import { emptySpeedProbeObservations, sameSpeedMeasurement, type SpeedMeasurementParameters, type SpeedProbeRead } from "@mmapp/contracts"
type Observations = Pick<SpeedProbeRead, keyof typeof emptySpeedProbeObservations>
type Pair = { id: string } & SpeedMeasurementParameters
/** Publish confirmed configuration while preserving the latest snapshot only for the same measurement parameters. */
export function publishSpeedProbeSnapshots<T extends Pair & Partial<Observations>>(previous: readonly T[], next: readonly T[]) {
  const byId = new Map(previous.map(row => [row.id, row]))
  return next.map(row => {
    const old = byId.get(row.id)
    if (!old || !sameSpeedMeasurement(old, row)) {
      return { ...row, ...emptySpeedProbeObservations }
    }
    const observations = Object.fromEntries(Object.keys(emptySpeedProbeObservations).map(key => [key, old[key as keyof Observations] ?? null])) as Observations
    return { ...row, ...observations }
  })
}