# Measurement Function Anchor (Preparation Baseline)

## 0) Connection Map (At a Glance)
- **Node type**: `measurement` (`nodes/measurement/measurement.js:1`, `nodes/measurement/measurement.html:14`)
- **Consumes topics**: `measurement`, `simulator`, `outlierDetection`, `calibrate` (`nodes/measurement/src/nodeClass.js:147`)
- **Publishes periodic outputs**:
  - Output `0`: process payload (`nodes/measurement/src/nodeClass.js:137`)
  - Output `1`: influx payload (`nodes/measurement/src/nodeClass.js:138`)
  - Output `2`: parent registration (`registerChild`) (`nodes/measurement/src/nodeClass.js:118`)
- **Cross-node integrations (direct observed)**:
  - Registers as child to parent with `positionVsParent` and optional `distance` (`nodes/measurement/src/nodeClass.js:118`)
  - Emits measurement updates through `MeasurementContainer` in `specificClass` (`nodes/measurement/src/specificClass.js:479`)
- **Admin/UI endpoints**:
  - `GET /measurement/menu.js` (`nodes/measurement/measurement.js:23`)
  - `GET /measurement/configData.js` (`nodes/measurement/measurement.js:33`)
  - `POST /measurement/asset-reg` (`nodes/measurement/measurement.js:43`)

## 1) Unit Table (Initial Baseline)
| Signal/Field | Represents | Default Unit | Source of Truth | Produced By | Consumed By | Fallback/Degraded Behavior |
|---|---|---|---|---|---|---|
| `inputValue` | raw measurement input | asset-dependent | `nodes/measurement/src/specificClass.js:30` | `measurement` topic or simulator | scaling/smoothing pipeline | defaults to `0` |
| `outputAbs` (`mAbs`) | processed absolute output | `config.asset.unit` | `nodes/measurement/src/specificClass.js:472` | `updateOutputAbs()` | process/influx outputs + event emitter | constrained to configured abs range |
| `outputPercent` (`mPercent`) | normalized percent-like output | `%` semantic | `nodes/measurement/src/specificClass.js:483` | `updateOutputPercent()` | process/influx outputs | interpolated from abs range or observed min/max |
| `storedValues` | smoothing window values | same as processed value | `nodes/measurement/src/specificClass.js:24` | `applySmoothing()` | smoothing and repeatability checks | capped to `smoothWindow` length |
| `simulation.enabled` | internal simulated signal mode | boolean | `nodes/measurement/src/specificClass.js:52` | config/topic toggle | `tick()` behavior | off by default |

## 2) Class Identity
- **Runtime registration + endpoints**: `nodes/measurement/measurement.js`
- **Node-RED wrapper/routing**: `nodes/measurement/src/nodeClass.js`
- **Domain measurement logic**: `nodes/measurement/src/specificClass.js`
- **Editor UI/defaults**: `nodes/measurement/measurement.html`

## 3) Current Gaps To Resolve Before Declaring Anchor Complete
1. Node label precedence can hide fallback text due to expression order:
- `return this.positionIcon + " " + this.assetType || "Measurement";` (`nodes/measurement/measurement.html:63`)
2. `success` variable is assigned without declaration in editor save path:
- `success = window.EVOLV.nodes.measurement.assetMenu.saveEditor(this);` (`nodes/measurement/measurement.html:131`)
3. `toggleOutlierDetection()` mutates config object to boolean:
- `this.config.outlierDetection = !this.config.outlierDetection;` (`nodes/measurement/src/specificClass.js:503`)
4. Input handler ignores numeric strings for `measurement` topic:
- accepts only `typeof msg.payload === 'number'` (`nodes/measurement/src/nodeClass.js:152`)

## 4) Standardization Plan (Mirror RotatingMachine)
1. Keep this anchor pair (`.md` + `.html`) and evidence file maintained with behavior changes.
2. Maintain test layout under `nodes/measurement/test/`:
- `basic/`, `integration/`, `edge/`, `helpers/`
3. Maintain examples package under `nodes/measurement/examples/`:
- `README.md`, `basic.flow.json`, `integration.flow.json`, `edge.flow.json`

## 5) Acceptance Criteria For Completion
- Required anchor artifacts exist and map to current behavior.
- Test suite runs with node-level command.
- Example flow files exist and pass flow-structure tests.