr(12),
+	})
+	assert.Error(t, err)
+
+	cache.remember(writeCommand{
+		Kind:        commandKindPanel,
+		HasSwitch:   true,
+		SwitchState: mk2driver.PanelSwitchOn,
+		SwitchName:  "on",
+	})
+
+	resolved, err := cache.resolvePanelCommand(writeCommand{
+		Kind:          commandKindPanel,
+		CurrentLimitA: float64Ptr(10),
+	})
+	assert.NoError(t, err)
+	assert.True(t, resolved.HasSwitch)
+	assert.Equal(t, mk2driver.PanelSwitchOn, resolved.SwitchState)
+	assert.Equal(t, "on", resolved.SwitchName)
+}
+
+func Test_normalizeID(t *testing.T) {
+	assert.Equal(t, "victron_main_01", normalizeID("Victron Main #01"))
+	assert.Equal(t, "inverter-gui", normalizeID(" inverter-gui "))
+	assert.Equal(t, "", normalizeID("   "))
+}
+
+func Test_decodeVenusWriteCommand(t *testing.T) {
+	cfg := Config{
+		ClientID: "inverter-gui",
+		Venus: VenusConfig{
+			Enabled:     true,
+			PortalID:    "site01",
+			Service:     "vebus/257",
+			GuideCompat: true,
+		},
+	}
+
+	tests := []struct {
+		name      string
+		topic     string
+		payload   string
+		assertion func(*testing.T, writeCommand)
+		wantErr   string
+	}{
+		{
+			name:    "mode numeric",
+			topic:   "W/site01/vebus/257/Mode",
+			payload: `{"value":3}`,
+			assertion: func(t *testing.T, cmd writeCommand) {
+				assert.Equal(t, commandKindPanel, cmd.Kind)
+				assert.True(t, cmd.HasSwitch)
+				assert.Equal(t, mk2driver.PanelSwitchOn, cmd.SwitchState)
+				assert.Equal(t, "on", cmd.SwitchName)
+			},
+		},
+		{
+			name:    "current limit",
+			topic:   "W/site01/vebus/257/Ac/ActiveIn/CurrentLimit",
+			payload: `{"value":16.5}`,
+			assertion: func(t *testing.T, cmd writeCommand) {
+				assert.Equal(t, commandKindPanel, cmd.Kind)
+				if assert.NotNil(t, cmd.CurrentLimitA) {
+					assert.Equal(t, 16.5, *cmd.CurrentLimitA)
+				}
+			},
+		},
+		{
+			name:    "standby",
+			topic:   "W/site01/vebus/257/Settings/Standby",
+			payload: `{"value":true}`,
+			assertion: func(t *testing.T, cmd writeCommand) {
+				assert.Equal(t, commandKindStandby, cmd.Kind)
+				if assert.NotNil(t, cmd.Standby) {
+					assert.True(t, *cmd.Standby)
+				}
+			},
+		},
+		{
+			name:    "invalid topic",
+			topic:   "W/site01/vebus/257/Unknown",
+			payload: `{"value":1}`,
+			wantErr: "unsupported Venus write path",
+		},
+		{
+			name:    "guide ess setpoint",
+			topic:   "W/site01/settings/0/Settings/CGwacs/AcPowerSetPoint",
+			payload: `{"value":-1200}`,
+			assertion: func(t *testing.T, cmd writeCommand) {
+				assert.Equal(t, commandKindESSSet, cmd.Kind)
+				if assert.NotNil(t, cmd.FloatValue) {
+					assert.InDelta(t, -1200, *cmd.FloatValue, 0.01)
+				}
+			},
+		},
+		{
+			name:    "guide ess mode with prefix",
+			topic:   "victron/W/site01/settings/0/Settings/CGwacs/BatteryLife/State",
+			payload: `{"value":10}`,
+			assertion: func(t *testing.T, cmd writeCommand) {
+				assert.Equal(t, commandKindESSMode, cmd.Kind)
+				assert.Equal(t, int16(10), cmd.Value)
+			},
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			testCfg := cfg
+			if tt.name == "guide ess mode with prefix" {
+				testCfg.Venus.TopicPrefix = "victron"
+			}
+			cmd, err := decodeVenusWriteCommand(testCfg, tt.topic, []byte(tt.payload))
+			if tt.wantErr != "" {
+				assert.Error(t, err)
+				assert.ErrorContains(t, err, tt.wantErr)
+				return
+			}
+			assert.NoError(t, err)
+			tt.assertion(t, cmd)
+		})
+	}
+}
+
+func Test_panelStateCacheRememberTracksFields(t *testing.T) {
+	cache := &panelStateCache{}
+	limit := 12.0
+	standby := true
+
+	cache.remember(writeCommand{
+		Kind:          commandKindPanel,
+		HasSwitch:     true,
+		SwitchName:    "on",
+		SwitchState:   mk2driver.PanelSwitchOn,
+		CurrentLimitA: &limit,
+	})
+	cache.remember(writeCommand{
+		Kind:    commandKindStandby,
+		Standby: &standby,
+	})
+
+	s := cache.snapshot()
+	assert.True(t, s.HasSwitch)
+	assert.Equal(t, "on", s.Switch)
+	assert.True(t, s.HasCurrent)
+	assert.InDelta(t, 12.0, s.CurrentLimit, 0.001)
+	assert.True(t, s.HasStandby)
+	assert.True(t, s.Standby)
+}
+
+func Test_historyTrackerSummary(t *testing.T) {
+	h := newHistoryTracker(2)
+	now := time.Now().UTC()
+
+	h.Add(telemetrySnapshot{
+		Timestamp:      now,
+		InputPower:     100,
+		OutputPower:    90,
+		BatteryPower:   -10,
+		BatteryVoltage: 25.0,
+	}, operatingStatePassthru, 0, nil)
+	summary := h.Add(telemetrySnapshot{
+		Timestamp:      now.Add(1 * time.Second),
+		InputPower:     200,
+		OutputPower:    180,
+		BatteryPower:   -20,
+		BatteryVoltage: 24.5,
+	}, operatingStateInverter, 2, &now)
+
+	assert.Equal(t, 2, summary.Samples)
+	assert.InDelta(t, 150, summary.AverageInputPower, 0.01)
+	assert.InDelta(t, 135, summary.AverageOutputPower, 0.01)
+	assert.InDelta(t, 180, summary.MaxOutputPower, 0.01)
+	assert.InDelta(t, 24.5, summary.MinBatteryVoltage, 0.01)
+	assert.Equal(t, uint64(2), summary.FaultCount)
+}
+
+func Test_resolveESSWriteCommand(t *testing.T) {
+	ess := newESSControlCache()
+	telemetry := &telemetryCache{}
+	telemetry.set(telemetrySnapshot{InputVoltage: 230})
+
+	setpoint := 920.0
+	mapped, err := resolveESSWriteCommand(writeCommand{
+		Kind:       commandKindESSSet,
+		FloatValue: &setpoint,
+	}, ess, telemetry)
+	assert.NoError(t, err)
+	if assert.NotNil(t, mapped) {
+		assert.Equal(t, commandKindPanel, mapped.Kind)
+		assert.Equal(t, "charger_only", mapped.SwitchName)
+		if assert.NotNil(t, mapped.CurrentLimitA) {
+			assert.InDelta(t, 4.0, *mapped.CurrentLimitA, 0.01)
+		}
+	}
+
+	maxDischarge := 1000.0
+	_, err = resolveESSWriteCommand(writeCommand{
+		Kind:       commandKindESSMaxD,
+		FloatValue: &maxDischarge,
+	}, ess, telemetry)
+	assert.NoError(t, err)
+
+	dischargeSetpoint := -2000.0
+	mapped, err = resolveESSWriteCommand(writeCommand{
+		Kind:       commandKindESSSet,
+		FloatValue: &dischargeSetpoint,
+	}, ess, telemetry)
+	assert.NoError(t, err)
+	if assert.NotNil(t, mapped) {
+		assert.Equal(t, commandKindPanel, mapped.Kind)
+		assert.Equal(t, "inverter_only", mapped.SwitchName)
+	}
+}

