/**
 * v1.18.1 — shared lab-value number formatting.
 *
 * The list card, the detail history rows, and the chart tooltip all trim a
 * lab reading the same way: whole numbers render bare, fractional values keep
 * up to two decimals (no trailing-zero noise). Centralised so the three
 * surfaces stay byte-identical.
 *
 * The digits themselves come from the caller's locale number formatter
 * (`useFormatters().number`), so a German reader sees "1,8 mIU/L" where an
 * English one sees "1.8 mIU/L". This module only decides the precision.
 */
export type LabNumberFormat = (value: number) => string;

export function formatLabValue(
  value: number,
  formatNumber: LabNumberFormat,
): string {
  return formatNumber(
    Number.isInteger(value) ? value : Number(value.toFixed(2)),
  );
}

/**
 * v1.18.9 — render a reading's display value: a qualitative row (numeric
 * `value` is null) shows its `valueText` verbatim; a numeric row shows the
 * formatted number plus its unit. One helper so the list card, the history
 * rows, and the detail header stay consistent.
 */
export function formatLabReading(
  reading: {
    value: number | null;
    valueText: string | null;
    unit: string;
  },
  formatNumber: LabNumberFormat,
): string {
  if (reading.value === null) {
    return reading.valueText ?? "";
  }
  return `${formatLabValue(reading.value, formatNumber)} ${reading.unit}`.trim();
}