coresync/src/identity.js

'use strict';

const DEFAULT_UNITS = {
  pressure: 'Pa',
  flow: 'm3/s',
  power: 'W',
  temperature: 'K',
  density: 'kg/m3',
  level: 'm',
  volume: 'm3',
  control: '1',
  percentage: '1',
  efficiency: '1',
};

function firstPresent(...values) {
  for (const value of values) {
    if (value !== undefined && value !== null && value !== '') return value;
  }
  return undefined;
}

function sanitizeToken(value, fallback) {
  const raw = firstPresent(value, fallback);
  return String(raw || '').trim();
}

function parseFieldKey(fieldKey) {
  const parts = String(fieldKey || '').split('.').filter(Boolean);
  return {
    type: parts[0] || 'value',
    variant: parts[1] || 'measured',
    position: parts[2] || 'atEquipment',
    sensorTag: parts[3] || undefined,
  };
}

function resolveIdentity(input, options = {}) {
  const tags = input.tags || {};
  const parsed = parseFieldKey(input.fieldKey);
  const thingTag = sanitizeToken(
    options.assetTagOverride,
    tags.tagcode || tags.tagCode || tags.asset_tagCode || tags.asset_tagcode || input.measurement,
  );
  const type = sanitizeToken(input.type, parsed.type).toLowerCase();
  const variant = sanitizeToken(input.variant, parsed.variant).toLowerCase();
  const position = sanitizeToken(input.position, parsed.position);
  const sensorTag = sanitizeToken(
    options.sensorTagOverride,
    parsed.sensorTag || tags.sensorTag || tags.sensor_tagCode || `${variant.toUpperCase()}-${thingTag}`,
  );
  const unit = sanitizeToken(input.unit, tags.unit || input.source?.unit || DEFAULT_UNITS[type] || '1');
  const streamKey = [thingTag, type, variant, position, sensorTag].join(':');

  return {
    thingTag,
    type,
    variant,
    position,
    sensorTag,
    unit,
    fieldKey: input.fieldKey,
    streamKey,
    thingExternalKey: `thing:${thingTag}`,
    observedPropertyExternalKey: `observedProperty:${type}`,
    sensorExternalKey: `sensor:${sensorTag}`,
    featureOfInterestExternalKey: `foi:${thingTag}:${position}`,
    datastreamExternalKey: `datastream:${streamKey}`,
  };
}

module.exports = {
  DEFAULT_UNITS,
  parseFieldKey,
  resolveIdentity,
};