plugins/munin/munin.go

@@ -36,23 +36,26 @@ import (
 	"net/http"
 	"time"
 
-	"github.com/diebietse/invertergui/mk2driver"
+	"git.coadcorp.com/nathan/invertergui/mk2driver"
+	"github.com/sirupsen/logrus"
 )
 
+var log = logrus.WithField("ctx", "inverter-gui-munin")
+
 type Munin struct {
 	mk2driver.Mk2
-	muninResponse chan *muninData
+	muninResponse chan muninData
 }
 
 type muninData struct {
-	status       *mk2driver.Mk2Info
+	status       mk2driver.Mk2Info
 	timesUpdated int
 }
 
 func NewMunin(mk2 mk2driver.Mk2) *Munin {
 	m := &Munin{
 		Mk2:           mk2,
-		muninResponse: make(chan *muninData),
+		muninResponse: make(chan muninData),
 	}
 
 	go m.run()
@@ -60,17 +63,18 @@ func NewMunin(mk2 mk2driver.Mk2) *Munin {
 	return m
 }
 
-func (m *Munin) ServeMuninHTTP(rw http.ResponseWriter, r *http.Request) {
+func (m *Munin) ServeMuninHTTP(rw http.ResponseWriter, _ *http.Request) {
 	muninDat := <-m.muninResponse
 	if muninDat.timesUpdated == 0 {
+		log.Error("No data returned")
 		rw.WriteHeader(500)
 		_, _ = rw.Write([]byte("No data to return.\n"))
 		return
 	}
-	calcMuninAverages(muninDat)
+	calcMuninAverages(&muninDat)
 
 	status := muninDat.status
-	tmpInput := buildTemplateInput(status)
+	tmpInput := buildTemplateInput(&status)
 	outputBuf := &bytes.Buffer{}
 	fmt.Fprintf(outputBuf, "multigraph in_batvolt\n")
 	fmt.Fprintf(outputBuf, "volt.value %s\n", tmpInput.BatVoltage)
@@ -95,79 +99,75 @@ func (m *Munin) ServeMuninHTTP(rw http.ResponseWriter, r *http.Request) {
 
 	_, err := rw.Write(outputBuf.Bytes())
 	if err != nil {
-		fmt.Printf("%v\n", err)
+		log.Errorf("Could not write data response: %v", err)
 	}
 }
 
-func (m *Munin) ServeMuninConfigHTTP(rw http.ResponseWriter, r *http.Request) {
+func (m *Munin) ServeMuninConfigHTTP(rw http.ResponseWriter, _ *http.Request) {
 	output := muninConfig
 	_, err := rw.Write([]byte(output))
 	if err != nil {
-		fmt.Printf("%v\n", err)
+		log.Errorf("Could not write config response: %v", err)
 	}
 }
 
 func (m *Munin) run() {
 	muninValues := &muninData{
-		status: &mk2driver.Mk2Info{},
+		status: mk2driver.Mk2Info{},
 	}
 	for {
 		select {
 		case e := <-m.C():
 			if e.Valid {
 				calcMuninValues(muninValues, e)
-
 			}
-		case m.muninResponse <- muninValues:
+		case m.muninResponse <- *muninValues:
 			zeroMuninValues(muninValues)
 		}
 	}
 }
 
-//Munin only samples once every 5 minutes so averages have to be calculated for some values.
-func calcMuninValues(muninDat *muninData, newStatus *mk2driver.Mk2Info) {
-	muninDat.timesUpdated++
-	muninVal := muninDat.status
-	muninVal.OutCurrent += newStatus.OutCurrent
-	muninVal.InCurrent += newStatus.InCurrent
-	muninVal.BatCurrent += newStatus.BatCurrent
+// Munin only samples once every 5 minutes so averages have to be calculated for some values.
+func calcMuninValues(m *muninData, newStatus *mk2driver.Mk2Info) {
+	m.timesUpdated++
+	m.status.OutCurrent += newStatus.OutCurrent
+	m.status.InCurrent += newStatus.InCurrent
+	m.status.BatCurrent += newStatus.BatCurrent
 
-	muninVal.OutVoltage += newStatus.OutVoltage
-	muninVal.InVoltage += newStatus.InVoltage
-	muninVal.BatVoltage += newStatus.BatVoltage
+	m.status.OutVoltage += newStatus.OutVoltage
+	m.status.InVoltage += newStatus.InVoltage
+	m.status.BatVoltage += newStatus.BatVoltage
 
-	muninVal.InFrequency = newStatus.InFrequency
-	muninVal.OutFrequency = newStatus.OutFrequency
+	m.status.InFrequency = newStatus.InFrequency
+	m.status.OutFrequency = newStatus.OutFrequency
 
-	muninVal.ChargeState = newStatus.ChargeState
+	m.status.ChargeState = newStatus.ChargeState
 }
 
-func calcMuninAverages(muninDat *muninData) {
-	muninVal := muninDat.status
-	muninVal.OutCurrent /= float64(muninDat.timesUpdated)
-	muninVal.InCurrent /= float64(muninDat.timesUpdated)
-	muninVal.BatCurrent /= float64(muninDat.timesUpdated)
+func calcMuninAverages(m *muninData) {
+	m.status.OutCurrent /= float64(m.timesUpdated)
+	m.status.InCurrent /= float64(m.timesUpdated)
+	m.status.BatCurrent /= float64(m.timesUpdated)
 
-	muninVal.OutVoltage /= float64(muninDat.timesUpdated)
-	muninVal.InVoltage /= float64(muninDat.timesUpdated)
-	muninVal.BatVoltage /= float64(muninDat.timesUpdated)
+	m.status.OutVoltage /= float64(m.timesUpdated)
+	m.status.InVoltage /= float64(m.timesUpdated)
+	m.status.BatVoltage /= float64(m.timesUpdated)
 }
 
-func zeroMuninValues(muninDat *muninData) {
-	muninDat.timesUpdated = 0
-	muninVal := muninDat.status
-	muninVal.OutCurrent = 0
-	muninVal.InCurrent = 0
-	muninVal.BatCurrent = 0
+func zeroMuninValues(m *muninData) {
+	m.timesUpdated = 0
+	m.status.OutCurrent = 0
+	m.status.InCurrent = 0
+	m.status.BatCurrent = 0
 
-	muninVal.OutVoltage = 0
-	muninVal.InVoltage = 0
-	muninVal.BatVoltage = 0
+	m.status.OutVoltage = 0
+	m.status.InVoltage = 0
+	m.status.BatVoltage = 0
 
-	muninVal.InFrequency = 0
-	muninVal.OutFrequency = 0
+	m.status.InFrequency = 0
+	m.status.OutFrequency = 0
 
-	muninVal.ChargeState = 0
+	m.status.ChargeState = 0
 }
 
 type templateInput struct {

plugins/munin/munin_test.go

@@ -0,0 +1,29 @@
+package munin
+
+import (
+	"io"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"git.coadcorp.com/nathan/invertergui/mk2driver"
+)
+
+func TestServer(_ *testing.T) {
+
+	mockMk2 := mk2driver.NewMk2Mock()
+	muninServer := NewMunin(mockMk2)
+
+	ts := httptest.NewServer(http.HandlerFunc(muninServer.ServeMuninHTTP))
+	defer ts.Close()
+
+	res, err := http.Get(ts.URL)
+	if err != nil {
+		log.Fatal(err)
+	}
+	_, err = io.ReadAll(res.Body)
+	res.Body.Close()
+	if err != nil {
+		log.Fatal(err)
+	}
+}

plugins/prometheus/prometheus.go

@@ -31,7 +31,7 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 package prometheus
 
 import (
-	"github.com/diebietse/invertergui/mk2driver"
+	"git.coadcorp.com/nathan/invertergui/mk2driver"
 	"github.com/prometheus/client_golang/prometheus"
 )
 

plugins/webui/static/binary.go

@@ -1,17 +1,14 @@
 package static
 
 import (
-	"github.com/rakyll/statik/fs"
-
-	"log"
+	"embed"
 	"net/http"
 )
 
-// New exports the static part of the webgui that is served via statik
+//go:embed css js index.html favicon.ico
+var content embed.FS
+
+// New exports the static part of the webgui that is served via embed
 func New() http.Handler {
-	statikFs, err := fs.New()
-	if err != nil {
-		log.Fatal(err)
-	}
-	return http.FileServer(statikFs)
+	return http.FileServer(http.FS(content))
 }

plugins/webui/static/index.html

@@ -98,6 +98,117 @@
       <div class="alert alert-danger" role="alert" v-if="error.has_error">
         {{ error.error_message }}
       </div>
+      <div
+        class="alert"
+        v-if="control.message !== ''"
+        v-bind:class="[control.has_error ? 'alert-danger' : 'alert-success']"
+      >
+        {{ control.message }}
+      </div>
+      <div class="row">
+        <div class="col">
+          <div class="card mb-3">
+            <div class="card-body">
+              <h4 class="card-title">Remote Panel Control</h4>
+              <p class="text-muted mb-2">
+                Mode and current limit are applied together, equivalent to
+                <code>set_remote_panel_state</code>.
+              </p>
+              <p class="mb-1">
+                <strong>Current Mode:</strong>
+                {{ remoteModeLabel(state.remote_panel) }}
+              </p>
+              <p class="mb-1">
+                <strong>Current Limit:</strong>
+                {{ state.remote_panel.current_limit === null || state.remote_panel.current_limit === undefined ? 'Unknown' : state.remote_panel.current_limit + ' A' }}
+              </p>
+              <p class="mb-3">
+                <strong>Standby:</strong>
+                {{ remoteStandbyLabel(state.remote_panel) }}
+              </p>
+              <div class="row">
+                <div class="col-md-8">
+                  <form v-on:submit.prevent="applyRemotePanelState">
+                    <div class="form-row">
+                      <div class="form-group col-md-6">
+                        <label for="modeSelect">Remote Panel Mode</label>
+                        <select
+                          class="form-control"
+                          id="modeSelect"
+                          v-model="remote_form.mode"
+                          v-bind:disabled="!state.remote_panel.writable || control.busy"
+                        >
+                          <option value="on">on</option>
+                          <option value="off">off</option>
+                          <option value="charger_only">charger_only</option>
+                          <option value="inverter_only">inverter_only</option>
+                        </select>
+                      </div>
+                      <div class="form-group col-md-6">
+                        <label for="currentLimitInput">AC Input Current Limit (A)</label>
+                        <input
+                          id="currentLimitInput"
+                          type="number"
+                          min="0"
+                          step="0.1"
+                          class="form-control"
+                          v-model="remote_form.current_limit"
+                          placeholder="leave blank to keep current"
+                          v-bind:disabled="!state.remote_panel.writable || control.busy"
+                        />
+                      </div>
+                    </div>
+                    <button
+                      type="submit"
+                      class="btn btn-primary"
+                      v-bind:disabled="!state.remote_panel.writable || control.busy"
+                    >
+                      Apply Mode + Current Limit
+                    </button>
+                  </form>
+                </div>
+                <div class="col-md-4">
+                  <form v-on:submit.prevent="applyStandby">
+                    <div class="form-group">
+                      <div class="form-check mt-4">
+                        <input
+                          id="standbySwitch"
+                          type="checkbox"
+                          class="form-check-input"
+                          v-model="remote_form.standby"
+                          v-bind:disabled="!state.remote_panel.writable || control.busy"
+                        />
+                        <label class="form-check-label" for="standbySwitch">
+                          Prevent sleep while off
+                        </label>
+                      </div>
+                    </div>
+                    <button
+                      type="submit"
+                      class="btn btn-secondary"
+                      v-bind:disabled="!state.remote_panel.writable || control.busy"
+                    >
+                      Apply Standby
+                    </button>
+                  </form>
+                </div>
+              </div>
+              <div class="mt-3 text-muted" v-if="state.remote_panel.last_updated">
+                Last update {{ state.remote_panel.last_updated }}
+                <span v-if="state.remote_panel.last_command">
+                  ({{ state.remote_panel.last_command }})
+                </span>
+              </div>
+              <div class="mt-2 text-danger" v-if="state.remote_panel.last_error">
+                {{ state.remote_panel.last_error }}
+              </div>
+              <div class="mt-2 text-warning" v-if="!state.remote_panel.writable">
+                Remote control is unavailable for this data source.
+              </div>
+            </div>
+          </div>
+        </div>
+      </div>
       <div class="row">
         <div class="col">
           <hr />

plugins/webui/static/js/controller.js

@@ -0,0 +1,280 @@
+var app;
+const timeoutMax = 30000;
+const timeoutMin = 1000;
+var timeout = timeoutMin;
+
+function defaultRemotePanelState() {
+  return {
+    writable: false,
+    mode: "unknown",
+    current_limit: null,
+    standby: null,
+    last_command: "",
+    last_error: "",
+    last_updated: ""
+  };
+}
+
+function defaultState() {
+  return {
+    output_current: null,
+    output_voltage: 0,
+    output_frequency: 0,
+    output_power: 0,
+    input_current: 0,
+    input_voltage: 0,
+    input_frequency: 0,
+    input_power: 0,
+    battery_current: 0,
+    battery_voltage: 0,
+    battery_charge: 0,
+    battery_power: 0,
+    led_map: {
+      led_mains: "dot-off",
+      led_absorb: "dot-off",
+      led_bulk: "dot-off",
+      led_float: "dot-off",
+      led_inverter: "dot-off",
+      led_overload: "dot-off",
+      led_bat_low: "dot-off",
+      led_over_temp: "dot-off"
+    },
+    remote_panel: defaultRemotePanelState()
+  };
+}
+
+function loadContent() {
+  app = new Vue({
+    el: "#app",
+    data: {
+      error: {
+        has_error: false,
+        error_message: ""
+      },
+      control: {
+        busy: false,
+        has_error: false,
+        message: ""
+      },
+      remote_form: {
+        mode: "on",
+        current_limit: "",
+        standby: false
+      },
+      state: defaultState()
+    },
+    methods: {
+      syncRemoteFormFromState: function(remoteState) {
+        if (!remoteState) {
+          return;
+        }
+        if (remoteState.mode && remoteState.mode !== "unknown") {
+          this.remote_form.mode = remoteState.mode;
+        }
+        if (remoteState.current_limit === null || remoteState.current_limit === undefined) {
+          this.remote_form.current_limit = "";
+        } else {
+          this.remote_form.current_limit = String(remoteState.current_limit);
+        }
+        if (remoteState.standby === null || remoteState.standby === undefined) {
+          this.remote_form.standby = false;
+        } else {
+          this.remote_form.standby = !!remoteState.standby;
+        }
+      },
+      remoteModeLabel: function(remoteState) {
+        var mode = (remoteState && remoteState.mode) || "unknown";
+        if (mode === "charger_only") {
+          return "Charger Only";
+        }
+        if (mode === "inverter_only") {
+          return "Inverter Only";
+        }
+        if (mode === "on") {
+          return "On";
+        }
+        if (mode === "off") {
+          return "Off";
+        }
+        return "Unknown";
+      },
+      remoteStandbyLabel: function(remoteState) {
+        if (!remoteState || remoteState.standby === null || remoteState.standby === undefined) {
+          return "Unknown";
+        }
+        return remoteState.standby ? "Enabled" : "Disabled";
+      },
+      refreshRemoteState: function() {
+        var self = this;
+        fetch(getAPIURI("api/remote-panel/state"))
+          .then(function(resp) {
+            if (!resp.ok) {
+              throw new Error("Could not load remote panel state.");
+            }
+            return resp.json();
+          })
+          .then(function(payload) {
+            self.state.remote_panel = payload;
+            self.syncRemoteFormFromState(payload);
+          })
+          .catch(function(err) {
+            self.control.has_error = true;
+            self.control.message = err.message;
+          });
+      },
+      applyRemotePanelState: function() {
+        var self = this;
+        if (!self.state.remote_panel.writable) {
+          return;
+        }
+
+        var body = {
+          mode: self.remote_form.mode
+        };
+        if (self.remote_form.current_limit !== "") {
+          var parsed = parseFloat(self.remote_form.current_limit);
+          if (isNaN(parsed)) {
+            self.control.has_error = true;
+            self.control.message = "Current limit must be numeric.";
+            return;
+          }
+          body.current_limit = parsed;
+        }
+
+        self.control.busy = true;
+        self.control.has_error = false;
+        self.control.message = "";
+        fetch(getAPIURI("api/remote-panel/state"), {
+          method: "POST",
+          headers: {
+            "Content-Type": "application/json"
+          },
+          body: JSON.stringify(body)
+        })
+          .then(function(resp) {
+            if (!resp.ok) {
+              return resp.text().then(function(text) {
+                throw new Error(text || "Failed to set remote panel mode/current limit.");
+              });
+            }
+            return resp.json();
+          })
+          .then(function(payload) {
+            self.state.remote_panel = payload;
+            self.syncRemoteFormFromState(payload);
+            self.control.has_error = false;
+            self.control.message = "Remote panel state updated.";
+          })
+          .catch(function(err) {
+            self.control.has_error = true;
+            self.control.message = err.message;
+          })
+          .finally(function() {
+            self.control.busy = false;
+          });
+      },
+      applyStandby: function() {
+        var self = this;
+        if (!self.state.remote_panel.writable) {
+          return;
+        }
+
+        self.control.busy = true;
+        self.control.has_error = false;
+        self.control.message = "";
+        fetch(getAPIURI("api/remote-panel/standby"), {
+          method: "POST",
+          headers: {
+            "Content-Type": "application/json"
+          },
+          body: JSON.stringify({
+            standby: !!self.remote_form.standby
+          })
+        })
+          .then(function(resp) {
+            if (!resp.ok) {
+              return resp.text().then(function(text) {
+                throw new Error(text || "Failed to set standby mode.");
+              });
+            }
+            return resp.json();
+          })
+          .then(function(payload) {
+            self.state.remote_panel = payload;
+            self.syncRemoteFormFromState(payload);
+            self.control.has_error = false;
+            self.control.message = "Standby mode updated.";
+          })
+          .catch(function(err) {
+            self.control.has_error = true;
+            self.control.message = err.message;
+          })
+          .finally(function() {
+            self.control.busy = false;
+          });
+      }
+    }
+  });
+
+  app.refreshRemoteState();
+  connect();
+}
+
+function connect() {
+  if (window["WebSocket"]) {
+    var conn = new WebSocket(getURI());
+    conn.onclose = function(evt) {
+      app.error.has_error = true;
+      app.error.error_message =
+        "Server not reachable. Trying to reconnect in " +
+        timeout / 1000 +
+        " second(s).";
+
+      console.log(app.error.error_message, evt.reason);
+      setTimeout(function() {
+        connect();
+      }, timeout);
+      timeout = timeout * 2;
+      if (timeout > timeoutMax) {
+        timeout = timeoutMax;
+      }
+    };
+
+    conn.onopen = function() {
+      timeout = timeoutMin;
+      app.error.has_error = false;
+    };
+
+    conn.onmessage = function(evt) {
+      var update = JSON.parse(evt.data);
+      app.state = update;
+      if (!app.control.busy) {
+        app.syncRemoteFormFromState(update.remote_panel);
+      }
+    };
+  } else {
+    app.error.has_error = true;
+    app.error.error_message = "Our browser does not support WebSockets.";
+  }
+}
+
+function getURI() {
+  var loc = window.location,
+    new_uri;
+  if (loc.protocol === "https:") {
+    new_uri = "wss:";
+  } else {
+    new_uri = "ws:";
+  }
+  new_uri += "//" + loc.host;
+  new_uri += loc.pathname + "ws";
+  return new_uri;
+}
+
+function getAPIURI(path) {
+  var base = window.location.pathname;
+  if (base.slice(-1) !== "/") {
+    base += "/";
+  }
+  return base + path.replace(/^\/+/, "");
+}

plugins/webui/static/root/css/bootstrap.min.css.map

@@ -1,88 +0,0 @@
-<!DOCTYPE html>
-<html>
-  <head>
-    <meta http-equiv="Content-type" content="text/html; charset=utf-8">
-    <meta http-equiv="Content-Security-Policy" content="default-src 'none'; style-src 'unsafe-inline'; img-src data:; connect-src 'self'">
-    <title>Page not found &middot; GitHub Pages</title>
-    <style type="text/css" media="screen">
-      body {
-        background-color: #f1f1f1;
-        margin: 0;
-        font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
-      }
-
-      .container { margin: 50px auto 40px auto; width: 600px; text-align: center; }
-
-      a { color: #4183c4; text-decoration: none; }
-      a:hover { text-decoration: underline; }
-
-      h1 { width: 800px; position:relative; left: -100px; letter-spacing: -1px; line-height: 60px; font-size: 60px; font-weight: 100; margin: 0px 0 50px 0; text-shadow: 0 1px 0 #fff; }
-      p { color: rgba(0, 0, 0, 0.5); margin: 20px 0; line-height: 1.6; }
-
-      ul { list-style: none; margin: 25px 0; padding: 0; }
-      li { display: table-cell; font-weight: bold; width: 1%; }
-
-      .logo { display: inline-block; margin-top: 35px; }
-      .logo-img-2x { display: none; }
-      @media
-      only screen and (-webkit-min-device-pixel-ratio: 2),
-      only screen and (   min--moz-device-pixel-ratio: 2),
-      only screen and (     -o-min-device-pixel-ratio: 2/1),
-      only screen and (        min-device-pixel-ratio: 2),
-      only screen and (                min-resolution: 192dpi),
-      only screen and (                min-resolution: 2dppx) {
-        .logo-img-1x { display: none; }
-        .logo-img-2x { display: inline-block; }
-      }
-
-      #suggestions {
-        margin-top: 35px;
-        color: #ccc;
-      }
-      #suggestions a {
-        color: #666666;
-        font-weight: 200;
-        font-size: 14px;
-        margin: 0 10px;
-      }
-
-    </style>
-  </head>
-  <body>
-
-    <div class="container">
-
-      <h1>404</h1>
-      <p><strong>File not found</strong></p>
-
-      <p>
-        The site configured at this address does not
-        contain the requested file.
-      </p>
-
-      <p>
-        If this is your site, make sure that the filename case matches the URL.<br>
-        For root URLs (like <code>http://example.com/</code>) you must provide an
-        <code>index.html</code> file.
-      </p>
-
-      <p>
-        <a href="https://help.github.com/pages/">Read the full documentation</a>
-        for more information about using <strong>GitHub Pages</strong>.
-      </p>
-
-      <div id="suggestions">
-        <a href="https://githubstatus.com">GitHub Status</a> &mdash;
-        <a href="https://twitter.com/githubstatus">@githubstatus</a>
-      </div>
-
-      <a href="/" class="logo logo-img-1x">
-        <img width="32" height="32" title="" alt="" src="data:image/png;base64,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">
-      </a>
-
-      <a href="/" class="logo logo-img-2x">
-        <img width="32" height="32" title="" alt="" src="data:image/png;base64,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">
-      </a>
-    </div>
-  </body>
-</html>

plugins/webui/static/root/js/controller.js

@@ -1,90 +0,0 @@
-var app;
-const timeoutMax = 30000;
-const timeoutMin = 1000;
-var timeout = timeoutMin;
-
-function loadContent() {
-  app = new Vue({
-    el: "#app",
-    data: {
-      error: {
-        has_error: false,
-        error_message: ""
-      },
-      state: {
-        output_current: null,
-        output_voltage: 0,
-        output_frequency: 0,
-        output_power: 0,
-        input_current: 0,
-        input_voltage: 0,
-        input_frequency: 0,
-        input_power: 0,
-        battery_current: 0,
-        battery_voltage: 0,
-        battery_charge: 0,
-        battery_power: 0,
-        led_map: [
-          { led_mains: "dot-off" },
-          { led_absorb: "dot-off" },
-          { led_bulk: "dot-off" },
-          { led_float: "dot-off" },
-          { led_inverter: "dot-off" },
-          { led_overload: "dot-off" },
-          { led_bat_low: "dot-off" },
-          { led_over_temp: "dot-off" }
-        ]
-      }
-    }
-  });
-
-  connect();
-}
-
-function connect() {
-  if (window["WebSocket"]) {
-    var conn = new WebSocket(getURI());
-    conn.onclose = function(evt) {
-      app.error.has_error = true;
-      app.error.error_message =
-        "Server not reachable. Trying to reconnect in " +
-        timeout / 1000 +
-        " second(s).";
-
-      console.log(app.error.error_message, evt.reason);
-      setTimeout(function() {
-        connect();
-      }, timeout);
-      timeout = timeout * 2;
-      if (timeout > timeoutMax) {
-        timeout = timeoutMax;
-      }
-    };
-
-    conn.onopen = function(evt) {
-      timeout = timeoutMin;
-      app.error.has_error = false;
-    };
-
-    conn.onmessage = function(evt) {
-      var update = JSON.parse(evt.data);
-      app.state = update;
-    };
-  } else {
-    app.error.has_error = true;
-    app.error.error_message = "Our browser does not support WebSockets.";
-  }
-}
-
-function getURI() {
-  var loc = window.location,
-    new_uri;
-  if (loc.protocol === "https:") {
-    new_uri = "wss:";
-  } else {
-    new_uri = "ws:";
-  }
-  new_uri += "//" + loc.host;
-  new_uri += loc.pathname + "ws";
-  return new_uri;
-}

plugins/webui/webgui.go

@@ -31,16 +31,20 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 package webui
 
 import (
+	"encoding/json"
 	"fmt"
-	"log"
 	"net/http"
+	"strings"
 	"sync"
 	"time"
 
-	"github.com/diebietse/invertergui/mk2driver"
-	"github.com/diebietse/invertergui/websocket"
+	"git.coadcorp.com/nathan/invertergui/mk2driver"
+	"git.coadcorp.com/nathan/invertergui/websocket"
+	"github.com/sirupsen/logrus"
 )
 
+var log = logrus.WithField("ctx", "inverter-gui-webgui")
+
 const (
 	LedOff     = "dot-off"
 	LedRed     = "dot-red"
@@ -49,25 +53,54 @@ const (
 	BlinkGreen = "blink-green"
 )
 
+const (
+	modeChargerOnly  = "charger_only"
+	modeInverterOnly = "inverter_only"
+	modeOn           = "on"
+	modeOff          = "off"
+	modeUnknown      = "unknown"
+)
+
 type WebGui struct {
 	mk2driver.Mk2
+	writer   mk2driver.SettingsWriter
 	stopChan chan struct{}
 
 	wg  sync.WaitGroup
 	hub *websocket.Hub
+
+	stateMu sync.RWMutex
+	latest  *templateInput
+	remote  remotePanelState
 }
 
-func NewWebGui(source mk2driver.Mk2) *WebGui {
+func NewWebGui(source mk2driver.Mk2, writer mk2driver.SettingsWriter) *WebGui {
 	w := &WebGui{
 		stopChan: make(chan struct{}),
 		Mk2:      source,
+		writer:   writer,
 		hub:      websocket.NewHub(),
+		remote: remotePanelState{
+			Writable: writer != nil,
+			Mode:     modeUnknown,
+		},
 	}
+	log.WithField("remote_writable", writer != nil).Info("Web UI initialized")
 	w.wg.Add(1)
 	go w.dataPoll()
 	return w
 }
 
+type remotePanelState struct {
+	Writable     bool     `json:"writable"`
+	Mode         string   `json:"mode"`
+	CurrentLimit *float64 `json:"current_limit,omitempty"`
+	Standby      *bool    `json:"standby,omitempty"`
+	LastCommand  string   `json:"last_command,omitempty"`
+	LastError    string   `json:"last_error,omitempty"`
+	LastUpdated  string   `json:"last_updated,omitempty"`
+}
+
 type templateInput struct {
 	Error []error `json:"errors"`
 
@@ -92,12 +125,170 @@ type templateInput struct {
 	OutFreq string `json:"output_frequency"`
 
 	LedMap map[string]string `json:"led_map"`
+
+	RemotePanel remotePanelState `json:"remote_panel"`
+}
+
+type setRemotePanelStateRequest struct {
+	Mode         string   `json:"mode"`
+	CurrentLimit *float64 `json:"current_limit"`
+}
+
+type setRemotePanelStandbyRequest struct {
+	Standby bool `json:"standby"`
 }
 
 func (w *WebGui) ServeHub(rw http.ResponseWriter, r *http.Request) {
+	log.WithFields(logrus.Fields{
+		"remote": r.RemoteAddr,
+		"path":   r.URL.Path,
+	}).Debug("WebSocket hub request")
 	w.hub.ServeHTTP(rw, r)
 }
 
+func (w *WebGui) ServeRemotePanelState(rw http.ResponseWriter, r *http.Request) {
+	log.WithFields(logrus.Fields{
+		"method": r.Method,
+		"path":   r.URL.Path,
+		"remote": r.RemoteAddr,
+	}).Debug("Remote panel state API request")
+
+	switch r.Method {
+	case http.MethodGet:
+		writeJSON(rw, http.StatusOK, w.getRemotePanelState())
+	case http.MethodPost:
+		w.handleSetRemotePanelState(rw, r)
+	default:
+		log.WithField("method", r.Method).Warn("Remote panel state API received unsupported method")
+		http.Error(rw, "method not allowed", http.StatusMethodNotAllowed)
+	}
+}
+
+func (w *WebGui) ServeRemotePanelStandby(rw http.ResponseWriter, r *http.Request) {
+	log.WithFields(logrus.Fields{
+		"method": r.Method,
+		"path":   r.URL.Path,
+		"remote": r.RemoteAddr,
+	}).Debug("Remote panel standby API request")
+
+	switch r.Method {
+	case http.MethodGet:
+		writeJSON(rw, http.StatusOK, w.getRemotePanelState())
+	case http.MethodPost:
+		w.handleSetRemotePanelStandby(rw, r)
+	default:
+		log.WithField("method", r.Method).Warn("Remote panel standby API received unsupported method")
+		http.Error(rw, "method not allowed", http.StatusMethodNotAllowed)
+	}
+}
+
+func (w *WebGui) handleSetRemotePanelState(rw http.ResponseWriter, r *http.Request) {
+	if w.writer == nil {
+		log.Warn("Remote panel state write requested, but writer is unavailable")
+		http.Error(rw, "remote control is not supported by this data source", http.StatusNotImplemented)
+		return
+	}
+
+	req := setRemotePanelStateRequest{}
+	if err := decodeJSONBody(r, &req); err != nil {
+		log.WithError(err).Warn("Invalid remote panel state request body")
+		http.Error(rw, err.Error(), http.StatusBadRequest)
+		return
+	}
+	logEntry := log.WithField("mode", req.Mode)
+	if req.CurrentLimit != nil {
+		logEntry = logEntry.WithField("current_limit_a", *req.CurrentLimit)
+	}
+	logEntry.Info("Applying remote panel state from API")
+
+	switchState, normalizedMode, err := parsePanelMode(req.Mode)
+	if err != nil {
+		logEntry.WithError(err).Warn("Unsupported remote panel mode")
+		http.Error(rw, err.Error(), http.StatusBadRequest)
+		return
+	}
+
+	var setErr error
+	if sourceAware, ok := w.writer.(mk2driver.SourceAwareSettingsWriter); ok {
+		setErr = sourceAware.SetPanelStateWithSource(mk2driver.CommandSourceUI, switchState, req.CurrentLimit)
+	} else {
+		setErr = w.writer.SetPanelState(switchState, req.CurrentLimit)
+	}
+	if setErr != nil {
+		logEntry.WithError(setErr).Error("Failed to apply remote panel state")
+		w.updateRemotePanelState(func(state *remotePanelState) {
+			state.LastCommand = "set_remote_panel_state"
+			state.LastError = setErr.Error()
+		})
+		http.Error(rw, setErr.Error(), http.StatusBadGateway)
+		return
+	}
+
+	w.updateRemotePanelState(func(state *remotePanelState) {
+		state.Mode = normalizedMode
+		state.CurrentLimit = copyFloat64Ptr(req.CurrentLimit)
+		state.LastCommand = "set_remote_panel_state"
+		state.LastError = ""
+	})
+	logEntry.WithField("normalized_mode", normalizedMode).Info("Remote panel state applied")
+	writeJSON(rw, http.StatusOK, w.getRemotePanelState())
+}
+
+func (w *WebGui) handleSetRemotePanelStandby(rw http.ResponseWriter, r *http.Request) {
+	if w.writer == nil {
+		log.Warn("Remote panel standby write requested, but writer is unavailable")
+		http.Error(rw, "remote control is not supported by this data source", http.StatusNotImplemented)
+		return
+	}
+
+	req := setRemotePanelStandbyRequest{}
+	if err := decodeJSONBody(r, &req); err != nil {
+		log.WithError(err).Warn("Invalid remote panel standby request body")
+		http.Error(rw, err.Error(), http.StatusBadRequest)
+		return
+	}
+	log.WithField("standby", req.Standby).Info("Applying standby state from API")
+
+	var err error
+	if sourceAware, ok := w.writer.(mk2driver.SourceAwareSettingsWriter); ok {
+		err = sourceAware.SetStandbyWithSource(mk2driver.CommandSourceUI, req.Standby)
+	} else {
+		err = w.writer.SetStandby(req.Standby)
+	}
+	if err != nil {
+		log.WithError(err).WithField("standby", req.Standby).Error("Failed to apply standby state")
+		w.updateRemotePanelState(func(state *remotePanelState) {
+			state.LastCommand = "set_remote_panel_standby"
+			state.LastError = err.Error()
+		})
+		http.Error(rw, err.Error(), http.StatusBadGateway)
+		return
+	}
+
+	w.updateRemotePanelState(func(state *remotePanelState) {
+		state.Standby = copyBoolPtr(&req.Standby)
+		state.LastCommand = "set_remote_panel_standby"
+		state.LastError = ""
+	})
+	log.WithField("standby", req.Standby).Info("Standby state applied")
+	writeJSON(rw, http.StatusOK, w.getRemotePanelState())
+}
+
+func parsePanelMode(raw string) (mk2driver.PanelSwitchState, string, error) {
+	switch strings.TrimSpace(strings.ToLower(raw)) {
+	case modeChargerOnly:
+		return mk2driver.PanelSwitchChargerOnly, modeChargerOnly, nil
+	case modeInverterOnly:
+		return mk2driver.PanelSwitchInverterOnly, modeInverterOnly, nil
+	case modeOn:
+		return mk2driver.PanelSwitchOn, modeOn, nil
+	case modeOff:
+		return mk2driver.PanelSwitchOff, modeOff, nil
+	default:
+		return 0, "", fmt.Errorf("unsupported panel mode %q", raw)
+	}
+}
+
 func ledName(led mk2driver.Led) string {
 	name, ok := mk2driver.LedNames[led]
 	if !ok {
@@ -156,21 +347,32 @@ func buildTemplateInput(status *mk2driver.Mk2Info) *templateInput {
 }
 
 func (w *WebGui) Stop() {
+	log.Info("Stopping Web UI polling")
 	close(w.stopChan)
 	w.wg.Wait()
+	log.Info("Web UI polling stopped")
 }
 
-// dataPoll waits for data from the w.poller channel. It will send its currently stored status
-// to respChan if anything reads from it.
 func (w *WebGui) dataPoll() {
 	for {
 		select {
 		case s := <-w.C():
-			if s.Valid {
-				err := w.hub.Broadcast(buildTemplateInput(s))
-				if err != nil {
-					log.Printf("Could not send update to clients: %v", err)
+			if s == nil {
+				log.Debug("Skipping nil MK2 update in Web UI poller")
+				continue
 			}
+			if !s.Valid {
+				log.WithField("errors", len(s.Errors)).Debug("Skipping invalid MK2 update in Web UI poller")
+				continue
+			}
+
+			payload := buildTemplateInput(s)
+			w.stateMu.Lock()
+			payload.RemotePanel = w.remote
+			w.latest = payload
+			w.stateMu.Unlock()
+			if err := w.hub.Broadcast(payload); err != nil {
+				log.Errorf("Could not send update to clients: %v", err)
 			}
 		case <-w.stopChan:
 			w.wg.Done()
@@ -178,3 +380,100 @@ func (w *WebGui) dataPoll() {
 		}
 	}
 }
+
+func (w *WebGui) getRemotePanelState() remotePanelState {
+	w.stateMu.RLock()
+	defer w.stateMu.RUnlock()
+	return copyRemotePanelState(w.remote)
+}
+
+func (w *WebGui) updateRemotePanelState(update func(state *remotePanelState)) {
+	w.stateMu.Lock()
+	update(&w.remote)
+	w.remote.LastUpdated = time.Now().UTC().Format(time.RFC3339)
+	log.WithFields(logrus.Fields{
+		"mode":         w.remote.Mode,
+		"has_limit":    w.remote.CurrentLimit != nil,
+		"has_standby":  w.remote.Standby != nil,
+		"last_command": w.remote.LastCommand,
+		"last_error":   w.remote.LastError,
+	}).Debug("Updated remote panel state cache")
+	snapshot := w.snapshotLocked()
+	w.stateMu.Unlock()
+
+	if snapshot != nil {
+		if err := w.hub.Broadcast(snapshot); err != nil {
+			log.Errorf("Could not send control update to clients: %v", err)
+		}
+	}
+}
+
+func (w *WebGui) snapshotLocked() *templateInput {
+	if w.latest == nil {
+		return nil
+	}
+
+	snapshot := cloneTemplateInput(w.latest)
+	snapshot.RemotePanel = copyRemotePanelState(w.remote)
+	return snapshot
+}
+
+func cloneTemplateInput(in *templateInput) *templateInput {
+	if in == nil {
+		return nil
+	}
+	out := *in
+
+	if in.Error != nil {
+		out.Error = append([]error(nil), in.Error...)
+	}
+	if in.LedMap != nil {
+		out.LedMap = make(map[string]string, len(in.LedMap))
+		for k, v := range in.LedMap {
+			out.LedMap[k] = v
+		}
+	}
+
+	out.RemotePanel = copyRemotePanelState(in.RemotePanel)
+	return &out
+}
+
+func copyRemotePanelState(in remotePanelState) remotePanelState {
+	in.CurrentLimit = copyFloat64Ptr(in.CurrentLimit)
+	in.Standby = copyBoolPtr(in.Standby)
+	return in
+}
+
+func copyFloat64Ptr(in *float64) *float64 {
+	if in == nil {
+		return nil
+	}
+	value := *in
+	return &value
+}
+
+func copyBoolPtr(in *bool) *bool {
+	if in == nil {
+		return nil
+	}
+	value := *in
+	return &value
+}
+
+func decodeJSONBody(r *http.Request, destination any) error {
+	defer r.Body.Close()
+	decoder := json.NewDecoder(r.Body)
+	decoder.DisallowUnknownFields()
+	if err := decoder.Decode(destination); err != nil {
+		return fmt.Errorf("invalid request body: %w", err)
+	}
+	return nil
+}
+
+func writeJSON(rw http.ResponseWriter, statusCode int, payload any) {
+	rw.Header().Set("Content-Type", "application/json")
+	rw.WriteHeader(statusCode)
+	if err := json.NewEncoder(rw).Encode(payload); err != nil {
+		log.Errorf("Could not encode webui API response: %v", err)
+	}
+}

plugins/webui/webgui_test.go

@@ -36,7 +36,7 @@ import (
 	"testing"
 	"time"
 
-	"github.com/diebietse/invertergui/mk2driver"
+	"git.coadcorp.com/nathan/invertergui/mk2driver"
 )
 
 type templateTest struct {
@@ -91,3 +91,53 @@ func TestTemplateInput(t *testing.T) {
 		}
 	}
 }
+
+func TestParsePanelMode(t *testing.T) {
+	tests := []struct {
+		name    string
+		input   string
+		want    mk2driver.PanelSwitchState
+		wantRaw string
+		wantErr bool
+	}{
+		{
+			name:    "on",
+			input:   "on",
+			want:    mk2driver.PanelSwitchOn,
+			wantRaw: "on",
+		},
+		{
+			name:    "charger_only",
+			input:   "charger_only",
+			want:    mk2driver.PanelSwitchChargerOnly,
+			wantRaw: "charger_only",
+		},
+		{
+			name:    "invalid",
+			input:   "banana",
+			wantErr: true,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got, gotRaw, err := parsePanelMode(tt.input)
+			if tt.wantErr {
+				if err == nil {
+					t.Fatal("expected error, got nil")
+				}
+				return
+			}
+
+			if err != nil {
+				t.Fatalf("unexpected error: %v", err)
+			}
+			if got != tt.want {
+				t.Fatalf("got switch %d, want %d", got, tt.want)
+			}
+			if gotRaw != tt.wantRaw {
+				t.Fatalf("got mode %q, want %q", gotRaw, tt.wantRaw)
+			}
+		})
+	}
+}